Investigation of direct flux measurements in switched reluctance motors

Abstract

This paper investigates the use embedded magnetic field sensors in estimating the torque produced by a switched reluctance motor. Recent advances in nanomaterials have enabled the development of very compact magnetic field sensors based on the Giant Magneto Resistive (GMR) effect. This provides a direct measurement of internal magnetic flux levels of an electric machine during operation. With this capability, results are applied analytically to a switched reluctance motor to measure the flux distribution across the surface of a stator tooth. This data is then used in a discrete form of the Maxwell stress tensor to approximate the net torque at the motor shaft. Detailed results are given from a finite element study of a commercially produced switched reluctance motor.

Unbalanced Magnetic Forces in Rotational Unsymmetrical Transverse Flux Machine

“…For position values between the aligned and unaligned positions i.e., overlap position, the flux levels are unsymmetrical, with a slope that varies with rotor position and phase current. This agrees with the investigations of switched reluctance motors in [11]. The flux density components over the grid are plotted as the rotor turns for two pole pitch period in Fig.…”

Accurate model of switched reluctance motor based on indirect measurement method and least square support vector machine

“…direct measurement methods and indirect measurement methods. Direct measurement [5] uses the specific instruments, which are usually too expensive, to measure the flux linkage. Indirect measurement methods [6–12] measure the phase voltage and current first, and then indirectly obtain the flux linkage by calculation based on the circuit equation.…”