An adaptive three-phase UPS inverter controller

Linear and nonlinear adaptive control strategies for a three-phase uninterruptible power supply (UPS) inverters are described. Without a priori knowledge of the UPS system parameters, the adaptive controller synthesizes an internal input/output digital controller mapping which minimizes the instantaneous load voltage waveform errors relative to the sinusoidal load voltage command. An on-line adaptive learning algorithm is described which promotes steady-state controller stability. Results of computer simulations and experiments using this adaptive control technique are presented