不对称低电压下的电网电压角度检测

摘要

In order to meet the requirements of low voltage asymmetric ride through for wind turbine and to achieve the asymmetric control of wind turbines, it is necessary to respectively obtain the accurate phase, amplitude and frequency of the positive and negative sequence component of the grid voltage under symmetric and asymmetric conditions. The decoupling formula of the voltage positive and negative sequence component is deduced under the double synchronous reference frame, and the software PLL is used to achieve the amplitude and phase of the positive and negative grid voltage component. It is demonstrated by Matlab simulation that this algorithm has the advantages of accurate detection, anti-interference and strong adaptability.%为满足风电机组低电压不对称穿越的要求，实现风电机组不对称控制，需要在电网对称和不对称跌落情况下分别准确获取电网电压正序和负序分量的相位、幅值和频率。在双dq同步旋转坐标系下理论推导了电压正序和负序分量的解耦公式，运用软件锁相环得出电网电压正序和负序分量的幅值、相位角。最后利用Matlab仿真，验证了该算法具有检测准确、抗干扰和适应性强的优点。