Sliding mode controller with GM(1,1) model controlled parallel-connected DC-AC converters

In this paper, the design of parallel-connected dc-ac converters using sliding mode controller with GM(1,1) model is presented. AC output voltage regulation and balanced current-sharing among the parallel modules is achieved by means of sliding mode control (SMC). But, the chattering around the sliding surface exists when the system uncertainties values are overestimated. This may excite the unmodelled high-frequency dynamics of the system and imperil system. In order to overcome the chattering, GM(1,1) model is used to estimate the system uncertainties boundaries. A low distorted sinusoidal output voltage can be obtained even though at the nonlinear load conditions because SMC with GM(1,1) model provides the excellent performances, such as fast dynamics response, robustness to system uncertainties, and reduced chattering. Simulation results are performed to verify this proposed control scheme.