摘要

For three-level active neutral-point-clamped (ANPC) type full-bridge inverters, there are some problems in finite control set mode predictive control (FCS-MPC) method, such as unfixed switching frequency, large harmonics of current, complex multi-objective optimization problems and high requirements on computing efficiency of processor. Firstly, this paper proposed a multi-vector constant switching frequency FCS-MPC method. Model prediction was performed by taking the output voltage of inverter instead of switching vectors as the control set, reducing the amount of model calculations; determining the optimal and sub-optimal voltage vectors through cost function optimization, eliminating multi-objective optimization problems; calculating the vector duration according to cost-function value, and outputs two voltage vectors at the same time to achieve a constant switching frequency and reduce the output current harmonics.Then, the principle of implementing the method in this paper based on different variable constraints is derived. Finally, the redundant vector based on a proportional integral controller is proposed, for balancing the voltage of the DC side capacitor, which has a faster adjustment speed. Simulation and experiment contrast and analyze different FCS-MPC methods, verifying the good performance of the proposed method.