Qunjing Wang

Magnetic field computation of a PM spherical stepper motor using integral equation method

The model of a magnetic field inside the permanent magnet spherical stepper motor is developed using the integral equation method (IEM), and discrete expressions for field distribution are also derived. The results of the IEM and finite-element method show the effectiveness and advantages of IEM for the magnetic field computation on the permanent magnetic spherical stepper motor

Torque modeling and control algorithm of a permanent magnetic spherical motor

A new structure of three degree-of-freedom (3-DOF) spherical motor is presented. The magnetic field of the spherical motor is analyzed by equivalence current method. The torque model of the spherical motor is built according to the interaction of one permanent magnetic (PM) with one electromagnet (EM) derived by Lorentz force method (LFM). The motion singularity is analyzed and the condition number shows that the spherical motor is far away from singularity in workspace. Combined with nonlinear dynamic model and PD control algorithm, simulation of the desired motion is carried out. The simulation results provide reference for motion control research and spherical motor design.

3D magnetic field analysis and torque calculation of a PM spherical motor

The model of magnetic field inside the permanent magnet spherical stepper motor is developed using integral equation method (IEM) and discrete expressions are also derived. The results by IEM and FEM show the effectiveness and advantages of IEM for the magnetic field computation on PM spherical stepper motor. Based on the results of the magnetic field distribution, a torque computation model is developed by using a modified Maxwell stress tensor method. The torque formulation in the case of one phase electrified is given and the torque-angle characteristics arc derived. Comparisons with the results computed by virtual work method demonstrate the effectiveness of Maxwell stress tensor method in the torque computation and analysis of the PM spherical stepper motor

Vision based orientation detection method and control of a spherical motor

The paper presents the orientation detection method of spherical motor based on machine vision to solve the problem about the measurement of the rotor position. A camera is used to capture the image of the rotor painted with special pattern. The position information of the rotor can be derived by analyzing the image. The model of the measurement system is simulated in OpenGL and the measurement errors of the system when rotor rotates around single axis and multi-axis are analyzed in detail. The paper also introduces a new structure of spherical motor. Using nonlinear dynamic model and PD control algorithm, simulation of the desired motion is carried out. The simulation results provide reference for motion control research and spherical design.

Studies on vision based absolute orientation detection method of spherical motor

The paper introduces an absolute orientation detection method for spherical motor based on machine vision. The code generation algorithm, image processing algorithm, image matching algorithm and the method of deriving the orientation of the rotor using unit quaternion are presented. The color pattern painted on the surface of the rotor and camera model are simulated in OpenGL .With the machine vision method and simulation models in OpenGL, the measurement error of the orientation detection system when rotor rotates around single axis and multi-axis and the parameters which influence the resolution of the system are analyzed in detail. Simulation results show the validity of the system and provide references for further research.

Research on the mathematics model and parameter optimization of the claw-pole alternator

This paper presents a novel way about nonlinear regression modeling of the claw-pole alternator oriented to the computer aided design (CAD) with the support vector machines (SVM), which is bused on the severe finite element model (FEM) simulation. Parameter optimization of the claw-pole alternator is also presented, which is based on the genetic algorithm (GA). AS a compared method the chaos used in parameter optimization is synchronously presented

Motion Control Algorithm and Kinematic Analysis of a Spherical Stepper Motor

The structure and operation principle of a PM spherical stepper motor and its gimbal guideway orientation detection system are discussed. According to the arrangement and combination of the permanent magnets and windings, a weighted graph is given which consists of all possible stable positions of the spherical stepper motor. Using the algorithm of the weighted graph, the commuting strategy can be attained and the expected trajectory can be achieved. On the basis of kinematic analysis of the rotor and gimbal guideway, the rigid body kinematic models of single rotor and rotor with the gimbal guideway are derived. Combined with the control strategy, simulations of actual stepping motions and the outputs of orientation detection system in the case of knowing targets points are carried out. Simulation results provide the references for the motion control strategy research and the experimentation design

The simulation and analysis of DC motor driver system for the hybrid electric vehicle

The successful design of the cost-effective electric driver system for the hybrid electric vehicle (HEV) depends chiefly on high efficient PWM converter and advanced control strategy. Based on the visual simulation software MATLAB/SIMULINK, the DC motor and its PWM converter composed of different switch devices were modeled and simulated under various working pattern and switch frequency. The self-tuning modifying algorithm based on fuzzy control was introduced to model the percentage and integral factor of speed controller for the DC motor driver system. Compared with the traditional control algorithm, this method helps to reduce the over-regulating of system, to eliminate oscillation, and to quicken the system respondence as well. In all, the application of the method in the simulation is satisfying.

A Novel Double-Loop Vector Control Strategy for PMSMs Based on Kinetic Energy Feedback

A novel vector control strategy for a permanent magnet synchronous motor (PMSM) based on the kinetic energy stored in the rotor is proposed in this paper. The novel strategy is composed of two closed loops, in which the current loop is the inner loop, and the kinetic energy serves as the outer loop. The theoretical basis and the design procedure of the two loops are given. The feasibility of the proposed control strategy is verified by experimental results. When compared with traditional vector control strategies, the proposed vector control strategy based on energy feedback has better dynamic performance. In addition, an effective estimation solution for the load variation is put forward.

An EKF for PMSM sensorless control based on noise model identification using Ant Colony Algorithm

It is a hot topic that an extended Kalman filter (EKF) is used as speed and position observer in sensorless control of Permanent Magnet Synchronous Motor (PMSM). However, the choice of the EKF covariance matrices is still an unsolved problem as the EKF is applied in sensorless drives. In this paper, the parameters of the covariance matrices are tuned based on Ant Colony Algorithm (ACA). The simulation results show the validity of the procedure.