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[instaspin] Acim motor does not reach maximum speed

YoungJun Seo
Prodigy 50 points
Other Parts Discussed in Thread: MOTORWARE

We have produced a new drive for us with the hvmtrkit. 
By the way, there is a problem does not reach the maximum speed of the motor. 
It was confirmed to be driven up to speed to lower the current value. 
However, performance is not good. 
Therefore, I am sure that this issue is a matter of parameter setting.
Using the 'spruhj1' document I calculated motor parameters.
but I do not know exactly correct.
Hardware filters also difficult to value accurately calculated.
I have attached a current / voltage acquisition circuit and user.h file.
Please review whether any problems at once.
I lack a lot of experience in motor control.
I think that would be a lot of problems.
Reviewed the document and tell us what went wrong.

I used the motorware project 'lab12b'instaspin.zip

  • 0
    TI__Guru** 118790 points
    1. this isn't your issue, but I would change to these per below:
    #define USER_FORCE_ANGLE_FREQ_Hz (2.0 * USER_ZEROSPEEDLIMIT * USER_IQ_FULL_SCALE_FREQ_Hz)
    //#define MY_MOTOR 103

    2. USER_MOTOR
    did you get these values from ID'ing the motor? They look unusual for such a high voltage hardware (470V/ +/- 120A)

    #define USER_MOTOR_RATED_FLUX (0.9) // I assume your line voltage is quite high, and you are running to 50 or 60 Hz, so this value should be much larger

    other parameters also look strange

    3. the user.h has values for the -MOTION labs. Are you using MOTION? which lab are you running?
    I am surprised to see 12.5 KRPM for max speed on a 4 pole induction machine. It should be no more than 1800 RPM.

    4. I don't understand what you've done with your circuit diagrams, especially current. Have you tried putting your full scale voltage and currents to these circuits and see if you can produce 0V, 1.65V, and 3.3V outputs as expected?
  • 0 in reply to ChrisClearman
    Prodigy 50 points
    Thank you for your interest.
    About your question and answer as follows:

    ;1. this isn't your issue, but I would change to these per below:
    ; #define USER_FORCE_ANGLE_FREQ_Hz (2.0 * USER_ZEROSPEEDLIMIT * USER_IQ_FULL_SCALE_FREQ_Hz)
    ; //#define MY_MOTOR 103

    > Okay, I will try that.

    ; 2. USER_MOTOR
    ; did you get these values from ID'ing the motor? They look unusual for such a high voltage hardware (470V/ +/- 120A)

    > I can`t ID`ing the motor.
    I tried using the GUI COMPOSER an error occurs it could proceed.

    ; #define USER_MOTOR_RATED_FLUX (0.9) // I assume your line voltage is quite high, and you are running to 50 or 60 Hz, so this value
    ;should be much larger
    ;other parameters also look strange

    > Okay I agree with that.
    So. I changed the flux value, but 0.9(motor rated flus) is very good
    0.8165*230.0/400.0 = 0.4694875, this value is correct?

    ; 3. the user.h has values for the -MOTION labs. Are you using MOTION? which lab are you running?
    ; I am surprised to see 12.5 KRPM for max speed on a 4 pole induction machine. It should be no more than 1800 RPM.

    > So I had driven in the field weakening area. So had driven up to the maximum motor speed is not good performance in the acceleration region.
    Motor maximum speed is specified in the data sheet as 12000RPM. (400Hz)

    ; 4. I don't understand what you've done with your circuit diagrams, especially current. Have you tried putting your full scale
    ; voltage and currents to these circuits and see if you can produce 0V, 1.65V, and 3.3V outputs as expected

    > It was confirmed that the correct voltage value.
  • 0 in reply to YoungJun Seo
    TI__Guru** 118790 points
    "0.8165*230.0/400.0 = 0.4694875, this value is correct?"

    Is this motor rated for 400 Hz at 230V or only under field weakening?

    most ACI motors would be rated at 50 or 60 Hz at a given voltage. Use that value.
  • 0 in reply to ChrisClearman
    Prodigy 50 points
    Hi. ChrisClearman.
    I will contact you again.
    Thank you for your previous answer.
    Before you mentioned our motor parameters.
    I want to talk about that again.
    You said our motor parameters were strange.
    I think you are right.
    The motor data sheet states that the base speed is 1500 rpm (50 Hz, 4pole).
    And it was operated well to basic speed using instaspin motion.
    By the way, we want to drive up to 12000rpm (400Hz) using instaspin motion.
    Currently, we are driving to basic speed using instaspin motion, and using scalar (v / f) control method at higher speed.

    Our goal is to drive up to 12000rpm (400Hz) using instaspin motion.
    I wonder if it is possible to do this only by using the filed weakness control method.
    Previously I used the filed weakness method and found that the performance was not good in the acceleration / deceleration region.
    I would like to ask if there is another good way.
    I will wait for your reply.
  • 0 in reply to YoungJun Seo
    TI__Guru** 118790 points

    you would have to use field weakening or powerwarp to achieve the 8x time rated speed you desire. It can only be done by lowering the induced magnetization.  when you lower the field you are going to lose some dynamic torque response capability, so acceleration/decelerations will be more challenging. You will also need to re-tune your current controllers for stability during these operating points.