【摘要】 以单相三电平PWM整流器为研究对象,以提高其稳态精度,减少谐波含量,实现有功和无功功率解耦控制为研究目的。首先,以单相三电平PWM整流器数学模型以及瞬时功率理论为出发点,提出一种基于虚拟信号构造和网压幅值计算的瞬时功率求取方法。在此基础上,采用功率前馈解耦控制策略,实现了整流器交流侧电压控制量的解耦,减轻了动态PI控制器的调节负担,提高了整流器动态响应速度。然后,结合一种具有中点电位平衡功能的调制算法,构建了完整的单相三电平PWM整流器直接功率控制系统。最后,通过Matlab/Simulink仿真对比分析验证了该算法的可行性和有效性。更多还原

【Abstract】 The single-phase three-level PWM rectifier was taken as the research object to improve its steady-state accuracy, reduce the harmonic content and realize the decoupling control of active and reactive power. Firstly, based on the mathematical model of single-phase three-level PWM rectifier and instantaneous power theory, a method of instantaneous power calculation based on virtual signal construction and network voltage amplitude calculation was proposed. On this basis, the power feedforward decoupling control strategy was adopted to realize the decoupling of voltage control on the AC side of the rectifier, which reduced the adjustment burden of the dynamic PI controller and improved the dynamic response speed of the rectifier.Then, a complete direct power control system of single-phase three-level PWM rectifier was constructed by combining a modulation algorithm with the function of neutral point potential balance. Finally, the feasibility and effectiveness of the algorithm were verified by Matlab/Simulink simulation.更多还原