Model predictive controller for single‐phase distributed generator with seamless transition between grid and off‐grid modes

Abstract

This study develops a model predictive controller for single‐phase distributed generator with seamless transition between the grid and off‐grid modes of operation. In addition, a simple synchronisation mechanism is developed to achieve the smooth transition between the grid and off‐grid modes, thereby avoiding the complex multi‐loop controls. The voltage vectors, hence the switching pulses are generated by using space vector modulation technique based on the minimisation of the cost function of the predictive model. The two cost functions considered are instantaneous power errors and instantaneous voltage errors, respectively, for the grid and islanded operation of the single‐phase generator. The performance of the developed controller for feeding the set‐point powers in grid connected mode and serving the load at nominal voltage and frequency in off‐grid mode is verified using simulations. The simulation results are experimentally validated on a prototype.

Keywords

• seamless transition
• off‐grid mode
• model predictive controller
• single‐phase distributed generator
• complex multiloop controls
• grid connected mode