I wish all the teardowns been like that! Only correct and clear information, no blah-blah talking 👍

Seems like a decent inverter. You can see where corners were cut to save cost, but over all, it seems to be a well designed inverter. Nothing too fancy, just something that can get the job done.

本人吹き替えなのがすごくいい。しかも今まで人に吹き替えてもらってたのが謎になるレベルに流暢。

I'm still amazed by how much current those tiny 'transistors' can handle. Not only in this tiny converter but also in our grid, running at 800kV DC/AC 380kV bidirectional converting at kiloamps.

Thanks. Some comments : It is in general possible to place power mosfets in parallel and many power mosfets have an internal structure based on fets in parallel. Furthermore rdson has a positive temperature coefficient so when one heats up the cooler ones process most of the current. Any series resistors help to maintain the balance and that might be the reason for the smaller busbar. As for the electrolytic capacitors, lifespan is about halved for each 10 degree celcius up in temperature ( rule of thumb ... might apply more or less ). I guess that's a very limitting factor for the life span of this inverter. The film capacitor is a way better option. Great video .. make more .....

Great for me that you have English-speaking version. I guess the pink sheet attached on one side of the rubber is a thermal interface material. It's used for sharing heat between caps and for easier removing heat out from the caps, to lengthen the caps' life.

All things considered they did a good job for the design. I was expecting worse

There is a reason for many US brand components in this inverter. If this board is an early revision, they make small batches, so relatively low volume western components in china are abt. the same price. Chinese 1st party sellers dont like to sell less than around 10~20k. Some manufactures start with small batches with western components and change te BOM to chinese made ones when scale up. Probably all those components are chosen bc. they have drop-in replacements for it. The TMS320 for examples have many drop-in clones. Majority of inverters use cheap TI DSP clones.. Dont subestimate those eletrolytic caps, this things are harder to make than us think. that's why nippon chemicon, and murata are market leaders. Eletrolytic caps looks like simple devices but very hard to make it right.

Very good video. Easy to understand. Clear speech. I like that you were thinking what to say beforehand instead of coming up with words live.

please give us more of this type of content! much appreciation for such work!

Excellent overview! You gave just the right amount of detail while keeping the content interesting and enteraining!

Excellent description, very clear and understandable, thank you!

Wow! Very high quality content! Immediately subscribed!

This guys knows this entirely. Subscribed.

Great video, I have seen similar topology in fire damaged BMW inverters.

Thank you for tearing down and explanations, very nice presentation.

such a great and informative video

You could talk about the topology of the gate and power driver MOSFET paralleled H-bridge to be activated simultaneously and how it makes it to have no noise

fantastic explanation,waiting for more stuff like this ! thank you brother

great video! glad the algorithm showed me this!

What’s crazy is I only see 500.00-600.00 worth of components/pcb/aluminium. How companies can get away with ripping people off is beyond me.

Thank you and thank you professor!!😁❤

Great video, well explained, excellent job.

I can't believe how small those power transistors are. I've seen larger Silicon IGBTs in e-bikes.

Excellent video.

real otaku with master electrical engineering

Outstanding video

Amazing teardown and break down man. I am impressed by the quality of your content. Another reason why the car inverter components might be spaced a bit further could be the higher operating voltage of the car inverter.

I'll support also this channel from Japan with respecting for both Ichiken and Denki Otaku :D

incredible how they made this thanks for explaining

I had no idea there was another channel for Ichiken.😊

I have learned from the video, thank you.

Thanks! Well done.

Brilliant... These TI controllers are used in lots of inverter stuff, lots of the functionality you would normally have to realize with discrete logic and circuitry is already inside including protection and hardware comparators - even if their operation is not trivial, deriving from an existing product is not that big effort. They are also available in multicore configuration driving highly integrated and protected solar converters. It would be interesting which switching frequency is realized... The controller has advanced ADCs which can run synchronous to switching frequency, the CLA coprocessor can preprocess the acquired samples and offload the core. Its a proprietary TI 32 Bit architecture with FPU, the CLA coprocessor can also operate floating point values. Weird Harvard architecture... perfect.

Otaku-san, you've been added to my subscriptions. It's hard to come by channels like yours.

Well done, thanks.

you won a subscriber, amazing content

Great video, thank you and your professor. One thing I noticed about the power board: there is room for double amount of mosfets, which might suggest that there is possibility of making larger power version, even the gate resistors are mounted, maybe with larger size heatsink or even water cooling plate..

Excelent video.

Muy buen video, gracias por la traducción

Sehr gut! Danke

Awesome👍

i love cost effective evs and their parts

Thanks for this video

Good explanation. Brazil.

2:50 notice that the first capacitor from bottom to top is already bloated!

Thanks.

Great video! I would be very interested if you do a similar teardown to various UPS units or other battery backup systems.

🇧🇷.Muito boa Explicação...👍

Nice.

A tip I have learned for reading difficult product numbers it to keep the ic and microscope stationary while moving the light source around at different angle and distances. If this doesn't work I found you can angle the pcb at 30° away from you and angle the light source. You will see the engraving will light up eventually.

Thanks for such a great explanation of the Inverter for use in a small EV Car. For me, it was interesting to see how the 22 - Electrolytic Caps were used, instead of one larger type. I also wondered if the Inverter had any thermal shut-down protection circuit, and also any (replaceable) Internal Solid-State Fuses for protection. In your opinion, would the failure point of this Inverter be those 22 Capacitors - as they dry-up and get old? I am not an expert, but Electrolytic Capacitors do seem to have a limited life, and their replacement could greatly extend the Inverters' life. Greetings from Australia.

Great tear down. I'm going to make an educated guess that thicker busbar is due to the two rows of FETs mounted back to back and not much thermal area on the board to dissipate heat. With that larger, what looks like aluminum, busbar it helps remove heat.

I was *not* expecting to see Infineon MOSFETs on a low-cost Chinese inverter like this!

Plz provide details of the controller part as well, like the TI and ST micro controllers and the driver as well

I was going to remark that using standard electrolytic capacitors was a cheap-out choice for something like this because they age over time (especially in hot/adverse conditions) and are more likely to fail than other types, but I guess in a car this cheap they're willing to accept that eventuality. The pink sheet is definitely designed to be thermally conductive, although it might also provide some vibration dampening as a side effect. I doubt the sheet conducts all _that_ much heat out of the capacitors in practice because of how thick it is, although it is better than nothing. MOSFETs connected in parallel tend to give somewhat balanced results, because MOSFETs have a positive resistance coefficient with temperature. If a MOSFET is carrying more current it will heat up more, which will increase the resistance along the channel, so more current will flow through the other paralleled MOSFETs. This is reasonably self-stabilizing, so no runaway should occur where one MOSFET is handling all of the current. Of course, this is not perfect so you can't run your transistors right at the bleeding edge of their current ratings if you're relying on this to ensure stable operation.

Neat!

imagine the parts from this being available to the rest of the world to convert existing cars to electric. much of the EV on road costs are due to certifcations. engine swaps can be certified cheaply, there are thousands of local mechanics capable of swapping drivetrains etc. optimistic? maybe. Doable? yes?

Two current sensors is usual to industrial inverters, just a few exceptions like Danfoss use 3 sensors

Any chance we could get more details on how the board to board connections are made? I've been taught that creep in the PCB material will make a bolted joint like that loose preload over time, do they have some kind of spring on the fasteners to account for that? Also, are the connecting rings really aluminum? If so do they have some way of avoiding bad contact due to the natural passivation layer?

What is the chip in the metal case on the second board?

I like that you point out US made chips are more reliable even if slight more costly

great content, u have yet another subscribe from a western guy

The drivetrain from one of these vehicles seems convenient for reuse in electric boat conversions.

Here we see Einstein talking about the making of an atomic bomb

Texas Instruments and many western manufactures? The sanctions dont seem to work at all :D

What gatedriver was there in the 2.one for fork lift?

Interesting video, what's the reason for having 6 MOSFETs in parallel instead of having just 1?

you forgot to mention the controller board that all components are assembled on one side and the other is full of test point. You can see Curtis inverter use aluminum casting and the automobile use CNC extrusion aluminum for heatsink.

Deeper drive into topology would be appreciated.

👍👍

Most Inverters fail due to semiconductor blowing up, so choosing an european Brand like Infinion seems legit and in the end cheaper - if you have to swap all the inverters due to failure, it will cost you a lot of many, especially if you sell many of them. If you demand the same quality standard like in Europe (or with lower standards, but still rather high like in america compared to chinese cheap mass-production standards), the prices between european and chinese products are basically the same, especially with products which don't need that much man-power for the manufacturing.

Similar layout I have seen on Electric Forklifts (Hyster)

What is the switching frequency of the inverter? Is it near pure sinus or rectangular AC output? How is speed/power controlled via amplitude of voltage or PWM like?

Looks like they left open pads on the board to have the option to add more or less MOSFETS to adjust current-handling capability. Still, I definitely would have gone with IGBTs. This circuit looks like something you'd see on Instructables when searching "how to build an inverter".

Mosfets can easily be paralleled due to positive temp coeff which results in equal current distribution. But nice teardown.

Which inverter topology is used?

So if i use power jack to move pallet of potatoes, does this such controller use them sensors to demand more amps? move something light motor is chill.

Is there CANBUS communication between inverter and Motor and battery.

The current sensors somehow seems to me of the Rogowski coil type... Maybe they are hybrid with an additional Hall sensor.

usage of aluminum collars for high current interconnect in-between pcb layers is a bad engineering decision. Aluminum oxidizes over time and the contact will weaken, possibly melting the board or even causing electric arc and fire. Actually at 8:40 you can see the result of chemical reaction in-between copper and aluminum around the collars, spreading around the PCB. So even in a brand new inverter you get damage already there, and you can see that as contamination creeps around the PCB it will make the device broken beyond repair very soon. Remember both copper and aluminum are alloys, and the least noble metal will surface out and be leached with moisture. Losing alloy elements will also cause alloy to be brittle.

The TMS320 is 12 or 16 bit if I remember correctly

es gibt Hybridmodule wo die ganze Technik schon eingebaut ist. sehr kompakt. IBCs heisen die.

Frankly for the cost the vehicle, the design seems to be of good value, I am surprised they didn't use slightly better electrolytics but I suppose there are a lot of them.

It is not a 20kw inverter. Inverter rating is at constant output. So it is 14 kw. But going by the size it would be lucky to do 10 kw

next video, scope the sine wave

11:56 I would expect them to be equal

هل استخدامهم لتقنية cree mosfet يعطي مردود أفضل بالحجم والحرارة

Amazing how this can actually handle 20 kw

whats the topology of the inverter? clascial 3 phase H-bridge?

If someone had given me that assembly and said "guess the power rating", I think I would have said 2-3kW, perhaps 5kW peak. I can't help wondering how long this unit will last - particularly those Al-Cu compression fittings.

The box is very big compare to pcb. So we pay for the box more expensive than pcb.

Where can I buy some?

Smaller electrolytic capacitors are also more likely to be more readily available hence cheaper and if one starts to fail there are many others to share the load. Electrolytic caps are a failure point so why risk the system go down ? Industrial inverters have been around a long time and so are pretty well proven. You might be overthinking the cooling - the inverter will have a track record and they will be pretty sure what its capabilities (and weaknesses) are and any alterations would be pretty well thought out and implemented already elsewhere. I haven't worked in power electronics for a long time but I would be surprise if the layout is not replicated across many electric car inverters. The car industry tends to be pretty conservative - read hanging on to old technology which works as long as it can 😊.

That looks like a rather minimal current-carrying capacity for 140 amps! I was expecting like four times the cross-section to the major conductors. Flimsy and IMHO it's gonna overheat and fail within a year.

I'd like to think back to my scrap LCD display that was scrapped after 5 years due to the capacitors failing. Got it for nothing. Soldered in new capacitors, by doing so, got a new display for my PC for cheap. But in freaking cars... Talk about waste. Not everyone will fix them, and if it isn't economically viable..

Today i learned that capacitors have pressure release valve

It would have been nice to show an oscilloscope trace of the “U”, “V”, and “W” phase outputs.

I wonder if I can use this to drive a 3 phase lathe or mill by using batt back up system

Yes! 電気オタク. You should link to the Japanese versions so people like me who are 電気 and 日本語 otakus can watch both versions :)