APF谐波电流检测中积分法的仿真研究

Simulation Research of Integration Method for Harmonic Current Detection in APF

介绍了基于瞬时无功功率理论的ip-iq谐波检测法,对该方法中使用的低通滤波器的进行了分析,结果表明低通滤波器会给系统带了来延时,影响了检测精度。提出了一种利用简单的积分、延时和增益环节替代传统低通滤波器的新方法,大大缩短了检测过程中的延时。同时,在三相不对称系统中,仅需对负载电流进行简单的三角函数变换,就可以灵活地应用该方法,取代了原有的三相构造法,且检测结果可以同时得到基波电流的有功、无功分量。在Matlab/Simulink环境中建立仿真模型,用低通滤波器和提出的积分法分别在三相对称和不对称系统中进行仿真实验,通过比较分析表明了该方法的有效性。

The main factors were analyzed, which caused errors to harmonic detection of APF, based on instantaneous reactive power theory. The results show that the delay caused by the low-pass filter has a great influence on the detection accuracy. The integration method can reduce the latency in the detection process using simple integrator, delay and gain links instead of the conventional low-pass filter, though further study of it. On this basis, an improved method was proposed, only after simple trigonometric transformation, the integration method can be flexibly applied in single-phase system, and the results of detection can obtain active fundamental current and reactive component simultaneously. The new method for detection of harmonic has improved the detection accuracy in a certain extent. Simulation models of the three-phase symmetric and single-phase systems in the Matlab / Simulink environment were created, to compare and analyze the different simulation results of a low-pass filter and the integration respectively. An experiment proves the good trace of changes in current detection.