Current reading

[Minhnha]

Hi everyone

 

I'm using clipper Turbo PMAC 2 to control a 3-phase current amplifier. The current amplifier can be found at http://www.justek.com/english/products/detail_jsmd.php. This amplifier need to supply the sinusoidal currents for 3 coils in my experiment. I'm using Torque Control through Analog Signal. However, I have some problems that makes me confuse

1. Does PEWIN support any function to read the actual current through each coils?

2. I used the oscilloscope to measure the coil current but it seems like a square wave instead of sinusoidal. Please help me know how to generate the sine wave current in coil.

3. How to increase the current limitation. I attached the configuration file with this thread. Please help me know which value I need to change in order to increase the current amplititude.

 

Please let me know if any clarification is needed of my issue

 

Thank you so much and I'm looking forward to hearing from you

 

Best regards,

 

Minhnha

linear.zip

[curtwilson]

If I understand you correctly, you are sending an analog torque command to the Justek amplifier, which is executing the brushless motor commutation and current loops.

 

In this mode, the PMAC does not have access to any of the information about the currents in the phases of the motor -- neither the actual magnitude nor the waveshape. All of those matters are completely within the amplifier. The analog output from the PMAC is just a current magnitude command. There is no current feedback to the PMAC in this mode, even just for monitoring.

[Minhnha]

Hi Curtwilson

 

First of all, thank you so much for your help. As you said, I already setup the currents parameters within the amplifier by an interface which is produced by amplifier company. The system then worked well with the commands from PMAC.

 

Thank you so much.

 

Best regards,

 

Minhnha