Chongqing Electric Power Research Institute and Mianyang Gocreat Technology Co. | Date: 2015-05-27
An electricity meter verification robot including: a chassis (A); an electricity meter turnover box-picking and placing mechanism (B) provided on the chassis (A) for picking and placing an electricity meter turnover box; a mechanical hand (D) for picking, placing and verifying an electricity meter; and a mechanical arm (C) provided on the chassis (A) for controlling a position of the mechanical hand (D). The mechanical hand (D) is arranged at an end of the mechanical arm (C) away from the chassis (A). The electricity meter turnover box is placed on the chassis (A) by the electricity meter turnover box-picking and placing mechanism (B), then the mechanical hand (D) is controlled by the mechanical arm (C) such that the electricity meter is taken out of the electricity meter turnover box and is placed on the electricity meter verification station for being verified, and the electricity meter is placed back into the electricity meter turnover box after the verification. With the electricity meter verification robot, the electricity meter is automatically picked, placed and verified, thereby the speed of the verifying of the electricity meter is improved effectively, and the labor intensity is reduced, therefore the working efficiency is improved.
Chongqing Electric Power Research Institute, State Grid Corporation of China and The Smartech Institute | Date: 2015-08-22
The present application provides a method and a system for detecting data of an instrument. The method comprises controlling rotation of the current data image in a first direction and acquiring current projection values of a pointer of the instrument in a vertical direction from the current data image after acquiring a current data image from an instrument to be read; then, selecting a maximum projection value from the acquired projection values and determining a corresponding position of the pointer of the instrument as a position to be calculated; calculating a first rotation angle required by rotation of the pointer of the instrument to the position to be calculated; substituting the first rotation angle into a pre-stored first calculation formula and calculating a first angle between the pointer of the instrument and the position to be calculated; then, substituting the first angle into a formula of correspondence between a pre-stored angle between the pointer of the instrument and the position to be calculated and instrument graduations to calculate current instrument data of the instrument to be read, thus ensuring the accuracy of the resulting data under various conditions.
State Grid Corporation of China and Chongqing Electric Power Research Institute | Date: 2013-10-09
A method for on-line diagnosing gradually-changing fault of electronic current transformers comprises the following steps collecting output signals of electronic transformers of a whole transformer substation, calculating theoretical instantaneous values of the current at the tail ends of power transmission lines and on secondary sides of transformers at every moment, comparing the theoretical instantaneous values with the corresponding collected values, calculating residual errors of the electronic current transformers at the head and tail ends of each power transmission line and the primary and the secondary sides of each transformer respectively, judging whether gradually-changing fault occurs with the electronic current transformers by comparing the residual errors with preset threshold values, and simultaneously performing Kirchhoff detection by injecting current into a busbar to position a fault transformer.
State Grid Corporation of China and Chongqing Electric Power Research Institute | Date: 2013-09-02
The present application provides a power line communications system and method. The system comprises a power line network, a sending apparatus, and a receiving apparatus. The receiving apparatus comprises at least two PLC modems connected through a power line link. The sending apparatus sends a signal to a target PLC modem in the receiving apparatus through a power line network. The target PLC modem is at least one PLC modem in the receiving apparatus. The PLC modems in the receiving apparatus simultaneously receive a signal, the PLC modems except the target PLC modem respectively send the received signal to the target PLC modem through a wireless link, and the target PLC modem restores the signal sent by the sending apparatus according to the signal received through the power line network and the signal received through the wireless link. According to the power line communications system and method provided in the present application, the signal transmission quality is improved, and the data transmission rate and the system reliability are improved.
Chongqing Electric Power Research Institute and State Grid Corporation of China | Date: 2014-09-10
A method for controlling charging and discharging of an electric vehicle, the method comprising: first, analyzing information such as the battery status and the history default rate of electric vehicles applying for joining a power-grid charging and discharging service, and screening out an electric vehicle that can participate in the charging and discharging service for electric vehicles in the future; then, determining an optimal combination state of a generator set and the electric vehicle by using a method of electric energy transmission cost comparison; and further monitoring in real time the status of the electric vehicle during charging and discharging, and performing real-time power control on the electric vehicle, whereby an electric vehicle aggregator not only can meet the requirements on the charging and discharging service of the power system, but also can implement energy management and real-time control of the electric vehicles during charging and discharging, thereby reducing the effect of charging and discharging on the vehicle-mounted power battery.
Chongqing Electric Power Research Institute and State Grid Corporation of China | Date: 2014-10-23
A grounding grid breakpoint diagnostic method for a transient electromagnetic method, based on a transient electromagnetic detection apparatus. The method comprises: (101) disposing a test line at a position above a grounding grid to be diagnosed on the ground, and determining coordinates of a detection point; (102) obtaining information about coordinates of the detection point, and coinciding the center of the transient electromagnetic detection apparatus with the coordinates of the detection point; (103) performing, by the transient electromagnetic detection apparatus, measurement along the test line point by point, so as to obtain measurement data; (104) processing, by using diagram forming software, the measurement data to form a longitudinal resistivity cross-section diagram of the detection point according to a preset formula; (105) determining whether a breakpoint occurs at the detection point according to the longitudinal resistivity cross-section diagram. The method does not depend on a design material of a grounding grid, and can implement non-excavation grounding grid breakpoint diagnosis without outage, thereby reducing economic losses in a diagnosis process.
Chongqing Electric Power Research Institute and State Grid Corporation of China | Date: 2012-10-22
A cogeneration unit and wind power joint heating system and a scheduling method therefor. The joint heating system comprises a coal-fired steam-extraction condensing-steam cogeneration unit (A), a wind turbine generator unit (B), an air conditioner heat pump (108) parallel-connected to the coal-fired steam-extraction condensing-steam cogeneration unit (A) and to the wind turbine generator unit (B) via a power cable network (113), and a hot water heating radiator (110) connected to the coal-fired steam-extraction condensing-steam cogeneration unit (A) via a heating pipe network (114). The joint heating system also comprises an integrated scheduling control device (115), a first remote centralized controller (1121), a second remote centralized controller (1122), and a third remote centralized controller (1123). Heating is provided to a user by the hot water heating radiator (110) and the air conditioner heat pump (108); while electricity is provided jointly by the coal-fired steam-extraction condensing-steam cogeneration unit (A) and the wind turbine generator unit (B). The scheduling method comprises: after detecting over a period of time the state of power supply and the state of power consumption of the user via the integrated scheduling control device (115), making a prediction for an upcoming period of time, and then scheduling on this basis. Under the premise of ensuring electricity supply and heat supply, the scheduling method reduces hot water flow outputted for heating, and compensates with electricity heating.
State Grid Corporation of China, Chongqing Electric Power Research Institute and Chongqing University | Date: 2014-03-04
The application discloses a method for acquiring parameters of a dynamic signal, including: selecting a dynamic sample signal sequence of a power grid to constitute an autocorrelation matrix; determining an effective rank of the autocorrelation matrix and the number of frequency components of the dynamic sample signal sequence; establishing an AR model, and solving a model parameter of the AR model; determining an expression and a complex sequence of the dynamic sample signal sequence by using a Prony algorithm, wherein the dynamic sample signal sequence is represented by the complex sequence with a minimum square error; and substituting a root of a characteristic polynomial corresponding to the model parameter into the complex sequence and solving various parameters of the dynamic sample signal sequence. In the application, with the idea of AR parameter model, a current signal is considered to be a linear combination of signals at previous time points.
Zhang J.,Zhejiang University |
Liao J.,Chongqing Electric Power Research Institute |
Wang J.,Zhejiang University |
Qian Z.,Zhejiang University
IEEE Transactions on Power Electronics | Year: 2012
This paper proposes a current-driving scheme for a synchronous rectifier (SR) in an LLC resonant converter with a voltage-doubler rectifier. In the proposed scheme, only one current transformer (CT) with one secondary winding is used to drive two SRs in the voltage-doubler rectifier. Also, the sensed current from the CT can be fed to the output with an energy-recovery circuit. Compared to the conventional center-tapped rectifier, the CT count for the SR drive circuit is reduced, which saves both cost and space. Although the current rating of the SR in the voltage-doubler rectifier is doubled, the voltage rating is well reduced and a lower voltage rating device with lower ON-state resistance can be used to compensate the increased current rating. Furthermore, the SR voltage stress is well clamped to the output voltage under any condition which improves the reliability of the circuit. A prototype with 16V/5.6A output was built to verify the theoretical analysis. © 2011 IEEE.
Chongqing Electric Power Research Institute | Date: 2011-11-09
A holographic detection device for a content of a gas in a GIS switch includes a laser and a data process system. The laser includes a laser emitter and a laser receiver which are fixed at a sampling port of the GIS switch and connected with the data process system. A holographic detection method for a content of a gas in a GIS switch includes emitting a laser beam towards the inside of the GIS switch; receiving the laser beam from the inside of the GIS switch, and calculating a content of hydrogen fluoride gas inside the GIS switch according to an intensity of the emitted laser beam and an intensity of the received laser beam. Since the laser beam goes through the inside of the GIS switch, there is a small error in the detection result, which thus can reflect a real state inside the GIS switch.