一种基于旋转坐标系的新型正负序提取方法

摘要

正负序提取在电能质量检测和电机矢量控制等工程问题中具有重要意义.本文提出基于旋转坐标系的三角函数法(TFM),进行正负序提取.首先,阐述了该方法的理论依据,给出几何解释；然后,提出了带低通滤波的TFM以适应三相交流量中谐波较重或突变较大的情况,同时提出了带锁相环的TFM以适应频率变化或相位测量精度要求较高的场合.最后,通过仿真对比和风力发电并网变流器控制中的应用,说明了本文所述方法既具有较高的稳态精度,也具有较快的动态响应速度.%Calculating positive and negative sequence component is very important for power quality dectection and vector control of the motor. A novel method named as TFM (trigonometric function method) in rotating frame for calculating positive and negative sequence component is proposed in this paper. TFM extracts positive and negative sequence component by trigonometric function based on two instantaneous values in rotating frame. On the basis of the TFM theory and its geometric explanation, a method named as lowpass filter TFM which can be used for three phase ac inputs with harmonics and catastrophe points is designed, and a method named as PLL-TFM (phase-locked loop TFM ) which can be used under the condition of high angle precision and frequency fluctuating is invented. At last, simulation comparisons and its application in control of the converter connected to grid in wind-energy system validate that TFM has the advantage of rapidity and low steady-state error.