Here are some numbers that I've come up with for golf carts. 200-250A for the controller @48V for both series and shunt.
Golf car manufacturers usually specify time limits and torque specs. For example they want a golf car with 2 large men and clubs to be able to be stopped at the bottom of a hill to climb 50 ft up a 22 degree slope. This will require around 350 - 400 lb-ft of torque at the wheels and can see motor and battery current up to 275A. As for thermal considerations the motor will generally give up it's smoke before the controller will in a well designed controller. --- Ashley Roll <[EMAIL PROTECTED]> wrote: > Hi Everyone, > > I've been asked by a client of mine to design an electronic motor > controller > for some low-ish current (30A peak) 36 or 48 volt motors and I got to > thinking that I could probably design it so I can "add more silicon" > and get > it to the stage were it could drive golf carts, it would be a more > useful > product. > > The problem is that I can't seem to find any specifications on what > golf > cart motors consume.. I see that they run on between 36 and 48 volts, > but > I've not seen any current specs. > > Can anyone point me at some reliable information on this? > > I'm looking at a Microprocessor controlled full H-Bridge system with > a > serial interface for programming various parameters like accel and > decel > rates, speed limits, and even be controllable from the serial port. > It would > "normally" be operated by a pot-box. It will support regen and be > able to > limit it so that it doesn't "over charge" the battery pack.. > > Running some numbers on various MOSFETs I would expect I can get a > 100A > continuos rating without too much trouble (and a good heatsink). > Would that > be enough? I'm figuring I can get away with just one 80A MOSFET per > leg for > the 30A version, and go up to 3 or 4 per leg for the high current one > (different MOSFETs, but that isn't a bit problem). > > I haven't done a high current H-bridge before, but I've been doing a > lot of > reading, would anyone familiar with them be interested in critiquing > my > "rough design"? Is there an email list for this kind of thing? > > Thanks for your help guys.. > Cheers, > Ash. > > --- > Ashley Roll > Digital Nemesis Pty Ltd > www.digitalnemesis.com > Mobile: +61 (0)417 705 718 > > __________________________________________________ Do you Yahoo!? New DSL Internet Access from SBC & Yahoo! http://sbc.yahoo.com
