Shape and topology optimization of a permanent-magnet machine under uncertainties

Journal of Mathematics in Industry

Table 2 Values of some physical parameters of the ECPSM model before and after optimization

Quantity (unit)	Before optimization	After optimization	Decrease/increase
Expectation of the cogging torque (Nm)
Rectified mean value	0.072	0.012	83.70%↓
RMS value	0.085	0.015	82.19%↓
Minimal value	−0.139	−0.027	80.21%↓
Maximal value	0.138	0.026	80.51%↓
Mean value of standard deviation	0.004	0.002	43.19%↓
Expectation of the back EMF (V)
Rectified mean value	257.1	225.9	12.14%↓
RMS value	268.3	240.6	10.33%↓
Minimal value	−330.0	−299.8	9.14%↓
Maximal value	330.0	299.8	9.14%↓
Mean value of standard deviation	6.34	6.23	1.85%↓
Expectation of the air-gap magnetic flux density (T)
Rectified mean value	0.575	0.471	18.08%↓
RMS value	0.592	0.502	15.11%↓
Minimal value	−0.647	−0.539	16.73%↓
Maximal value	0.733	0.749	2.29%↑
Mean value of standard deviation	0.019	0.017	12.29%↓
Expectation of the electromagnetic torque (Nm)
Rectified mean value	2.407	2.014	16.31%↓
RMS value	2.433	2.019	17.02%↓
Minimal value	1.738	1.779	2.31%↑
Maximal value	2.788	2.200	21.11%↓
Mean value of standard deviation	0.09	0.063	20.33%↓
Expectation of others quantities
Ripple torque (%)	43.62	20.90	52.10%↓
THD of the back EMF (V/V)	0.732	0.498	31.93%↓
Mass of iron pole (g)	15.95	14.94	6.32%↓
Mass of PM pole (g)	15.95	12.19	23.56%↓