Power flow control and islanding detection of the local generation system with induction generator

In this paper a local generation system (LGS) based on an induction generator (IG) is presented. The IG supplies the active power to the system with the support of a voltage source converter (VSC) for power conditioning. With the LGS connected to the grid through coupling inductors the deficit or the excess of power production of the IG is imported or exported to the grid at unity power factor. In autonomous operation of the LGS a buck converter, bi-directional boost converter and battery set are connected at the DC terminals of the VSC to control the DC bus voltage and supplying power to the local load at constant voltage frequency and amplitude. The LGS includes an active islanding detection method, battery charge function and a procedure to reconnect the LGS with the grid after the voltage is reestablished.