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Sharaf A.M.,Sharaf Energy Systems Inc. | Sahin M.E.,Recep Tayyip Erdoğan University
IETE Technical Review (Institution of Electronics and Telecommunication Engineers, India) | Year: 2016

This paper presents a new design for a low-impact, fully controlled, and flexible self-adjusting DC side pulse-width modulation (PWM)-hybrid modulated filter compensation (HMFC) scheme for multi photovoltaic-arrays utilized for vehicle-to-grid battery-charging electric vehicle schemes. The flexible HMFC scheme developed by the first author as a member of dynamic hybrid capacitor compensation and filtering scheme is robust and effective as it ensures maximum energy utilization and low inrush current transients. In addition, it provides transient voltage damping for a stabilized common DC interface bus to the battery charger. The new flexible controller uses a regulated multi-loop error-driven, error-scaled, and de-coupled hybrid mode charging controller for the PWM switching scheme along with two MOSFET/IGBT (Metal Oxide Semiconductor Field Effect Transistor/Insulated Gate Bipolar Transistor) complementary switches based on ratings and are cascaded for proper voltage and current photovoltaic (PV) arrays utilized. The dynamic error-driven controller ensures reduction in inrush current and transient voltage conditions as well as compensation for cloudy and shadowy conditions by equalizing the maximum power utilization of the two PV arrays. This will ensure efficient PV solar-system energy utilization as well as fully de-coupled source-load operation for the new proposed multi modal Li-ion battery-charging controller. The multi-regulator error-driven proportional integrated derivative controllers with newly added acceleration and fast response auxiliary loops ensure efficient fast charging as well as common DC-bus stabilization under load excursions, temporary faults, and battery hybrid voltage-current-power (V-I-P) charging modes. The hybrid switched/modulated capacitive-filter compensator ensures limited current excursions for transient DC voltage conditions. © 2016 IETE


Sharaf A.M.,Sharaf Energy Systems Inc. | Khaki B.,Amirkabir University of Technology
INISTA 2012 - International Symposium on INnovations in Intelligent SysTems and Applications | Year: 2012

This paper presents a novel hybrid series-parallel switched/modulated FACTS-based filter/compensation scheme (SCC) developed by the First Author for smart grid applications. The proposed FACTS filter/compensation device comprises a hybrid series and shunt switched capacitor-banks controlled by a dynamic time decoupled multi-regulator multi-loop error driven inter-coupled Weighted-Modified PID (WMPID) controller. The effectiveness of the proposed low cost Pulse Width Modulated (PWM) scheme is validated using MATLAB-Simulink digital simulation results. The coordinated dynamic controller ensures FACTS device effectiveness in limiting inrush current conditions, enhancing bus voltage stabilization, improving feeder voltage regulation, reducing total harmonic distortion, and enhancing power factor at both source and load buses. The unified AC system was validated for both normal operation and load change conditions. © 2012 IEEE.


Sharaf A.M.,Sharaf Energy Systems Inc. | Aktaibi A.A.,Memorial University of Newfoundland
INISTA 2012 - International Symposium on INnovations in Intelligent SysTems and Applications | Year: 2012

This This paper presents a novel dynamic based Stabilization Scheme and Smart-Stabilization Coordinated Control strategy developed by the First Author for a hybrid micro grid Village Electricity Integrated Utilization Scheme using Photovoltaic PV, Fuel Cell FC, wind Turbine and backup Diesel generation renewable generation system. The Proposed Micro Grid is fully interfaced using a Common fully stabilized Collection Bus. The scheme is fully stabilized using a novel based Filter Compensation Scheme (FCS) ensuring that the diesel generator set is only utilized when the demand electric energy exceeds the aggregate PV, FC and the Wind Turbine total energy capacity within specified operational levels to ensure highest efficient operation of the renewable energy sources with the backup diesel engine. The novel Smart Dynamic Error Driven Variable Structure-Sliding Mode Controller is used for the - Modulated Filter Compensator with a PI - controller for efficient utilization of the Back-Up Diesel Gen-Set ensure the objectives of a safe decoupled interface with maximum green energy utilization and enhanced power quality of the hybrid renewable energy scheme. The Hybrid Scheme is validated using Mat lab/Simulink Software Environment. © 2012 IEEE.


Abdelsalam A.A.,Suez Canal University | Sharaf A.M.,Sharaf Energy Systems Inc.
International Conference on Smart Energy Grid Engineering, SEGE 2015 | Year: 2015

This paper proposes a novel custom power device based on distribution static compensator (DSTATCOM) with PID controller driven by the unified error signal (UES) from a multi loop dynamic error controller scheme. Both DSTATCOM and UES are modified to meet the requirements for voltage stabilization, voltage waveform disturbance compensation and power factor improvement. A complete simulation model of the proposed system is developed in Matlab/Simulink Environment. The system is simulated with different control strategies under different operating conditions for comparison. The controllers and the control strategies are developed to have the novel DSTATCOM be operated for voltage stabilization, power factor improvement, energy losses reduction, power quality, and less harmonics distortion. The operational characteristics of a power system, supplying electrical power to hybrid loads consisting of linear and nonlinear and motorized loads, are investigated for better performance and higher power quality employing the proposed DSTATCOM and UES driven controllers. © 2015 IEEE.


Sharaf A.M.,Sharaf Energy Systems Inc. | Gandoman F.H.,University of Kurdistan
International Conference on Smart Energy Grid Engineering, SEGE 2015 | Year: 2015

The paper presents a Shunt Filter Compensator-FACTS DVS/Green Plug filter/Dynamic Voltage Stabilization device developed by the First Author as a new member of Switched/Modulated Shunt LC Compensation devices for Dynamically Modulating AC Bus Admittance for stabilized and efficient energy transfer utilization, Dynamic Voltage stabilization DVS- for nonlinear loads on smart grid is required as the grid network becomes weak and insecure, especially with new Distributed Generation (DG) interface and use of Wind/Photovoltaic and battery storage systems. The FACTS-DVS/GP is validated using MATLAB-Simulink Digital Simulation Environment varying load and system conditions including open circuit and short circuit fault conditions and load-excursions/ load reductions. The coordinated, multi-regulation, inter coupled dynamic controller scheme ensures the FACTS-DVS/GP device effectiveness in improving system security, energy utilization, power factor, power quality at key AC Buses, while reducing inrush currents and transient over-voltage/switching Recovery Voltage excursions. Hence, improving dynamic voltage stabilization, feeder regulation and power quality/factor enhancement. © 2015 IEEE.


Ozkop E.,Karadeniz Technical University | Sharaf A.M.,Sharaf Energy Systems Inc. | Altas I.H.,Karadeniz Technical University
Turkish Journal of Electrical Engineering and Computer Sciences | Year: 2016

This paper introduces an adaptive fuzzy PI controller (AFPIC) for a exible AC transmission system (FACTS)- based dynamic power filter (DPF) to be used in wave energy conversion systems. The new FACTS device stabilizes the DC-common bus voltage, reduces quality of power troubles, and enhances energy utilization by acting as a bus quantity enhancer (BQE). The design and realization of the proposed FACTS-based DPF and efficient control schemes are fully studied. To validate the efficiency of the proposed BQE FACTS device, a digital simulation model and a laboratory test system are developed in the MATLAB/Simulink/Simpower software environment for comparison. Various experimental test models of the proposed BQE system and dynamic error-based controller structures have been utilized to verify the simulation results. It has been shown that the utilization of the proposed AFPIC with the novel BQE device and multivariable error driven control strategy is very effective to eliminate stochastic wave inuences on voltage on the load side and load variations on the source side by decreasing voltage sag and swells. The effectiveness of the BQE is also tested by applying error energy-based performance indices ISE, IAE, and ITAE. © 2016 Tübitak.


Abdelsalam A.A.,Suez Canal University | Desouki M.E.,King Abdulaziz University | Sharaf A.M.,Sharaf Energy Systems Inc.
Journal of Electrical Systems | Year: 2013

This paper presents a novel modulated power filter compensator (MPFC) scheme for the smart grid stabilization and efficient utilization. The MPFC is controlled by a novel tri-loop dynamic error driven inter coupled modified VSC controller. The Matlab digital simulation models of the proposed MPFC scheme has been fully validated for effective power quality (PQ) improvement, voltage stabilization, power factor correction and transmission line loss reduction. The proposed FACTS based scheme can be extended to distributed/dispersed renewable energy interface and utilization systems and can be easily modified for other specific stabilization, compensation requirements, voltage regulation and efficient utilization. © JES 2013.


Norouzi M.R.,Islamic Azad University | Ahmadi A.,Islamic Azad University at Science and Research of Fars | Sharaf A.M.,Sharaf Energy Systems Inc. | Esmaeel Nezhad A.,Islamic Azad University at Najafabad
Electric Power Systems Research | Year: 2014

This paper proposes a new technique based on lexicographic optimization and ε-constraint method to solve the combined economic emission scheduling problem of hydrothermal systems comprising several equality constraints as well as non-equality ones. The hydrothermal scheduling problem is modeled as a multi-objective problem with two objective functions as fuel cost minimization and also pollutant emission minimization. After deriving the Pareto set, the most preferred solution is determined using a fuzzy satisfying method. The thermal plants are considered with valve point effect and emission level function. Besides, this paper has taken into consideration the multi-reservoir cascaded configuration of hydro units, while the relationship considered between water discharge rate and power generated through these hydro units is nonlinear. Also, there is a water transport delay between hydro units. The presented model is implemented on a sample test system comprising four cascaded hydro units and three thermal units to verify the efficiency of the proposed method. Furthermore, the proposed method is implemented on IEEE 118 bus test case. The results obtained from the simulation show the effectiveness of the presented technique in the case of fuel cost and emission output compared to other approaches recently used. © 2014 Elsevier B.V.


Vieira R.J.,GreenBolt Consulting Ltd | Sharaf A.M.,Sharaf Energy Systems Inc.
Canadian Conference on Electrical and Computer Engineering | Year: 2014

Megawatt scale wind turbines have become the unit of choice in commercial wind farms. Throughout the world wind energy penetration levels continue to rise with many countries having installed wind farm nameplate capacity in excess of ten percent of the national grid. This paper presents an analytical model of a two megawatt permanent magnet synchronous generator directly connected to the wind turbine rotor shaft. Directly connected permanent magnet generators with full scale AC-DC-AC controllers have found favor within the industry because of their lower maintenance and manufacturing costs and ease of grid integration. This paper will present a full analytical model of the wind turbine and the AC-DC-AC controller connected to a stiff utility grid along with their solutions in the time domain. Space vector modulation is utilized for gating the power electronics devices. © 2014 IEEE.


Jolfaei M.G.,Islamic Azad University at Naragh | Sharaf A.M.,Sharaf Energy Systems Inc. | Shariatmadar S.M.,Islamic Azad University at Naragh | Poudeh M.B.,Islamic Azad University at Naein
International Journal of Electrical Power and Energy Systems | Year: 2016

Nonlinear and fast quasi dynamic type loads of different time-varying ranges are introduced to the electric grid systems due to renewable Energy, distributed Generation and Power electronic AC-DC-AC interface converters used in several parts of the power network, the dynamic small signal electromechanical modes are destabilized and dynamic stability limits of AC system is reduced. FACTS - Flexible AC Transmission Devices with conventional coordinated power system Stabilizers are utilized to improve dynamic stability margins and damp unstable and oscillatory electromechanical modes of oscillations. Coordinated Flexible Soft Computing Control Strategies are proposed for damping modes of through supplementary damping torques provided by Static Synchronous Series Compensator - SSSC in addition to classical Power System stabilizers - PSS. To coordinate the dual action of both SSSC and PSS devices a Genetic algorithm Tuning Controller is applied. The dynamic simulation results for optimized controllers are validated using Matlab/Simulink Software Environment. © 2015 Elsevier Ltd. All rights reserved.

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