| Because of the high output voltage frequency of medium frequency power supply, there will be more difficulties in controlling the inverter to achieve good output voltage waveform and high capability than the controlling of 50Hz inverter. The inverters are widely used in many important situation, where Fast response and little distorted output voltage is required. It is needed and significative to improve the quality of output voltage. This dissertation focuses on the output voltage control and some important function of single-phase inverters. The followings are the main work:Based on the state-space averaging and linearization technique, the continuous and discrete models of single-phase inverter are established with the load current treated as a disturbance. The influence of dead-time and nonlinear loads on output voltage in single-phase full-bridge inverters is analyzed. A simulation model taking into account dead-time effect and devices loss is established with MATLAB software.To achieve high quality output voltage, diverse voltage waveform control techniques have been developed. Aim at the characteristic of this 400Hz medium frequency inverters, repetitive control strategy is introduced and one repetitive controller is designed for a system. Using MATLAB, the simulation waves are got . With the mathmatics analysis and these waves ,the repetitive control faults that are slowly dynamic response and steady error are explained. One control strategy is present which is base component instantaneous feedback control model paralleling with harmonic component repetitive controller is given to solve these faults. Comparing the output voltage of repetitive controller with instantaneous feedback controller paralleling with repetitive controller, the merits of instantaneous feedback controller paralleling with repetitive controller are pointed out.The validity of the proposed scheme is proved by the experimental results on 2kW single-phase inverters.
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