Detection Methods of Unbalance Factor and Phase Angle Difference of Positive and Negative Sequence Component of Three-Phase Voltage

For achieving the compensation method which is used for balancing the three-phase unbalanced load by TCR, unbalance factor, phase angle difference of positive and negative sequence component of three-phase voltage should be detected. Accuracy and rapidity of detection is the key factors which affects three-phase unbalance compensation effect. This paper proposes a calculating method of unbalance factor, phase angle difference of positive and negative sequence component of three-phase voltage in the condition of supply voltage unbalance. The method can use dq transformation to achieve the relative parameters by delay sampling voltage to construct PLL signal. Simulation results show that the method can detect the parameters rapidly and accurately.