改进型谐波与基波有功和无功电流检测法

在三相电压不对称时，传统ip-iq检测法中的锁相环检测到的电压相位并非该电压的正序分量相位，因此得到的瞬时有功和无功电流会存在误差．有鉴于此，文中提出了一种改进的ip-iq检测法，该方法用基于低通滤波器的基波正序电压提取单元代替传统的电压检测电路，提取单元能检测出电压正序分量的相位，从而在三相不对称时仍能精确检测基波有功、无功电流．最后通过仿真分析对所提出方法的正确性和可行性进行了证明．

Improved Detecting Method for Harmonic and Fundamental Active and Reactive Currents

In the case of unsymmetrical three-phase voltage, the phase-lock loop in the traditional i_p-i_q detecting method cannot be used to detect the phase of the positive sequence voltage. As a result, there exist errors in the transient active and reactive currents. To solve this problem, an improved i_p-i_q detecting method is put forward. In this method, a fundamental positive sequence voltage unit based on the low-pass filter, which can detect the phase of the positive sequence voltage, is adopted to replace the traditional voltage detecting circuit. Thus, the fundamental active and reactive currents in the case of unsymmetrical three-phase voltage can be detected. The correctness and feasibility of the proposed method are finally verified by a simulation analysis.