How can i modify torque/flux Kp and Ki value to let the value of Iq and Ip to be stable

[SkyWork]

Due to i want to produce the max torque value, so i set Iq reference to be nominal current value and Id to be zero, but after checking the value by

MC_GetIqdMotor1() ==> to get the current Iq and Id value

MC_GetIqdrefMotor1() ==> to get the reference Iq and Id value

I find the value is very instable and oscillates huge against to the reference as the figure

Is there any way to let the value to be stable? because i try many Kp/Ki value but the result is not good enough.

Thanks