Syed Zulqadar Hassan

Energy management and control of grid-connected wind/fuel cell/battery Hybrid Renewable Energy System

This manuscript explains an energy management and control of grid-connected Hybrid Renewable Energy System (HRES). It describes a Wind Turbine (WT) and hybrid energy storage system based on hydrogen technology (fuel cell), and battery. DC/DC converters are used to connect all the energy sources and storage system to a common DC bus. The output of DC bus is integrated to the national grid through three phase inverter to increase the continuity of power. The proposed HRES is working under classical-based supervisory control algorithm. According to the proposed algorithm, the wind is used the primary energy source to satisfy the load demands. The fuel cell is used to ensure long-term energy balance by using the hydrogen technology. The battery is utilized as a backup and high energy density device to keep the DC-bus voltage constant. The performance of the HRES is verified under real-world record of wind speed and load variations for the twenty five households at Islamabad, Pakistan. Matlab/Simulink results are provided to show the right performance of the proposed system in terms of load tracking, voltage regulation, and grid stability.

Stand-alone/grid-tied wind power system with battery/supercapacitor hybrid energy storage

Standalone/grid-tied wind energy generating system under intermittent wind velocity and changing load condition is a challenging task. The objective of this paper is to develop a Hybrid Power System (HPS) integrating a renewable energy source, namely, a Wind Turbine (WT) coupled with Permanent Magnet Synchronous Generator (PMSG) and a hybrid energy storage system, i.e., a battery bank and super-capacitor in the proposed architecture. The proposed system is connected to the national grid to increase reliability and continuity of power. In the proposed system, the WT is taken as primary energy source to satisfy the domestic load demand. The battery is added to regulate the output power of WT under unpredictable power fluctuations. The super-capacitor overfills the slow response of battery under rapidly changing load condition due to its high power density. The power management and regulation is performed by Coordinated Energy Management System (CEMS). The performance of the presented design is tested under different wind speed and load conditions for the Matlab simulation of 48 Hrs. The proposed system demonstrates excellent performance in terms of grid stability, voltage and frequency regulation.

Fuzzy embedded MPPT modeling and control of PV system in a hybrid power system

The literature is populated with different Maximum Power Point Tracking (MPPT) methods for Photovoltaic (PV) system to obtain maximum power from it. This piece of work provides an artificial intelligence-based fuzzy logic MPPT modeling and control of PV system in a grid connected hybrid power system under different weather patterns. The proposed technique uses seven fuzzy sets with seven linguistic variables applied to a DC-DC converter. Furthermore, a battery module is added as an energy storage system during surplus power and/or backup device during load demand. The overall operation of system is performed by classical logic power management switching algorithm. The performance of proposed method is compared with and without Proportional Integral Derivative (PID) MPPT controllers. MATLAB simulation results show better behavior of proposed method in terms of load tracking and reliability.

Design and power control of fuel cell/electrolyzer/microturbine/ultra-capacitor hybrid power plant

This paper provides a design and power control of hybrid grid power plant including a fuel cell, an electrolyzer, a microturbine and an ultra-capacitor which supplies power to support the grid and grid integrated typical domestic load. The proposed hybrid power plant is working under simple power control algorithm. According to the proposed algorithm, the fuel cell is the primary power source. The microturbine is added as a secondary system to confirm continuous power flow. The ultra-capacitor module is utilized as a backup and complement device to take care of the load following problems of fuel cell during transient. The electrolyzer is used as a dump load to generate hydrogen and to reduce power fluctuation during surplus power. A complete Matlab/Simulink model has been established to check the performance of the proposed system for the real load conditions. Simulation results show that the proposed system facilitates the grid stability, power quality and continuity.

Integration and control of an off-grid hybrid wind/PV generation system for rural applications

This study focuses on a stand-alone hybrid system combining photovoltaic/wind with super-capacitor/battery storage for rural residential applications. Various DC/DC converters are used to control the power flow to the load and Maximum Power Point Tracker (MPPT) is used for maximum power extraction from the photovoltaic/wind systems. In the proposed architecture, the Photovoltaic (PV) has the priority to meet the required load. A wind turbine system is integrated in the system to support PV during demand. Both super-capacitor and battery are used as an energy storage system during surplus power and/or backup device during demand. The proposed system operates in such a way to maintain the State of Charge (SoC) of battery above 80%, which consequently improves the battery life and its performance. The proposed system uses real time solar, wind data and a load of five rural households available at the University of Nottingham, Malaysia campus. MATLAB simulation results conclude that the proposed system can compensate power fluctuation and meet the required load without any grid connections.

Fuel Cell/Electrolyzer/Ultra-capacitor hybrid power system: Focus on integration, power control and grid synchronization

Solid Oxide Fuel Cell (SOFC) is considered a promising green power source and offers various benefits such as modularity, high efficiency and cogeneration options. Unfortunately, the slow dynamics and gas starvation problems are the demerits of SOFC. Due to which the SOFC fails in providing fast response and also face load following problems. However, an integration of SOFC with complementary device such as an Ultra-capacitor (UC) can solve these problems. This paper presents an integration and power control of hybrid power system combining a SOFC stack, an Electrolyzer (ELZ) and an energy storage system in the form of hydrogen tanks and an UC module. A dynamic power flow controller is designed which supervised and managed all the energy sources and power converters to maximize the use of SOFC/ELZ/UC and reduce burden on the grid. According to the strategy, the SOFC is the used as the prior energy source. The UC is utilized as a complement and/or backup device to cover the slow dynamics of the SOFC during transient, while the ELZ is used as a dump load to generate hydrogen for SOFC during surplus power. The proposed system is synchronized to the grid through power electronic converters to enhance the reliability and continuity of power. The performance of the proposed system is investigated under real-world record of load conditions. Matlab/Simulink results are presented to verify the effectiveness of the proposed system interms of load tracking, power transfer, voltage regulation and grid synchronization.

Performance of grid-integrated Wind/Microturbine/battery Hybrid renewable power system

This paper describes the performance of grid-integrated Hybrid Renewable Power System (HRPS). It establishes a Wind Turbine (WT), a Microturbine (MT) and a battery which support the dump load, Local Grid (LG) and/or grid integrated domestic load. DC/DC converters are used to join WT, MT and battery in a common DC bus. The output of DC bus is synchronized to the local grid through hysteresis controlled three-phase voltage source converter to increase the continuity of power. The proposed HRPS is working under switching control algorithm. According to the proposed algorithm, the wind energy is controlled via optimal torque based maximum power point tracking method, and is used the primary energy source to meet the load demands. The MT is added as a secondary system to confirm continuous power flow. The battery is utilized as a high energy density and/or back device to keep the DC-bus voltage constant. The dump load is used to consume any excess power inside the system. To verify the effectiveness and performance of proposed system, a test bed is created using Matlab/Simulink based on recorded wind speed and load profile of a small community at Peshawar, Pakistan region. Various results are obtained to show proposed power system performance in terms of grid synchronization, voltage and frequency stability, power quality and load tracking.

Integration and simulation of wind with hydrogen/supercapacitor storage hybrid system

This piece of work focuses on wind power generation with hybrid storage system, e.g., hydrogen (fuel cell) and supercapacitor. The wind power has the priority to meet the demand. The fuel cell is added as a backup to ensure long-term energy balance while the supercapacitor is utilized as a buffer and/or backup source during transient. The complete architecture is connected to the utility through various power converters to improve the overall system stability, continuity and reliability of power. The operation of the proposed system is performed through Power Management and Control Strategy (PMCS). The PMCS works in such a way as to maximize the use of wind/fuel/supercapacitor and reduce stress on the utility. The performance of the system is tested for complete one day under different weather and load conditions. MATLAB/Simulink results are shown to verify the effectiveness of the proposed model.

Design and control of photovoltaic/wind/battery based microgrid system

This paper deals with the design and control of a micro-grid, including various alternative energy resources (photovoltaic and wind) and battery energy storage system which operates in stand-alone as well as in grid-connected mode. The proposed micro-grid is controlled via various non-isolated converters while an energy management is performed through switching based algorithm. According to the strategy, the wind is used as the primary power source while the Photovoltaic (PV) is added to improve the reliability of system under different weather conditions. The battery module is utilized as an energy storage system during surplus power and/or backup device during demand. The proposed system used real record of weather pattern and load conditions for a small community at Islamabad, Pakistan. This city is gifted with several natural resources that can generate a significant amount of power energy for the region. MATLAB simulation results show the effectiveness of proposed system in terms of grid stability, power sharing, load tracking and power quality.

Design and control of wind/super-capacitor/battery/diesel engine power plant

This piece of work provides a hybrid power plant integrating a wind coupled with Permanent Magnet Synchronous Generator (PMSG), a super-capacitor (SC), a battery and a diesel engine (DE) set which operates without a grid connection. Each subsystem (e.g., wind, SC, battery, DE) has controlled through non-isolated PID/PI embedded controller power converters while the overall operation and power flow priorities are achieved through Programming Logic Controller (PLC). According to the algorithm, the wind has the priority to meet the demand. The SC and battery modules are utilized as an energy storage devices during surplus power and/or backup during demand. A diesel engine is also added to increase the reliability of the system for 24 hours. The performance of proposed design is tested at different wind speed and load conditions for a small community at Karachi, Pakistan. MATLAB results conclude the effectiveness of proposed system in terms of power quality and load tracking.