Technical Lecture Session
Unbalance Load, SOGI, Synchronous Reference Frame, Decentralized Control, Droop Control, Parallel Inverter, Distributed Generation, Microgrid
A synchronous reference frame (SRF) based decentralized control architecture for parallel operation of inverters is proposed in this paper. The proposed control technique enables decentralized inverters to share the unbalanced load. Simultaneously any undesirable voltage unbalances at the inverter output terminal are compensated conforming to IEEE std 141-1993. Active (P) and reactive (Q) power droops are provided based on the positive sequence component (PSC) of the SRF currents, and a virtual resistance is emulated simultaneously at the inverter output to improve load sharing between the parallel-connected inverters. The proposed decentralized control technique functions based on inverter terminal data eliminating any requirement inter-communication networks. The control structure is simple and free from any computational complexities and associated delays as it is designed to operate in the SRF. The negative sequence component (NSC) of the output voltage is compensated using a closed-loop resonant controller. The feasibility of the proposed approach is validated through comprehensive experimental results on a laboratory test prototype.