Looking at your 6kw inverter

11 hours ago, Sid Genetry Solar said:

Could I ask for photos of the insides of the Solinba inverter?  More curiosity than anything else...what I really want to see is what kind of MOS drive they use.  I find it very bemusing how many Chinese inverter designs are based off of the exact same original design that they've all copied 😉

And, what were the boards you had to replace?  If it's easier, I'd be happy with photos of just the (blown) boards.

What is the FET driving mechanism of the GS inverters? It seems like all the designs I've seen are, as you said, basically the same. How do you do it differently? Is it better or just different?

You got it, talk to your guys next week.

Sure, here ya go.

5 minutes ago, Bossrox said:

Sure, here ya go. 1st time was both upper & lower board, the lower mosfets exploded for no apparent reason, 2nd time I dropped something on the upper board & shorted something, 3rd time was another upper board, just flipped it on 1 day with no load & it never came on, smelled 1 of the upper mosfets burning.

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WOW!

No, just WOW...!!

That's IDENTICAL to a Power Jack v2.2 board.

ZERO innovation in the Chinese LF inverter market...!

See photos on this thread for comparison...

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What I'm picking on is the comically mismatched and uneven FET driving method that PJ uses--and apparently, so do all the other Chinese inverter companies, including Yiyen and Solinba.

Anyone who's worked on engines knows that you want all the cylinders to be matched in specification and performance for a smooth, quiet, reliable engine.  This Chinese drive design has 2 dedicated gate drivers on the high side (TLP350)...and 2 discrete transistor totem pole drivers for the bottom side.  Adding insult to injury (at least on PJ, being the only one I've had on the bench) uses 18v FET drive for the high side, and 12v FET drive for the low side.  So not only do we have hugely different drive voltages (and remember, the big challenge with driving FETs is the gate capacitance)...we also have two completely different types of drivers (with different characteristics) in the same "engine".

If you translated this to a 4-cylinder gas engine, that'd be one rough-running, problem-prone inefficient engine.  And the inverters...well...enough said 😉

10 hours ago, InPhase said:

What is the FET driving mechanism of the GS inverters? It seems like all the designs I've seen are, as you said, basically the same. How do you do it differently? Is it better or just different?

So there's 2 major methods of FET driving: bootstrap, and isolated power supply.  Both have pros and cons. 

• The Chinese way is the isolated power supply, but this requires a custom transformer and a lot more circuitry.  Absolutely nothing wrong with this setup--my complaint is that they use 2 completely different driving methods across the 4 quadrants, and the drive voltages aren't matched.
• GS design is using the bootstrap method...it's a lot more difficult to handle from a software standpoint, but if properly implemented, it can be a very simple solution from a circuitry standpoint.  (FWIW: the bootstrap method is completely useless in any sort of situation that requires 100% throttle.)  The GS inverters use a single driver method for all 4 quarters of the H-bridge...and all 4 quarters run on exactly the same drive voltage.  Perhaps unsurprisingly, the transformers are almost perfectly silent at no load.

I did see in the Solinba inverter reviews on Amazon, that one person compared it to a PJ, noting that the PJ blew out with the ATS function...and the Solinba didn't.  The only difference there is in the software in the processor--as the circuit boards are pretty much literally identical.

Hey, the Chinese are the new Russians ( in more ways than one ). In WW II the Russians wanted us to sell them B-29s. The US refused. So when several had to land on Russian soil, they took photos, disassembled, took measurements, and then copied them. Even down to the " Boeing " on the control wheels ( yokes ). Then the Chinese decided they needed some also. They added turboprops to some of theirs. The Russians called them TU-4s. Some of the Chinese ones carried UAVs, which they reverse engineered from ................................................................................................................................................... the US AQM-34N. I would not be surprised if the Chinese didn't have a copy of our space Shuttles. The Russians did ( Buran ).

So I've been doing some digging around (looking for solutions/info on other inverter-related design challenges), and happened across this webpage: https://manycircuits.blogspot.com/2018/10/must-power-star-felicity-inverter.html

In other words...there is less than zero innovation in the Chinese LF inverter market...!  Apparently all of the following inverter brands use the exact same basic circuit.  While some have repackaged the circuit to a greater or lesser extent (and may have slightly different CPU firmware), the underlying design is basically the same.

• Power Jack
• Solinba
• Yiyen (and I presume direct derivatives such as Aims, Sungold Power, Sigineer)
• Must Inverter
• Felicity Inverter
• Kama Power
• Power Star

Any others??

I look for the signature clues: LF Driver consists of 2 white chips (TLP350) and 4 discrete transistors...a tall switching transformer nearby...rows of resistors connected to an op-amp chip...

I still think it's quite funny.  For some very peculiar reason, they all seem to have the same reliability problems.  Wonder why...

Just because they copied it doesn't mean it is a good design. The Russians/East Germans/ComBloc seemed to be better at picking things that were good and maybe making improvements on them ( Trabant excluded ). In WW II the US shipped ALCo RSD-1 locos to Iran and they were used to move shipments from there to Russia. The Russians liked the design of the locos and the engines in them ( Macintosh & Seymour 539 ). So the ComBloc copied them. That is why the TEM2 locos look and sound so much like the RSD-1. They were still building them in an improved version in 2000 while the ALCo RS1/RSD1 versions stopped production in 1960.

2 hours ago, Sid Genetry Solar said:

So I've been doing some digging around (looking for solutions/info on other inverter-related design challenges), and happened across this webpage: https://manycircuits.blogspot.com/2018/10/must-power-star-felicity-inverter.html

In other words...there is less than zero innovation in the Chinese LF inverter market...!  Apparently all of the following inverter brands use the exact same basic circuit.  While some have repackaged the circuit to a greater or lesser extent (and may have slightly different CPU firmware), the underlying design is basically the same.

• Power Jack
• Solinba
• Yiyen (and I presume direct derivatives such as Aims, Sungold Power, Sigineer)
• Must Inverter
• Felicity Inverter
• Kama Power
• Power Star

Any others??

I look for the signature clues: LF Driver consists of 2 white chips (TLP350) and 4 discrete transistors...a tall switching transformer nearby...rows of resistors connected to an op-amp chip...

I still think it's quite funny.  For some very peculiar reason, they all seem to have the same reliability problems.  Wonder why...

I wouldn't be surprise the other 3k inverts I got that are Pure sign would probley have the same setup, though they are 120v only.  They actually worked better then the PJ 8k I got, which is pretty sad.

And they would put out 3k without complaining, if  you pushed pass that, they would shut down.  I noticed on the PJ that is was more prone to kick on the fans a lot to keep it self cool down even at 1500 watt load.  I've even heard the Coil scream when I really push it.

Just now, The Blind Wolf said:

I wouldn't be surprise the other 3k inverts I got that are Pure sign would probley have the same setup, though they are 120v only.  They actually worked better then the PJ 8k I got, which is pretty sad.

 

And they would put out 3k without complaining, if  you pushed pass that, they would shut down.  I noticed on the PJ that is was more prone to kick on the fans a lot to keep it self cool down even at 1500 watt load.  I've even heard the Coil scream when I really push it.

Yes.  At least most of the other inverter brands listed actually rated the tranny for the desired power output.  PJ doesn't; their trannies are severely underrated.

1 minute ago, Sid Genetry Solar said:

Yes.  At least most of the other inverter brands listed actually rated the tranny for the desired power output.  PJ doesn't; their trannies are severely underrated.

Well, when I seen Sean show off the prototype of the GS Inverter, I was going nuts. I wanted the dang thing, and I still waiting 😛

I remeber calling him up and ordering the conversion to turn the thing into a true split phase, and yet, I've never switch the board, cause well, I'm blind, and I ki nd of was afraid to screw around chaning it out, I might still do it soon once I get the GS inverts out.  I still like the pj inverter, though  I think I might have pushed a wire or something against the tranny when I put it back together and if you try pluging in the ac cord to the charging port it trips the breaker, wasn't doing that before i took it apart.

13 minutes ago, The Blind Wolf said:

Well, when I seen Sean show off the prototype of the GS Inverter, I was going nuts. I wanted the dang thing, and I still waiting 😛

We're still waiting too.  Remains to see what Sean can get out of Backline Freight tomorrow.  Sounds like he's planning to take the day off answering phone calls and drive to the warehouse--if they will allow him/tell him where--and get the load.

2 minutes ago, Sid Genetry Solar said:

We're still waiting too.  Remains to see what Sean can get out of Backline Freight tomorrow.  Sounds like he's planning to take the day off answering phone calls and drive to the warehouse--if they will allow him/tell him where--and get the load.

Is he going to have a way to carry that much weight?  Hope he got a trailer. thats a lot even for a F350.

A Chevy 3500 Dually could handle it without a problem.  I've had over 2000 lbs of Sackrete sitting at the back of the bed and the only thing it did was made the truck ride better. It got the springs off the bump stops.

1800lbs?  I'd put that in the back of a Honda Odyssey.  Say it's twice the weight limit?  Well, I've done it a couple times already...and traversed whole states doing it.  Yeah, the rear springs don't have much play in 'em, but it still gets 25MPG highway...

I actually threatened to drive up to the warehouse and pick them up in an Odyssey 🤣.