Luna BBSHD Ludicrous V2 controller documentation

[AZguy]

I understand 100-110°C is pushing the bounds of the recommended and perhaps even the absolute maximum ratings for some of the components however this might be a bit of an issue in the extreme heat we see out here. I don't ride frequently when it's that hot but I do get out. I'll sometimes park the bike in the morning and then leave in the worst of it and want to cover several km to get home. It's sort of scary. I always carry a least three or four liters of water when it's like that and get super hydrated before going out and usually soak my shirt down but you can't be out without shade for very long before it's literally life threatening. Always have to count on the potential for the bike failing, especially in the heat, but have never had as much as a burp doing this. I suppose if I go this route I might play with the code...

What do you see as the components that are going to be pushing the limits in the heat? Output transistors may be top of list? Seems like magnets would have to get silly hot to reach curie point but I guess you never know. I suppose the winding's may reach a point were we risk the varnish failing.

[marcos]

The temp cutoff is fairly simple. Nothing is limited below 100°C. Above that motor current is linearly reduced until you get 0 Amps at >110°C. With better (or ar least better known) motor materials and faster temp sensors this could go higher, but we keep it safe-ish.

And yeah, the fact that your motor can be at 80°C just by sitting in the sun is one of the reasons that make it hard to detect for sure if the sensor is the right one. I dont want to have to dump energy into the motor to find out.

[AZguy]

marcos

Quick question on the sensor - maybe somewhere in the thread you've already discussed how the algorithm works and apologies in advance if that's the case

How does this work? At what setpoints do things happen?

One reason I ask is that here in AZ the ambient air temperature gets 50+°C - we're just getting into that season with 47-48°C projected for next week and so close to the ground likely be that 50+°C... if you add solar loading with the bike parked in the sun even before turning the bike on 80°C motor temperature may not out of the question before the motor is even powered up

I am silly enough to ride in that stuff [although don't recommend it] and it's usually no more than 4-5km although I could easily see 10km or so

[marcos]

Heads up!

The last batch of BBSHD's coming from Bafang came with a wildly different motor temperature sensor. The Ludi V2 (and any aftermarket controller) will measure the motor temp incorrectly and motor overtemperature protection won't work.

The way to check if you have a bad sensor is opening the vesc tool app and checking the motor temperature gauge. If it shows something ridiculous like 80°C when you haven't used the bike yet, well, thats a wrong sensor. It even works backwrds: the hotter the motor is, the lower temps are read. I coded support for the new sensor, but I don't know how to reliably detect which one the motor has so you have to check.

I thought this bbshd+v2 combo didn't exist in the wild, but yesterday we got a user with a toasty motor caused by this sensor change. The banana bikes sold have these new bbshd but the nylon gear and temp sensor are upgraded at luna before shipping out.

[BUD WHITE]

I bought the battery from Litespeed batteries out in New Jersey.

[BUD WHITE]

I bought it from Litespeed Batteries out in New Jersey. He has a 72v triangle that is perfect for the V2 with 18ah and 180 amp continuous. Cheers.

[Bobster]

where did you buy your battery from?

[xcnick]

I hope you will revisit the idea of the throttle power tied to the PAS level. I am trying to get used to it, but I have too many years the other way. Now when I blip the throttle to get over a curb, rock, etc. I don't really know what to expect. A blip of the throttle at level two is very underwhelming and over the handlebars I go.

[marcos]

Nope, sorry. The bafang controller is a black box, we have no control over that firmware :/

[xcnick]

Your pedal assist settings are wonderful. Is there any way I can reproduce that with a normal or version one ludicrous controller?

[marcos]

I just reproduced all your steps starting from the 72V image I sent you. After the initial USB-programming I see the controller identify itself as a 72V_POWER_WOLF:



Then I flashed a 52V_WOLF, and when I reconnect (and also when I powercycle the controller) the correct 52v wolf firmware is shown:



I tested flashing a DIRE WOLF firmware and its also correctly displayed

[marcos]

Sure, let me check the images in the morning

[StvMan]

Perfect...thank you.

[marcos]

Yes, it stems from the same principle. Lets say the BBSHD can take 50 phase Amps all day long. Now if you are on a 52V system lets say that would make 1500W.

Now increase the voltage 4 times, to 200V @ the same 50 phase Amps. The motor will experience pretty much the same temp increase, driven by I²R winding losses but your power increased 4 times. Your speed also increased x4 so you will want a shorter gearing. This a pretty extreme example, so extreme that iron losses and gearing losses would start to creep in, but it helps explaining that the 72V system can sustain more power for the same motor heating.

Similarly, power delivered at low RPM is relying on high motor currents at low motor voltage (P=V*I). Power delivered at high RPM uses high voltage and low (motor-heating) current.

[xcnick]

Try this guy's. I Flash Wolf. When I reconnect it is still Wolf. If I turn off the bike then turn the bike back on it will not show Wolf but dire wolf as the firmware. I don't think it's really dire Wolf, it's just as the 1st choice of the 3. But I am worried I have the right Flash.