Improvement of power quality of wind-FC energy power hybrid system connected to network

Abstract

Among distributed generation, wind power generation with a variable speed device based on a doubly-fed induction machine used in generating mode (DFIG) is widely utilized with a hybrid energy technology. The control of blade pitch angle is a necessary part of variable speed wind turbines since by controlling the pitch angle, the aerodynamic power that flows through to the generator can be adjusted using the PI controller. In hybrid systems, fuel cell generator may be used as a source. Fuel cells are very attractive to be used with intermittent sources of energy, because of high efficiency, fast load response, modularity and fuel flexibility. This paper introduces hybrid wind (WG)/Fuel Cell (FC) alternative energy system for sustained power generation. The variable speed operation in such wind turbines is achieved by means of a dc-ac multi-level power converter among the rotor winding through fuel cell generator and the stator is directly connected to the grid while battery can meet the load demand above the maximum power available from the FC system for short durations. The aim of this design is minimization of overall cost of generation scheme. Based on simulation results, Dynamic behavior of voltage, power, torque, etc. has been studied. It has been found that these renewable resources would be a feasible solution for distributed generation of electric power for stand-alone applications at remote locations.