Analysis of the Electro-Mechanical Performance of Network-Connected Induction Generators Governed by Different AC Voltage Controllers

Abstract

This paper presents a complete analysis of an induction generator linked to the power network through an ac voltage controller aiming to control the generated active and reactive power at different speeds. The ac voltage controller uses three different control strategies, namely; the firing angle-, the extinction angle- and the symmetrical angle- control strategies to control the generator terminal voltage. The generator electrical and mechanical performance characteristics regarding the harmonic distortion factors, active power, reactive power, power factor, steady torque, pulsating torques and efficiency have been computed at different speeds. These characteristics have been determined with the help of novel equivalent circuits in the frequency domain. These equivalent circuits enable accurate calculation of the generator performance characteristics as the numerical techniques are omitted. Also, unlike the dqo and the abc models, the present model takes into account the generator iron losses effects.