A novel protection strategy for microgrid based on estimated differential energy of fault currents
Ankan Chandra, Girish Kumar Singh, Vinay Pant
Abstract
The significant benefits of distributed generation (DG) integration in the emerging microgrid are compromised due to substantial challenges associated with the protection. Due to DG penetration, fault current becomes dynamic, leading to make conventional protection methods vulnerable. In order to address this serious issue, a simple and fast protection algorithm, based on Teager-Kaiser Energy Operator (TKEO) is proposed in this paper. This scheme extracts the energy of current signal, retrieved from both ends of the line using TKEO. For fault detection, energy difference of the current signals is used. In order to validate the effectiveness of this proposed scheme, 33 bus test microgrid system operating in both grid-connected and autonomous mode is presented. For evaluating the performance of proposed scheme, high impedance fault cases are also examined. The distinctiveness of the proposed algorithm is that it is principally relying on the energy difference of current signals, therefore it can subdue the difficulties associated with dynamic fault current. Moreover, it does not suffer from computational complexity; thus, inherently hastening the detection process. The test system is designed and simulated in PSCAD-EMTDC software , while MATLAB programming interface is used for developing and testing the proposed algorithm.