CRD300DA12E-XM3 Minimum DC Bus Voltage

rachel_

Hello,

I am applying 50Vs to the DC Bus and 120 degree phase shifted pwms to the CRD300DA12E-XM3 inverter. I have been able to scope pwms on the controller side to ensure they are in fact 120 degrees phase shifted. The modulation factor is also non zero.

With these settings I am only seeing 0V on each of the phases. Is there a minimum DC Bus Voltage requirement?

Thanks

Forum_Moderator

Thank you for your post, it has been approved and we will respond as soon as possible.

ChrisN

Hello rachel_,

There is no strict minimum voltage for the system to start switching. However, this system is designed to be operated at 800 V, so we recommend operating it at elevated voltage when looking at the performance of the inverter and SiC modules.

Regarding your issue, assuming you are observing proper gate pulses as you indicated, there are a few things to consider. First, how are you performing the voltage measurement? Are you measuring it with an oscilloscope? If you are measuring directly at the output terminals of the inverter, the waveforms will be square waves. You'll need to ensure you are measuring it appropriately to capture high-frequency square waves. (2) Are you relying on the provided GUI for the voltage measurements? If so, you will need to push the inverter to higher voltages. The voltage feedback circuit on the board is tuned to measure voltages at several hundred volts (where the inverter nominally operated). The circuit has poor measurement resolution at very low voltages.

Thanks,
Chris N.

rachel_

• I am relying on the GUI for voltage measurements. I do now believe this is my issue.

Thank you for your help Chris!