I am trying to design a 5 phase 4 pole motor with five coil. My problem is when I use the basic concordia/park transform to get my id and iq, and finally get Ia,Ib..., the current I get are out of sync with what they should be to properly make the motor turn.
For example, if I set Id = 0, I get Ia = 0 which is good, but Ib and Ic are negative, and Id and Ie are positive. Problem is that when you draw the magnet position, you realise that to get a correct torque, you should have Ib and Id negative, and Ic and Ie negative. In image below, we can see the correct current to properly make the motor turn, which is different compare to what park gives.
I also get problem when I look at back EMF. In a normal three phase motor, the back EMF has three peaks, the phase A, then the B and finally the C. But in 5 phase (with 4 pole) the first peak is A, but the second one is not B. Everything is mixing because of the multiplication of pole, and thus, dq transform is not working.
I am of course considering the electrical angle when it's needed, and i am wondering if I miss-understood something.
If someone could help, I really need to move to dq frame in order to get static torque, torque map, and further efficiency of the motor.
Thanks you
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