A gentleman called tinyt did the circuit diagram for everyone, ( I don't do diagrams/schematics, I just design in the pcb program... so I'm useless like that )..... but everyone apparently needs them, whereas the boards do all the work for you... who knew...
Powerboard
Control board
IMPORTANT!! The diode D6 is listed as a zenner of 13v... it is in fact 18v. If you use 13v you will lack enough drive for the fets... USE 18v for this not 13v
The pin 6 of the 8010..... When you put the 8010 on the daughter board, make pin 6 stick up not down. We will use this for the take off point for the on/off switch ( labelled as spwmen. Do not put the pin on this pin down or you won't be able to turn it off. I originally used the temp pins for on/off, so this pin was permanently 5v, by putting the pin up we can use a lead to the switch, and spwmen then goes to ground for off or + 5v for on.
or pdf here
2018-02-12_151253_OZINVERTER_POWER_BOARD_SCHEMATIC5000AW.PCB(1).pdf (24.58 kB - downloaded 544 times.)
and here
2018-05-04_074827_Oztules_Control_PCB_and_Power_Board_Schematics.pdf (49.63 kB - downloaded 578 times.)
So there are the circuits for the two main boards, the fan control is best shown here perhaps.... no circuit, but self explanatory.
I'm too lazy to do the BOM.... all the component values are on the boards.... use the gerber viewer to see the top overlays for the parts or the schematics.
The schematic depicts 6 big caps, it actually uses four on this unit, and the two center caps is actually one single 4uf ceramic cap for high frequency suppression on the bulk caps... but that's the only ,mistake on the schematic I can see at this point in time.
I now use the Chinese HY4008 fets . They are very very very good... much better than the irf4110, and come in a decent sized case too. They easily ( 4 of them per leg) run the 20kw start up currents for the big induction motors and everything else. I used to use 6x4110 per leg, but the HY4008 is a better unit I think. On Aliexpress they are only a dollar or so USD..... simply brilliant value. I test them on arrival, and all fall within specs... and look at those specs....
Just a single fet per leg will do 2kw all day long... darn impressive...
Here is a pic of the fan control and the buck converter from ebay ( 10 amps@12v for about 8 dollars )
It is very very wise to use a few 68amp o/loads on the input from the battery to soften the blow if you should blow the thing up somehow. If you do like I did in testing, and you have the breakers ( NOT FUSE) in line, you will only damage a leg or two of fets with no board burn, and probably not even the drivers, no smoke and no tracks exploding. Without the breakers, the fets sequentially pop one after another until they and everything attatched is destroyed, and no path for the battery can any longer get through... this includes tracks. This is all stopped by the application of 5 dollar breakers.
If you question the manufacturers, they will tell you that you can use these AC breakers at voltages less than 60v with about a 10% derating DC breakers are expensive and will do no better.
There is a drawback ( there is always a drawback). When you attatch the battery and hit the breakers to energise the unit, it will likely weld the contacts together on some brands... it depends on the internal structure. It does not make a difference if it is DC or AC breakers, they will have to contend with over600 amps on battery connection..... the caps are that big, and the power is huge to charge them up instantly.... be warned.
So use a resistor of say 8 ohms, in series with the battery lead you connect or bridge the OPEN breakers with the resistor. It will charge the caps in a second or two with no pyrotechniks.... very sedate, then throw the breakers, and then turn on the on/off switch. The inrush currents are absolutely brutal.
Now this presents another problem... the unit will probably not run, and the indicator light may or may not light. It is controlled by the 8010, and it does not like soft slow ramping up of it's 5v... so it hangs. We have a reset switch for this very reason ( amongst others, like o/current events). Sowe now know that a slow ramp up will likely result in nothing happening.
Reset in this context is a press switch shorting out the 48v input AFTER the 120r resistor. This will result in the power to the 8010 dropping to zero, and then when you release the switch, it gets it's instant fix of 5v, and is happy thereafter. It is IMPORTANT to note that you press the switch with intent... a very fast contact will result in not all the voltage being shorted, and can confuse things , maybe even resulting if fet burn. So hold it for 1/4 second or so when you reset at any time. .. and all will be well. I did not ever notice this as I always used a press switch, but some time back a bloke simply stuck a screwdriver across the resistor to ground with a glancing touch. This blew the fets...... so we now know.
The torroid transfromer takes no prisoners, and will not tolerate a rapid change to the internal flux, and will resist totally. This means any rapid change to the frequency ( instant sort of thing) will result in the back emf blowing the fets. This only happens if you mess with the timing somehow. I found originally, the on board current reset on the 8010 did not take this into account, so the native current control, almost always blew the fets, as the 8010 changed gears, and the drivers did not do a soft change... bang...
This also caused the power jacks the same problem when they came off shore power battery charging, when the chip resumed the 50.0 hz from the say 51hz of the source, this change would be fine in a normal E-I transformer, as there is enough leakage to absorb the shock, but big torroids just blow everything up if you try that.
All that makes these things sound finnicky, but they are not, I'm just telling you what can go wrong. With 16 or so of them out in the field for years, there have been only two failures in probably 40 inverter years of use in the hands of novice users running households with everything going. The two failures were user initiated... letting the units run down in the 40v range in a high power instance ( yes the batteries were run flat).
So if you open the pulse width to max, and don't have the battery to support it, there is a chance of failure. Beyond that they have taken anything and everything these folks have done to them... they really are tough, but getting the battery hooked up is finnicky the first time, unless you have a very big switch that can handle the turn on current, or just splat the terminals ( that works fine, just scary.
So the take away is this....... do use breakers, even though that is inconvenient the first time connect. The chip may hang on the slow start, the reset sorts that out so no problem anyway.
Can we reset under high power....... yes if you want.
Can we start under high loads ( say 8kw load on line before we press start ) yes, no problem starting under full load. ( Once,after the front 20 amp AC o/load threw I just went out and reset it..... it restarted, and the read out showed why the 20a o/load went..... it was starting up under 8kw load. The 20a o/load can do that for a minute or two, then throws)
So we know the instant/surge loads can exceed well past 20kw, and we can sustain 8kw too. Your cooling and heat sink design will dictate how far you can push it. Some folks have huge heat sinks, and can run 5kw for 30mins, and the fans still don't come on..... so efficiency is pretty good.
Grid tie inverters work well with these as well. We have run 8kw backwards through them to charge the batteries, and now a few Queenslanders do this all the time, as it allows for high voltage arrays at a distance, and the GTI can help run the house during the days with the air conditioning on all day, this takes some of the pressure off the batteries and the inverter.
They seem to run the airconditioners all day and night. So the GTI runs them, and the inverter runs the excess( if any) back into the battery. It does this via the synchronous switching of the mosfets, and this happens to make the transformer into a boost converter in these instances, and is why the tranny which is really a 28v transformer for a 48v system, be able to charge the battery to beyond 62v or more with just the 240v input. The sychnonous switching in conjunction with the transformer is responsible for this behavior.
These inverters have a very very stable output. If you watch the lights, then switch in a jug or something else of a few kw, there is no flicker... at all.... remarkable really, but it stops the GTI from turning off from over AC voltage, which the powerjack did, as it let the AC rise if the battery was full, so it sort of controlled the charge ( brutally, but worked), but these things have such a stable output, that does not work, so we developed a new GTI controller for that aspect ( another article perhaps).
The use of an inductor will decrease the idle power consumption very considerably... around the 13-20uH seems to be enough to do it. ( three turns around a etd65 core is enough to do the job).
It does not matter if it saturates or not. You can design a biggie if you want to avoid saturation, but you will notice no improvement. It is only used by me to quench the high speed current surge whilst driving the pulse width up. ie as the fets turns on, this inductor will impede the current just enough for the switch to turn on fully...... this means a 5kwh/day idle current turns into maybe .4kwh/day. It makes that much difference. It must also help the shock the silicon sees too.
Some folks have made beautiful inductors that do a little better too.
Thats enough waffle for this post.
.......oztules