Current regulated PWM-CSI induction motor drive system without a speed sensor

A current source inverter (CSI)-induction motor drive system without a speed sensor is considered. An input DC link current which is kept constant by a pulse-width-modulated converter with sinusoidal input current is supplied in the PWM inverter. The inverter output current with sinusoidal wave is directly regulated by employing the modulation index control of the PWM strategy. Experiments show that high-performance steady-state behavior and acceleration/deceleration characteristics with smooth drives and low noise of the motor have been obtained. It is demonstrated that the system with only the current sensor has the same steady-state and transient characteristics as the system with the voltage and the current sensors.<>