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The classical model predictive control(MPC) is frequency conversion control, which will lead to larger ripples of the output variables. To solve this problem, this paper proposes a fixed frequency model predictive current control strategy based on space vector modulation(SVM). This strategy combines the switching sequence distribution method of continuous SVM to divide the voltage vector to reconstruct the control set. The constructed control set consists of four voltage vectors, including two effective voltage vectors and two zero voltage vectors. In order to reduce the current ripple through the smallest current error in each sampling period, the cost function is improved. Finally, simulation and experiment verify the feasibility and effectiveness of the scheme.

Dual buck inverter (DBI) is an effective solution to deal with inherent drawbacks of bridge topology. However, DBI does not has the capability to handle common mode (CM) interference and efficient bidirectional power flow. This paper presents a modified bidirectional dual buck DC-AC converter, in contrast with traditional topology which can provide a high efficiency and suppress the common mode current in the meantime. According to structural improvement, operation modes of the converter has been optimized. In addition, the model predictive control (MPC) has been adopted to approach bidirectional conversion and switching control. Finally, simulation and experimental results demonstrate the feasibility of the implemented converter and the restraint of CM current.

Dual buck half bridge inverter(DBHBI) has a benefit of no shoot-through issue, however, severe waveform distortion is badly undesirable. Hysteresis control is commonly used to improve output quality, which has fast dynamic response and easy to approach. Since the switching frequency in the hysteresis control is unfixed, voltage loss and harmonic frequency issues are inevitable. The paper proposes a novel hybrid sine pulse width modulation control strategy. When the inductor current is greater than the critical inductor current, DBHBI is switched to the half-cycle SPWM mode, otherwise, to the full-cycle SPWM mode. Besides, nonlinear relationship between input and output is optimized to linear relationship which facilitates the controller. In addition, the influences of the mode transition are discussed, and control methods to solve distortion problems under different traditions are proposed. Finally, simulation and experiment results demonstrate the superior performance of implemented strategy on waveform improvement.