Abstract: A modeling method for electromagnetic forces and vibration response of a SPM machine, belonging to the field of combined electromagnetic field and structural mechanics computation. First, build the circuit-based EMN model, regular EMN model, and discrete EMN model with equivalent magnetic source and permeance for the different regions of the SPM machine. Second, based on the spatial relationships between each part in the SPM machine, the EMN models of each region are interconnected to form a complete model of the discrete EMN model. The non-sinusoidal high-frequency current harmonics are introduced as input excitation to the discrete EMN model. The global nonlinear matrix equation is solved simultaneously to determine the magnetic flux density in the air gap permeance elements, enabling the air gap electromagnetic force density calculation. Subsequently, the calculated electromagnetic force density is transformed into concentrated forces on the surface of the stator teeth.

Abstract: The present disclosure provides a method for reducing the electromagnetic vibration of a fractional slot concentrated winding (FSCW) permanent magnet (PM) motor, which provides a guidance for the low vibration design of FSCW PM motor. The implementation of the method includes: Based on Nyquist Shannon sampling theorem, the modulation effect of electromagnetic force in the air gap is obtained, and the electromagnetic force component that contributes the most to the electromagnetic vibration of the FSCW PM motor is determined. The equivalent analytical model of PM flux density is established to obtain the phase relationship between different flux density harmonics. According to Maxwell stress equation, the internal relationship between each order of flux density harmonics and electromagnetic force harmonics is obtained. A new magnet structure of the PM motor is designed, and specific flux density harmonics are injected to reduce the electromagnetic force and electromagnetic vibration of the FSCW PM motor.

Abstract: A model predictive decomposition control method and device for an open-winding five-phase permanent magnet synchronous motor is provided. The method includes obtaining the voltage component in the stationary coordinate system under the orientation of the rotor magnetic field, synthesizing the virtual voltage vector that can eliminate the voltage vector in harmonic space according to the vector distribution of the five-phase permanent magnet synchronous motor under the voltage source inverter. The open winding permanent magnet synchronous motor topology is equivalent to the superposition of the independent actions of two inverters. The voltage vector generated by a single inverter is predicted through the mathematical model of the motor. The expected increment is a judgment condition to determine whether the open winding system uses one of the two inverters to maintain the normal operation of the open winding system, or the first inverter is clamped and the second inverter generates the remaining increment.

Abstract: An analysis of a surface mounted permanent magnet (SPM) machine by a 2D meshless method is provided. The 2D meshless method includes steps: discrete nodes are arranged in the region to be solved; based on Taylor expansion and weighted least squares principle, the derivative value of vector potential can be approximated as a linear combination of vector potential values of each node in the support region; partial differential equations are converted into algebraic equations; by solving the algebraic equations, the vector potential of each node can be calculated, and then the distribution of the flux line and the flux density can be obtained. According to the electromagnetic calculation constraints of the machine, parameters such as the back electromotive force and electromagnetic torque of the machine can be obtained.

Abstract: The present disclosure provides a method for reducing the electromagnetic vibration of a fractional slot concentrated winding (FSCW) permanent magnet (PM) motor, which provides a guidance for the low vibration design of FSCW PM motor. The implementation of the method includes: Based on Nyquist Shannon sampling theorem, the modulation effect of electromagnetic force in the air gap is obtained, and the electromagnetic force component that contributes the most to the electromagnetic vibration of the FSCW PM motor is determined. The equivalent analytical model of PM flux density is established to obtain the phase relationship between different flux density harmonics. According to Maxwell stress equation, the internal relationship between each order of flux density harmonics and electromagnetic force harmonics is obtained. A new magnet structure of the PM motor is designed, and specific flux density harmonics are injected to reduce the electromagnetic force and electromagnetic vibration of the FSCW PM motor.

Abstract: The present invention relates to a fault-tolerant modular permanent magnet assisted synchronous reluctance motor (PMaSynRM) and provides a modular winding connection method. The modular winding connection is to change the positions of inlet and outlet coils based on the slot electrical potential star vectogram. Then, each module has a separate set of winding and the left and right relative distribution will be adopted on the winding connection. The invention has the advantages of modularization in structure, high independence between the modules, effectively avoiding overlapping of magnetic lines between the modules, and improving fault tolerance and reliability of the motor. The invention has the advantages of modularization in structure, high independence between the modules, magnetic decoupling between the modules, and improvement of fault tolerance and reliability of the motor.

Abstract: A field modulated doubly salient motor and a design method for a distribution of salient pole teeth thereof are provided. The motor includes a stator and a mover, wherein the stator includes a stator core, two sets of windings, and two sets of permanent magnets. Each of the stator teeth is split into two field winding teeth, and each of the field winding teeth is split into two salient pole teeth. The two sets of windings are respectively armature windings and field windings, wherein the armature windings are wound around stator teeth, and the field windings are wound around adjacent field winding teeth that are split from different stator teeth. The two sets of tangentially magnetized permanent magnets are respectively placed on openings and bottoms of field winding slots, and permanent magnets placed in the same slot or at the same positions of adjacent slots have opposite polarities.

Abstract: A field modulated doubly salient motor and a design method for a distribution of salient pole teeth thereof are provided. The motor includes a stator and a mover, wherein the stator includes a stator core, two sets of windings, and two sets of permanent magnets. Each of the stator teeth is split into two field winding teeth, and each of the field winding teeth is split into two salient pole teeth. The two sets of windings are respectively armature windings and field windings, wherein the armature windings are wound around. stator teeth, and the field windings are wound around adjacent field winding teeth that are split from different stator teeth. The two sets of tangentially magnetized permanent magnets are respectively placed on openings and bottoms of field winding slots, and permanent magnets placed in the same slot or at the same positions of adjacent slots have opposite polarities.

Abstract: A parametric equivalent magnetic network modeling method for multi-objective optimization of permanent magnet motor is provided. Firstly, the disordered region and the regular region of the magnetic flux lines in the motor are divided, and the dynamic mesh model of the disordered region and the magnetic circuit model of the ordered region is constructed. Then, the dynamic mesh model and the magnetic circuit model are connected, and the parametric equivalent magnetic network model of the motor is established. The nonlinear matrix is used to solve the equations, and the magnetic potential of each node is solved to obtain the torque characteristics of the motor. Then, the variable sensitivity analyses of the average torque and torque ripple are carried out by using the parametric equivalent magnetic network model, and the response surface models of the average torque and torque ripple are established by selecting the high sensitivity variables.

Abstract: A parametric equivalent magnetic network modeling method for multi-objective optimization of permanent magnet motor is provided. Firstly, the disordered region and the regular region of the magnetic flux lines in the motor are divided, and the dynamic mesh model of the disordered region and the magnetic circuit model of the ordered region is constructed. Then, the dynamic mesh model and the magnetic circuit model are connected, and the parametric equivalent magnetic network model of the motor is established. The nonlinear matrix is used to solve the equations, and the magnetic potential of each node is solved to obtain the torque characteristics of the motor. Then, the variable sensitivity analyses of the average torque and torque ripple are carried out by using the parametric equivalent magnetic network model, and the response surface models of the average torque and torque ripple are established by selecting the high sensitivity variables.

Abstract: The present invention relates to a fault-tolerant modular permanent magnet assisted synchronous reluctance motor (PMaSynRM) and provides a modular winding connection method. The modular winding connection is to change the positions of inlet and outlet coils based on the slot electrical potential star vectogram. Then, each module has a separate set of winding and the left and right relative distribution will be adopted on the winding connection. The invention has the advantages of modularization in structure, high independence between the modules, effectively avoiding overlapping of magnetic lines between the modules, and improving fault tolerance and reliability of the motor. The invention has the advantages of modularization in structure, high independence between the modules, magnetic decoupling between the modules, and improvement of fault tolerance and reliability of the motor.

Abstract: This invention proposes a method to regulate high efficiency region of permanent magnet motor. The internal relationship between the point with maximum efficiency and the points around it is firstly revealed. Then, the optimal combination of copper loss, iron loss and permanent magnet eddy-current loss is presented when maximum efficiency point moves toward different directions. Hence, the method for regulating high efficiency region can be obtained. This method can be suitable for any type of permanent magnet motors, which can adjust high efficiency region to the dense working point area of the motor under different operating conditions according to design requirements. If this method is used into electric vehicle, it can combine the high efficiency region with the electric vehicle driving cycle to reduce energy consumption and enhance the life mileage of electric vehicle effectively.

Abstract: A permanent magnet brushless motor has a stator, an armature winding, a rotor, and a permanent magnet. The stator is provided with an armature groove. The armature winding is placed in the armature groove. The stator and the rotor are spaced apart by an air gap; the permanent magnet is attached to the surface of the rotor, and is magnetized by a Halbach array structure. The motor is an eight-phase motor, and phases are evenly distributed at a phase belt angle of 45°. The motor and the proposed control algorithm have good fault-tolerant effects, and the average torque after fault tolerance is basically consistent with that in normal operation.

Abstract: An electric motor includes 3 stators and 1 rotor which employs distributed winding. The axial magnetic circuit generates permanent magnet torque, while the radial magnetic circuit generates reluctance torque. By decoupling the axial and radial magnetic circuits, the separation and the independent control of the permanent magnet torque and the reluctance torque are realized. Each stator and rotor can be processed independently, and modular installation can be processed, thereby reducing the difficulty of motor processing.

Abstract: The invention proposes a fault-tolerant field-oriented control method of five-phase interior permanent-magnet fault-tolerant linear motor (IPM-FTLM) with two nonadjacent short-circuit phase faults. Firstly, the extended Clark transformation matrix can be obtained according to the principle that magnetic motive force (MMF) keeps constant before and after the two-phase open-circuit faults, the constraint that the sum of healthy phase currents is zero and the adjacent two-phase current amplitude is equal. The back electric motive force (EMF) can be estimated by the transposed matrix. The nonlinear strong coupling system becomes the first-order inertia system when using the internal mode controller, the first-order inertia feed-forward voltage compensator and back-EMF observer, as the motor is with fault.

Abstract: Disclosed is a double-stator linear vernier permanent magnet (DS-LVPM) motor and method to increase the magnetic field modulation effect. The motor contains a primary, and first and second secondaries on both sides of the primary, spaced by an air gap. The motor secondary includes modulation teeth. The primary is bilaterally symmetrical, and permanent magnets (PM) are embedded in the yoke of the primary core elements. The design solves the inherent problem of flux leakage at the end of PMs for conventional VPM motors, so as to improve utilization of PMs, thereby increasing thrust density of the motors. Additionally, the motor secondaries are laminated by silicon steel sheet, which saves PM material and significantly reduces cost for linear long stroke applications. By adjusting PM structure parameters, the design can use finite element method (FEM) to calculate repeatedly to get PM structure parameters corresponding to maximum electromotive force (EMF).

Abstract: Disclosed are fault-tolerant permanent-magnet vernier cylindrical electric motors with an electromagnetic suspension and a fault-tolerant vector control method for a short circuit of two adjacent phases. The fault-tolerant permanent-magnet vernier cylindrical electric motor with an electromagnetic suspension and the fault-tolerant vector control method for a short circuit of two adjacent phases suppress motor thrust ripples caused by a fault of two adjacent phases of an electric motor. The dynamic performance and the steady-state performance thereof are consistent with those under a normal state, and the switching frequency of a voltage source inverter is constant.

Abstract: A permanent magnet brushless motor has a stator, an armature winding, a rotor, and a permanent magnet. The stator is provided with an armature groove. The armature winding is placed in the armature groove. The stator and the rotor are spaced apart by an air gap; the permanent magnet is attached to the surface of the rotor, and is magnetized by a Halbach array structure. The motor is an eight-phase motor, and phases are evenly distributed at a phase belt angle of 45°. The motor and the proposed control algorithm have good fault-tolerant effects, and the average torque after fault tolerance is basically consistent with that in normal operation.

Abstract: Disclosed are fault-tolerant permanent-magnet vernier cylindrical electric motors with an electromagnetic suspension and a fault-tolerant vector control method for a short circuit of two adjacent phases. The fault-tolerant permanent-magnet vernier cylindrical electric motor with an electromagnetic suspension and the fault-tolerant vector control method for a short circuit of two adjacent phases suppress motor thrust ripples caused by a fault of two adjacent phases of an electric motor. The dynamic performance and the steady-state performance thereof are consistent with those under a normal state, and the switching frequency of a voltage source inverter is constant.

Abstract: The invention proposes a fault-tolerant field-oriented control method of five-phase interior permanent-magnet fault-tolerant linear motor (IPM-FTLM) with two nonadjacent short-circuit phase faults. Firstly, the extended Clark transformation matrix can be obtained according to the principle that magnetic motive force (MMF) keeps constant before and after the two-phase open-circuit faults, the constraint that the sum of healthy phase currents is zero and the adjacent two-phase current amplitude is equal. The back electric motive force (EMF) can be estimated by the transposed matrix. The nonlinear strong coupling system becomes the first-order inertia system when using the internal mode controller, the first-order inertia feed-forward voltage compensator and back-EMF observer, as the motor is with fault.