What is the difference between VFD& Soft starter according to load types, Nature, and operating periods?

Soft Starter:

 Soft starter is used to start motors of high rating (for example, 132kW). The voltage to be applied to the motor is linearly raised so that it starts smoothly. Once the rated voltage is applied, the soft starter does not have any role in controlling the speed of the motor.

 

VFD:

  VFD is used for speed control of the motor. The usage of VFD to control the speed of the motor will depend on the process requirements. VFD can be used for starting the motor smoothly and also to control the speed of the motor during running condition.

 

CORRECT ME IF I AM WRONG

Soft starter is a solid-state a device which protects AC electric motors from the large initial inrush of current associated with motor startup. They provide a gentle ramp up to full speed and are used only at startup (and stop, if equipped). Ramping up the initial voltage to the motor produces this gradual start. Soft starters are also known as reduced voltage soft starters (RVSS).

 

VFD is a motor control device that protects and controls the speed of an AC induction motor. A VFD can control the speed of the motor during the start and stop cycle, as well as throughout the run cycle. VFDs are also referred to as adjustable frequency drives (AFDs). VFDs are used in applications where complete speed control is required, energy savings is a goal and custom control is needed.

Both are speed controlling devices. So, S S can control speed by reducing starting current, increasing starting torque . In addition, VFD can't control speed unless it supported by PLC or any other regulator. . Which is the better, VFD or SS if I have 3ph IM 132 KV, 50 hz, 415 V, use to operate a carrier