Tuning the Speed Loop

5263407

Hello,

I’m working with an ACIM, the one shown in section 4.8.1 Getting Parameters From an ACIM Datasheet of the InstaSPIN-FOC User's Guide.

I’ve been going through the labs for instaspin_foc with good success and have gotten to the point in Lab 5b – “Tuning the Speed Loop” where I want to calculate the speed controller gains and I’m a bit lost as to which equations to best use. I pulled the following out of Chapter 11 Tuning Regulators:

And need help understanding if any of the previous parameter information I’ve already extracted and calculated from the motor can be used?

Or am I over complicating this?

Regards,

Rob S

over 5 years ago

0 Han Zhang6 over 5 years ago

TI__Expert 6735 points

Chapter 11 in the user guide gives some commonly used methods to get a starting point of your PI tuning for the control loops. There is no "golden" method to be followed in PI tuning. You can try different tuning method or do trail-and-error tuning.

0 5263407 over 5 years ago in reply to Han Zhang6

Prodigy 60 points

Thank you,

My colleagues and I had read through Chapter 11 previously.

Does TI or do you know if there is an example for a ACIM that goes through the same process as the Anaheim permanent magnet motor described in lab 5b?

Regards,

0 Han Zhang6 over 5 years ago in reply to 5263407

TI__Expert 6735 points

You can convert any lab to ACIM by modify the motor setting in user.h file follow the two motor below in the file as example.

#elif (USER_MOTOR == Marathon_5K33GN2A) // Name must match the motor #define

#define USER_MOTOR_TYPE MOTOR_Type_Induction // Motor_Type_Pm (All Synchronous: BLDC, PMSM, SMPM, IPM) or Motor_Type_Induction (Asynchronous ACI)

#define USER_MOTOR_NUM_POLE_PAIRS (2) // PAIRS, not total poles. Used to calculate user RPM from rotor Hz only

#define USER_MOTOR_Rr (5.508003) // Identified phase to neutral in a Y equivalent circuit (Ohms, float)

#define USER_MOTOR_Rs (10.71121) // Identified phase to neutral in a Y equivalent circuit (Ohms, float)

#define USER_MOTOR_Ls_d (0.05296588) // For Induction, Identified average stator inductance (Henry, float)

#define USER_MOTOR_Ls_q (0.05296588) // For Induction, Identified average stator inductance (Henry, float)

#define USER_MOTOR_RATED_FLUX (0.8165*220.0/60.0) // sqrt(2/3)* Rated V (line-line) / Rated Freq (Hz)

#define USER_MOTOR_MAGNETIZING_CURRENT (1.378) // Identified magnetizing current for induction motors, else NULL

#define USER_MOTOR_RES_EST_CURRENT (0.5) // During Motor ID, maximum current (Amperes, float) used for Rs estimation, 10-20% rated current

#define USER_MOTOR_IND_EST_CURRENT (NULL) // not used for induction

#define USER_MOTOR_MAX_CURRENT (2.0) // CRITICAL: Used during ID and run-time, sets a limit on the maximum current command output of the provided Speed PI Controller to the Iq controller

#define USER_MOTOR_FLUX_EST_FREQ_Hz (5.0) // During Motor ID, maximum commanded speed (Hz, float). Should always use 5 Hz for Induction.

#elif (USER_MOTOR == Kinetek_YDQ1p3_4)

#define USER_MOTOR_TYPE MOTOR_Type_Induction

#define USER_MOTOR_NUM_POLE_PAIRS (2)

#define USER_MOTOR_Rr (0.0)

#define USER_MOTOR_Rs (0.0)

#define USER_MOTOR_Ls_d (0.0)

#define USER_MOTOR_Ls_q (USER_MOTOR_Ls_d)

#define USER_MOTOR_RATED_FLUX (0.8165*16.0/120.0 - USER_MOTOR_Ls_d*USER_MOTOR_MAGNETIZING_CURRENT*2*MATH_PI)

#define USER_MOTOR_MAGNETIZING_CURRENT (0.0)

#define USER_MOTOR_RES_EST_CURRENT (20.0)

#define USER_MOTOR_IND_EST_CURRENT (NULL)

#define USER_MOTOR_MAX_CURRENT (40.0)

#define USER_MOTOR_FLUX_EST_FREQ_Hz (5.0)

FYI, the parameter estimation process for ACIM requires lock rotor. Thanks.

0 5263407 over 5 years ago in reply to Han Zhang6

Prodigy 60 points

Sorry for the delay, had some PTO to used up.

We have made good progress in this area and developed a series of calculations for our motor.

We can close this thread.

Regards,

Rob

C2000™︎ microcontrollers

C2000 microcontrollers forum

Tuning the Speed Loop