Fairfield, CT, United States

General Electric

ge.com
Fairfield, CT, United States

General Electric is an American multinational conglomerate corporation incorporated in New York and headquartered in Fairfield, Connecticut. The company operates through the following segments: Energy , Technology Infrastructure, Capital Finance as well as Consumer and Industrial.In 2011, GE ranked among the Fortune 500 as the 26th-largest firm in the U.S. by gross revenue, as well as the 14th most profitable. However, the company is listed the fourth-largest in the world among the Forbes Global 2000, further metrics being taken into account. Other rankings for 2011/2012 include No. 7 company for leaders , No. 5 best global brand , No. 63 green company , No. 15 most admired company , and No. 19 most innovative company . Wikipedia.

SEARCH TERMS
SEARCH FILTERS
Time filter
Source Type

In one embodiment, an energy storage system includes a plurality of energy storage banks. The plurality of energy storage banks include a first set of one or more energy storage banks and a second set of one or more energy storage banks. The first set of the energy storage banks is associated with a faster charge/discharge rate relative to the second set of energy storage banks. The energy storage system includes at least one control device that is configured to control the first set of energy storage banks to accept or discharge energy in response to fluctuations in a power signal associated with a first frequency; and is further configured to control the second set of energy storage banks to accept or discharge energy in response to fluctuations in the power signal associated with a second frequency. The first frequency is greater than the second frequency.

Claims which contain your search:

1. An energy storage system, the energy storage system comprising: a plurality of energy storage banks that respectively comprise one or more energy storage devices, wherein the plurality of energy storage banks comprise a first set of one or more energy storage banks and a second set of one or more energy storage banks, and wherein the first set of the energy storage banks is associated with a faster charge/discharge rate relative to the second set of energy storage banks; and at least one control device that is configured to control the first set of energy storage banks to accept or discharge energy in response to fluctuations in a power signal associated with a first frequency, the at least one control device further configured to control the second set of energy storage banks to accept or discharge energy in response to fluctuations in the power signal associated with a second frequency, the first frequency being greater than the second frequency.

2. The energy storage system of claim 1, further comprising: a system transformer configured to electrically connect the plurality of energy storage banks to an energy grid from which the power signal is received; wherein the first set of energy storage banks are located physically closer to the system transformer than the second set of energy storage banks.

3. The energy storage system of claim 1, wherein the first set of energy storage banks provides about 8 to 15 percent of a total storage capacity of the plurality of energy storage banks.

4. The energy storage system of claim 3, wherein the first set of energy storage banks provides about 10 percent of the total storage capacity of the plurality of energy storage banks.

5. The energy storage system of claim 1, wherein the first set of energy storage banks comprises one or more lithium-ion batteries.

6. The energy storage system of claim 1, wherein the first set of energy storage banks comprises one or more ultracapacitors.

7. The energy storage system of claim 1, wherein the second set of energy storage banks comprises one or more sodium metal halide batteries.

8. The energy storage system of claim 1, wherein each of the first set of energy storage banks are electrically coupled in parallel with each of the second set of energy storage banks.

9. The energy storage system of claim 1, further comprising: a plurality of power converters respectively associated with the plurality of energy storage banks, wherein the power converter for each energy storage bank is configured to convert the power signal to a direct current bank signal.

10. The energy storage system of claim 9, wherein: the least one control device comprises a plurality of controllers respectively associated with the plurality of energy storage banks; and the controller for each energy storage bank is configured to control the corresponding power converter for such energy storage bank according to a time constant associated with such power converter.

11. The energy storage system of claim 10, wherein the time constant associated with each of the power converters for the first set of energy storage banks is smaller than the time constant associated with each of the power converters for the second set of energy storage banks.

12. The energy storage system of claim 10, wherein: each of the plurality of controllers is configured to periodically evaluate a performance of its corresponding power converter and adjust one or more power converter control parameters based at least in part on the evaluation.

13. A method to control an energy storage system, the method comprising: electrically coupling the energy storage system to a power system, the energy storage system comprising a plurality of energy storage banks that respectively comprise one or more energy storage devices, wherein the plurality of energy storage banks comprise at least a first energy storage bank and a second energy storage bank, and wherein the first energy storage bank has a relatively faster charge/discharge rate than the second energy storage bank; controlling, by at least one control device, the first energy storage bank to accept or discharge energy in response to fluctuations in a power signal associated with a first frequency; and controlling, by the at least one control device, the second energy storage bank to accept or discharge energy in response to fluctuations in the power signal associated with a second frequency, the first frequency being greater than the second frequency.

14. The method of claim 13, wherein: the energy storage system further comprises at least a first power converter electrically coupled to the first energy storage bank and at least a second power converter electrically coupled to the second energy storage bank; controlling, by the at least one control device, the first energy storage bank comprises controlling, by the at least one control device, the first power converter according to a first set of control parameters such that the first power converter exhibits a first time constant; controlling, by the at least one control device, the second energy storage bank comprises controlling, by the at least one control device, the second power converter according to a second set of control parameters such that the second power converter exhibits a second time constant, wherein the second time constant is relatively larger than the first time constant.

15. The method of claim 13, further comprising: adjusting, by the at least one control device, at least one of the first set of control parameters based on a first feedback loop that evaluates a first current associated with the first energy storage bank; and adjusting, by the at least one control device, at least one of the second set of control parameters based on a second feedback loop that evaluates a second current associated with the second energy storage bank.

16. A wind power system comprising: a wind turbine power system; a first energy storage device; a first power converter electrically coupled between the first energy storage device and the wind turbine power system; a second energy storage device, wherein the second energy storage device has a relatively smaller charge/discharge rate than the first energy storage device; a second power converter electrically coupled between the second energy storage device and the wind turbine power system; and at least one control device that controls the first power converter according to a first time constant and controls the second power converter according to a second time constant; wherein the first time constant is relatively smaller than the second time constant such that the first power converter enables the first energy storage device to accept and discharge energy relatively faster than the second power converter enables the second energy storage device to accept and discharge energy.

18. The wind power system of claim 17, wherein: the first controller periodically adjusts the first time constant based at least in part on a first current associated with the first energy storage device; and the second controller periodically adjusts the second time constant based at least in part on a second current associated with the second energy storage device.

19. The wind power system of claim 16, wherein the first energy storage device provides about 10 percent of a total storage capacity provided by the first and the second energy storage devices.

20. The wind power system of claim 16, wherein the first energy storage device comprises one or more lithium-ion batteries or one or more ultracapacitors.


Patent
General Electric | Date: 2017-01-04

Systems 100 and methods 500 for controlling the state of charge of an energy storage system 200 used in conjunction with a renewable energy source or other power generation system are provided. More particularly, a future output requirement of the energy storage system 200 can be predicted based at least in part on data indicative of anticipated conditions, such as weather conditions, wake conditions, or other suitable conditions. A control system 250 can adjust a state of charge setpoint from a nominal setpoint (e.g. 50%) to an adjusted setpoint based at least in part on the future output requirement. In this way, the energy storage system 200 can better accommodate the output requirements of the energy storage system 200 during varying weather conditions.

Claims which contain your search:

1. A method (500) for controlling an energy storage system (200) associated with a power generation system (100), comprising:accessing (502), by one or more control devices (250), data indicative of anticipated conditions for a predetermined time period;determining (504), by the one or more control devices, a future output requirement of the energy storage system for the predetermined time period based at least in part on the data indicative of the anticipated weather conditions;adjusting (506), by the one or more control devices, a state of charge setpoint for the energy storage system based at least in part on the future output requirement; andcontrolling (512), by the one or more control devices, the delivery of power to or from the energy storage system based at least in part on the state of charge setpoint.

4. The method (500) of claim 3, wherein the adjusted setpoint is greater than the nominal setpoint when the future output requirement is determined to be increased relative to a current output requirement of the energy storage system.

5. The method (500) of any preceding claim, wherein controlling (512), by the one or more control devices, the delivery of power to or from the energy storage system (200) comprises:receiving (508), by the one or more computing devices, a signal indicative of the current state of charge of the energy storage system; andgenerating (510), by the one or more computing devices, a power command for the power generation system based at least in part on the signal indicative of the current state of charge of the energy storage system and the state of charge setpoint.

6. The method (500) of claim 5, wherein the power command is determined based at least in part on a maximum output power for the power generation system (100) when the state of charge setpoint is greater than the current state of charge of the energy storage system.

7. The method (500) of any preceding claim, wherein controlling (512|), by the one or more control devices, the delivery of power to or from the energy storage system (200) comprises delivering power generated by the power generation system that is in excess of an output power requirement for the power generation system during the predetermined time period to the energy storage system to increase the state of charge of the energy storage system.

10. The method (500) of any preceding claim, wherein the energy storage system (200) comprises a battery energy storage system.

11. A control system (250) for controlling an energy storage system (200) associated with a renewable energy system (100), the control system (250) comprising:a state of charge adjustment module (310) implemented by one or more control devices, the state of charge adjustment module configured to adjust a state of charge setpoint for the energy storage system based at least in part on data indicative of anticipated weather conditions;a renewable energy control module (320) implemented by the one or more control devices, the renewable energy control module configured to generate a power command for the renewable energy system based at least in part on the state of charge setpoint and a current state of charge for the energy storage system; anda charge control module (330) implemented by the one or more control devices, the charge controller configured to control the delivery of power to or from the energy storage system based at least in part on the state of charge setpoint.

12. The control system (250) of claim 11, wherein the state of charge adjustment module is configured to adjust the state of charge setpoint to accommodate a future output requirement of the energy storage system (200).

13. The control system (250) of claim 11 or claim 12, wherein the state of charge adjustment module (310) is configured to adjust the state of charge setpoint from a nominal setpoint to an adjusted setpoint, the adjusted setpoint being greater than the nominal setpoint when the future output requirement of the energy storage system is greater than a current output requirement of the energy storage system.

14. The control system (250) of any of claims 11 to 13, wherein the renewable energy control module (320) is configured to generate the power command based at least in part on a maximum output power for the renewable energy system when the state of charge setpoint is greater than the current state of charge of the energy storage system.

15. A wind turbine system (100), comprising:a wind driven generator (106);a power converter (162) coupled to the wind driven generator, the power converter comprising a DC bus;a battery energy storage system (200) coupled to the DC bus of the power converter, the battery energy storage system comprising one or more battery cells;a control system (250) configured to control the delivery of power to or from the battery energy storage system (250) based at least in part on a state of charge setpoint;wherein the control system (250) is configured to adjust the state of charge setpoint for the battery energy storage system (200) based at least in part on data indicative of anticipated weather conditions for a predetermined time period.


Systems and methods for controlling an energy storage system are provided. In particular data indicative of a load profile can be received. The load profile can specify one or more amounts of power to be delivered by an energy storage system over a duration. The energy storage system can include one or more energy storage elements of a first type and one or more energy storage elements of a second type. One or more time windows associated with high power events and one or more time windows associated with high energy events can then be determined based on the load profile. Power delivery by the energy storage elements of the first type and the energy storage elements of the second type can then be controlled based at least in part on the determined time windows.

Claims which contain your search:

1. A method of controlling an energy storage system, the method comprising: receiving, by one or more control devices, data indicative of a load profile specifying an amount of power to be delivered by an energy storage system over a duration, the energy storage system comprising one or more first energy storage elements of a first type, and one or more second energy storage elements of a second type; determining, by the one or more control devices, one or more first time windows in the duration when the load profile is associated with a high energy event and one or more second time windows in the duration when the load profile is associated with a high power event; and controlling, by the one or more control devices, power to be delivered by the energy storage system based at least in part on the one or more first time windows and the one or more second time windows.

2. The method of claim 1, wherein controlling, by the one or more control devices, power to be delivered by the energy storage system comprises controlling the one or more first energy storage elements to deliver more power relative to the second one or more energy storage elements during the one or more first time windows.

3. The method of claim 1, wherein controlling, by the one or more control devices, power to be delivered by the energy storage system comprises controlling the one or more second energy storage elements to deliver more power relative to the one or more first energy storage elements during the one or more second time windows.

4. The method of claim 1, wherein the one or more first energy storage elements comprise one or more molten salt battery devices.

5. The method of claim 1, wherein the one or more second energy storage elements comprise one or more lithium-ion battery devices.

6. The method of claim 1, wherein the energy storage system further comprises a plurality of switching elements, each switching element being selectively operable to control a charge or discharge current associated with at least one of the one or more first energy storage elements or the one or more second energy storage elements.

9. The method of claim 1, further comprising controlling, by the one or more control devices, power delivery by the energy storage system based at least in part on one or more operating parameters associated with the energy storage system.

10. The method of claim 9, wherein the one or more operating parameters comprise at least one of a temperature or a state of charge associated with the one or more energy storage elements of the first type or the one or more energy storage elements of the second type.

11. An energy storage system comprising: one or more first energy storage elements of a first type; one or more second energy storage elements of a second type; and a system controller communicatively coupled to the one or more first energy storage elements and the one or more second energy storage elements, the system controller comprising at least one processor and a non-transitory computer-readable medium storing instructions that, when executed by the at least one processor, cause the system controller to perform operations, the operations comprising:receiving data indicative of a load profile specifying an amount of power to be delivered by the energy storage system over a duration;determining one or more first time windows in the duration when the load profile is associated with a high energy event and one or more second time windows in the duration when the load profile is associated with a high power event; andcontrolling power delivery by the energy storage system based at least in part on the one or more first time windows and the one or more second time windows.

12. The energy storage system of claim 11, wherein controlling power delivery of the energy storage system comprises controlling the one or more first energy storage elements to deliver more power relative to the one or more second energy storage elements during the one or more first time windows.

13. The energy storage system of claim 11, wherein controlling power delivery of the energy storage system comprises controlling the one or more second energy storage elements to deliver more power relative to the one or more first energy storage elements during the one or more second time windows.

14. The energy storage system of claim 11, wherein the one or more first energy storage elements comprise one or more molten salt battery devices.

15. The energy storage system of claim 11, wherein the one or more second energy storage elements comprise one or more lithium-ion battery devices.

16. A system controller for controlling one or more first energy storage elements of a first type and one or more second energy storage elements of a second type in an energy storage system, the system controller comprising at least one processor and a non-transitory computer-readable medium storing instructions that, when executed by the at least one processor, cause the system controller to perform operations, the operations comprising: receiving data indicative of a load profile specifying an amount of power to be delivered by the energy storage system over a duration; determining one or more first time windows in the duration when the load profile is associated with a high energy event and one or more second time windows in the duration when the load profile is associated with a high power event; and controlling power delivery by the energy storage system based at least in part on the one or more first time windows and the one or more second time windows.

17. The system controller of claim 16, wherein controlling power delivery by the energy storage system comprises controlling the one or more first energy storage elements to deliver more power relative to the one or more second energy storage elements during the one or more first time windows.

18. The system controller of claim 16, wherein controlling power delivery by the energy storage system comprises controlling the one or more second energy storage elements to deliver more power relative to the one or more first energy storage elements during the one or more second time windows.

19. The system controller of claim 16, wherein the one or more first energy storage elements comprise one or more molten salt battery devices.

20. The system controller of claim 16, wherein the one or more second energy storage elements comprise one or more lithium-ion battery devices.


Patent
General Electric | Date: 2015-09-02

Systems and methods for controlling the temperature of an energy storage system are provided. More specifically, a time period of increased battery temperature attributable to, for instance, charging or discharging of the battery can be identified. A control system can be used to reduce the ambient temperature of a space associated with the battery energy storage devices in the time period prior to or immediately before the period of increased battery temperature. The ambient temperature can be maintained at a nominal ambient temperature at other times.

Claims which contain your search:

1. A method for regulating a temperature of an energy storage system, comprising: accessing, by one or more control devices, data associated with a battery charge profile for one or more battery energy storage devices; identifying, by the one or more control devices, a period of increased battery temperature from the battery charge profile; and controlling, by the one or more control devices, a thermal management system associated with the one or more battery energy storage devices based at least in part on the period of increased battery temperature to reduce the ambient temperature of a space associated with the one or more battery energy storage devices prior to the period of increased battery temperature.

2. The method of claim 1, wherein the period of increased battery temperature corresponds to a discharge period for the one or more battery energy storage devices.

3. The method of claim 1, wherein the period of increased battery temperature corresponds to a charge period for the one or more battery energy storage devices.

6. The method of claim 1, wherein the battery charge profile is a preset battery charge profile for the energy storage system.

7. The method of claim 1, wherein the battery charge profile is a predicted battery charge profile for the energy storage system.

9. The method of claim 1, wherein the method further comprises: receiving, by the one or more control devices, data indicative of one or more operating parameters of the one or more battery energy storage devices; determining, by the one or more control devices, data indicative of heat generation of the one or more battery energy storage devices based at least in part on the one or more operating parameters; and controlling, by the one or more control devices, the cooling system to provide increased cooling of the one or more battery energy storage devices based at least in part on the data indicative of heat generation.

11. The method of claim 9, wherein the one or more operating parameters comprises one or more of ambient temperature, battery temperature, current, or state of charge associated with the one or more battery energy storage devices.

12. A battery energy storage system, comprising: one or more battery energy storage devices; a cooling system configured to control an ambient temperature of a space associated with the one or more battery energy storage devices; and one or more control devices, the one or more control devices configured to identify a period of increased battery temperature and to control the cooling system to reduce the ambient temperature of a space associated with the one or more battery energy storage devices prior to the period of increased battery temperature.

13. The battery energy storage system of claim 12, wherein the period of increased battery temperature corresponds to a discharge period for the one or more battery energy storage devices.

14. The battery energy storage system of claim 12, wherein the period of increased battery temperature corresponds to a charge period for the one or more battery energy storage devices.

15. The battery energy storage system of claim 12, wherein the one or more control devices are configured to identify the period of increased battery temperature from a battery charge profile.

16. The battery energy storage system of claim 12, wherein the one or more battery energy storage devices comprises one or more of a sodium nickel chloride battery, sodium sulfur battery, lithium ion battery, or nickel metal hydride battery.

17. The battery energy storage system of claim 12, wherein the cooling system comprises one or more of a heating ventilation and cooling (HVAC) system, liquid cooling system, air handling unit, ventilation fan, or electrical cooling device.

18. The battery energy storage system of claim 12, wherein the battery energy storage system is part of a solar power generation system, wind power generation system, or gas turbine power generation system.

19. A control system for an energy storage system, the control system comprising one or more processors and one or more memory devices, the one or more memory devices storing computer-readable instructions that when executed by the one or more processers cause the one or more processors to perform operations, the operations comprising: receiving data indicative of one or more operating parameters associated with one or more battery energy storage devices; determining data indicative of increased heat generation of the one or more battery energy storage devices based at least in part on the one or more operating parameters using a model, the model specifying heat generation as a function of the one or more operating parameters; and controlling the cooling system to provide increased cooling of the one or more battery energy storage devices based at least in part on the data indicative of heat generation.

20. The control system of claim 19, wherein the operations further comprise: accessing data associated with a battery charge profile for one or more battery energy storage devices; identifying a period of increased battery temperature from the battery charge profile; and adjusting an ambient temperature set point based on the period of increased battery temperature to reduce the ambient temperature of a space associated with the one or more battery energy storage devices prior to the period of increased battery temperature.


Soloveichik G.L.,General Electric | Soloveichik G.L.,Advanced Research Projects Agency
Chemical Reviews | Year: 2015

There are several electrochemical technologies suitable for EES including supercapacitors, stationary batteries, regenerative fuel cells (RFCs), rechargeable metal-air batteries, and flow batteries. RFCs are usually combined with hydrogen storage and in some cases, such as space applications, with oxygen storage that adds cost but provides more power. The projected life of RFB systems is longer than that of conventional batteries, although it should be still verified in field tests. Combined with higher usable storage capacity of RFBs, it results in their lower levelized cost of electricity even when the capital cost is twice as much. They have less manufacturability issues due to the uniformity of electrolytes and cells. Independence of power and energy in RFBs allows for using the same chemistry in different applications. However, both fundamental and applied research is needed for industry acceptance and wide implementation of this technology in energy-storage systems. Computational models could save resources and time in scaling up and accurately predict the state of health and lifetime of an RFB for different applications. Research in these directions requires new breakthroughs and inventions but if successful it will enable an ideal RFB, which can cover the wide spectrum of stationary energy-storage applications using the same chemistry.

Document Keywords (matching the query): battery management systems, stationary energy storages, stationary batteries, energy storage systems, secondary batteries, electric batteries, conventional batteries, energy storage, electric energy storage, flow batteries, hydrogen storage.


Soloveichik G.L.,General Electric
Annual Review of Chemical and Biomolecular Engineering | Year: 2011

In recent years, with the deployment of renewable energy sources, advances in electrified transportation, and development in smart grids, the markets for large-scale stationary energy storage have grown rapidly. Electrochemical energy storage methods are strong candidate solutions due to their high energy density, flexibility, and scalability. This review provides an overview of mature and emerging technologies for secondary and redox flow batteries. New developments in the chemistry of secondary and flow batteries as well as regenerative fuel cells are also considered. Advantages and disadvantages of current and prospective electrochemical energy storage options are discussed. The most promising technologies in the short term are high-temperature sodium batteries with β″-alumina electrolyte, lithium-ion batteries, and flow batteries. Regenerative fuel cells and lithium metal batteries with high energy density require further research to become practical. © Copyright 2011 by Annual Reviews. All rights reserved.

Document Keywords (matching the query): high energy densities, renewable energy source, electrochemical energy storage, lithium ion battery, high energy physics, secondary battery, secondary batteries, redox flow batteries, sodium battery, energy storage, flow batteries, battery technology.


A battery energy storage system (1) is disclosed, the battery energy storage system (1) comprising a rechargeable battery assembly (3) for storing and providing energy and a protection system (19) including an arc flash protection device (26, 26) to protect against risks due to arc flashes. The arc flash protection device (26, 26) comprises an overcurrent protection unit (32) which detects overcurrent conditions indicating arc flash conditions in case of a low impedance of the battery assembly (3) and an undervoltage protection unit (33) which detects undervoltage conditions indicating arc flash conditions in case of a low impedance of the battery assembly (3), wherein upon detecting the overcurrent conditions and/or the undervoltage conditions for a predetermined minimum time period, the arc flash protection device (26, 26) initiates protective measures to prevent further operation of the battery assembly (3). An energy conversion system comprising such a battery energy storage system, which can be used for stationary and mobile energy supply or distribution applications, is also disclosed.

Claims which contain your search:

1. A battery energy storage system, comprising:a battery assembly (3) for storing and providing energy, wherein the battery assembly (3) is rechargeable;a protection system (19) comprising an arc flash protection device (26, 26) for protection against hazards from arc flashes, wherein the arc flash protection device (26, 26) is arrangedto sense a battery current (I_(B)) provided by the battery arrangement (3) and to compare it with a predefined maximum current threshold (I_(Bmax)),to sense a voltage (U_(B)) provided by the battery assembly (3) and to compare it with a predefined minimum voltage threshold (U_(Bmin)), andif the sensed battery current (I_(B)) is greater than the maximum current threshold (I_(Bmax)) and/or the sensed battery voltage (U_(B)) is smaller than the minimum voltage threshold (U_(Bmin)) to determine that arc flash conditions are present and to initiate protective measures to prevent further operation of the battery assembly (3).

2. A battery energy storage system according to claim 1, wherein the battery assembly (3) comprises at least one battery module (2) formed by a series connection of a plurality of battery cells (6), and preferably comprises a plurality of battery modules (2) connected in parallel.

3. A battery energy storage system according to claim 1 or 2, further comprising a positive DC voltage supply line (9) connected to a positive terminal (7) of the battery assembly (3) and a negative DC voltage supply line (12) connected to a negative terminal (8) of the battery assembly (3), wherein the positive and/or negative DC voltage supply line (9, 12) each comprises a controllable switch (14, 16) arranged therein for interruption of the line connection as required.

4. A battery energy storage system according to claim 3, further comprising a fuse (17, 18) in the positive and/or negative DC voltage supply line (9, 12) for interruption of the current flow therethrough as required in case of a high short-circuit current.

5. A battery energy storage system according to any preceding claim, further comprisinga current sensor (29) which senses the actual current (I_(B)) currently provided by the battery assembly (3) and provides a current signal representing the sensed actual current, anda voltage sensor (31) which senses actual voltage (U_(B)) currently provided by the battery assembly (2) and provides a voltage signal representing the sensed actual voltage.

6. A battery energy storage system according to any preceding claim, further comprising a battery management system (4) for monitoring and controlling the rechargeable battery assembly (3) and comprising a control device (22, 23) for determining the state of charge of the battery assembly (3) and for recognizing and preventing overcharge and over-discharge of the battery assembly (3).

7. A battery energy storage system according to claim 6, wherein the battery management system (4) is connected to a current sensor (29) and a voltage sensor (31) of the battery energy storage system (1) to receive from them signals representing present battery current (I_(B)) and present battery voltage (U_(B)), and wherein the control device (23) is arranged to compare the battery voltage signal received with a discharge voltage limit (U_(Blimit)) to recognize and prevent an over-discharged condition of the battery assembly (3).

8. A battery energy storage system according to claim 7, wherein the discharge voltage limit (U_(Blimit)) is higher than the minimum voltage threshold (U_(Bmin)), preferably at least one and half time as high as the minimum voltage threshold.

9. A battery energy storage system according to any of claims 6 to 8, wherein the arc flash protection device (26, 26) is part of the battery management system (4).

10. A battery energy storage system according to any preceding claim, wherein the arc flash protection device (26, 26) is arranged to measure a first time duration (t_(1)) during which the sensed battery current (I_(B)) is greater than the maximum current threshold (I_(Bmax)) and a second time duration (t_(2)) during which the sensed battery voltage (U_(B)) is smaller than the minimum voltage threshold (U_(Bmin)) and to initiate protective measures if the first time duration (t_(1)) exceeds a first maximum time threshold (T_(max1)) and/or the second time duration (t_(2)) exceeds a second maximum time threshold (T_(max2)).

11. A battery energy storage system according to claim 10, wherein the first maximum time threshold (T_(max1)) is lower than the second maximum time threshold (T_(max2)).

12. A battery energy storage system according to claim 10 or claim 11, wherein the second maximum time threshold (T_(max2)) is lower than a discharge time limit (T_(limit)) indicating the time period during which the battery voltage (U_(B)) must be below the discharge voltage limit (U_(Blimit)) to ensure that an over-discharged condition of the battery assembly is recognized.

13. A battery energy storage system according to any preceding claim, wherein the arc flash protection device (26, 26) is arrangedto compare the sensed battery voltage (U_(B)) with a predefined first minimum voltage threshold and with a predefined second minimum voltage threshold which is lower than the first minimum voltage threshold; andif the sensed battery voltage (U_(B)) is below the first minimum voltage threshold for a first time period or if the sensed battery voltage is below the second minimum voltage threshold for a second period shorter than the first period to initiate protective measures to prevent further operation of the battery assembly (3).

14. An energy conversion system, comprising:a battery assembly (3) for storing and providing energy, wherein the battery assembly (3) is rechargeable;a converter device (36) connected to the battery assembly (3) via a DC link (40) for converting input side DC voltage energy provided by the battery assembly (3) into output side AC voltage energy or vice versa; anda protection system (19, 51) comprising an arc flash protection device (26, 26) for protection against hazards from arc flashes, wherein the arc flash protection device (26, 26) is arrangedto sense a battery current (I_(B)) provided by the battery arrangement (3) and to compare it with a predefined maximum current threshold (I_(Bmax)),to sense a voltage (U_(B)) provided by the battery assembly (3) and to compare it with a predefined minimum voltage threshold (U_(Bmin)), andif the sensed battery current (I_(B)) is greater than the maximum current threshold (I_(Bmax)) and/or the sensed battery voltage (U_(B)) is smaller than the minimum voltage threshold (U_(Bmin)) to determine that arc flash conditions are present and to initiate protective measures to prevent further operation of the battery assembly (3).

15. A method for protecting a battery energy storage system against hazards from arc flashes, wherein the battery energy storage system comprises a rechargeable battery assembly for storing and providing DC voltage energy, the method comprising the steps of:sensing a battery current provided by the battery assembly and delivering a battery current signal indicative thereof;comparing the battery current signal with a predefined maximum current threshold;sensing a battery voltage provided by the battery assembly and delivering a battery voltage signal indicative thereof;comparing the battery voltage signal with a predefined minimum voltage threshold; andin case that the battery current signal is greater than the maximum current threshold for a first minimum time duration and/or the battery voltage signal is smaller than the minimum voltage threshold for a second minimum time duration determining that arc flash conditions are present and initiating protection measures to prevent further operation of the battery assembly.


A battery energy storage system is disclosed, the battery energy storage system comprising a rechargeable battery assembly for storing and providing energy and a protection system including an arc flash protection device to protect against risks due to arc flashes. The arc flash protection device comprises an overcurrent protection unit which detects overcurrent conditions indicating arc flash conditions in case of a low impedance of the battery assembly and an undervoltage protection unit which detects undervoltage conditions indicating arc flash conditions in case of a low impedance of the battery assembly, wherein upon detecting the overcurrent conditions and/or the undervoltage conditions for a predetermined minimum time period, the arc flash protection device initiates protective measures to prevent further operation of the battery assembly. An energy conversion system comprising such a battery energy storage system, which can be used for stationary and mobile energy supply or distribution applications, is also disclosed.

Claims which contain your search:

1. A battery energy storage system, comprising: a battery assembly for storing and providing energy, wherein the battery assembly is rechargeable; and a protection system comprising an arc flash protection device for protection against hazards from arc flashes, wherein the arc flash protection device is arranged:to sense a battery current provided by the battery arrangement and to compare it with a predefined maximum current threshold,to sense a voltage provided by the battery assembly and to compare it with a predefined minimum voltage threshold, andif the sensed battery current is greater than the maximum current threshold and/or the sensed battery voltage is smaller than the minimum voltage threshold, to determine that arc flash conditions are present and to initiate protective measures to prevent further operation of the battery assembly.

2. The battery energy storage system according to claim 1, wherein the battery assembly comprises at least one battery module formed by a series connection of a plurality of battery cells.

3. The battery energy storage system according to claim 1, further comprising a positive DC voltage supply line connected to a positive terminal of the battery assembly and a negative DC voltage supply line connected to a negative terminal of the battery assembly, wherein the positive and/or negative DC voltage supply line each comprises a controllable switch arranged therein for interruption of the line connection as required.

4. The battery energy storage system according to claim 1, further comprising: a current sensor which senses the actual current currently provided by the battery assembly and provides a current signal representing the sensed actual current; and a voltage sensor which senses actual voltage currently provided by the battery assembly and provides a voltage signal representing the sensed actual voltage.

5. The battery energy storage system according to claim 1, further comprising a battery management system for monitoring and controlling the rechargeable battery assembly and comprising a control device for determining the state of charge of the battery assembly and for recognizing and preventing overcharge and over-discharge of the battery assembly.

6. The battery energy storage system according to claim 5, wherein the battery management system is connected to a current sensor and a voltage sensor of the battery energy storage system to receive from them signals representing present battery current and present battery voltage, and wherein the control device is arranged to compare the battery voltage signal received with a discharge voltage limit to recognize and prevent an over-discharged condition of the battery assembly.

7. The battery energy storage system according to claim 6, wherein the discharge voltage limit is higher than the minimum voltage threshold.

8. The battery energy storage system according to claim 5, wherein the arc flash protection device is part of the battery management system.

9. The battery energy storage system according to claim 3, further comprising a fuse in the positive and/or negative DC voltage supply line for interruption of the current flow therethrough as required in case of a high short-circuit current.

10. The battery energy storage system according to claim 1, wherein the arc flash protection device is arranged to measure a first time duration during which the sensed battery current is greater than the maximum current threshold and a second time duration during which the sensed battery voltage is smaller than the minimum voltage threshold and to initiate protective measures if the first time duration exceeds a first maximum time threshold and/or the second time duration exceeds a second maximum time threshold.

11. The battery energy storage system according to claim 10, wherein the first maximum time threshold is lower than the second maximum time threshold.

12. The battery energy storage system according to claim 10, wherein the second maximum time threshold is lower than a discharge time limit indicating the time period during which the battery voltage must be below the discharge voltage limit to ensure that an over-discharged condition of the battery assembly is recognized.

13. The battery energy storage system according to claim 1, wherein the arc flash protection device is arranged: to compare the sensed battery voltage with a predefined first minimum voltage threshold and with a predefined second minimum voltage threshold which is lower than the first minimum voltage threshold; and if the sensed battery voltage is below the first minimum voltage threshold for a first time period or if the sensed battery voltage is below the second minimum voltage threshold for a second period shorter than the first period, to initiate protective measures to prevent further operation of the battery assembly.

14. An energy conversion system, comprising: a battery assembly for storing and providing energy, wherein the battery assembly is rechargeable; a converter device connected to the battery assembly via a DC link for converting input side DC voltage energy provided by the battery assembly into output side AC voltage energy or vice versa; and a protection system comprising an arc flash protection device for protection against hazards from arc flashes, wherein the arc flash protection device is arranged:to sense a battery current provided by the battery arrangement and to compare it with a predefined maximum current threshold;to sense a voltage provided by the battery assembly and to compare it with a predefined minimum voltage threshold; andif the sensed battery current is greater than the maximum current threshold and/or the sensed battery voltage is smaller than the minimum voltage threshold, to determine that arc flash conditions are present and to initiate protective measures to prevent further operation of the battery assembly.

15. The energy conversion system according to claim 14, wherein the battery assembly comprises a plurality of battery modules each having a plurality of battery cells connected in series, wherein the battery modules are connected in parallel to each other and to a common DC bus to which the DC link is coupled.

16. The energy conversion system according to claim 14, further comprising one or more of the following protection devices for protection against fault currents: a controllable switch in a positive and/or negative DC voltage supply line, which is connected to a positive and negative terminal of the battery assembly, respectively, to enable interruption of the current flow therethrough as required; a fuse in the positive and/or negative DC voltage supply line for interruption of the current flow as required in case of a high short-circuit current; a ground fault circuit interrupter in a ground connection between a positive or negative connecting line coupling the DC link with the positive and negative DC voltage supply line, respectively, and a grounding point; overvoltage protectors provided on the DC side and/or the AC side of the converter device for surge protection; and circuit breakers arranged in the connecting lines of the converter device on the DC side and/or the AC side to interrupt same as required.

17. The energy conversion system according to claim 14, further comprising a battery management system for monitoring and controlling the rechargeable battery assembly and comprising a control device for determining the state of charge of the battery assembly and for recognizing and preventing overcharge and over-discharge of the battery assembly.

18. The energy conversion system according to claim 17, wherein the arc flash protection device is part of the battery management system or is separate from the battery management system.

19. The energy conversion system according to claim 14, wherein the arc flash protection device is arranged to measure a first time duration during which the sensed battery current is greater than the maximum current threshold and a second time duration during which the sensed battery voltage is smaller than the minimum voltage threshold and to initiate protective measures if the first time duration exceeds a first maximum time threshold and/or the second time duration exceeds a second maximum time threshold wherein the first maximum time threshold is lower than the second maximum time threshold.

20. A method for protecting a battery energy storage system against hazards from arc flashes, wherein the battery energy storage system comprises a rechargeable battery assembly for storing and providing DC voltage energy, the method comprising: sensing a battery current provided by the battery assembly and delivering a battery current signal indicative thereof; comparing the battery current signal with a predefined maximum current threshold; sensing a battery voltage provided by the battery assembly and delivering a battery voltage signal indicative thereof; comparing the battery voltage signal with a predefined minimum voltage threshold; and in case that the battery current signal is greater than the maximum current threshold for a first minimum time duration and/or the battery voltage signal is smaller than the minimum voltage threshold for a second minimum time duration, determining that arc flash conditions are present and initiating protection measures to prevent further operation of the battery assembly.


Patent
General Electric | Date: 2015-07-01

Systems and methods for controlling the state of charge of an energy storage system used in conjunction with a renewable energy source or other power generation system are provided. More particularly, a future output requirement of the energy storage system can be predicted based at least in part on data indicative of anticipated conditions, such as weather conditions, wake conditions, or other suitable conditions. A control system can adjust a state of charge setpoint from a nominal setpoint (e.g. 50%) to an adjusted setpoint based at least in part on the future output requirement. In this way, the energy storage system can better accommodate the output requirements of the energy storage system during varying weather conditions.

Claims which contain your search:

1. A method for controlling an energy storage system associated with a power generation system, comprising: accessing, by one or more control devices, data indicative of anticipated conditions for a predetermined time period; determining, by the one or more control devices, a future output requirement of the energy storage system for the predetermined time period based at least in part on the data indicative of the anticipated weather conditions; adjusting, by the one or more control devices, a state of charge setpoint for the energy storage system based at least in part on the future output requirement; and controlling, by the one or more control devices, the delivery of power to or from the energy storage system based at least in part on the state of charge setpoint.

4. The method of claim 3, wherein the adjusted setpoint is greater than the nominal setpoint when the future output requirement is determined to be increased relative to a current output requirement of the energy storage system.

5. The method of claim 1, wherein controlling, by the one or more control devices, the delivery of power to or from the energy storage system comprises: receiving, by the one or more computing devices, a signal indicative of the current state of charge of the energy storage system; and generating, by the one or more computing devices, a power command for the power generation system based at least in part on the signal indicative of the current state of charge of the energy storage system and the state of charge setpoint.

6. The method of claim 5, wherein the power command is determined based at least in part on a maximum output power for the power generation system when the state of charge setpoint is greater than the current state of charge of the energy storage system.

7. The method of claim 1, wherein controlling, by the one or more control devices, the delivery of power to or from the energy storage system comprises delivering power generated by the power generation system that is in excess of an output power requirement for the power generation system during the predetermined time period to the energy storage system to increase the state of charge of the energy storage system.

10. The method of claim 8, wherein the energy storage system comprises a battery energy storage system.

11. A control system for controlling an energy storage system associated with a renewable energy system, the control system comprising: a state of charge adjustment module implemented by one or more control devices, the state of charge adjustment module configured to adjust a state of charge setpoint for the energy storage system based at least in part on data indicative of anticipated weather conditions; a renewable energy control module implemented by the one or more control devices, the renewable energy control module configured to generate a power command for the renewable energy system based at least in part on the state of charge setpoint and a current state of charge for the energy storage system; and a charge control module implemented by the one or more control devices, the charge controller configured to control the delivery of power to or from the energy storage system based at least in part on the state of charge setpoint.

12. The control system of claim 11, wherein the state of charge adjustment module is configured to adjust the state of charge setpoint to accommodate a future output requirement of the energy storage system.

13. The control system of claim 12, wherein the state of charge adjustment module is configured to adjust the state of charge setpoint from a nominal setpoint to an adjusted setpoint, the adjusted setpoint being greater than the nominal setpoint when the future output requirement of the energy storage system is greater than a current output requirement of the energy storage system.

14. The control system of claim 11, wherein the renewable energy control module is configured to generate the power command based at least in part on a maximum output power for the renewable energy system when the state of charge setpoint is greater than the current state of charge of the energy storage system.

15. A wind turbine system, comprising: a wind driven generator; a power converter coupled to the wind driven generator, the power converter comprising a DC bus; a battery energy storage system coupled to the DC bus of the power converter, the battery energy storage system comprising one or more battery cells; a control system configured to control the delivery of power to or from the battery energy storage system based at least in part on a state of charge setpoint; wherein the control system is configured to adjust the state of charge setpoint for the battery energy storage system based at least in part on data indicative of anticipated weather conditions for a predetermined time period.

16. The wind turbine system of claim 15, wherein the control system is configured to adjust the state of charge setpoint to accommodate a future output requirement of the battery energy storage system during the predetermined time period, the future output requirement being determined based at least in part on the data indicative of anticipated weather conditions.

19. The wind turbine system of claim 15, wherein the control system is configured to control energy production by the wind driven generator based at least in part on a maximum output power for the wind driven generator when a current state of charge of the battery energy storage system is less than the state of charge setpoint.

20. The wind turbine system of claim 15, wherein the control system is configured to deliver power generated by the wind generator that is in excess of an output power requirement for the renewable energy system during the predetermined time period to the battery energy storage system to increase the state of charge of the battery energy storage system


A system for operating a power generation system 100 within a battery storage/discharge mode includes a power convertor 162 having a DC link 126, 136, a switching module 142 coupled to the DC link, a storage device 144, and a filter coupled between the storage device 144 and power converter 162. The filter may correspond to a normal mode filter configured to limit normal mode voltage from being applied to the storage device 144. A common mode filter may be associated with the storage device 144. The storage device 144 may correspond to one or more batteries 143 while the power generation system 100 may correspond to a wind-driven generator 120.

Claims which contain your search:

1. A system for operating a power generation system (100) within an energy storage/discharge mode, the system comprising:a power convertor (162) including a DC link (126, 136);a switching module (142) coupled to said DC link (126, 136);an energy storage device (144); anda filter coupled between said switching module (142) and said energy storage device (144),wherein said filter comprises a normal mode filter having a series coupled inductor and capacitor (138) corresponding to an inductor leg and a capacitor leg, andwherein said inductor leg is coupled to said power converter (162) and said capacitor leg is coupled to said DC link (126, 136).

2. The system of claim 1, wherein said switching module is configured as a bi-directional DC-to-DC converter for controlling the flow of power to and from said energy storage device (144).

3. The system of any preceding claim, wherein said energy storage device (144) comprises at least one battery (143).

4. The system of any preceding claim, wherein said energy storage device (144) comprises a plurality of batteries (143).

5. The system of claim 4, wherein said plurality of batteries (143) are coupled in parallel.

6. The system of any preceding claim, further comprising a second filter associated with said energy storage device (144).

11. A wind turbine system (100), comprising:a wind-driven generator;a power convertor (162) including a DC link (126, 136) associated with said wind-driven generator;a switching module coupled to said DC link;an energy storage device (144); anda filter coupled between said switching module and said energy storage device (144),wherein said filter comprises a normal mode filter having a series coupled inductor and capacitor (138) corresponding to an inductor leg and a capacitor leg, andwherein said inductor leg is coupled to said power converter and said capacitor leg is coupled to said DC link (126, 136).

12. The system (100) of claim 11, wherein the switching module is configured to be operated as a bi-directional DC-to-DC converter for controlling the flow of power to and from said energy storage device (144).

14. A method for operating a power generation system within an energy storage/discharge mode, the power generation system including a power convertor (162) having a DC link (126, 136), the power generation system further including a switching module coupled to the DC link and an energy storage device (144), the method comprising:controlling the operation of the switching module such that power is directed between the DC link (126, 136) and the energy storage device (144); andtransmitting the power through a filter coupled between the DC link (126, 136) and the energy storage device (144), the filter comprising a normal mode filter having a series coupled inductor and capacitor (138) corresponding to an inductor leg and a capacitor leg, the inductor leg being coupled to the switching module and the capacitor leg being coupled to the DC link (126, 136).

15. The method of claim 14, wherein the filter is a first filter, further comprising transmitting the power through a second filter coupled between the DC link (126, 136) and the energy storage device (144), the second filter being configured as a common mode filter.

Loading General Electric collaborators
Loading General Electric collaborators