Operation of induction generator based wind emulator and integration with microgrid

Abstract

Development of wind turbine systems are growing rapidly, and larger installations are built to harness more wind energy and to produce electricity. Therefore, advanced power electronics are developed and introduced for power conversion systems of the wind turbines and for the integration with the electrical power grid. A Wind Energy Generation System has been set up in the Laboratory for Clean Energy Research. A 11kW induction machine operates as a prime mover to convert wind energy into mechanical power. The prime mover is coupled together with a 7.5kW induction machine. The 7.5kW induction machine generates and supply power into a Windy Boy Protection Box that rectifies Alternating Current (AC) voltage into Direct Current (DC) voltage. The DC voltage is subsequently delivered into the Windy Boy Inverters that converts rectified current into AC current and supply into the microgrid testbed. Control of the Wind Energy Generation System is designed in LabVIEW software. Two control modes, manual and wind simulation mode are designed to study the characteristics of the generator and the power conversion system. As an induction machine functions as a generator, frequency and voltage levels are different from the microgrid. The technical differences between grid-connected and isolated operations with distributed generators are by means of the control of frequency and voltage. This report discusses about the wind emulator operational process, experimental results from varying rotor speeds to power generated and the process of isolated and grid-connected operation.