Control system with sinusoidal PWM three-phase inverter with a frequency scalar control of induction motor

The principles of implementation of the control system with sinusoidal PWM inverter voltage frequency scalar and vector control induction motor are reviewed. Comparisons of simple control system with sinusoidal PWM control system and sinusoidal PWM control with an additional third-harmonic signal and gain modulated control signal are carried out. There are shown the maximum amplitude and actual values phase and line inverter output voltage at the maximum amplitude of the control signals. Recommendations on the choice of supply voltage induction motor electric drive with frequency scalar control are presented.

I. Introduction

Generally modern variable frequency induction motor drive contains a two-level (tier) frequency converter with controlled or uncontrolled converter, which work with constant, small angles control and invert [1], [2]. Rectifier loaded on a standalone voltage inverter operating in a pulse width modulation (PWM). This structure of frequency converter allows providing high power factor of power circuit for the drive independently of drive mode and the implementation of laws frequency vector control to achieve the best performance of dynamic and static control. Thus, of particular interest for study is the principles of the implementation of sinusoidal PWM three-phase inverter with frequency induction motor control, allowing to provide work induction motor for given values of maximum speed of the electric drive and maximum torque of static load.