单电源型五电平逆变器调控策略的研究

RESEARCH ON REGULATION STRATEGY OF SINGLE-SUPPLY FIVE-LEVEL INVERTER

基于悬浮电容供电的单电源型逆变器仅需单个独立电源,在特定场合具有更好的适用性,但传统调制策略无法对拓扑结构中的悬浮电容电压进行控制,严重影响逆变器输出性能。为解决上述问题,提出一种基于工作模式切换的新型调控策略,对2种工作模式的调制原理和稳压控制的原理及特性进行详细理论分析与计算。所提调控策略可通过选择不同的工作模式,实现对悬浮电容不同的充放电效果,进而实现对悬浮电容电压的快速、稳定调节。最后,通过仿真与实验验证所提新型调控策略的正确性与可行性。

Single-supply inverter based on floating capacitor power supply only needs a single independent voltage source,which has better applicability in specific occasions. However,the floating capacitor voltage in the topology cannot be controlled with traditional modulation strategy,which seriously affects the output performance of the inverter. In order to solve the above problem,a new regulation strategy based on working mode switching was proposed. The detailed theoretical analysis and calculation of modulation principle of two working modes,principle of voltage regulation control and regulator control characteristics were carried out. The proposed regulation strategy can achieve different charging and discharging effects on the floating capacitor by selecting different working modes. Therefore,fast and stable regulation of the floating capacitor voltage can be achieved. Finally,the correctness and feasibility of the proposed new regulation strategy were verified by simulation and experiment.