Analysis of an Active Superconducting Current Controller Considering the Protective Coordination and Voltage Compensation in Power Systems

In this paper, an active superconducting current controller is used for fault current limiting, protective coordination, and voltage compensating in a typical power system. In the grid-connected micro-grid, the performance of a conventional fault current limiter can disrupt the protective coordination of the micro-grid overcurrent relays as well as the relays between the main grid and micro-grid. The control strategy is designed for implementing normal limiting impedance in the upstream fault mode and a zero limiting impedance in the downstream fault mode so that the protective coordination between all relays is maintained. Also, to investigate the effect of the controller on voltage compensating, by obtaining the line transmission matrix, the controller setting parameters for compensating the voltage at any point of the line are obtained. In this case, the controller is adjusted such that the magnitude of the receiving end and the sending end voltages of the line become equal. Simulation results using MATLAB software confirm the proper performance of the proposed active controller for the above-mentioned purposes.