谐波和无功改进检测方法在注入式有源滤波器中的研究

Compounded Method for Detecting Currents with Harmonics and Reactive Power in the Injection Active Power Filter

注入式有源滤波器对谐波抑制的效果不但取决于其拓扑结构和工作原理,还取决于电网中无功、谐波电流的检测方法。针对注入式有源滤波器的延时现象,提出了改进方法,即用简单积分加延时增益环节来取代传统的ip-iq方法。所提方法可将检测延时降到1/6个电源周期,节约成本,还可扩展到单相、三相用电及其他不平衡工况。将改进参考坐标法也引用到注入式有源滤波中,可以省去锁相环及三角计算。上述方法的应用,大大提高了谐波和无功检测效果,具有较好的应用价值。

Whether the hybrid active power filter with injection circuit（ IHAPF） get desirable effect of harmonic suppression depends on the detecting method mainly. This paper focused on delay and convenience on the performance of injection APF and proposed an improved method with simple integration and delay and gain to substitute the low pass filter of conventional ip-iqmethod,which can reduce the detecting delay to 1/6 of source period and cost. Meanwhile,this method can also be applied to a single-phase circuit and three-phase four-wire circuit and the unbalanced three-phase load. On the other hand,an improved synchronous-reference-frame method for detecting currents with reactive power and harmonics was proposed. By synchronizing the positive sequence vector of the grid voltage,this improved synchronous reference frame method is very simple to implement without the phase locked loop and complex calculations for sinusoidal functions. The simulation and experiment results verify the perfect filtering performance of the shunt HAPF with the novel detecting method.