Research On Distribution Transformer Neutral Current Restrain Methods And Experimental Apparatus

A systematic analysis of the composition and formation mechanism of the neutralcurrent is discussed in this paper. A new neutral current restrain method is proposed.This method adjusts the equivalent impedance of the transformer load, through input acertain volume of power capacitor, and achieves the purpose of reducing the neutralcurrent.In this paper, main research is shown as follows:①After analysis of neutral current restrainer principle, a new neutral currentrestrain method was proposed. And a simulation model was establishment to simulatedifferent load of the transformer. A neutral current restrain experimental platform wasbuilt, based on laboratory micro10kV power distribution system. The feasibility of theneutral current control device was verified by experiments.②Based on the principle of the neutral current restrain, a distribution transformerneutral current restrain device was developed. A variety of electrical parameters can beshowed on the LCD screen, and data could be stored in the system, data could beautomatically sent by GPRS. The system software was developed, which using GPRSwireless transmission technology for data. This software provided a good functionalsupport and facilitated human-computer interaction.③The distribution transformer neutral current restrain device was tested in ZigongCity, Sichuan Province,10kV BanGao line I Shunan segment. The test results showedthat the distribution transformer neutral current restrain device can according to thenature and size of load, dynamic acquisition transformer power parameters, andautomatically adjust the capacitance. The system had a good effect on neutral currentrestrain.Finally, this paper proposes some deficiencies of this system, and gives the relatedcontent of the further research about current restrain.