UCC28180: Can UCC28180 support output power of 6.6-10KW？

"the efficiency is largely depending on the power stage design", How do you understand this sentence? Does it mean that the higher the power, the lower the efficiency? For example, if I use UCC28070 to design a 22kW PFC, is the efficiency very low?

No, the power stage design means the transformer design and FETs selection.

for 22kW PFC, is it three phase? generally a digital solution is used for such high power, like UCD3138.

If the transformer is very ideal and the FET withstand voltage is sufficient, does it mean that this chip is usable? Can the efficiency also reach over 94%?

Thanks a lot !

What is connected between L102 (487uH) and PGND-PFC?

It is a test point.

What is the connection network SWNode ?

and what are the connections behind L102 (487uH)?

SWNode connects to the switch node of a GaN daughter card

Do you have a schematic diagram of this place?

Someone from GaN team will answer your question

For this sentence: "UCC28180 is a single phase PFC. For two phase condition, you will need two ICs",

I checked the UCC28180 specification sheet and it doesn't mention that it's only a single-phase chip. If I want to use a two-phase line voltage of 380V as AC input, it should be possible, don't you think?

It's connected to the ISO-RET_H network, right?
Also, Q1 and Q2 (STY105NM50N) are used as slow transistors, right? Why choose 600V100A for this slow tube specification, with such a high current?

Where is the current detection on L102 (487uH) ?

U100 is used for current detection. 

STY105NM50N is actually a 500V FET, not 600V. The PFC output is 400V so 500V has enough margin.

what is the ISO-RET_H network you are referring to?

why the current is so high, 100A?

the ISO-RET_H network is the middle of two GaN tube。

U100 only detect the ac current, I wonder how to detect the current of HVbus (also the  current on L102 (487uH)) .

ISO-RET_H is the switching node.

It is a reference design so the FET selection may not be optimized for cost.

Now I don't care about this FET, can you tell me how the current of this inductor(L102 (487uH)) is detected?

We know that PFC inputs generally require rectified DC voltage, bus voltage, and bus current. Why does UCC3138 not require bus current sampling?

HVBus is the PFC output in PMP20873. Like I mentioned before, the inductor current L102 is sensed by U100, which is the bus current you are asking.

If add the GaN daughtercard, the L102 should connect the net ISO-RET_H, and Q1,Q2 LMG3410RWHT act as fast tube in the GaN daughtercard(STY105NM50N in maincard act as slow tube), so the currrent of L102 is not the current of BUS. 

For PFC output current, it is not a must to monitor--------How to understand this sentence? In my impression, all PFC algorithms must include bus output voltage and output current. only a few algorithms, such as single cycle integration, do not require input voltage。

you just need to monitor the output voltage, not the output current.

Why？

Can you tell me the simplest algorithm or framework about PFC?

This is the UCC28180 application schematic. There is no Iout monitor. You just need to monitor the Vout through a resistor divider on Vsense pin.

Is the pin 3(Isense)  output current or input current ?

Only use output voltage,how can we achieve the same phase of input current and input voltage without collecting input voltage and input current? Can you please explain the relevant algorithm principles?

Please read the UCC28180 datasheet (especially section 8.3). 

Please read this handbook to understand PFC principles: https://www.onsemi.com/pub/collateral/hbd853-d.pdf

A YouTube video to show the waveform with UCC28180 EVM: https://www.youtube.com/watch?v=qPx2CWA0WTI

On page 19 in UCC28180 datasheet: it follows that the control loop forces the inductor current to follow the input voltage wave-shape to maintain boost
regulation. 

PFC requires at least input voltage or output current in addition to output voltage, and relying solely on one output voltage is clearly not feasible.

But strangely, UCC28180 does not have an input voltage, is it relying on input current?

VICOMP=k * TSW * (VPK/VOUT) * | sin (wt) |, which varies sinusoidally.

So who got this VICOMP from? Is Isense or other ?
Is VICOMP incorrect as the output of Isense in the attached image? Should the two be separated?