Star to Delta Connection for High Power Induction Motor Starting

Use PLC which controls the contactors giving a star delta configuration. Initially the connection should be in star, after 10 seconds of timer setting disconnect the star contactor and give connection for delta and main contactor.

At starting your current will be approximately 6 times your full load current. You may have three contactors such as C1 main contactor, C2 star contactor & C3 delta contactor.C1 is for connecting the supply directly to your motor inputs.

You only have to control C2 and C3. Initially your motor should be in star (ie contactors C1 & C2 are in action) to consume less current ie. your voltage will decrease by (v/root 3) thus your supply starting current will become i/3.But this will remain only for a few seconds. So you have to program in PLC to control C2 by giving timing say 10sec, i think it is enough. After 10 secs your C2 control should be off and your C3 control should be on ie. (c1 & C3 are in action) your motor connection is now in delta ie. supply voltage.

Indeed, it's better to have a soft start system. This is modern power electronic technology to start the motors. The selection of starters depends on many factors like motor rating, voltage rating, application of motor, the running sequence, protection and control. You would require approaching the soft starter manufacturers with all details and they can advise you the best solution.
The star-delta starters is an option but I would prefer to opt for soft start system as it would considerable reduce the current at starting and therefore would allow you to choose upstream equipment with low ratings.

You can also use autotransformers and reactors for this application. If changing to star connection does not provide low enough current you may have to. These types of units add complexity and cost but you offset some cost by determining a duty cycle for operation (number of starts and duration per start over a time interval).