Equivalent simulation of doubly-fed induction generators based on controlled source models of converters

Frequent power fluctuations and different operating conditions of a wind farm have adverse influences on power quality and protection relay settings.The electromagnetic transient model of a wind power generator is needed to conduct relevant researches.According to the control principle of MW-DFIGs with PWM converters,an equivalent DFIG modeling method was proposed based on controlled source models of the converters.The converters were simulated as a controlled voltage source in AC side and a controlled current source in DC side.Simulation results of DFIG control signals with step changes and transient response characteristics of asymmetric grid voltages verify the effectiveness of the proposed method.Since the highly frequent turning-on-and-off of switching elements can be ignored in this method,simulation time is much shorter.The simulation efficiency can be increased significantly when the number of simulated DFIGs is more larger.