ElectricMotorcycleForum.com
Tech => Home Brew => Topic started by: craigster on August 03, 2017, 07:12:34 AM
-
Hi all,
Wondering if anyone knew a way for me to get a Zero motorcycle to fully operate, whilst plugged in and charging (theoretically like if I was towing a generator). Need your help!
Thanks!
-
Electrically, this is not a problem, but it'll be best to connect to the controller to power the motor in parallel than to try charging the battery while riding. The motor output of >6kW at 55mph ensures a 0.6C rate of discharge which most mobile generators can't match at all. So it's better to arrange the circuit this way to minimize current flow on any circuit.
Also, the generator output will be less than regen typically.
But more to the point, can this generator emit the right DC voltage instead of wasting AC on a switching power supply?
And can you arrange the connection to avoid cable wear, motion, and provide for emergency disconnect?
-
thanks for the reply. I was thinking that too - going straight to the controller, however generators like to run at constant rpm and output, if I were say going from idle to 55mph like you say I don't know if the generator would be able to handle such fast transitions in power demand. I am still just learning about all of this, its for a school project so any help is appreciated. Let me know what you think
-
thanks for the reply. I was thinking that too - going straight to the controller, however generators like to run at constant rpm and output, if I were say going from idle to 55mph like you say I don't know if the generator would be able to handle such fast transitions in power demand. I am still just learning about all of this, its for a school project so any help is appreciated. Let me know what you think
Running the cables to the controller should not couple the generator to the motor's power demand. The battery and controller are connected to one circuit while running, and the battery will accept power back into it, usually via regenerative braking, but an additional generator on the same "bus" would have the same effect.
Basically, the controller terminals are just the best point to join a generator to this system to keep all of the power involved within the rated capacity.
However, I think you will have to carefully figure out how to get a generator to produce DC in a range compatible with the battery, though, and how to implement circuit protections so that these 3 major items (battery, motor controller, and generator) all play well together. In the worst case, I'd expect that the generator deserves a controller (Arduino-level capable) that connected to the CANbus, read out system voltage, regulated the generator to match that and act like a CC-CV charger (constant output current until matching the battery's top static voltage, at which point to reduce until cutting off as needed). The CV taper/cutoff behavior would have to be dynamic especially at high states of charge because regenerative braking might cause voltage to rise quickly.
-
I think your idea is very good.
-
I should say for anyone reading that this almost assuredly would invalidate warranty repair coverage if the arrangement causes damage. Connecting power supplies in any way requires a professional mindset, research, and safeguards.
This might destroy the connecting lugs, or damage the generator or the controller, if implemented without a real load-sharing plan in mind with maybe an extra controller to manage the generator.
-
I am now considering that idea too as i'm planning a long trip to the north of Quebec where there is lake and forest for multiple hundred miles without any house, grid or any presense. The longest part of my trip is about 400km right to the north and as it is not a paved road, but it is just rough gravel i expect to do about 200km max si i will ned a second powersource than battery.
Connecting a generator is the only way unless i make the TERRY mod with expensive additional battery witch i dont have now.
A 4kw generator and running at a power of 8kW should double my range and do the 400km.
Did anyone succeded to run the SCv2 output without being connected to the brown connector on the Zero?.. Because it is obvious that charging while riding require to not have the Zero to detect the presense of the charger, so it must be connected to the controler and require the scv2 to be trigerred anyway.
Doc
-
Did anyone succeded to run the SCv2 output without being connected to the brown connector on the Zero?.. Because it is obvious that charging while riding require to not have the Zero to detect the presense of the charger, so it must be connected to the controler and require the scv2 to be trigerred anyway.
Hey Doc, I guess I'm not seeing the problem. If the bike is keyed on, the contactor is by definition closed, so you should be able to charge through the Anderson connector, period. I don't think the SCv2 requires any handshaking or anything to fire up, and I can't see why you couldn't just run current into the battery (via the Anderson connector, direct connection to the motor controller, or however) while the bike is running. I don't think the bike has any way to know (or would care) that there's current coming in from off the bike. You would just be reducing the current draw from the battery to move the bike, or (with a more powerful generator/charger or lower consumption) even actually charging while riding.
What the SoC firmware will display under those circumstances is anybody's guess. It doesn't work right under ideal conditions, it certainly isn't going to work under oddball conditions like that.
-
SCv2 can easily be connected to the controller terminals, and it is best to do so, because it will minimize the amount of current flowing through the cables.
The motor, when supplied with power from any other power source, will draw less current from the battery.
SoC calculations would then depend on where current is sensed. If it were just one battery, it'd be defined by that battery's BMS. With a Power Tank, maybe it's less clear, but I would hope the current sensors are relative to the battery and not to the controller or motor.
I think the only problem is to run the generator so that it could operate in a stable way despite a variable load or a shifting load (mostly the load is the motor, until there's regen and then it's the battery, and then it'd have to transition to idle without lurching). Or, basically what I said above.
-
SCv2 can easily be connected to the controller terminals, and it is best to do so, because it will minimize the amount of current flowing through the cables.
The motor, when supplied with power from any other power source, will draw less current from the battery.
SoC calculations would then depend on where current is sensed. If it were just one battery, it'd be defined by that battery's BMS. With a Power Tank, maybe it's less clear, but I would hope the current sensors are relative to the battery and not to the controller or motor.
I think the only problem is to run the generator so that it could operate in a stable way despite a variable load or a shifting load (mostly the load is the motor, until there's regen and then it's the battery, and then it'd have to transition to idle without lurching). Or, basically what I said above.
I know I am tardy to this party, but the load on the generator will not shift as much as you think. The generator creates AC, that is rectified down to DC and fed to the DC-DC converter, in this case a supercharger brick.
The supercharger is just trying to maintain the full voltage, or the full current. Its likely the bike is not fully charged, so the full output current is the limiting factor. when you're on the throttle, the voltage may dip, but the power draw from the DC-DC input stays the same. the generator load doesnt change. Its always pulling the same 3.x kw... the load might even go down under throttle, if you really nailed it, because if the battery voltage sags enough with constant DC-DC output current, the power drops. so the load on the generator is lower under load... However the load change on the generator is all voltage dependent. and we know the voltage of the zero doesnt change that much under normal riding conditions.
-
SCv2 can easily be connected to the controller terminals, and it is best to do so, because it will minimize the amount of current flowing through the cables.
The motor, when supplied with power from any other power source, will draw less current from the battery.
SoC calculations would then depend on where current is sensed. If it were just one battery, it'd be defined by that battery's BMS. With a Power Tank, maybe it's less clear, but I would hope the current sensors are relative to the battery and not to the controller or motor.
I think the only problem is to run the generator so that it could operate in a stable way despite a variable load or a shifting load (mostly the load is the motor, until there's regen and then it's the battery, and then it'd have to transition to idle without lurching). Or, basically what I said above.
I know I am tardy to this party, but the load on the generator will not shift as much as you think. The generator creates AC, that is rectified down to DC and fed to the DC-DC converter, in this case a supercharger brick.
The supercharger is just trying to maintain the full voltage, or the full current. Its likely the bike is not fully charged, so the full output current is the limiting factor. when you're on the throttle, the voltage may dip, but the power draw from the DC-DC input stays the same. the generator load doesnt change. Its always pulling the same 3.x kw... the load might even go down under throttle, if you really nailed it, because if the battery voltage sags enough with constant DC-DC output current, the power drops. so the load on the generator is lower under load... However the load change on the generator is all voltage dependent. and we know the voltage of the zero doesnt change that much under normal riding conditions.
Oh, I did not interpret this as going through a supercharger brick. With a supercharger acting as a (self-regulating) DC-DC converter, you're absolutely right.
-
Any updates on this item?
Very interesting thinking in this topic.
-
I want to be clear that this has always been inadvisable, and any doubt expressed about that is due to it being theoretically possible and achievable.
The most likely scenario for anyone reading this is that you will cause yourself harm or injury, or you will damage the powertrain.
This is not something anyone should do with their own personal transportation if they cannot handle all the possible failure modes.
-
Can’t help but be be reminded of this concept by Alta (https://www.popsci.com/special-forces-stealth-motorcycle-silent-hawk) Sorry, I know it’s not the same thing, and never going to happen for them of course, but such a feasible build...
-
Just out of curiosity, if DC generators were readily available, what voltage would it need to be to work on this project as asked by the OP?
There are some 12 V DC generators available but I recon that voltage (even at a high amperage) would be way too low, right?
-
I think another Zero motor, Sevcon controller, and 250cc+ motorcycle engine (essentially regenerating) would be the best way to do this for weight and compact design. The only generators that produce 6kw&+ that weigh little enough to be pulled by a Zero without increasing demand are crazy expensive and in use by the military to power UAVs. turbodiesel and high-altitude air-cooled. 3 Honda EU2200's would also approach this.
While it would be interesting to see, there are far better ways to make a hybrid bike and the equivalent mpg this would result in (40-60mpg) is kind of atrocious for the level of work involved.
-
While it would be interesting to see, there are far better ways to make a hybrid bike and the equivalent mpg this would result in (40-60mpg) is kind of atrocious for the level of work involved.
Agreed, it's a wild goose chase, but if nothing else it would shut up the "range anxiety" people for the occasional exceptional need. You could ride 500 miles to Aunt Mabel's house for thanksgiving, at least in theory.
-
How about a tail gator generator that runs the on board charger to charge one of the two bricks on a fx. 600w will take 5 hours for one brick. Now to make a zero fx run for five hours on one brick. I don’t think the epa would like a two stroke engine powering a electric hybrid ev.
-
What if you ran a generator with it's own controller that would directly charge a set of capacitors 1 at a time and auto switch recharging of capacitors. They may only run a short time but you would have phenomenal power, range would depend on the size of gas tank of the generator. Your capacitor refill time should be short as well. That way generator isnt charging the unit powering the bike.
Sent from my SM-G930P using Tapatalk
-
If a generator ran for 10 hours on a gallon of gas, and you got 20 miles on each capacitor recharge that took 20 minutes to charge.. isnt that about 500-600 mpg?
Sent from my SM-G930P using Tapatalk
-
And that would be at any speed you like as long as there is gas in the tank right?
Sent from my SM-G930P using Tapatalk
-
The merits of ICE are wandering off-topic. For the purposes of discussion let's not dwell on the energy density of petrol...
-
The question has already been answered fully:
- Connecting to the controller DC lugs through a switching power supply would supply current to the bus while riding or not.
- You cannot charge the battery while riding without exceeding the current demand of the motor. (6kW for most practical purposes)
Anything else is pure speculation and deserves a new thread.
-
Just trying to help out. I'll leave it to you geniuses. Out.
Sent from my SM-G930P using Tapatalk
-
It’s not about new comments, although I’d rather keep this thread dead.
The trouble is that everyone wants to make a hybrid, when even the OEMs can’t deliver that. Any attempt at it will be expensive and dangerous if not designed and implemented professionally.
-
How in professional is this idea. Why don’t we plug A/C current into the sevcon and make it charge the batteries. Would we need the make of it one phase into three or 120V too high already. There hasn’t be a way to make the sevcon regen on 120v 60hz. 100hz would be 6000rpm.
-
How in professional is this idea. Why don’t we plug A/C current into the sevcon and make it charge the batteries. Would we need the make of it one phase into three or 120V too high already. There hasn’t be a way to make the sevcon regen on 120v 60hz. 100hz would be 6000rpm.
Make a new thread for that. It’s off topic here.