基于变频器受控源模拟的双馈风机等效仿真

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

风电场功率波动频繁且运行方式多变,对电网电能质量及继电保护整定产生不利影响。若进行相关研究,需建立风电机组的电磁暂态模型。以兆瓦级双馈风电机组为研究对象,在分析双馈风机控制原理的基础上,提出一种基于变频器受控源模拟的双馈风机等效建模方法,风机控制系统中的变频器交流侧采用受控电压源,直流侧采用受控电流源模拟。风机控制输入信号设定值阶跃变化及电网电压不对称暂态特性响应的仿真结果,均验证了该方法的有效性。由于无需计及开关元件的快速频繁通断,仿真时间大为缩短,且模拟风机台数越多,仿真效率越高。

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.