The reliability and stability of a grid-connected converter is vital to the power conversion system. The faults of switching device and current sensor lead to operation failure for a grid-connected converter. An improved model predictive power control (MPPC) based on reconstructed currents is proposed for fault-tolerant operation of a grid-connected converter. Firstly, the three-phase currents are reconstructed using the sampled dc current and normal sensor information according to the relationship between the voltage vector and output currents. Secondly, the predictive power model is built based on fault-tolerant three-phase four-switch topology. Then the reconstructed current is used for the MPPC method. To keep the balance of dc capacitor voltages, the cost function is optimised and the switching vector, which minimises the cost function, is applied to the fault-tolerant converter. Finally, the experiment platform and simulation models are built to verify the proposed method. The results show that the proposed MPPC using reconstructed currents can keep the fault-tolerant operation of the grid-connected converter with sinusoidal currents and stable output power. The proposed method achieves the fault-tolerant operation under switching device and ac current sensor fault, which improve the reliability of the system.

中文翻译：

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使用重构电流的容错并网转换器的模型预测功率控制

并网转换器的可靠性和稳定性对于功率转换系统至关重要。开关设备和电流传感器的故障会导致并网转换器的运行失败。提出了一种基于重构电流的改进模型预测功率控制（MPPC），用于并网转换器的容错操作。首先，根据电压矢量和输出电流之间的关系，使用采样的直流电流和正常传感器信息重建三相电流。其次，基于容错三相四开关拓扑建立了预测功率模型。然后，将重构电流用于MPPC方法。为了保持直流电容器电压的平衡，优化了成本函数，并通过了使向量函数最小的开关矢量，应用于容错转换器。最后，建立了实验平台和仿真模型以验证该方法。结果表明，所提出的利用重构电流的MPPC能够以正弦电流和稳定的输出功率保持并网转换器的容错运行。该方法实现了开关设备和交流电流传感器故障下的容错操作，提高了系统的可靠性。