Resonant PID Controller Design for a Three-Phase Four-Wire Voltage Inverter with Split DC Buses

The problem of improving the synchronization accuracy of three-phase voltages of an autonomous four-wire inverter with the network is considered. Increasing the synchronization accuracy is achieved by applying a proportional-integral-differential (PID) resonant controller. A new structure of the PID resonant controller and a methodology for calculating its parameters are proposed. The peculiarity of the proposed approach consists in the application of the time-scale separation method, which makes it possible to calculate the PID component of the controller regardless of the choice of the parameters of its resonant components. Application of this approach to the calculation of the controller of autonomous voltage inverters makes it possible to improve electromagnetic compatibility and reduce losses in distributed power generation systems. The results of numerical simulation are presented.