Design of a controller for operation in transient regime of a single-phase inverter within a microgrid

This paper is presented the modeling and design through simulations of a controller for a single phase inverter for operation in island mode within a microgrid. In particular, a small signal model of a single-phase inverter and controller design for the current loop and voltage loop inverter are presented. For this operation mode is due of fulfilling the goal of maintaining the waveform amplitude and frequency of the voltage signal to be fed to the load, besides guaranteeing a transient response with a reduced number damped oscillations. Therefore, this application is distinguished the design of a new control configuration based on the inclusion of a Posicast control within a proportional integral-proportional (PI-P) control configuration. Being goal of this controller, improve the transient response of the inverter and present a better disturbance rejection. The aim of the Posicast control is to improve the transient response of the energy conversion unit and that of the PI-P control to improve the rejection of disturbances. With this control configuration it is intended to maintain the quality of the voltage signal to be injected into the load. That is, to maintain a total harmonic distortion in the voltage signal to be delivered to the load at a value less than 5%.