Radial Force Characteristics of Switched Reluctance Machine
Abstract
The operation of a switched reluctance machine with eccentric rotor position creates asymmetrical airgap flux distributions and results in unbalanced magnetic pull. This paper comprehensively investigates the static and dynamic radial force characteristics of an 18/12 switched reluctance machine with unbalanced operation. A powerful magnetic equivalent circuit (MEC) modeling approach is developed and allows fast and accurate force predictions with arbitrary excitation and position. The model calculates the instantaneous radial and tangential forces on the individual poles as well as the net forces on the rotor. The method is validated with finite element analysis (FEA) and against experimental results from a 12/8 machine. Static radial force characteristics are first developed. The MEC is the coupled with a time stepping algorithm to calculate the simultaneously varying electrical, mechanical, and magnetic variables for dynamic operation of the complete SR motor drive. Dynamic radial force behavior is examined, where parallel connected windings are found to naturally and significantly reduce the unbalanced magnetic pull. Variations of radial force with torque-speed operating point are also examined.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 17, 1999
- Accession Number
- ADA367752
Entities
People
- Albert Storace
- Charles M. Stephens
- Neil R. Garrigan
- Thomas A. Lipo
- Wen L. Soong
Organizations
- Naval Air Warfare Center