Sensorless control of wound rotor induction generator (WRIG) for wind power applications: The experimental test platform

The present paper presents the experimental platform used during the tests of state observers and sensorless control of a variable speed wound rotor induction generator system. The main application of this system is wind power and it was developed and improved in the latest years as interest in power generation especially using wind as primary energy, has increased tremendously. It is basically composed by: WRIG, two power electronics converters connected in the rotor side of WRIG: machine-side inverter (MSC) and grid-side inverter (GSC), a line filter, and the data acquisition and control system (dSpace DS 1103). Both converters are commercial units and are vector controlled using appropriate interfaces. They are back-to-back connected, sharing the same DC bus, one supplied through a line filter from the power grid, and the other one with the output on the rotor of the generator. The stator of the generator is directly connected to the power grid. All components are extensively described in the paper and their functions are discussed. The control structures for both inverters and the Matlab-Simulink® software used for implementing them using the control and acquisition system DS1103 and its interface are presented. Some basic measurements are illustrated and discussed.