MICROPROCESSOR CONTROL OF WIND-DRIVEN INDUCTION GENERATORS (SPACE HARMONICS, SYMMETRICAL COMPONENTS, FAST FOURIER TRANSFORM)

The use of commercially available three-phase induction motors as induction generators should help to improve the economics of wind turbines. This research proposes a design for a controller for a three-phase wind-driven induction generator using solid state electronics. Two modes of operation are described in this research. In one mode, the generator is operating with resistive heating loads and capacitors for excitation of the generator windings connected at the terminals. In the other mode, the generator is connected by two phases to a single-phase utility service with a balancing load connected to the other generator phase. The electronic design includes the use of a microprocessor and the methods of digital signal processing are used. A fast Fourier Transform algorithm has been written in software for the microprocessor and has been used with the test apparatus to measure the operating parameters of the generator in the modes of operation that are suggested. A software algorithm flowchart for the controller is described, hardware to implement the controller is suggested, and the experimental data that suggested this design is presented. A prototype of the controller has been constructed and is described.