Fast voltage detection method for the voltage ride through operation of grid-tied renewable energy generation systems

As the scale of renewable energy resources connected to the grid is increasing remarkably, the strict gird codes are formulated in order to ensure the grid safety. Among the grid codes, the low voltage ride through (LVRT) regulation is important because it defines the acquired response to support the grid stability. This paper proposed a new voltage detection method, which consists of the traditional three-phase phase lock loop and a new low voltage detection procedure for the low voltage ride through operation of grid-tied renewable energy generation systems. This method can detect the amplitude of voltage sag within 5ms by tracking either the maximum point or the zero point. Finally, validity and accuracy of the proposed method is verified by simulation and experimental results.