did a bit of digging and found this from knuckles ( i've just cut and past it from my hd I assume the page still exists)
( to john in CR: you said things have advanced quite a bit but how does that relate to this thread?)
Re: Infineon has REGEN BRAKING (and more)
Postby Knuckles on Thu Jan 29, 2009 10:46 pm
solarbbq2003 wrote:thats brilliant on the regen lvc knuckles, I had same problem with v2 controller over 48v, you've solved it! will be extremely useful
Toa Chie for the praise. I just wish China would cater to the products we want (these mods do drive me crazy).
But hacking is fun and very productive.
It is so essential to use both the Software Interface AND a wee bit of hardware mod to get it just the way we want it.
Very cool result about the Infineon regen. I am very pleased. Highly efficient in both directions (I think).
The controller actually becomes an awesome "switching" regulator to provide DC power from a AC BLDC motor.
Heck ... Use a Chinese hub motor as the core of a wind turbine and generate any voltage you want!
(Ha Ha ... hit the throttle and generate a wind storm!)
Or ... Use your ebike as a free-standing exercise-generator that charges batteries (at any V) and/or powers your home appliances! F’n’A
In essence ... Regen is a way to create higher voltages at lower rotor rpm (a BEMF hack). This is very very cool.
(This is how I hacked the upper regen voltage limit)
1) Bike is upside down. No bats at all. LVC is software set to lowest possible LVC value (20.1V). eBrake circuit is closed.
2) Thin red and thick red wires connected together and connected to (+) voltmeter.
3) Thick black ground wire connected to (-) voltmeter.
4) I start spinning the hub motor by hand (like using the wheel spokes as harp strings ... I give it a good fast initial spin).
5) Voltmeter reads BEMF as I spin the wheel (no resistance at all).
6) Once BEMF exceeds LVC value the controller goes into regen mode.
7) Voltmeter value shoots up and I get resistance from wheel (only drawing 60ma to power MCU/pcb "ignition" so resistance is minimal).
'8) I add a little more “plucking” power to the wheel spokes and it starts to slip.
9) I observe that the voltage at the slip point is about 60 V (I am turning the wheel very slowly too).
10) So I figure … “trick” the MCU! F’n’A
11) Did the R12 mod and I can slowly “pluck” spin the hub and generate 85V (+).
12) Bada Bing!
Gosh ... I guess a vid is needed.