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[winfried]

I am sure anyone already had the idea using the motor controller as charger ( I hope I do not double a topic).

Just saw Stream #0 from Zero: carrying the fast charger infrastructure is not the future  (also read this before on other articles and posts). Charging is controlling the DC input current and limit the max voltage to batteries, currently done by AC/DC converters build-in or fast charging with extra gear...
But, there is already another charger on board, the regenerative charger in the motor controller, which takes 3 phases AC from motor and charge the batteries.

So my vision:
 Unconnect the motor from the controller, take a 3 phase outlet (from type-2 or any other 3 phase source) plug it into the controller when the motorcycle is switched on and it does an "regen charge" at full rate. 

Of course it needs some additional tricks, but could i be a solution for fast charging ?
Maybe for future bikes and bike controller ?

Evcon supports to set the regen parameter (battery current limit), but I don't know if it takes high voltages and how the regenerative charging is limited.

winfried

[frodus]

Not sure it would work well without something to decrease the voltage from the 170V peak to peak, to something under the 116V max of the controller.

[Burton]

The problem is the encoder. Our bikes use one to know what the motor is doing and it is calibrated to work with that motor only.

Haven't looked at the programing to know if you could simply ignore this signal and feed in 3 phase AC.

I do however charge DC through my controller to bypass the small fuse in the 2013 with DC up to 90 amps without changing settings if I recall (would have to double check as stock might be 40 amps)

[Doctorbass]

That principle exist already.... At least for charging from DC to DC. The Adaptto e-bike controller have the option that use a charge coil as a boost converter to raise the voltage to the desired battery voltage.
I have two of these great controllers here. I can apply even as low as 12V and get 92V CC-CV at up to 3-4kW...  It use one of the 3 phase output to control the current on the positive input  combined with a negative wire that is after the internal current sense shunt to measure it. It work really well.

Now the same principle would be great but by using two of the phase input and to switch the mosfet as a rectifier to convert AC to DC. but the controller would have to use at least 200V fets to take the 170V peak of the AC 120V and 400V fet ... or even IGBT to take the 240V ac...

HEre is an exemple of my ebike with the adaptto charging from a 1.8kW server power supply and my J1772.:




Doc

[nigezero]

Genius, Doc. Love your work.

[arno]

Hello together,

the so called inverter charging exists.
It is the electric car Renault ZOE.
The inverter is able to charge with up to 40 kW and uses the motor coils as load inductivity.

This is possible because the engine is a synchronous type with seperate excitation which produces no torque if not excited.
The inverter is normally working with a 400 Volt battery so that the voltage is no problem.

My wife bought that car a month ago and you hear the noise of the motor coils when charing.

[winfried]

A short summary: there are mainly two methods

a) the controller drives coils to get the right charging voltage and current.

b) usage of already build-in regenerative braking circuit for charging.


ad a)
Because a main issue in EV technology there already exists some implementations and patents.
(one I found is from 1990  http://www.google.com/patents/US4920475) and inverter charging in cars at least in the Renault Zoe (thank arno for the hint).

Maybe this solution could be a way for future Zero bikes to use a proper motor controller/charger units, to reduce overall weight and enable fast onboard charging as standard.

I think the strategy, waiting for proper charging stations (with matching charger infrastructure) like sometimes mentioned will not succeed, since for electric vehicles size and weight of charger don't matter and each company wants their own solution and they dominate charging infrastructure development.

ad b)
which I was thinking first of, the controller has to limit current and voltage on the battery side and for the Gen4 Evcon I saw this features in an manual: there are parameter, which can be adjust the maximum battery current for driving and charging separately and have voltage limit, which already should be set correctly.

I assume that during regenerative braking the motor provides voltages higher than the maximum battery voltage for a full charge (116V for zeros) and also a sudden change to strong regen braking could induce high peak voltages from the motor. So they there should be a limiter on input to protect the electronic, but the question still is what is the limit of this ?

Since I don't want to risk my controller to test this, its my only one i will postpone this hack, doing
maybe some voltage recording during a some test rides and concentrate on another solution for an adaptive charging solution for different power sources including fast charging.

Thanks for all the hints...

[Burton]

Winfred the stock setting in the sevcon for regen braking amp limit is not maxed out for the batteries and is about half of what it could be.

Couldn't tell you what voltages come out of the motor during regen but you could measure it.

[kingcharles]

If my memory is correct then the Mission Motorcycle also used this principle for charging.

[Mudface]

anyone tried this since the last post.

had the same idea, start searching and winded up here again

I know the sevcon gen4 size6 can put back at least 4KW during regeneration on the Empulse R.

[dennis-NL]

The highest regen of my 2013 DS I have seen was about -9kW on the Zero app
But maybe it could be higher also because mostly when braking hard I don't watch the app..