Calculating Motor Size

First, determine how fast you need it to accelerate, then apply this formula

Time to accelerate an electric motor

Once you get an idea of the necessary torque you need from that, and the speed you want to travel, you can start messing with motor sizes and gear box ratios.

Hi Garry,this project sounds like Columbus stainless steel...If so why not ask Tim Green if he still works there.Andre also wanted to use a hydrastatic drive system that was self container with a power pack mounted in the coil car body athe same as the square coil carriers.I would be very interested in the end result.

Best

Robert Ferreiro

To Flegelo

Not Columbus steel, Macsteel they mounted a .55Kw motor with a 25rpm gearbox,chain driven with a sproket ratio of 30 tooth on the gearbox side and 19 tooth on the wheels.The motor is mounted in the centre of the coil car and fed by means of a reel drum,now they want to add a another 0.5 Kw motor to drive the other set of wheels with a VSD dive.I have calculated that the minimum size of the motor should be about a 7,5Kw if you work that 1hp to move 0,3kg!

To garryvg,If i remember correctly they wanted to mount a 30Kw motor and 32 rpm grearbox and a chain drive but I think the motor and gear box were stock items so no buy outs.The hydrostatic drive option was because they did not like the drum of cable going to a frow.I do remember the 1Kw to .1kg a bit of over design..they looked at it as rather too much power than too little.I stopped going there so what they did I could not tell you.I ws asked about the hydrostatic drive system which the saftey guys liked more than the cable.

Miss home cold at this time I am told?

many thanks

Hi: in a steady mode you have

Power= Force x speed

You have the speed, but you will have to estimate the force. You can estimate the friction coefficient, that will depend of the kind of wheels, diameters, soil, etc.

Another question is the adoption of what kind of motor, electrical, hidraulics?

The car has electrical supply be mens of a trolley? or will have batteries?

At the begining of a design, more advance implies more questions...

regards

d*d*l=(kW/cN)

where,

d=daimeter of rotor

l=length of rotor

c=constant=1.64e-4*b*q

N=speed

b=magnetic loading

q=electrical loading