论文部分内容阅读
在对谐波及无功电流进行补偿的过程中,实时、准确地检测出负荷电流的谐波及无功对于补偿的效果是非常重要的。只有检测出电网中电流和电压的畸变部分,才能采用某种控制方式使主电路产生相应的补偿电流分量,注入到电网中,以达到消除谐波的目的。谐波电流的检测可分为频域和时域两大类[21]。基于频域的电流检测法主要有带通滤波器检测法和快速傅立叶变换法等,但由于它们固有的缺陷,滤波效果较差,不能满足准确、实时性的要求。时域电流检测法在有源滤波器中应用较广。
Harmonic and reactive current in the process of compensation, real-time and accurate detection of load current harmonics and reactive power compensation effect is very important. Only by detecting the distortion of the current and voltage in the power grid, a certain control mode can be used to make the main circuit generate the corresponding compensation current component and inject it into the power grid to achieve the purpose of harmonic elimination. Harmonic current detection can be divided into frequency and time domain two categories [21]. However, due to their inherent defects, the filtering effect is poor and can not meet the requirements of accurate and real-time performance. Time-domain current detection method is widely used in active filters.