Fuel Cell Distributed Generation System Research Articles

Performance Recovery of Voltage Source Converters With Application to Grid-Connected Fuel Cell DGs

Most common types of distributed generation systems utilize power electronic interfaces and, in particular, three-phase voltage source converters (VSCs) which are mainly used to regulate active and reactive power delivered to the grid. The main drawbacks of VSCs originate from their nonlinearities, control strategies, and lack of robustness against uncertainties. In this paper, two time-scale separation redesign technique is proposed to improve the overall robustness of VSCs and address the issues of uncertainties. The proposed controller is applied to a grid-connected solid oxide fuel cell distributed generation system to recover the trajectories of the nominal system despite the presence of uncertainties. Abrupt changes in the input dc voltage, grid-side voltage, line impedance and PWM malfunctions are just a few uncertainties considered in our evaluations. Simulation results based on detailed model indicate that the redesigned system with lower filter gain $(\boldsymbol {\epsilon })$ achieves more reliable performance in compare to the conventional current control scheme. The results also verified that the redesigned controller is quite successful in improving the startup and tracking responses along with enhancing the overall robustness of the system.

Utilization of fuel cell energy source for distribution power generation: theory, modeling and review of research work

The energy crisis is one of the most critical phenomena happening in today's world. The depletion of fossil fuels, the rise in oil prices, and the increase in power demand are the main causes of this problem. Concern over environmental conditions and human health make renewable energy one of the most viable alternative solutions to this crisis. Among various types of renewable energy, fuel cell technology shows a great potential in the electrical energy sector for several reasons, such as high efficiency, clean operation, and immunity to the adverse effects of weather conditions. Recent works prove that fuel cell technology is expected to be a better choice for distributed generation purposes. Distributed generation, which is installed near load centers, can moderate the stress of high electricity demand in the mainstream utility grid. This paper presents an overview of fuel cell technology, with emphasis on fuel cell types, characteristics, and applications. The differences among the various fuel cell types and the dynamic models of each type required for simulation are also discussed. Focus is given to the application of fuel cells in a distributed generation system, the requirements of a fuel cell-based generating system, and issues in distributed generation integration. The present study also discusses the power conditioning unit, which is an important component in the fuel cell-based generating system, as well as its control strategy. Discussion is likewise made on the use of suitable energy storage units for the fuel cell distributed generation system, with regard to battery types and storage control. By adding energy storage units to the fuel cell system, the capabilities of the existing generation system can improve system stability performance. Streszczenie. W artykule zaprezentowano przegląd technologii wytwarzania energii z wykorzystaniem ogniw paliwowych koncentrując sie na analizie roznych typow i ich zastosowan. Szczegolną uwage zwrocono na zastosowanie ogniw paliwowych w rozproszonych systemach wytwarzania energii. Analizowano tez uklad kondycjonowania energii oraz jego sterowanie. Wykorzystanie ogniw paliwowych w rozproszonych systemach wytwarzania energii elektrycznej - teoria, modelowanie i przegląd prac badawczych

Sliding Mode Control of the Battery Bank for the Fuel Cell-based Distributed Generation System

The dynamic models for the fuel cell power and the configuration of the fuel cell distributed generation system are shown in this paper. Due to nonlinear characteristics of fuel cell model, the output voltage of fuel cell varies greatly when the load changes. A novel interface is designed to provide a constant output voltage for charging of the battery bank of the fuel cell distributed generation. The thesis presents a sliding mode control design of PEMFC distributed generation system. A cascaded control structure is chosen for ease of control realization and to exploit the motion separation property of power converters. The simulation results confirm the output current and voltage of the PEM fuel cell array converge rapidly to their reference values.

Active, Reactive and Harmonic compensation control of grid interfaced fuel cell system

Abstract This paper presents the modelling and control of grid interfaced fuel cell distributed generation system with embedded active filter function. The features of active power filter have been incorporated in the control circuit of the current controlled-voltage source inverter interfacing the fuel cell to the grid. Thus the same inverter is utilised to inject power generated from fuel cell source to the grid and to act as shunt active power filter to compensate for load current harmonics, load reactive power demand and load current imbalance. Thus, after compensation, the grid current is sinusoidal and in-phase with grid voltage. Simulation in MATAB and experimentation using DSP is carried out to verify the operation and the control principle. The results are obtained for different operating conditions with varying load demands to prove the effectiveness of the entire system.

Power Flow Control of Grid-Connected Fuel Cell Distributed Generation Systems

This paper presents the operation of Fuel Cell Distributed Generation(FCDG) systems in distribution systems. Hence, modeling, controller design, and simulation study of a Solid Oxide Fuel Cell(SOFC) distributed generation(DG) system are investigated. The physical model of the fuel cell stack and dynamic models of power conditioning units are described. Then, suitable control architecture based on fuzzy logic and the neural network for the overall system is presented in order to activate power control and power quality improvement. A MATLAB/Simulink simulation model is developed for the SOFC DG system by combining the individual component models and the controllers designed for the power conditioning units. Simulation results are given to show the overall system performance including active power control and voltage regulation capability of the distribution system.

Control of PEM fuel cell distributed generation systems

This paper presents modeling, controller design, and simulation study of a proton exchange membrane fuel cell (PEMFC) distributed generation (DG) system. The overall configuration of the PEMFC DG system is given, dynamic models for the PEMFC power plant and its power electronic interfacing are briefly described, and controller design methodologies for the power conditioning units to control the power flow from the fuel cell power plant to the utility grid are presented. A MATLAB/Simulink simulation model is developed for the PEMFC DG system by combining the individual component models and the controllers designed for the power conditioning units. Simulation results are given to show the overall system performance including load-following and fault-handling capability of the system.