Abstract:Electrified railway’s asymmetric operation will produce negative sequence current which is rapid fluctuating, and it will flow into the power system with a serious impact to the power supply equipment’s safe and reliable operation. This paper analyzes the principle of negative sequence currents and the method for suppressing the negative sequence current, and proposes using optimized Steinmetz algorithm to calculate the compensation capacity. Then this paper proposes a thought of three-station collaborative compensation based on Steinmetz optimization algorithm. The compensation capacity is distributed to adjacent station and itself averagely within their rated capacity. This method can significantly reduce the traction substation’s installation capacity of reactive power compensation. This paper also analysis Steinmetz optimize compensation and three station collaborative compensation through matlab simulation. The results show that the collaborative optimization compensation has good effect as the single station compensation.
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