基于重采样和反馈理论的三相系统谐波检测方法

提出了基于重采样和反馈理论的数字化谐波检测方法。根据反馈理论设计了一个三相数字谐波检测系统，从而确保在瞬时有功和无功电流的直流分量频谱不混叠的情况下能够对瞬时有功和无功电流分别进行4倍重采样。仿真试验表明：该方法缩短了数字低通滤波器的动态时间，减少了计算量；该数字系统可精确地提取电网谐波电流，既保证了数字滤波器的准确性，又克服了长期以来数字滤波器跟随性和实时性差的问题，具有较高的实用价值。

Detection of Harmonics in Three-Phase System Based on Resampling and Feedback Theory

A digitized harmonic detection method based on resampling and feedback theory is proposed. According to feedback theory, a three-phase digitized harmonic detection is designed, thus it is ensured that the quadruple resampling of instantaneous active and reactive currents can be respectively proceeded under the condition that the spectrum of DC component of active current does not alias with the spectrum of AC component of reactive current. Simulation results show that the proposed method can shortens the dynamic time of digitized low-pass filter and reduce the calculation burden. The designed system can extract harmonic currents in power system accurately; besides, not only not only the accuracy of digitized filter can be ensured, but also the bad following characteristic and real-time performance of digital filters, which exist for a long time, can be overcome.