Improved Method for Calculating Magnetic Field of Surface-Mounted Permanent Magnet Machines Accounting for Slots and Eccentric Magnet Pole

Abstract

-This paper presented an improved analytical method for calculating the open-circuit magnetic field in the surface-mounted permanent magnet machines accounting for slots and eccentric magnet pole. Magnetic field produced by radial and parallel permanent magnet is equivalent to that produced by surface current according to equivalent surface-current method of permanent magnet. The model is divided into two types of subdomains. The field solution of each subdomain is obtained by applying the interface and boundary conditions. The magnet field produced by equivalent surface current is superposed according to superposition principle of vector potential. The investigation shows harmonic contents of radial flux density can be reduced a lot by changing eccentric distance of eccentric magnet poles compared with conventional surface-mounted permanent-magnet machines with concentric magnet poles. The FE(finite element) results confirm the validity of the analytical results with the proposed model.

Analytical Average Torque Optimization Method of Parallel Magnetized Surface‐Mounted Permanent‐Magnet Machine with Third‐Order Harmonic Shaping Method

“…The corresponding load torque simulation values can be obtained through finite element simulation of the PM motor. The simulation values are compared with the analytical values obtained using (11), and this comparison is shown in Fig. 4.…”

“…The R&D and application of PM motors started in the 1980s. To date, the PM motors have been widely used in wind turbines, pumps, elevators, air conditioners, electric propulsion system of ships, aerospace, and so on [9][10][11]. These motors can be roughly divided into two types: surface-mounted type and embedded type based on the rotor structure.…”

Analytical Modeling and Pole–Slot Combination Selection Analysis of a Direct-Drive Drilling Permanent Magnet Synchronous Motor

“…The conformal mapping method treats the stator slot depth as infinite when modeling and does not consider the interactions between stator slots, which makes it difficult to calculate the magnetic field and winding inductance of the slots, thus affecting the accuracy of the motor torque calculation [24]. The analytical method is based on the equivalent surface current model and uses a set of surface currents located on the surface of the magnetic poles to simulate the magnetic field of permanent magnets, which eliminates the need for a separate solution for the permanent magnet solution domain, but its solution process is more complicated and it is thus not widely used [25,26]. The subdomain analysis method divides the motor into several subdomains according to different boundaries, materials, and excitations, and the established model is closer to the actual motor, which can accurately predict the magnetic field distribution of the motor [27,28].…”

Yüzey Yerleştirmeli Kalıcı Mıknatıslı Senkron Generatörlerin Tutma Torkunun Azaltılması İçin Stator Yapılandırması

“…Hava aralığı alan yoğunluğunu değerlendirmek için bazı analitik çözüm modelleri geliştirilmiştir. Alt alan modeli [10,[11][12][13][14][15][16][17], bağıl geçirgenlik modeli [11,[18][19][20][21] ve konformal dönüşüm modeli [22][23][24][25][26] hava aralığı manyetik alan hesabında genellikle kullanılan yöntemlerdir. Bu analitik yöntemlerin hepsinde hava aralığındaki manyetik alan, KM'ın alan uyartım kuvvetini temsil eden birinci fonksiyonun bir ürünü olarak hesaplanır [12].…”