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What he actually seems to do is separately power the field and armature, instead of actually wiring field and armature in series. He uses a secondary controller (a very simple one could do) I think to achieve a field excitation. Interesting reading!
 

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What he actually seems to do is separately power the field and armature, instead of actually wiring field and armature in series. He uses a secondary controller (a very simple one could do) I think to achieve a field excitation. Interesting reading!
Not quite...
When motoring you have an ordinary series setup. When braking, the motoring controller is shut off and another controller with similar current capacity but lower power provides a reverse current to the field. The armature current flows through the diode. Looks good to me.
Gerhard
 

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Not quite...
When motoring you have an ordinary series setup. When braking, the motoring controller is shut off and another controller with similar current capacity but lower power provides a reverse current to the field. The armature current flows through the diode. Looks good to me.
Gerhard
Yes, true. What I was trying to say is that during regen, current does not flow in series trough field and armature.
 

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There are two diodes, VD1 and Noname (lets say VD2).
I was using regen without VD2, and the max.current I could get back into the battery pack was 50-60A at 110V.
When I've installed VD2, the regen current increased. I could get about 80A at 110V instead of 60A while going down the same hill.
I should point out, that brushes of my motor are in neutral position. If you use shifted brush "timing", I can't tell you the result of using regen with "timed" motor. Some say that collector may burn. I didn't test, cause I don't have motor with shifted brushes.
 

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electromobile.ru - this is a pretty clever idea. The only problems I can see with it are the obvious ones: no control over the field current means no control over the armature current (ie - as RPM goes up so will braking effect) and you are probably limited to rather low battery voltages. Still, you have essentially turned a series motor into a PMDC motor without having to resort to contactors, a boost converter (or the double right half plane zeroes that normally plague the series generator).

Have you been collecting data on regen current vs. RPM vs. pack voltage for your particular motor? (if not, you should!)
 

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electromobile.ru - this is a pretty clever idea. The only problems I can see with it are the obvious ones: no control over the field current means no control over the armature current (ie - as RPM goes up so will braking effect) and you are probably limited to rather low battery voltages. Still, you have essentially turned a series motor into a PMDC motor without having to resort to contactors, a boost converter (or the double right half plane zeroes that normally plague the series generator).

Have you been collecting data on regen current vs. RPM vs. pack voltage for your particular motor? (if not, you should!)
Watch the video! http://www.youtube.com/watch?v=FaUp83v0bd8&feature=player_embedded Some small modifications gives control over the field current, and I would rather say the series motor is turned into a sepex during regen. No permanent magnets.
 

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Some small modifications gives control over the field current, and I would rather say the series motor is turned into a sepex during regen. No permanent magnets.
The field voltage is fixed so the field current will remain nominally constant which means the flux is nominally constant... just like a permanent magnet motor. Yes, this is technically turning a series motor into a sepex, but if you hold the field current constant in a sepex motor it will then behave like a PM motor, too.

I suspect something got lost in translation between us because I'm right and so are you ;)
 

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The field voltage is fixed so the field current will remain nominally constant which means the flux is nominally constant... just like a permanent magnet motor. Yes, this is technically turning a series motor into a sepex, but if you hold the field current constant in a sepex motor it will then behave like a PM motor, too.

I suspect something got lost in translation between us because I'm right and so are you ;)

Well, yes according to the drawing, but in the video he is using some kind of heavy duty potentiometer to control field current, that is when it behaves more like a sepex! :)
 

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Guys, guys! Stop your ideas, please.
I use spec.MC that drives HighFreq. 1kW transformer via IGBT transistor. With the help of tiny potentiometer (a red tiny cylinder on gear stick) I regulate the exciting current of the Field. So, whatever motor rpm's, I can regulate regen power with the help of the Field current. You should understand, that series DC motor is reversible device. I mean it can generate power, like SepEx motor. Current and winding counts play the main role here. Lets say, SepEx motor has for ex. has a Field with 200 wire loops and 1Amp. Series motor may have 1 loop and 200 Amper. The magnetic strength of each Field will be the same.
The main idea of my regen device was to eliminate the need to change traction schematic of ordinary pwm-controller&series motor.
 

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Guys, guys! Stop your ideas, please.
You know, there is a chance that our ideas will enhance your device.;) [A lovely solution IMHO.]
My approach to regen has always been to have a pressure sensitive resistor on the brake pedal...increasing pressure = greater regen. When you need greater braking than be provided electrically, the regular brakes come on without any need to think, much greater pressure = mechanical brakes. Any driver can do it without instruction = safety.
Gerhard
 

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Well, at low speed (or motor rpm) regen is imposible with my device. It used when the vehicle speed and as a result the kinetick energy is high enough to get 1-8 kW of energy back into battery. That happens when you running down the hill or decelerating. You would waste that energy into pads' heat, at usual circumstances. And this approach helps to save some % of golden EV energy :) .
I am going to test my device on client's Warp11 direct shaft. Hardly hoping to get reasonable results, but I have to try.
 

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Do you run a neutrally timed motor? If not have you noticed any arcing or excessive brush wear when regening?
Yes, I use neutral timed series motor. I didn't try to shift the brushes timing. It is not necessary on my motor at current voltage level (110V).
 

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HMMM.. I might be interested in this. Did you end up having success with the 11 inch motor? Do you excite the fields with full pack voltage? How much amperage do the fields usually use?
 

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HMMM.. I might be interested in this. Did you end up having success with the 11 inch motor? Do you excite the fields with full pack voltage? How much amperage do the fields usually use?
I am currently on installation process. Workshop guys had broken regen resistor regulator. The problem also is that I am from one region (its like states in USA) and client is from the capital of Ukraine. The process is too slow, but I hope it is going to finish. Tomorow I am going to Kiev, to repeair the broken regulator and to test&film regen by myself. I will report as soon as I can.
Thanks for interest, Inframan. I relied some hopes on this device, but only few guys are interested in it. I don't know why.
 

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Hi Electricmobile

but only few guys are interested in it. I don't know why

I think its because it requires a neutrally timed motor - most of us with DC have advanced timing to cope with increased speed and voltage
 
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