Popis: |
Compared with the two-level APF, the three-level neutral point clamped (ANPC) has more output levels, less harmonic influence, and lower equipment loss in the process of harmonic compensation. However, due to the conservatism of single-step prediction, it can only provide the reliability at k+1 time, and it does not provide the relevant information for the next time optimal. Moreover, the control of threelevel APF needs to consider multiple targets at the same time, which will cause certain tracking error. In this paper, a multi-step prediction method is proposed. The optimal and suboptimal switching states at k+1 are obtained by cycling. The optimal switching states in two control cycles can be obtained by substituting the optimal switching states at k+2. The method improves the reliability of the control process, and the simulation results show that the harmonic content of the power grid is low, which meets the relevant requirements. |