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Linking four(maybe8)24v DC Motors to work together...also possibly a 72v motor as well for a small EV...is it feasible?? Answered

Is it possible to connect four,or more(maybe8-even possibly 16!!!is that crazy???) 24 volt dc motors together to run a small ev?The motors were used originally to drive hydraulics on tail lifts at 145bar pressure.Also i have a small 72volt motor as well....can all these motors be linked and run together.To get there'power' to the wheels is a different bridge to be crossed at a different time(so says I optimistically...LOL)!But basically can it be done and how?Is it even feasible?.I will be using the same controller I intend to use for a 48v 120amp DC motor in another EV-the controller runs at 144v and 500amps,but will be enquiring about doubling this.The 24v motors are guestimated to be about 12" in circumference and about 11-12"high(possibly slightly smaller by inch or so).I am not an electrical engineer but am mechanically minded.I also have had a lifelong fear of electricity since being blasted with 240v when i was 6yrs old!!SO PLEASE BE GENTLE!!I know that there are more then enough intelligent and knowledgeable people out there who can maybe help me with this problem which is why I chose to use this forum/site.I really really need your help people.I would be very very grateful for a loan of your knowledge and kindness for doing so.Many many many thanks for your time,your help and most importantly your patience....its very deeply appreciated.Again many thanks.Warren


since they're probably small motors, you could use them to independently drive each wheel on the ev...each motor needs an individual motor driver.

Thats my thinking for the little 24volt motors...to run each wheel off each motor!4 wheels=4 motors=96volts.I will find out more specs to do with the motors,such as the watts and amps.At the moment all i know is there 24 volt!However,where your losing me is with the controller(s)!I thought that each motor would need the same amount of power running to it (so they would all be running "in synch"),therefore giving each motor the power they need(equally)-could i not just run the motors from the 144volt 500amp controller-as there only drawing a total of 96volts,(leaving a surplus of 48 volts).And then run a potentiator for them from the controller.I always thought that dc motors could be ramped up a little with there voltage as well.Or am i way off with my thinking???knowing me...probably!Anyhow,if each motor needs its own separate controller,do you or has anyone on here have plans to make the controllers using pcb,power board,mosfets etc and could i ramp up the voltage????thanks

See attached.

Batteries are any configuration of 24v batteries you can reasonably charge.

Note, Motor controller and drivers may be on the same physical board - just broken out here logically.

The controller takes intructions from the gas and brake pedals to decide how to go. They generate INSTRUCTIONS for the motor drivers to follow. this may be data that gets interpreted by another computer in the driver, or more commonly, is just a pulse-width modulation (pwm) signal sent to the driver.

The drivers are basically really heavy duty electronic switches. They take the pwm signal (very low power) and use that signal to turn the motors on and off (or control their speed with pwm).

Fundamentally the controller would also be hooked to the battery so that its internal computer would run.
Also, this is the most complex design you could implement. Realistically this can drive each wheel independently at a different speed - but its more likely it only generates one output signal (since all wheels travel the same direction) -- then drive all the wheel drivers with the SAME signal so they all go the same.

Specifics: You'll have to search for motor controllers and drivers.

motor controller.PNG

Thanks for your answer Frollard.Maybe i was reaching a bit high by thinking of linking so many motors up,but im still keen and still very much in the dark.I'm aware of PWM and controllers and motor drivers...not intricately,but i know there are two parts to a controller-the low voltage pcb with software,im assuming flashed onto an eprom or something(yes...no??)that 'tells'...."something" what to do...go back,go forward or stop(y...n??)that "something"is the high power part of the controller that deals with the actual flow of 'power' into the motors(yes...no??)...that has all the MOSFETS etc on it...the power board??Sorry,but im still confused!I know if you run batteries in series,say 3x 12 volt bat with 120Ah, the voltage will be 36 volts still at 120 Ah...likewise if run in parallel the voltage would be 12volts and the Ah would be 360Ah...so if a 24volt series dc motor was run through a 72 volt 200amp controller(is that otherwise called a h bridge??IDK??)it runs at whatever voltage gets sent to it by the controller thru the way it is constructed,assisted by the potentiometer(sorry 4 the bad spelling)then WHY cant 2 motors be run from the one controller as long as there 'call' for voltage didnt exceed 72 volts?why isnt the output from the controller 'split'equally between the 2 motors....sending out 72volts,then they both get 36 volts,assuming i pressed the pot right down???so assuming i ran the motors in parallel they would both receive 36volts...(y...n???)so therefore couldnt i run them in a parallel/series configuration.i vaguely remember reading something about a guy who runs an EV car using 2 dc motors called the "white zombie"....and also vaguely remember reading that the software was switching the power from series to parallel every 300 miliseconds or something!!How is this possible...is it all software controlled!Am i correct there??...can i run 2 dc motors together??.I only pretty much understand things in very simple laymans terms,using analagies to explain things as im not a electrical engineering student or a physics graduate...just a simple bloke from a simple town in england!just need to understand this as i hate waste,love the environment and what else would i use these motors for if not for a small sized EV.Im currently welding a chassis,the double A wishbone suspension etc etc,and have a much larger series wound DC motor that will be run from a controller with deep cycle batts all conventionally configured,that is to say run,singularly as per the norm for EV's-all from scratch.Is it in the software....is it in the way the 2 motors are 'wired up'????I just need enlightening as to this problem and where my thinkings going wrong!!Im not shy or ashamed to admit that i havent got a clue about a thing....and i havent...LOL!Maybe u could help light up my mind with your sparks of knowledge.( - : Thanks if you or anyone else can and would help me solve this problem.

no... each off its OWN driver, which is at best in parallel. You need to read up on how a motor driver would work - and drive each motor separately. series only causes problems when you add up motors like this, since ideally they all have their own control.


7 years ago

you must make the controller. idk how to do it but frollard seems to know more