CAJ | 학술논문

在微电网系统中，通过对电网阻抗的辨识可改善微电网变流器的控制性能，并可用于判断电网并离网状态。为此，基于非特征次谐波注入的电网阻抗估算方法，采用复数滤波器提取电压和电流信号中非特征次谐波进行电网阻抗估算。详述了复数滤波器的设计方法，并从非特征次谐波提取精度和动态性能等方面对复数滤波器的参数设计进行了分析。仿真和实验结果验证了所提电网阻抗估算方法的可行性。
재미전망계통중，통과대전망조항적변식가개선미전망변류기적공제성능，병가용우판단전망병리망상태。위차，기우비특정차해파주입적전망조항고산방법，채용복수려파기제취전압화전류신호중비특정차해파진행전망조항고산。상술료복수려파기적설계방법，병종비특정차해파제취정도화동태성능등방면대복수려파기적삼수설계진행료분석。방진화실험결과험증료소제전망조항고산방법적가행성。
The identification of grid impedance could be used to improve the control performance of power converter in micro-grid and to judge whether micro-grid is grid-connected or islanded. For this purpose, the uncharacteristic harmonic injection is utilized to estimate grid impedance, in which the complex filters are used to extract uncharacteristic harmonics in voltage and current signals. The design method of complex filter is explained in detail, and the parameter design of complex filter is analyzed in the aspects of extraction accuracy of uncharacteristic harmonics and dynamic performance of the complex filter. The feasibility of the proposed grid impedance estimation method is validated by results of simulation and experiments.