Comparision of VSI and CSI fed to Induction motor

DIFFERENCES BETWEEN VSI AND CSI

To understand in easy way the below table provides the differences between VSI and CSI

VSI	CSI
VSI is used to fed impressed voltages	CSI is used to fed the impressed currents
Load commutation is not possible	Both forced and load commutations are possible
Open loop and closed loop operations are possible	Only closed loop control is possible
Voltage with variable frequency is fed to Induction motor	The current with variable frequency is fed to Induction motor
The efficiency is medium	The efficiency is high
These drives are suitable for low, medium power applications	These drives are suitable for medium and high power applications
Multimotor operation is possible	Multimotor operation is not possible
Pulse Width Modulation( PWM) technique is used to reduce the problems of harmonic content, torque pulsations, motor heating etc.	The PWM technique is not used in CSI so the distortions in the output are more.
It gives good and satisfactory behavior in transient and dynamic state.	Poor dynamic behaviour