A study on reducing inrush current in Kenjeran 150 KV substation power transformer by installing VCT-ICL

摘要

Reduction of inrush current at power transformers can be done by using the VCT-ICL which is a modification of the DC-type reactor inrush current limiter with the addition of VCT components which contribute to reducing distortion in the voltage waveform. Through ATP-EMTP program, the simulation is performed by obtaining three modeling conditions, namely the existing modeling system (before being installed VCT-ICL), modeling once ICL (DC reactor) installed, and modeling once VCT-ICL installed. From the modeling results, the comparison inrush currents and voltages of the three conditions of modeling can be evaluated. The value of the impedance at VCT-ICL proportional to the value of inrush current is reduced, so the method is flexible enough to reduce inrush currents such as ICL (DC reactor). However, the simulation results prove that the distortion in the voltage waveform occur in conditions after the ICL (DC reactor) has been installed. Then after VCT mounted on ICL with DC reactor parameter values are the same, the distortion generated due to the installation of DC reactor can be reduced.