D Current Scaling Not 1:1

[derekcook]

Hello, 

I am applying D current to my motor while running in speed mode to artificially load down my system to validate system functionality at high current. If I set the D current reference - tempStatorRefCurrentDQ.d to 150A, I get 50A of current on my A, B and C phases. What causes this scale factor? Why is the D current reference not instead adding 150A of current on my A, B and C phases? 

[linestream-adam]

Derek,

When you modify the D axis reference, you are adding magnetic flux into the motor. This will change the response of the motor to Q axis current. Without monitoring both values, it is difficult to determine what the current value should be. Is the 50A you are measuring the peak value or rms value?

[derekcook]

Adam, what would be the formula to determine how much current injecting D current (flux) should add to my system?

[derekcook]

Hey Adam, 

I am aware I am adding magnetic flux to the motor. I just was wanting to know if there is any way to determine the amount of current injecting the magnetic flux will add to my system? I am monitoring RMS ABC current. 

[derekcook]

Hey Adam, 

Is there a way to determine the amount of current injecting magnetic flux will add to my system? What is this equation?