Investigation and Development of Converter-Inverter set for Wind Power Generation

Abstract

Wind energy conversion system (WECS) model development for steady and dynamic state analysis and design has been research issue in recent years. This investigative research work presents a new block-based approach for WECS dynamic modelling. The blocks (modules) developed by Aalborg University - Denmark, RISO national laboratory based on Kaimal Spectra have been customized, updated and integrated into Matlab/Simulink platform and then utilized to simulate performance of 5kW WECS based on Permanent Magnet Synchronous Generator (PMSG). In addition to the developed block sets, in this research work, a proportional-integral controller is designed to control the turbine pitch and integrated with the simulation models. The simulation results demonstrate that the model outputs are in agreement with what is expected. Moreover, in this research work, alternative closed-loop control strategy of generator and load side converters are presented for which an investigation and simulation of two-level, back-to-back voltage source converter has been carried out using PLECS software on Matlab/Simulink. Both rotor speed of the PMSG side and the DC-link voltage of load side are controlled by a PI controller. This control strategy has been achieved by using field oriented control (FOC) often referred as vector control method. Using PLECS software packages for modeling and simulation of circuit-oriented electric and electronic dynamic systems, is considered as special feature for high-speed simulations in graphic modeling (block diagram) method that is commonly used in control engineering. The validity and performance of the applied control scheme has been verified by simulation results and the simulation results demonstrate that the controller is capable of maintaining constant DC-link voltage under varying supply voltage (250V - 400 V) and frequency (25Hz -50Hz) from the source and different electrical load conditions (DC and AC).