Multi-time Scale Synchronization and Adaptive Power Sharing Control Scheme for Grid Forming Inverters in a Power Electronics Dominated Grid

Abstract

This paper presents a hierarchical multi-time scale synchronization and adaptive power sharing scheme for fleet of grid-forming (GFM) inverters as backbone of upcoming power electronics dominated grids (PEDG). GFM inverters should be capable of dynamically and seamlessly synchronizing as well as islanding from the network, when demanded. Furthermore, the power sharing coordination between these interconnected GFM inverters needs to be dynamically adjusted, in response to the anticipated system reconfigurations. The seamless integration of GFM inverters and the real-time adjustment of droop gains is vital to address the adverse dynamic interactions observed during such PEDG reconfigurations. This paper proposes a control scheme that enables seamless synchronization of GFM inverters and ensures stability in a PEDG. Moreover, a coordination controller (CC) is proposed to dynamically adjust the droop gains for all interconnected GFM inverters based on their generation capacities; thereby maintaining system resiliency and reliable power sharing against load variations. Simulation results obtained from various case studies emulated in MATLAB Simulink environment indicate the controller's ability to operate efficiently in a dynamically reconfiguring PEDG network.