优化电压偏差的换流站站用变压器分接开关控制方法

换流站站用变压器的分接开关挡位控制对电压调节起到关键作用。介绍了某±500 kV换流站站用变压器有载调压分接开关控制器的运行异常概况,分析了现有控制方法在级电压偏差和最优挡位控制方面的不足,找出了不能将电压偏差缩减至最小的原因。提出了一种以满足实际误差与调挡需求的偏移量为启动判据,以低压侧线电压的最小误差平方值为目标,寻找最优挡位的控制方法。最后,结合换流站中压配电母线电压的运行状况,从适应电压波动能力和控制计算复杂度两方面评价了该方法的控制效果。

Control Method of Station Transformer Tap-changer for Converter Station Based on Optimizing Voltage Deviation

Tap-changer control of station transformer in converter station plays a key role in voltage regulation.This paper introduces the general situation of abnormal operation of the station transformer on-load tap-changer controller in a±500 kV converter station,analyses the shortcomings of the existing control method in voltage deviation and optimum tap control,and finds out the reason why the voltage deviation cannot be reduced to the minimum.Then this paper proposes a control method which takes the offset of actual error and the demand of gear adjustment as the starting criterion,takes the minimum error square value of the line voltage at low voltage side as the objective,and searches for optimum tap position.Finally,based on the operation of medium voltage distribution bus voltage in converter station,the control effect of this method is evaluated from two aspects:the ability to adapt to voltage fluctuation and the complexity of control calculation.