Analytical Modeling of Surface-Mounted and Consequent-Pole Linear Vernier Hybrid Machines

Abstract

This paper presents an analytical method for modelling the no-load air gap flux density of a surface-mounted and a consequent-pole linear Vernier hybrid machine (LVHM). The approach is based on simple magneto-motive force (MMF) and permeance functions to account for the doubly-slotted air gap of the LVHM. These models are used to determine the flux linkage, induced electromotive force (EMF) and average thrust force of each machine. The accuracy of the two analytical models is validated by comparison with 2D finite element method (FEM) solutions. Based on the analytical models, it is found that the working harmonics of both surface-mounted and consequent-pole LVHMs are essentially the same. However, the magnitudes of these working harmonics in the consequent-pole LVHM are invariably greater than those of surface-mounted LVHM. Further, using the analytical model, the contribution to the thrust force of the machine by each individual working harmonic can be shown clearly, and is used to explain why the consequent-pole LVHM has improved performance despite using only 50% of the permanent magnet (PM) material compared to the surface-mounted LVHM.

Linear Permanent Magnet Vernier Generators for Wave Energy Applications: Analysis, Challenges, and Opportunities

“…The analytical analysis of a linear vernier machine was realized in [70] based on flux harmonic theory. In addition, two structures of surface-mounted and consequent-pole LPMVMs were analytically surveyed in [71]. Although the proposed procedure can be accomplished in a short time, the analysis did not consider the magnetic saturation and longitudinal end effect.…”

Two-dimensional analytical model for five-phase fault-tolerant permanent-magnet vernier machines

“…An analytical model has been presented for a surface-mounted and a consequent-pole linear vernier hybrid machine by modeling the no-load air-gap flux density to compute the flux linkage, induced EMF and average thrust force of each machine (Botha et al, 2021) The proposed machine combines the merits of vernier and fault-tolerant machines to achieve higher reliability and higher torque at low speed. Increasing the number of phases leads to reduce the torque ripple as well as the current of each phase for a predefined nominal voltage.…”

“…Wang et al (2021) have implemented the non-linear analytical solution to calculate quantities of magnetic field and performances on a spoke array vernier PM machine based on the sub-domain technique. An analytical model has been presented for a surface-mounted and a consequent-pole linear vernier hybrid machine by modeling the no-load air-gap flux density to compute the flux linkage, induced EMF and average thrust force of each machine (Botha et al , 2021). Oner et al (2016) have used the analytical model to calculate the cogging torque, magnet losses and efficiency of PMVMs.…”

Research on Segmented Primary Consequent-Pole Permanent Magnet Linear Synchronous Motor with Symmetric and Periodic End Force

“…IP and PM are alternately arranged for excitation. This structure has been applied to both rotary motor [2][3][4][5][6][7][8][9][10][11][12][13] and linear motor [14][15][16][17][18][19][20].…”

“…In [14], the proposed topology of double-sided shifting one pole pitch can offset magnetic unbalance, which is beneficial to suppress the thrust ripple. In [15], in order to get the flux linkage, induced EMF and average thrust, the surface-mounted and CP linear vernier hybrid motor shows an analytical method which can model the no-load air-gap flux density. In [16], the leakage flux could be suppressed by the novel dual-CP transverse flux linear topology.…”