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This manuscript introduces a hall-based modified finite position set-phase locked loop (HM-FPS-PLL) method designed for the control system of permanent magnet synchronous motors (PMSMs) in electric vehicles (EVs). The innovative aspect of the presented method lies in utilizing hall sensors pre-installed within the motor and a permanent magnet (PM) flux observer, simultaneously increasing the precision of calculation while reducing computational load. In contrast to traditional sensorless methods employing PLL, this method eliminates the dependency on the PI controller. Both simulations and experimental validations have been conducted to confirm the precision and feasibility of the HM-FPS-PLL method.

This paper investigates the distribution patterns and influencing factors of AC losses in the flat-wire windings of an axial-flux permanent magnet machine (AFPMM) with dual rotor and segmented stators (DRSS). Firstly, several two- and three-dimensional computational models considering eddy current effects are established to balance accuracy and speed. The dimensions of the stator core, including parameters such as slot openings, slot widths, and slot heights, are analyzed and optimized employing the optimal model. Then, the effects of conductor arrangement, wire gauge, stranding, and frequency on AC losses are studied by applying the three proposed configurations for flat-wire windings. A comparison of eddy current distribution and AC losses per turn is presented. Finally, methods for suppressing AC losses in the flat-wire winding of the AFPMM-DRSS are discussed.

This paper proposes an analytical model (AM) for predicting air gap magnetic flux density (MFD) in an axial flux permanent magnet machine with a yokeless and segmented armature under the stator module misalignment fault. The air gap magnetic permeances and MFDs are determined when any stator module is misaligned axially, circumferentially, or radially. Further analysis is conducted on the impact of three misalignment faults on machine performance, including back electromotive force and its harmonics, load torque, and stator core losses. A prototype was manufactured and tested to validate the predictions of the AM and finite element analysis.

This paper proposes a method to create the efficiency map of the Permanent Magnet (PM) assisted Synchronous Reluctance Machine (PMa-synRM). Rather than improve the classic loss models, it is proposed primarily to provide a tool to investigate the mechanism between design parameters and efficiency characteristics. Firstly, an analytic model is built to predict the flux density in airgap and electromagnetic torque. Then the loss distribution is analyzed and the parameters that have a significant impact on the losses are selected to derive loss functions. The output results with corresponding control strategies can be obtained, including the torque, speed and loss. A program to create efficiency map has been established based on the proposed method. The influence of design parameters on the loss and efficiency characteristics is studied using the loss coefficients which obtained by the proposed loss functions. Several criteria are concluded to guide the initial design toward expected efficiency characteristics. The results obtained using the proposed method are compared with Finite Elements Analysis (FEA) results, and experiment platform is also constructed to validate the proposed method.