Medium voltage drives and synchronous transfer control

[@sasanzeraati6248]

Thanks a lot for the great video.

[@sohailjanjua123]

Hi, I like your video. Thanks

[@lukeslingher6043]

Very informative.

[@hi-io6ry]

Hello, I have a question regarding VFD to mains synchronization. 1. Is mains reference signal taken from the VFD power supply? 2. The output waveform of VFD is PWM square with full DC voltage. Even if you van synchronize the voltage phase of the mains and the VFD output, how can you connect them together, without short circuiting?

[@eatoncorp]

Thank you for reaching out. Please visit shorturl.at/pKMY4 for more information on VFD power supply.

[@AltKuyperian]

kW is actually 75% of HP, I would not consider those even "roughly" the same, and that's at unity PF. The amount of HP delivered to a load would be even worse, seeing as how many motors draw decent VARs.

[@volodumurkalunyak4651]

You mixed up kW and kVA. For motor running with VFD, appproximate motor effiency * motor power factor (both at full load) should be close to 1HP/1kW. If result is > 1HP/1kW, users get some safety factor (like using buses rated at 400A with at most 350A).

[@AltKuyperian]

@@volodumurkalunyak4651 Perhaps power factor may not play into HP calculations but the actual conversion of kW to HP is 0.746, so 75% like I said.

[@volodumurkalunyak4651]

@@AltKuyperian power factor isnt incleded in the output HP number, but it is included in input Amps. All input conductors must be rated for sufficient current (power factor plays a role there).