Synchronverter-Based STATCOM With Voltage Imbalance Compensation Functionality
Lucas do Nascimento Gomes, Armando J. G. Abrantes-Ferreira, Robson F. S. Dias, L.G.B. Rolim
Abstract
In this article, a synchronverter-based D-STATCOM with self-synchronization and voltage imbalance compensation capability with independent operation from the power operating modes is proposed. The S-STATCOM's synchronverter base model is first presented in space-vector representation together with its control strategy with standard D-STATCOM control structure. Then, the voltage imbalance compensation loop is proposed, which uses two well-known resonant control structures, the double second-order generalized integrator and a proportional plus resonant controller, in an innovative way to effectively turn the S-STATCOM into a specialized active filter for negative sequence voltage, compensating the voltage imbalance at the point of common coupling by supplying the corresponding oscillating power locally. Simulation and experimental results on a small scale prototype are presented to validate the control strategy, which successfully reduced voltage imbalances from up to 10% to bellow the 2% acceptable levels.