An experimental investigation of self-excitation in capacitor excited induction generators

摘要

Self-excitation process in induction generators is a complex physical phenomenon, that has been studied extensively in the past. In-depth coverage of methods of steady-state analysis and models for simulation of transients is provided in the existing literature. Reports regarding experimental investigation of dynamics are however much less detailed. Usually, their only purpose is to prove the theoretical concepts. This paper attempts to fill in this gap by providing a prey experimental treatment of the self-excitation process in induction generators. The emphasis is placed on situations that lead to voltage collapse and total demagnetization of the machine, and on variable speed operation of the induction generator with a fixed capacitor bank. Operation with capacitors connected in star and delta under no-load conditions, connection of the purely resistive load, and connection of the resistive load with short-shunt compensation are elaborated. It is shown that some of the commonly quoted features of a self-excited generator operation do not necessarily hold true, while others are conferred.