How many kva need in 30hp motor 3phase?

One horsepower electric is 746 watts, so 30 horsepower is 22.4 KW. You don't specify the power factor or motor efficiency, so I am going to assume a power factor of 0.92 and an efficiency of 0.97, fair values for a 30 horsepower motor. Divide 22.4 KW by 0.92 and then by 0.97 and you get 25.1 KVA. Divide that by three and you get 8.4 KVA per winding. You don't say if the motor is delta or wye connected, so I'm going to assume delta, and multiply by the square root of 3 (1.732) to get 14.5 KVA per phase.