Use the following steps to test the reference
design with the GUI:
- Connect the USB to UART adapter from the laptop
to J9.
- Connect the AC source(208AC to
400VACL-L) to J1, J2, and J3. J5 and J7 can be connected or can
be left disconnected.
- Connect the DC load to J4 and J8, set to no
load.
- Run the GUI software, choose the correct UART
port and set the baud rate at 115200bps.
- Power on the board, wait for the D25 LED to
blink.
- Wait for relays to close.
- Check the GUI, the DC output voltage is about
530VDC at 380VAC input, since the PFC does not start.
- Send the 0x11 command to start the PFC, until the
DC output voltage is about 680VDC under no load.
- Increase the load step by step, until the DC
output voltage is about 650VDC (when the load is > 500W). Check the AC input
current, DC output voltage, and temperature during loading. Figure 3-4 shows the waveforms under 380VAC, 650VDC, 9kW.
- Unload the board step by step until there is no
load.
- Send the 0x22 command to stop the PFC.
- To bring the system to a safe stop, bring the input AC voltage down to zero.
CAUTION: This reference
design has electrolytic capacitors. The discharge rate of the capacitors is very
slow without an external load. Always pay attention to the DCBUS voltage.A load on the DCBUS can speed up discharge;
otherwise, wait a long time for the DCBUS to get to zero.