Suction Blower What Is The Best Possible Solution For A High Inertia Load[blower]? S/d Or Dol?

What is the best possible solution for a high inertia load[blower]? s/d or dol? - suction blower

I want a 50hp motor for high inertia loads start [fan].
If I start with the star-delta motor encountered in the Delta.
I set the timer so. But it is always hopping.
In the delta of the load 400A

If I is with the Department of Labor is now 400A and achieve normal 41A (power) take up to 28 seconds. In this area, the engine overheated.

I try this test with the closing of the ventilator [blank]
How do I solve this problem?

In what could solve the problem? Star Delta or DOL