Abstract
The electrical and mechanical time constants of a moving-magnet-type linear dc motor (LDM) are required to have small values so as to realize a high-speed response LDM. This paper describes the relationship between the time constant and slot width of a moving-magnet-type LDM. The following results were obtained:
(1) The measured electrical and mechanical time constants were 10.5 ms and 1.6 ms, respectively. The calculated values of the electrical time constant obtained by the permeance method and the FEM were 13.4 ms and 10.2 ms, respectively. The calculated values of the mechanical time constant obtained by the permeance method and the FEM were 1.4 ms and 1.5 ms, respectively.
(2) When the slot width was changed from 3 mm to 8 mm, the electrical time constant decreased by 30.9% and the mechanical time constant became increased by 6.9 %. Changing the slot width improved the response time by 5 ms.
