| The linear control approach has been widely used in converters; But PI controller cannot ensure stability under large variations of system condition changes. The system is unable to produce better performances for wide-range load changes and input voltage variation. Recently, with the performance of the converters, modern control theory has been researched widely. the sliding mode control (SMC) has wide application range in the research of converters, complying with the non-linear nature of switch-mode power supplies. Compared with the traditional control modes, the advantages it brings are its high robustness, good dynamic response, simple control implementation and wide-range signal stability.In this paper, sliding mode control scheme of DC/AC converters,DC/DC converters is presented.1. For DC/AC converters, sliding mode control are applied in the single-phase inverter ,analyzing the sliding mode control principle .On the basis of the research, current sliding mode control is presented ,and the simulation result shows that current sliding mode control improves the system performance of dynamic and steady. In order to improve the steady performance of sliding mode control ,a hybrid control structure which improves the dynamic and steady performance incorporating sliding mode control and PI hysteresis control is proposed ,and simulation result proved the strategy is effetely worked.finally, main circuit,driving circuit,conditioning circuit,snubber circuit,protection circuit are designed, and experiment of DC/AC converters is realized based on the TMS320LF2812.2. For DC/DC converters , sliding mode control buck converters is analyzed, including how to choice the parameters,performance optimization and considering the impact of ESR. Then ,buck three level converter is studied, firstly, topology is analyzed; secondly, on the basis of the model using pulse function, sliding mode control is used in the buck three level converters; finally ,sliding mode controller is designed . |
