Parameter sensitivity factor-based grid-connected inverter phase-locked loop parameter identification method

The invention provides a grid-connected inverter phase-locked loop parameter identification method based on parameter sensitivity factors, and belongs to the field of electric energy quality and control. The phase-locked loop parameters comprise a phase-locked loop proportionality coefficient and a phase-locked loop integral coefficient. According to the method, a positive sequence impedance model containing unknown phase-locked loop parameters is established, a frequency band where parameter sensitivity factors meet requirements is obtained by using the parameter sensitivity factors, and parameter estimation is performed by using a particle swarm optimization algorithm in combination with impedance measured in the frequency band where the parameter sensitivity factors meet the requirements. Multiple groups of phase-locked loop parameter estimation values are obtained, smooth frequency bands of the phase-locked loop parameter estimation values are determined, and a parameter identification result is obtained.