一种改进的三相电网谐波及无功检测方法

为了更加快速、精确地检测出三相电力系统中的谐波和无功电流,基于瞬时无功功率理论,文章在传统d-q检测算法基础上进行了改进,针对锁相环容易受到电网波动影响的缺陷,采用一种无锁相环谐波和无功电流检测方法;针对低通滤波器滤波效果与响应速度无法兼顾的缺陷,采用一种变步长最小均方自适应滤波器;结合以上两种方法的优点,得到一种无锁相环无低通滤波器的检测方法。理论分析和仿真结果验证了该方法的可行性和准确性。

An Improved Three-phase Circuit Harmonics and Reactive Currents Detection Method

In order to improve the detection speed and accuracy of circuit harmonic and reactive current in the three-phase power system, based on the instantaneous reactive power theory, this paper carried out improvement base on traditional d-q detection algorithm, used a detection method for circuit harmonic and reactive current without PLL for the problem of the phase-locked loop; used a variable step-size least mean square (LMS) adaptive filter for the low-pass filter (LPF) problem. Then combining the advantages of these two methods, we received a method without PLL and LPF. Theory analysis and simulation results illustrate feasibility and accuracy of the new method.