一种新型的三电平逆变器多目标协调调制策略

A Novel Multi-objective Coordinated Modulation Strategy for Three-level Inverter

提出一种新调制策略,同时考虑平衡中点电压(NPV)、降低开关损耗和降低共模电压(CMV)等多个目标,命名为N3S_CBPWM。对于N3S_CBPWM在每个开关周期内,三相的开关动作分别为0,1和2,确保每个周期三相总的开关次数为3次。在降低CMV的基础上,给出调制波的约束条件。为实现对中点电压的主动控制,给出了N3S_CBPWM的中点电压主动控制方法,比较了NS3_CBPWM和现有调制策略的开关损耗。最后通过实验验证了所提N3S_CBPWM的可行性和优越性。

A new modulation strategy that can simultaneously consider multiple goals such as the neutral point voltage(NPV)balance,switching loss and common mode voltage(CMV)reduction is proposed,named N3S_CBPWM.For N3S_CBPWM,in each switching cycle,there are respectively O,1 and 2 switching actions for the three phases to ensure 3 total switching actions.The constraint conditions of the modulation waves based on CMV reduction are given.NS3_CBPWM and other modulation strategies are compared in switching loss.Finally,the feasibility and superiority of the proposed N3S_CBPWM are verified by experiments.