利用 STATCOM 提高风力发电机暂态稳定性

摘要

分析比较了双馈感应风力发电机（ DFIG）与鼠笼感应风力发电机（ SCIG）两种机型，利用Simulink对DFIG ，SCIG在电压骤降时暂态运行特性进行仿真。结果表明SCIG在电压骤降时的影响主要是输入输出功率不匹配造成转子转速的剧增，而DFIG是因变化器耐流耐压不高，容易因低电压造成的转子过电流而损坏，在控制策略失效时crowbar装置把双馈风力发电机变为鼠笼风力发电机运行。 DFIG可通过自身变化器提供无功功率可在一定范围内维持电压稳定，运行较比SCIG稳定。介绍静止无功补偿器（ STATCOM），通过STATCOM来稳定端口电压，仿真表明静止同步器可以明显提高风力发电机组的暂态性能。%The transient responses of the double fed induction generator ( DFIG) and the squirrel cage induction genera-tor ( SCIG) during a voltage sag are simulated by Simulink toolbox.Results show that the voltage sag will cause a rapid increase of the rotor speed for SCIG because of the incompatibility of the input and output power.While for DFIG, the o-ver current in the rotor induced by the voltage sag could damage the variator.In case of a control policy failure, the DFIG will be turned into a SCIG by the crowbar device.However, the DFIG can provide reactive power by the variator to keep a stable voltage within a certain range, so that a more stable operation can be obtained than the SCIG.In the last, the static synchronous compensator ( STATCOM) is introduced to maintain a stable port voltage, which dramatical-ly improves the transient performance of the wind power generator unit.