8422 Advance Angle Calculation

Ideally, the turn-on angle is advanced such that the reference current level i* is reached just at the onset of pole overlap. In the unaligned position, phase inductance is almost constant, and hence, during turn-on, back-emf can be neglected. Also, assuming that the resistive drop is small, Equation 6.6 can be written as

Now, i=i* and = overlap- on= adv, where overlap is the position where pole overlap begins, the turn-on angle, and adv is the required phase turn-on advance angle. Therefore, we have

The above simple advance angle ^calculation approach is sufficient for most applications, although it does not account for the errors due to neglecting the back-emf and the resistive drop in the calculation.

0 0

Post a comment