Double stator linear and rotary permanent magnet (DSLRPM) machine is a novel two-degree of freedom (2-DOF) linear and rotary machine, which incorporates the merits of the rotary and linear permanent magnet machine to realize linear and/or rotary movement. It features the simple and compact structure, high mechanical integration, small volume, high power density, high positioning accuracy, easy to process and manufacture. Those make it suitable for the automatic shifting transmission gear box, multi-coordinate machining center, mechanical arm etc.. In this dissertation, the keys of the theoretical and technical issues about DSLRPM machine are deeply and systematically investigated, including the electromagnetic design, electromagnetic characteristics, structure optimization, analytical analysis of the electromagnetic field, analytical analysis of the electromagnetic thrust and torque, mathematical modeling, and the control strategies and experiment platform of the DSLRPM machine. Both the simulant and experimental results are given to verify the theoretical analysis. This work lays an important foundation for the further research and application of the DSLRPM machine in robot, processing machine tools and other industrial application area.
The major research works of this dissertation are as follows:
1. The structure characteristics, electric and power generation operation principle of the DSLRPM machine are analyzed in detail. The power-size equation of the DSLRPM machine is deduced, as well as the equation of the relationship among the magneto motive forces generated by the excitation current and permanent magnets and electromagnetic thrust and torque, which lay theoretical base for the design of the HAFFSPM machine. Moreover the initial design parameters are proposed based on the power equation.
2. Based on the 3-D finite element (FE) method, the electromagnetic and load characteristics of the six phase 9 slots / 8 poles and 12 slots / 10 poles DSLRPM machine are studied, including the field distributions, air-gap flux density, flux linkage at no-load, back EMF, winding inductance, cogging torque and detent force, output torque and thrust, and output power etc.. The FE analysis results are compared with that of the theoretical analysis, which verifies the correctness of the design theory of the DSLRPM machine.
3. The influence of the orthogonal magnetic field (OMF) and the end effects is analyzed. In regard to the structure of the long mover structure and short stators, the influences of the end effects on the static and dynamic characteristics of the DSLRPM machine is studied, and the optimized end structure is given. In consideration of the OMF in the DSLRPM machine, the characteristics of the iron core in the OMF is analyzed base on the FE method, and the experiment are done. The experiment results verify the effectiveness and correctness of the FE analysis. Based on the analysis results, the two degree finite element method is used to analyze DSLRPM machine, and the thickness of the mover and PM are optimized. The analysis results lay the important theoretical foundation for DSLRPM machine space utilization and power density improvement.
4. In the Cartesian coordinate, the analytical method of the DSLRPM machines with considering the OMF effects are proposed by solving the Maxwell’s equation, conformal transformation and equivalent magnetic circuit equation. The electromagnetic characteristics, including the airgap flux density, cogging torque, detent force, electromagnetic torque and force are analyzed. In overall consideration of the back-EMF and the cogging torque, the rotor structure parameters and the topology representation variable of the three structures are optimized. The analytical analysis results are compared with that obtained by the FE analysis, which verifies the accuracy and validity of the analytical model.
5. The mathematical models of the DSLRPM machine are built and analyzed both in stator and rotor reference frames. The vector control strategy is studied and the simulation model of the DSLRPM machine under vector-control is built based on MATLAB/Simulink. The correctness of the mathematical models and the control strategy are proved by the results of the simulation.
6. The hardware of the control system of the DSLRPM machine, including the main power circuit, control circuit, detection circuit, protection circuit, and driven circuit, are designed. The control software of the electric and power generation operation is also designed based on the hardware system. Those lay the hardware and software foundation for the testing and building the operating system of the DSLRPM machine.
7. The experimental platforms, including electric and power generation operating testing platform, of the DSLRPM machine are established. The experimental research about the electromagnetic characteristics, the DSLRPM machine under vector-control, and power generation operating characteristics are done, which validates the design of the DSLRPM machine and the control strategies and lays foundations for the further investigation and industry application of the DSLRPM machine.