一种简单实用的基波检测方法

基波信号检测是有源滤波器的关键技术之一。提出一种采用并联谐振检测电网中基波信号的方法，该检测电路由一个LC电路构成的选频网络构成。理论分析表明：该选频网络对基波电流的阻抗远大于谐波阻抗，当被检测电流信号流经时，输出电压基本不含谐波。以一组电路参数为例研究了该选频网络的幅值响应、相位响应和动态响应，并分析了这种检测方式的优缺点。实验证明该检测方法具有优良的滤波效果和较快的动态响应。

A SIMPLE APPROACH TO FUNDAMENTAL CURRENT DETECTION

The timely detecting approach to the fundamental current signal is one of the key techniques for the active power filter. A novel fundamental detecting method for the power system in terms of LC parallel resonance is proposed in this paper. The detecting circuit is composed of the LC component and it has been found that its fundamental impedance is much greater than the harmonic impedance. When the detected current signal passes the filtering network, the output voltage amplitude contains few harmonic voltages. The amplitude and phase curve as well as the transient response of the detecting circuit are investigated in terms of a group of parameters by using MATLAB. The validity of the theory is proved by the excellent experimental results and fairly rapid transient response.