Improving the torque direct control method of the asynchronous motor in the converter using the active rectifier

Abstract

The frequency converter study has shown that controlled rectifiers, also known as active rectifiers, have many advantages over uncontrolled rectifiers (diode bridges). The frequency converter with an active rectifier ensures that the input current is sinusoidal, the power factor is 1, the DC voltage constant at the output, the energy exchange according to bidirectional is between the load and grid. The voltage oriented control for the active rectifier will measure the grid voltage and use current control circuits or instantaneous power control circuits. The paper analyses the advantages of using the method of controlling the current in the rectifier circuit when working with the three-phase motor load. The torque direct control method of the motor is enhanced by selecting a new switch table of the voltage vector. The combining power, an active rectifier circuit, inverter, motor, and load create a complete electric drive system with improved working efficiency. The research results were verified by Matlab&Simulink software.