基于软件锁相环的电网电压实时检测的研究

针对软件锁相环的特点及应用,提出一种能实时准确获得电网电压的相位和频率信息的软件锁相环(SPLL)的设计方法,该方法从三相电压空间矢量上分离出基波正序负序及谐波分量,采用闭环SPLL控制模型实时跟踪电网正序电压相角,适用在三相电力系统电压平衡、不平衡或电压畸变情况下的电压实时检测。本文引入空间矢量分离与同步坐标变换结合的方法,通过频域线性化建模来设计SPLL控制器结构与参数。最后给出了在Matlab环境下仿真三相电压对称、不对称及畸变且不对称的三种情况下的SPLL跟踪特性曲线,结果表明该模型能有效获取电网电压实时信息。

Research of Real-time Supervision of Grid Voltage

According to the characteristics and application of software phase lock loop （SPLL） , a kind of SPLL＇s designed method is proposed that can accurately obtain the phase and frequency information of the grid voltage, this method of separating the fundamental positive sequence,negative sequence and harmonic components from the threephase voltage space vector,using the closed-loop control model of SPLL which can track the phase angle of positive sequence voltage in real-time, and this method of the real-time voltage detection is suitable for applications under bal- anced, unbalanced or distorted grid. This paper introduced the method of combining space vector separation with syn- chronous coordinate transformation,by the way of designing the linear modeling of structure and parameters of SPLL controller in the frequency domain. Finally, according to using the Matlab to simulate the modeling of balanced grid, unbalance grid and distorted grid,at the same time the tracking characteristic curve of SPLL is obtained,and the result of the model showed that it can effectively obtain the real-time information of grid voltage.