INVERTER COMMON MODE VOLTAGE INJECTION CONTROL METHOD AND APPARATUS

A common-mode voltage injection control method and apparatus for an inverter are provided. For the method and apparatus, a common-mode voltage for a DPWM mode is calculated based on three-phase port voltages and an output power command (S202); a common-mode voltage for an MPC modulation mode is calculated based on the direct current bus voltage, the three-phase port voltages, and the output power command (S204); a modulation proportion is determined based on a maximum phase voltage peak value of the three-phase port voltages, the direct current bus voltage, and a power factor of the output power command (S206); and a common-mode injection voltage is generated based on the common-mode voltage for the DPWM mode, the modulation proportion, and the common-mode voltage for the MPC modulation mode (S208). In this way, the common-mode voltages for the modulation modes and the modulation proportion for generating the common-mode injection voltage are adjusted according to the real-time state of the inverter, which is conducive to achieving the flexibility of the inverter under different operating conditions, and helps meet the requirements of both a relatively small ripple current of a direct current bus capacitor and a relatively small switching loss.