What do some of the parameters of the Permanent Magnet Synchronous Motor block in Simscape Electronics mean?

1. Stator inductance fluctuation, Lm: What does Amplitude of the fluctuation in self-inductance and mutual inductance of the stator windings with rotor angle mean?

2. Why the mutual inductance is mentioned on the description -> Is the fluctuation of self inductance Ls and the fluctuation of mutual inductance Ms with the rotor angle always the same value?

3. Stator mutual inductance, Ms: Average mutual inductance between the stator windings-> How are these parameters determined? In the documentation the default value is given as 0.00002H which is 1/10 of default value from Ls = 0.0002 H. Should Ms be in this magnitude, so something like Ms = 1/10 * Ls?

4. Stator zero-sequence inductance, L0: Is this the inductance of the stator without having a rotor inside, and is the rotor is expanded for the measurement? In the documentation the default value is given with L0 = 0.00016H which is 85% of default value from Ld = 0.00019 H.

5. For all remaining parameters: How can I determine them?

Answer 1

[MathWorks Support Team]

1. The self-inductance of windings (Laa, Lbb, Lcc) have fluctuation. Ls (which is a constant) is the average self-inductance of each of the stator windings. Please refer to the equation Laa, Lbb, and Lcc on the documentation page for a better understanding of Lm..

2. Lm is the stator inductance fluctuation. The fluctuation of self-inductances (Laa, Lbb, Lcc) of stator windings and the fluctuation of mutual inductances (Lab, Lbc, Lca) between each two stator windings are always the same value (i.e., Lm). Please refer to the equation Laa, Lbb, Lcc, Lab, Lbc, and Lca on the documentation page.

3. Ms comes from the measurement of mutual inductances (Lab, Lbc, Lca) between each two stator windings. There is no strict magnitude relationship like Ms = 1/10*Ls.

4. L0 is the leakage inductance of the stator windings. L0 is always less than Ld and Lq.

5. The derivation of the machine inductances are derived in Chapter 1 (Section 1.5) of the following book.

Krause, P.C., O. Wasynczuk, and S.D. Sudhoff. Analysis of Electric Machinery and Drive Systems. IEEE Press, 2002.

Equations (1.5-25), (1.5-26), (1.5-27), (1.5-29), (1.5-30),(1.5-31) on Page 52 are equivalent to the inductance equations (Laa, Lbb, Lcc, Lab, Lbc, and Lca) shown in the documentation page.