Open Source Arduino Alternator Regulator

[s/v Jedi]

It seems your Vcc is too low? Range is 8.3-13.0V

[markxengineerin]

I can try making Vcc 12V, although the datasheet makes it sound like it's not needed. The schematic is messy in this area- there's a 4.7 uF decoupling capacitor connected so that the chip can supply its own Vcc, the way I'm interpreting

[markxengineerin]

What range of costs/price are you now?

They cost me ~$100 each in the state you see, although I would not call them done yet. In addition to regular debugging, I'd like to improve the connectors, add some sensors and a control /display panel, provide an enclosure or at least a CAD model for DIY starting point. So in the end, maybe sell for $300 each "bare" / $350 "ready to install"? Too soon to know, but I'd like to make some $ to fund similar projects.

[s/v Jedi]

Originally Posted by markxengineerin

I can try making Vcc 12V, although the datasheet makes it sound like it's not needed. The schematic is messy in this area- there's a 4.7 uF decoupling capacitor connected so that the chip can supply its own Vcc, the way I'm interpreting

The reason I come up with Vcc is because it’s often the cause with erratic behavior. Also, it seems they recommend the applied voltage in the range I mentioned as per attached data sheet fragment

[markxengineerin]

After much head scratching, found a missing capacitor forgotten by PCBWay. Thanks Jedi for the effort, onward...

[markxengineerin]

Basic functionality is starting to get checked off


Tested and Working: Manual control of output amps specified over USB connection, measuring alternator temperature with OneWire digital sensor, output alarm, very accurate voltage and current measurements, input switch optical isolators, nothing overheating or burning

Tested and Not Working: RPM from alternator rectifier bridge tap and LM2907 chip- haven't tried to debug yet

Remains to be tested: Serial communication (Victron), CAN, PID / overall control strategy, WIFI app for gauges and settings, OLED display, optimizing field output frequency, ramp rates, getting rid of some noise spikes in the power cables to the regulator. The noise issue is not present when measured at the battery, but nice to fix whatever is causing it.

[haraldh]

I find this development very interesting. I have a Yanmar 1 GM, soon an EVE LF280k 12 V battery with a JK BMS, lead-acid starter battery and I'm going crazy thinking about all the ways I can charge.

My Victron MPPT is fine, connects directly to the LiFePo4 battery. Unresolved are engine and shore power charging. I have the Sterling external regulator on the alternator and a 4-stage 15 A shore power charger (not LiFePo4 capable).

My alternator is the stock 35 A Hitachi and it has been ridden hard with my 220 Ah AGM. I'm not that worried that it would melt while charging an LiFePo4 battery. The power level is just so low ~500 W.

Long story short

Wouldn't it be possible to use an ESP8266, read temperature, starter battery voltage and RPM from the alternator and then use that to externally adjust the maximum current by a Victron Orion XS?

Pluses;

I could ask for 10 A if the RPMS are between 600 and 2000 or more if RPMS are over 2000.
I could ask for less current if the temperature of the alternator rises
I could ask for 10 A if the RPMS are 0 and the starter battery is over 12.8 V (I could use my old charger connected to the starter).
I could upgrade to a 60 A alternator without bogging down the engine at idle or slow rpms.


Is there a way to manipulate the Victron Orion XS externally? This might be off-topic.

[CaptainRivet]

Originally Posted by haraldh

I find this development very interesting. I have a Yanmar 1 GM, soon an EVE LF280k 12 V battery with a JK BMS, lead-acid starter battery and I'm going crazy thinking about all the ways I can charge.

My Victron MPPT is fine, connects directly to the LiFePo4 battery. Unresolved are engine and shore power charging. I have the Sterling external regulator on the alternator and a 4-stage 15 A shore power charger (not LiFePo4 capable).

My alternator is the stock 35 A Hitachi and it has been ridden hard with my 220 Ah AGM. I'm not that worried that it would melt while charging an LiFePo4 battery. The power level is just so low ~500 W.

Long story short

Wouldn't it be possible to use an ESP8266, read temperature, starter battery voltage and RPM from the alternator and then use that to externally adjust the maximum current by a Victron Orion XS?

Pluses;

I could ask for 10 A if the RPMS are between 600 and 2000 or more if RPMS are over 2000.
I could ask for less current if the temperature of the alternator rises
I could ask for 10 A if the RPMS are 0 and the starter battery is over 12.8 V (I could use my old charger connected to the starter).
I could upgrade to a 60 A alternator without bogging down the engine at idle or slow rpms.


Is there a way to manipulate the Victron Orion XS externally? This might be off-topic.

It's time to replace that 35A baby alternator then with a bigger on the 80-100A range that fit and that's modified for external regulation and use this controller here to steer the alternator.

Alternatively get a renogy DC2DC 20A and connect it and use till the little alternator dies. Then either get the same 35A or go to solution above.
An Orion XS is too expensive and too big for your install, that 35A can do 15-20A constant, the orion does 50A.
Everything else makes no sense.

[markxengineerin]

My alternator is the stock 35 A Hitachi and it has been ridden hard with my 220 Ah AGM. I'm not that worried that it would melt while charging an LiFePo4 battery. The power level is just so low ~500 W.

Have you been running this already? Depending on the settings chosen in the Sterling regulator, it might work (?) but I suspect you could also melt the alternator quickly or damage over time with the wrong settings. This is usually what happens when people change to Lithium without appropriately setting up the regulator.

I'm not too familiar with the Orion XS or why you would want to manipulate it externally, but this regulator intended to be a direct replacement for your Sterling regulator, just with more features and adjustability, such as control based on temperature, RPM. Since it's based on a generic ESP32, you have a lot of flexibility to modify it to any unique use cases such as yours.

As an overall update on the project, I have debugged all features besides CAN communication. That's next. There is only one real hardware issue, some noise being fed back to the 12V supply wire (possibly caused by the over-voltage protection circuit) that needs debugging. The noise doesn't cause any functional problems, I just don't like it. So I expect to be ordering the final set of "test pieces" within a month or so- the final units before a first production run. I have done no work on the enclosure(s), external switch panel, or wiring harness yet. TBD if these end up included or DIY.

[s/v Jedi]

Originally Posted by markxengineerin

Have you been running this already? Depending on the settings chosen in the Sterling regulator, it might work (?) but I suspect you could also melt the alternator quickly or damage over time with the wrong settings. This is usually what happens when people change to Lithium without appropriately setting up the regulator.

I'm not too familiar with the Orion XS or why you would want to manipulate it externally, but this regulator intended to be a direct replacement for your Sterling regulator, just with more features and adjustability, such as control based on temperature, RPM. Since it's based on a generic ESP32, you have a lot of flexibility to modify it to any unique use cases such as yours.

As an overall update on the project, I have debugged all features besides CAN communication. That's next. There is only one real hardware issue, some noise being fed back to the 12V supply wire (possibly caused by the over-voltage protection circuit) that needs debugging. The noise doesn't cause any functional problems, I just don't like it. So I expect to be ordering the final set of "test pieces" within a month or so- the final units before a first production run. I have done no work on the enclosure(s), external switch panel, or wiring harness yet. TBD if these end up included or DIY.

Did you use a spectrum analyzer on the noise?

[markxengineerin]

I did, but I didn't save any great screenshots. Here is one I had:


The noise blip measured on 12V power to the regulator (red line) happens every 8.9microseconds. The duration of the event is ~540 nanoseconds or 0.54 microsecond.

It seems unrelated to the field (blue) which looks as expected, although the noise blip gets worse at higher fields. Frequency remains constant always. I can't recall if the duration changes, but I want to say not much, not compared to the magnitude.

If you would like to see something more specific on the scope, I will take some more measurements tomorrow. The EE I'm working with thinks it looks like the battery may be getting disconnected briefly, then reconnecting, due to the protection circuit, but we haven't spent much time on this yet.

[s/v Jedi]

Originally Posted by markxengineerin

I did, but I didn't save any great screenshots. Here is one I had:


The noise blip measured on 12V power to the regulator (red line) happens every 8.9microseconds. The duration of the event is ~540 nanoseconds or 0.54 microsecond.

It seems unrelated to the field (blue) which looks as expected, although the noise blip gets worse at higher fields. Frequency remains constant always. I can't recall if the duration changes, but I want to say not much, not compared to the magnitude.

If you would like to see something more specific on the scope, I will take some more measurements tomorrow. The EE I'm working with thinks it looks like the battery may be getting disconnected briefly, then reconnecting, due to the protection circuit, but we haven't spent much time on this yet.

The spectrum is the lower graph… is red the DC line there?

Edit: do you have a programmable load? (or anything to emulate the battery?)

[markxengineerin]

Yes, the top half of the screenshot has time as the X axis, bottom half has frequency as X axis. But the signals displayed are the same, and the colors match. Red=12V power measured at the Regulator input, Blue is the field output. The choice of scale on the frequency plot may not have been ideal here.

[s/v Jedi]

Originally Posted by markxengineerin

Yes, the top half of the screenshot has time as the X axis, bottom half has frequency as X axis. But the signals displayed are the same, and the colors match. Red=12V power measured at the Regulator input, Blue is the field output. The choice of scale on the frequency plot may not have been ideal here.

So the first pulse in the spectrum at around 110kHz looks to be the strongest?!

Yes it would be better to have a higher range like 5MHz

[markxengineerin]

It is hard to say with the scale, but I will get some better images tomorrow morning. Anything else you'd like measured?