Craftsman Mower Project Part 2: First Ride

This shows the installation of the 2 HP 3600 RPM 3 phase motor connected to the transmission through a V-belt. The motor is driven from 120 VAC through a transformer which supplies power to a VF controller which provides variable frequency three phase power to the motor. There are some problems but I was able to drive it a short distance.

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  Autos & Vehicles

[allanvrc725]

To get 1.5KW with a 150% total for overload makes 2.3Kw, and the kva is close to 3. divide 3000 by 240 = 12.5 amp times 10 for 24 volt = 125 amps plus some loses for the inverter. The whole arrangement will be power hungry unfortunately. I have been trying a few ideas including biasing the windings in relation to each other with some success. This tends to use less current to make magnetism. The idea needs extra inductors and the manufacturer warns that the vfd does not like this.

[allanvrc725]

It would be better with a 4pole motor. I was going to buy a 3phase motor for a car and by reading the specs it showed that torque is much greater as the number of poles increase. An 8 pole motor would be best. But to get any revs the windings or the amount of iron would have to different. Alternatively there would need to be a greater variation in the voltage applied to the motor. A test bench shows how quickly the current climbs with moderate load.