基于瞬时无功功率理论的谐波检测和抑制的模型参考自适应控制系统

针对瞬时无功功率理论的低通滤波器的选型问题,通过对提取出的基波电流作快速傅里叶变换(FFT)分析,以各次谐波含量和总谐波畸变率(THD)作为Butterworth低通滤波器的阶数和截止频率选择的依据。首先,建立了谐波源公共连接点(PCC)处基于瞬时无功功率理论的谐波检测的仿真模型;其次,根据提取的基波电流的畸变程度,详细说明了低通滤波器的选型方法;最后,将模型参考自适应理论引入开环谐波检测系统,克服了实际模型中内部参数改变和外部扰动对谐波检测的影响。理论分析和仿真实验表明,该系统具有良好的谐波检测精度和对基波提取具有较强的鲁棒性和自适应性。

Model Reference adaptive control system of harmonic detection and suppression based on instantaneous reactive power theory

In view of the low-pass filter selection problem based on instantaneous reactive power theory,fundamental wave current is extracted through Fast Fourier Transform analysis,and the every harmonic content and total harmonic distortion are selected as the basis of Butterworth low-pass filter order and cut off frequency.Firstly,the simulation model of harmonic detection is established based on the instantaneous reactive power theory in common connection point of harmonic source;Secondly,according to distortion degree of the extraction of fundamental wave current,low-pass filter selection method is described in detail,Finally,the open-loop harmonic detection system is introduced based on the theory of model reference self-adaptive theory,which overcomes the internal parameter change and external disturbance in practical model for the influence of harmonic detection.Theoretical analysis and simulation experiments show that the system has good harmonics detection precision and has better robust and self-adaptive for the fundamental wave extraction.