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24v DC motor controller help

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cdog

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Hello all. I've cobbled together a 30amp bi-directional motor controller which will ultimately be installed in my wife's 8mph Mobility Scooter.
The problems that I have, are a requirement for regenerative braking, and a way of controlling the electro-mechanical brake, which is comprised of a 2amp hold-off coil on a stator-lock attatched to the motor. This must engage when the motor is at actual rest, and must be controlled by the speed/diection control potentiometer. When this solenoid is energised, the motor should be inhibited, but must de-energise when the control potentiometer VR1 is taken from it's centrel null position.
The re-gen braking would need to operate either by or from the H bridge controller HIP4082IP that I have available for this project.

The jpeg below shows my provisional circuit, without the modifications that I've detailed.
The battery voltage (24v) is reduced to 12v by IC3, which supplies IC1, 2, and four.

IC1 forms the PWM signals, frequency determined by R7. The value shown was empirically chosen soley to negate noise.
VR1 is a 10k 52degree travel linear pot arranged centrally in a potential divider function with a dead point, either side of which controlls the PWM duty-cycle, and direction/speed.
These signals are fed to IC2 which cotrols the gate of Q1-4. This device was chosen as an improvement over others of the 4080 family, in that 'shoot-through' at start up is inhibited on-board.

IC4 is configured as a current sensor, or more truly a voltage-difference amplifier, which compares the volages in and out of FS1, and amplifies the drop. This is heavily de-coupled and compared to the adjustable votage from VR2 and at the selected threshold, goes high to the inhibit pin of IC2. Basically, thats as far as I've been able to take it. Any constructive criticism will be warmly welcomed, except to tell me to learn CAD. Rough drawing with a leaky pen I know, but legible still?

Cdog.
 

Sorry Frank and all else. Filesize was too large. Didn't notice. Resized here. cdog
Scooter controller small_resize.jpg (2.55 MB)
 

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