proffcharlie

There is a lot of debate about using one ESC to control 2 brushless motors. It seems everybody is setting the motors up in parallel. I was thinking about trying to set them up in series. Not something that would be done with production motors, but wind two stators separated from each other. As an example, start w/ stator 1 pole A. Once the A pole of stator 1 is wound go to stator 2 and wind the A pole of it. After all poles (1A-2A, 1B-2B, 1C-2C etc) are wound then using a wye configuration terminate the end of the windings together at stator 2 and the end of the windings at stator 1 to the ESC. Seems in effect you would have a "twin stator" motor with the stators separated. As I understand the problem most people run into with the motors in parallel, the ESC does not know which timing signal from which motor to use to start up. By doing a series winding such as this there is, or should be, only one position signal per sets of poles for the ESC to reference to.I know the two units would need to be closely matched (magnet and pole spacing, bearing drag etc) but it seems there would be less extremes of tolerances this way.

Has anybody tried this configuration yet? If so how well did it work. Does anybody see a glaring flaw in this idea? I plan to give it a try but if anybody sees a problem I'd like to compare notes before letting the smoke out of the F M box of a perfectly good ESC.

Charlie

Matt Kirsch

My Feedback: (21)

Now that is some original thinking! If anyone else has done it, it's the best-kept secret in town.

Keep us in the loop as to how it's going.

proffcharlie

Well, I'm sad to say the price of knowledge is high. I tried the series winding and all static measurements looked good. However, when power was applied only one motor started. The other motor sat idle until I loaded down the shaft of the running motor. I did not use props so that the system loading would be minimum. When the running motor is loaded it will stop and the other motor starts running. Whichever motor is not running get hot very fast. In testing neither motor burnt out but I believe the ESC was damaged because it will not run any of my other motor properly. The ESC never appeared to overheat, actually it was just slightly warm to the touch. When it is connected to another motor it just stutters as the throttle is advanced. I've tried it on some factory motors as well as some of my home mod units and all respond the same. Well, I guess that's one of the things that make this hobby interesting. As I said, Sometimes the price of knowledge is high!

Charlie