Guru
Joined: 13/10/2014
Location: AustraliaPosts: 1860
| Posted: 06:04am 27 May 2023 |
I'm not going to go over again why the chokes stay cool with the cable used, or why I use that cable, one obvious reason and one personal belief reason, So:
1: The chokes are wound with 4G cable.
The current is definitely higher again now, possibly in part due to:
A: The total cable used has been halved since remaking the chokes, less R-Loss.
B:The interplay of lower inductance chokes on each side, however, combined, a higher inductance by an extra 9uH compared to the single 37uH choke used on one side.
Current peaks measured from the base dc offset to the Peak DC current swing is now reaching 568A [26.7kW DC peaks]
Measured a few times to confirm and its always the same. The 1st cycle startup surge is now between 300A and 404A peak, depends on where in the AC cycle that the Compressor takes a dump on the inverter.
Nearly 400ms of huge startup surge before it starts to taper off.
Yellow is Current, Blue AC.
Below: 1st cycle at 404A peak.
The startup AC waveform varies depending where in the cycle it's forced to take the load. VFB in the mix as well?
.
Edited 2023-05-27 16:13 by KeepIS