Efficiency Increasing of Modular Magnetic Commuted Generators of Wind Power Installations

Abstract

Modular inductor generators, due to their simplicity of design and high reliability,have good prospects for use in aerodynamic power plants of renewable energy, and can become an alternative to synchronous and asynchronous electrical machines that are currently in use. The purpose of the study is to increase the energy conversion efficiency by solving the problems of establishing cause-and-effect relationships and optimal relationships between magnetic flux, EMF, geometry of electrical and magnetic circuits, structural arrangement of electrical windings, and circuit solutions for automatic electromagnetic excitation systems of new type generators. The current issues of exciting magnetic flux effective application for voltage regulation in power supply system’s receiving power from power plants, whichmain generators contain a distributed magnetic system with concentrated electric windings, are considered. The optimal structural compositions and geometry of the relationships between the electrical and magnetic circuits are determined from the basic design equation of the machine, obtained according to the condition of maximum magnetic flux. The reasons for the induction of variable EMF in the DC excitation windings, preventing the effective magnetization of the machine, have been established. The location of electrical windings which makes it possible to weaken or completely compensate for the pulsations of the magnetic flux coupled to the exciting circuitsis proposed. It has been established that in order to eliminate parasitic EMF in the exciting windings, it is necessary to use double-circuit schemes for alternating switching of the magnetic flux in the circuits, with windingsections of the exciting circuits being connected in series. To stabilize the EMF, it is recommended to use an ARV system based on the deviation of the instantaneous value from the reference voltage, using a high-frequency exciting generator.