Abstract：In this paper, a method of three-phase voltage sag forming based on dq transformation is proposed. With the ‘back to back’ linked two PWM voltage-source converters, normal and fault state of infinite grid is simulated. Aiming at seven typical of voltage sag fault (including all the voltage sag types in symmetric, asymmetric excluding zero-sequence and asymmetric containing zero-sequence circumstances), compound operation is completed in synchronous rotational axes dq0 under symmetrical component method applied. Especially, abc-dq0 transformation is amended for asymmetric containing zero-sequence voltage sag situation. So the space vector pulse width modulation (SVPWM) control signal is generated. Three-phase voltage sag generated with this method could satisfy the phase relationship and amplitude relationship of the inter-phase automatically. As a result, point of common connection (PCC) fault voltage could be accurately generated. And the full scope of the depth of voltage dips adjustable and fault duration of any settings are realized. Simulation and part of experiment results show the rationality and validity of the method proposed in this paper.
张波, 颜湘武, 王树岐. 基于dq变换的三相电压暂降生成方法[J]. 电工技术学报, 2011, 26(10): 55-61.
Zhang Bo, Yan Xiangwu, Wang Shuqi. Method of Three-Phase Voltage Sag Forming Based on dq Transformation. Transactions of China Electrotechnical Society, 2011, 26(10): 55-61.
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