Design and Implementation of an Over-Current Relay for the Power Electronic-based Converters Protection

摘要

In this paper, a new method used in over-current relay for power electronic-based converters protection is presented. Firstly, the proposed method operation is described and proved the fact that, without using DFT algorithm, this method can quickly detect the fault current to prevent the damage of power electronic components. Further, it is concluded that by applying the proposed method, the harmonics produced by converters don't affect the over-current relay operation. The simulation studies performed in PSCAD/EMTDC software compare the main harmonic amplitude with the other harmonics amplitude. It is deduced that the harmonic orders more than the main harmonic have higher amplitudes. Thus, all harmonics amplitude must be considered in the current calculation. Finally, the suggested relay is made and tested in a laboratory environment.