EEVblog 1620 - Deye Solar Hybrid Inverter EXTREME TEARDOWN

[EEVblog]

Extreme teardown of the Deye SUN-5K-SG04LP1 5kW hybrid solar inverter.
Will it contain the quality components claimed?
Also a topology reverse engineering of all the stages.

00:00 - A generous and coincidental donation from a viewer
00:37 - We have the brochure, let's check the claims!
02:44 - Front panel PCB
03:46 - The gigantic heatsink
04:44 - Nippon Chemi-Con Capacitors? REALLY?
05:54 - Heatsunk and potted inductors and transformer teardown
10:19 - Main PCB's and the confusing layout
12:53 - The fused battery input
13:37 - Are the MOSFET's and IGBT's as advertised?
15:10 - SMD high current links for PnP benefits
16:14 - Detailed circuit topology schematic reverse engineering
18:29 - Earth connection testing
19:07 - MOSFET vs IGBT
19:51 - Grid side IGBT switching and tri-level switching
20:46 - Solar Panels are capacitors to earth and that screws the CMRR
21:34 - HERIC switching topology and patent lawsuits!
23:50 - Grid and Load connections
25:07 - The battery bidirectional DC-DC converter
28:14 - H-Bridge and parallelism
30:14 - Switching drive stages
31:25 - Main processor PCB and a TI DSP ripoff?
32:51 - Redundant backup DSP controller?
34:40 - Genrator and Load conection relay switching
35:49 - Panasonic Relays? WHERE?
37:02 - User Connection PCB
38:25 - Conclusion



Datasheets:
https://www.fet.discoveree.io/datasheet.php?view=pdf&file=crmicro/crsq027n10n.pdf
https://www.magnachip.com/wp-content/uploads/2020/10/MBQ40T65QES-1.pdf
https://www.lcsc.com/datasheet/lcsc_datasheet_2209081730_Wuxi-NCE-Power-Semiconductor-NCE40TS120VTP_C5160411.pdf
https://wmsc.lcsc.com/wmsc/upload/file/pdf/v2/lcsc/2211151030_Vishay-Intertech-VS-EPX3007L-N3_C5263741.pdf
ADVchip DSP: https://file.elecfans.com/web2/M00/6F/21/poYBAGNEwS-AKpNeAIfcFmyDrAQ938.pdf
AVP32F335 DSP: http://advancechip.com/mobile/32fd/61.html
Fraunhofer ISE Successful in Patent Infringement Process for HERIC Inverter Technology:
https://www.ise.fraunhofer.de/en/press-media/press-releases/2022/fraunhofer-ise-successful-in-patent-infringement-process-for-inverter-technology.html

[Kleinstein]

The supply crisis during Covid may could be a reason for changing the suppliers.  They may have also updated there documentations too.

[Phoenix]

Looks good!

DRM = Demand Response Modes. It's an Australian thing that never really took off. It was to allow your smart meter or other utility device to control things like your aircon, hot water, solar, battery etc. It can read a weird switch matrix with resistance levels, hence the odd looking circuit to monitor it.

[BMK]

I have the 8kW version of this.

-Main MCU/DSP is TI (TMS320) Also another small MCU beside it. 2 separate JTAGS, assuming one for each.
-Power relays all Panasonic.
-Cannot see main AC or DC caps, but I don't see Chemicon aywhere.
-Display MCU is Gigadevice ARM thingy.

@Dave. I have a falulty LCD on mine. Would you sell it?

[Coyote]

Great review, I do appreciate also the block diagram of the user @Phoenix. It would be nice to have a source code of the Firmware or some reverse engineering around it, since it has many flaws. It would be nice to see also the high voltage model teardown and inverters with two batteries. When two batteries are connected, then inverter stops charging when one of the batteries reaches charge SOC setpoint, even if the other is half empty. But there is even worse: if you have multiple inverters and multiple batteries, inverters will stop charging batteries if one battery of the entire bank becomes charged.

The inverter itself isn't such bad quality, but the FW is a pain. DEYE could do a favor to itself by leaking the FW source code and then collect all, when users would make a stable version of it. 

[agtrbt]

China has a trend to domesticate all production chain in the state for geopolitical crap.

[floobydust]

Hey is that Litz wire aluminium? Looking a bit dodgy. Copper-coated for better flavour 

[parasole]

Hey is that Litz wire aluminium? Looking a bit dodgy. Copper-coated for better flavour 

Considering skin effect, it should work as expected, a bigger problem at high power might be thermal dissipation as aluminium thermal conductivity is about half if comparing with copper…   

[Kleinstein]

For a higher frequency transformer it makes little to no sense to use Al wire. The wire material costs are only a small fraction. The question with the litz wire in the transformer may be if the normal litz wire for better flexibility or special RF litz with isolared wires to reduce the skin effect / current concentration. Not sure if the RF litz already makes sense at a still relatively moderate frequency.

For the inductors it is a bit strange to have them all in one heat sink with only thin isolator in between and not separate chambers in the cast, which would allow for better heat transfer. The potting compound should be the more conductive version, but it is still a relatively poor thermal conductor.

[ballsystemlord]

Thanks @Phoenix for helping Dave with this one.

[ballsystemlord]

@Dave ,
You really went all out with this teardown compared to, say

( which could have used a bit more going over IMHO). Did you really enjoy tearing the solar inverter down, or did you just have a lot of time on your hands?

[EEVblog]

@Dave ,
You really went all out with this teardown compared to, say

( which could have used a bit more going over IMHO). Did you really enjoy tearing the solar inverter down, or did you just have a lot of time on your hands?

Huh? 
Essentially the same effort put into each video.
What more "going over" did you expect?

[ballsystemlord]

Huh? 
Essentially the same effort put into each video.
What more "going over" did you expect?

Don't misunderstand, I'm not trying to accuse you or something. But there were a lot of components in that scope that were unusual. I ended up asking about one item (and I got an answer): https://www.eevblog.com/forum/blog/eevblog-1545-worlds-fastest-oscilloscope-mxo4-teardown/msg4889009/#msg4889009

I was just surprised when I watched that scope video because there were so many unusual components in that scope's build but you didn't spend any time on them. Maybe the scope was just all very normal stuff for you.

Thanks

[EEVblog]

Don't misunderstand, I'm not trying to accuse you or something. But there were a lot of components in that scope that were unusual. I ended up asking about one item (and I got an answer): https://www.eevblog.com/forum/blog/eevblog-1545-worlds-fastest-oscilloscope-mxo4-teardown/msg4889009/#msg4889009
I was just surprised when I watched that scope video because there were so many unusual components in that scope's build but you didn't spend any time on them. Maybe the scope was just all very normal stuff for you.

What is "unusual" to you may not be the least bit unusual or interesting to me.
That blue component you talk about is just an inductor.
I can't possibly look at and explain every component that someone somewhere may not know about. How teardowns work is that I take them apart and whatever immediately comes to my mind as interesting I talk about. There is no planning, no script, when I take the cover off that is literally the first time I have seen it too, and I just yap away at whatever I see. And because I don't have the luxury of a large screen to watch the high definition image back on, I have to rely on my (ageing) eyesight to catch stuff on the tiny camcorder screen. The photo and talking head on screen allows me to see things in more detail, but still I'm only going to talk about things I find interesting in that instance.

[ballsystemlord]

Don't misunderstand, I'm not trying to accuse you or something. But there were a lot of components in that scope that were unusual. I ended up asking about one item (and I got an answer): https://www.eevblog.com/forum/blog/eevblog-1545-worlds-fastest-oscilloscope-mxo4-teardown/msg4889009/#msg4889009
I was just surprised when I watched that scope video because there were so many unusual components in that scope's build but you didn't spend any time on them. Maybe the scope was just all very normal stuff for you.

What is "unusual" to you may not be the least bit unusual or interesting to me.

My use of the word "unusual" was in the objective sense with respect to other oscilloscope teardowns. It wasn't  in the subjective sense which is probably true of everyone else in the whole world. That is to say, everyone will have a different set of stuff which is "usual" and what's not in that group will be "unusual."

That blue component you talk about is just an inductor.
I can't possibly look at and explain every component that someone somewhere may not know about.

Again, most people who look at electronics would be familiar with what caps, resistors, inductors, mosfets, etc, look like. I kinda thought that you spent more time dwelling on the stuff you thought your audience wouldn't be familiar with. Hence, my disappointment at not getting a more thorough going over of the above mentioned scope.

<snip>
And because I don't have the luxury of a large screen to watch the high definition image back on, I have to rely on my (ageing) eyesight to catch stuff on the tiny camcorder screen.
<snip>

Considering you have multiple microscopes, I kinda thought you could overcome many of the difficulties of your poorer eyesight. But even so, I wasn't trying to criticize your poor eyesight. My focus is on a more thorough understanding of the parts used. Many parts these days don't even have part number markings (like those inductors). I'm in the dark here. That's why YT-ers, such as yourself, have such an important role to play.

[EEVblog]

Again, most people who look at electronics would be familiar with what caps, resistors, inductors, mosfets, etc, look like. I kinda thought that you spent more time dwelling on the stuff you thought your audience wouldn't be familiar with. Hence, my disappointment at not getting a more thorough going over of the above mentioned scope.

I have almost a million subscribers, each with a different level of knowledge and interests. Do you really think I can make a teardown video that satisfies every single one of them?
Sorry to tell you, it's literally impossible, someone, somewhere, thousands of them in fact are going to "dissapointed". Welcome to the real world.
So "you get what you get, and you don't get upset".

I've heard it all before "but just do this", "explain this", "explain that", "it's just one little thing!"
Yeah ok, and the end result is a three hour long video where I explain every single component and every single layout choice, and every desing choice, etc etc. And even then I'll still miss something.
What about those people "dissapointed" the video was 41min long? does your "dissapointment" at a lack of something override their dissapointment at a video that has too much stuff in it?

[EEVblog]

UPDATE: Deye have responded and asked me to make this post:

"As an employee of Deye in Australia, I would like to address this issue with complete transparency. Deye, as a globally leading manufacturer of energy storage inverters, has always been committed to providing our customers with cost-effective and high-quality products. Our product failure rates are relatively low compared to our peers in the industry.

During the past couple of years, the pandemic caused significant supply chain challenges, making it difficult to procure certain components while the demand for energy storage solutions surged. To ensure continuous product supply, we had to use alternative components. Please rest assured that all these alternative components are A-grade and have undergone rigorous testing to meet industry standards and certification requirements.

The inconsistency between the components in our products and those mentioned in our catalog is due to our failure to update the catalog （2022-2023 Version）in a timely manner. We sincerely apologize for this oversight. We have taken immediate steps to rectify this and will update our catalog as soon as possible._ "

[ballsystemlord]

> I have almost a million subscribers,...

Dave, you appear to keep coming at this subject from the perspective of me vs. you. You seem to be taking this discussion personally. Neither of the above was ever my intention. Towards the end of reconciling this, and having chosen to use words and failed, I now choose to sit back and give you some time to think about what I have said.

If I had wanted to troll you, complain unreasonably, or anything else, I could have started when I joined here, or in the forum post I linked to above. Suffice it to say that I chose only to ask about one part on one video.

But if anything I say can reach you, then please hear this:
I was part of at YT-ers personal discord. I was among those supporting him straight through to the end of his channel. He focused on the hate, the trolls, etc, and just couldn't take it anymore. They destroyed him from the inside. Please avoid the same destiny which can be done by, among other actions, seeing things in a more charitable light.

[EEVblog]

> I have almost a million subscribers,...

Dave, you appear to keep coming at this subject from the perspective of me vs. you. You seem to be taking this discussion personally. Neither of the above was ever my intention. Towards the end of reconciling this, and having chosen to use words and failed, I now choose to sit back and give you some time to think about what I have said.

If I had wanted to troll you, complain unreasonably, or anything else, I could have started when I joined here, or in the forum post I linked to above. Suffice it to say that I chose only to ask about one part on one video.

But if anything I say can reach you, then please hear this:
I was part of at YT-ers personal discord. I was among those supporting him straight through to the end of his channel. He focused on the hate, the trolls, etc, and just couldn't take it anymore. They destroyed him from the inside. Please avoid the same destiny which can be done by, among other actions, seeing things in a more charitable light.

I've been doing this for 14 years now, and I pride myself on my ability to enagage with my audience like this and explain things and not take it personally. I'm fine. Anything you read into my response as being "personal" is in your own imagination.
I'm trying to explain to you why I can't possibly please every single viewer, it's literally impossible.
I've even done a videos on this:
Starts at 8:10

[ThanhTuan]

Hello! Currently I have an inexplicable problem: when connecting wire N of the grid and wire N of the load together, it causes error F07 in the inverter. Why is it that when I connect to the AC circuit, there is an error (failure) in the DC circuit? What is unusual is why when connected together, the Relay must be broken, but why is the DC circuit broken (error) and reporting F07?