Control design of parallel-connected PWM DC-AC converters for sustainable energy applications

Abstract

Abstract Parallel-connected PWM DC-AC converters bring lots of merits, such as, additional capacity of power, modularity ability, better thermal regulation, convenient maintenance, and redundancy that have found wide application in sustainable energies. We propose a control technology in which the strengths of rotating sliding manifold (RSM) as well as exponential grey model (EGM) are incorporated to derive a higher performance parallel-connected PWM DC-AC converter. The RSM makes sure that the sliding mode happens from the any starting status, nevertheless the fixed sliding manifold fails to achieve the robustness in the face of parametric variances and perturbations. Once occurring with high non-linear loads, the fluttering existing in the RSM potentially generates a great deal of output-voltage distortion in the parallel-connected PWM DC-AC converters, which deteriorates sustainable energy stability. With the aim of removing the fluttering, the EGM has optimized the RSM control gains to produce both good steady-state and transience behaviour of the PWM DC-AC converter. The potency of the control technology has been well proven in terms of designing procedure, theory analysis, simulation and experimental results.