Modelling of saturation and cross-saturation effects in an interior PM automotive alternator

Abstract

A rare-earth 6kW interior PM machine has been examined as a concept demonstrator for a high power automotive alternator. This machine has a high magnet fl ux density resulting in strong cross-saturation, and operates with high stator currents resulting in heavy saturation. It is desired to improve the machine design to reduce both saturation effects and hence increase the output power, particularly at low speeds. This paper examines the effect of saturation and cross-saturation on the output power, and uses fi nite-element analysis to model the machine fl ux-linkage curves. The fi nite-element results were verifi ed against the experimental results. "Modelling of saturation and cross-saturation effects.

Multi-objective robust optimization design for powertrain mount system of electric vehicles

“…That is to say, the magnetic field produced by permanent magnet is not sinusoidally distributed in the air gap, but superimposed by the fundamental wave and a series of space harmonic components changing with locations. 17 For example, the magnetic flux produced by permanent magnet in phase A can be expressed as…”

“…That is to say, the magnetic field produced by permanent magnet is not sinusoidally distributed in the air gap, but superimposed by the fundamental wave and a series of space harmonic components changing with locations. 17 For example, the magnetic flux produced by permanent magnet in phase A can be expressed as where Ψ2n-1 is the harmonic flux linkage produced by permanent magnet; n is a positive integer; θ is the included angle between rotor direct axis and stator winding axis (electrical degree). Based on equation (5), Ψd and Ψq can be expressed as …”

“…By substituting equation (7) into equation (1), the nonlinear model of PMSM can be obtained where Ψdn and Ψqn are the harmonic flux linkage of d -axis and q -axis of PMSM, respectively. Then the output torque of PMSM can be expressed as 17 …”

“…What's more, because the inductance of the permanent magnet synchronous motor (PMSM) and flux linkage produced by permanent magnet change with the saturation degree of magnetic circuit, and it also contains a lot of space harmonics in rotor magnetic field, the output torque of the PMSM will be mixed with a certain of fluctuant components. [16][17][18] The rapid and rippled torque transmitted to the body is more likely to lead to longitudinal and vertical vibration of the vehicles. Hence, how to attenuate the vibration caused by the PMSM is an urgent problem and has been paid much attention in recent years.…”

Saturation Effects on the Parameters of Interior Permanent Magnet Synchronous Motors with Different Rotor Configuration

“…Various analytical, numerical and experimental methods have been used for calculating the inductances of PMSM [1,2,3,4,5]. Some of the papers assume constant parameters, independent of the magnetic saturation.…”