Neural network based adaptive state feedback controller for inverter with voltage matching circuit

This paper describes a discrete adaptive state feedback controller used to load current control in terms of variable DC voltage of inverter. Controller was designed by using linear quadratic optimization method. Adaptive LQR was used because of non-stationarity of the control system caused by Voltage Matching Circuit - VMC. Gain values of the adaptive controller were approximated by using an artificial neural network. The VMC was realized as an additional buck converter integrated with the main inverter. As the load of the 2-level inverter a 3-phase symmetric RL circuit was used. Simulation tests show the behavior of the load current regulation during DC bus voltage level step changes. The dependence between current RMS value and inverter DC bus voltage level was also shown. Simulation test was made by using Matlab Simulink and PLECS software.