Wide-Area Frequency based Power Sharing Scheme for Hybrid Multiple Subgrids using Synchrophasor Measurement Units (PMUs)

Modernized existing distribution grids elicited the enhancement of grid resiliency through AC/DC hybrid multiple Subgrids (HMS), which has been a new operational paradigm that assimilates existing AC main grids and authorizes the implementation of state-of-the-art affiliated distributed energy resources (DERs). An ultimatum concerning system operation and control, such as power sharing complexities, voltage stability during contingencies, management and control of power transfer, persuaded the utility framework to improve its operational efficiency, performance and reliability through HMS; formed by AC and DC Subgrids clusters interconnected through a group of interlinking converters (ICs) to balance various load demands, and thereby minimizing the number of conversion stages and furnishing technical feasibility and value-added cost benefits.A wide-area frequency based power sharing (WAFPS) scheme is proposed to manage the power sharing in HMS to reduce complexity in delivering efficient load power during autonomous operation of Subgrids. This method utilizes both AC and DC droop gain values to regulate AC frequency and DC voltage at the point of IC in a decentralized manner. A reliable power sharing method for hybrid system is evaluated at all the operating scenarios such as proportional and disproportional loading and generations.Furthermore, a systematic and illustrative real-time hardware experimental prototype; for an aggregated communication-based system using IEC61131 standard is proposed on Real-Time Digital Simulator (RTDS™) and implemented through MATLAB/Simulink to evaluate the power sharing method at different operating scenarios of AC/DC HMS system. Extensive simulation results are presented for several power flowing conditions to indicate the effectiveness of the proposed power sharing scheme. Subsequently, performance evaluation criteria under steady-state and dynamic conditions are attributed by the establishment of phasor measurement units (PMUs) using IEEE C37.118 standard.A novel bi-directional AC/DC power-flow stratagem with droop control scheme for ICs is ascertained to balance power variation, to regulate voltage and frequency and maintain stability.