A Decentralized Communication-Based Protection Scheme for Meshed Network
The conventional over current protection system of the meshed distribution networks has not been able to
accommodate the changes in the distribution network topology; as a nonselective tripping occurs. Furthermore, high
penetration of inverter-based distributed generation makes changes in the level and direction of the short circuit current during
the fault. This paper introduces a decentralized protection scheme, using a communication system between relays of each
zone, it employs Discrete Wavelet Transform to extract the high frequency components, which exists at fault occurrence, and
the directional characteristic of the superimposed reactive power flows during the fault, calculated by Hilbert Transform. The
proposed protection scheme has been applied to the modified IEEE 14-bus meshed network, integrated with two
inverter-based distributed generators. A realistic modelling of the system has been simulated using PSCAD/EMTDC software.
The proposed protection algorithm has been modeled and tested using MATLAB software.
Index Terms - Decentralized Protection, Discrete Wavelet Transform, Inverter-based Distributed Generation, Superimposed
Reactive Power, Meshed Network.