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Hello all

I have modeled with Comsol 4.2 a stator ring with a ring about 4 inches in diameter with 4 rectangles extending into the center of the ring along the x and y axis representing the four coils of a stator. I selected air for inside and around the ring and steel for the ring and the coil rectangles. I then used AC/DC physics module rotating machinery and declared two multi-turn coil domains, where each one got two opposing "coils" rectangles with 560 turns and a current of Imax*exp(-i*phase1) and Imax*exp(-i*phase2) where Imax is 10 amps * sqrt(2) and phase 1 is 0 degrees and phase two is 90 degrees, pi/2. I then added a prescribed rotational velocity and selected the ring and the four coil rectangles for the domains and 15 rps. I then meshed the geometry and tried to solve a time dependent study but it threw up an error saying failed to find consistent initial values. However, when I make the current for the coil rectangles as just Imax, or 10 amps, the study solves just fine.

What can I do to make the solver solve when I have the currents as Imax*exp(-i*phase1) and Imax*exp(-i*phase2)????

Thanks so much for the help.
Stephen