As an integrated control unit that directly transfo rm s digital electric signals into analogy hydraulic signals, High-speed response solenoid valve (HSV) plays an important role in determining an electro-hydrauli c a...As an integrated control unit that directly transfo rm s digital electric signals into analogy hydraulic signals, High-speed response solenoid valve (HSV) plays an important role in determining an electro-hydrauli c automatic system’s overall performance. In the process of designing an HSV, o ne should well understand that various soft magnetic material properties and geo metries greatly affect HSV’s magnetic field design that accordingly has a direc t influence on HSV’s electric performance. As an approach of improving HSV perf ormance, this paper presents an optimal design method on HSV’s magnetic field b y making a full consideration of the effects of various soft magnetic material a nd geometries. The proposed optimal design method, based on HSV’s three-dimens ion solid modeling with the PRO/E software, simplifying from the previous three -dimension solid model to the axially symmetric plane model of the magnetic fie ld and the consequent the magnetic finite element method simulating within ANSYS analysis environment for obtaining accurate results on the distribution of HSV ’s magnetic field and flux-line as well as the magnetic force, can achieve lar ger magnetic force and lower power of an HSV by adjusting the structure paramete rs of the solenoid valve and selecting various soft magnetic materials which are of different B-H (flux density vs. field intensity) curves. Considering the no nlinearity and saturation of various soft magnetic materials, this paper process es the nonlinearity simulated calculation and experiment measure of three soft m agnetic materials and different structure parameters. The comparison of the simu lating and experimenting results proves that the simulating calculation and the proposed optimal design method are effective in HSV’s designing and its perform ance prediction. The researching results show that, for HSV’s designing, the pr oposed optimal design method can well simulate HSV’s the magnetic field, enhanc e the reliability and accuracy, reduce the cost, shorten the cycle, and henc e has practical value for engineering purpose.展开更多
A DC DC buck converter c on trolled by naturally sampled, constant frequency PWM is considered. The existe nce of chaotic solutions and the output performance of the system under differen t circuit parameters are s...A DC DC buck converter c on trolled by naturally sampled, constant frequency PWM is considered. The existe nce of chaotic solutions and the output performance of the system under differen t circuit parameters are studied. The transforming pattern of system behavior fr om steady state to chaotic is discovered by the cascades of period doubling bi furcation and the cascades of periodic orbit in V I phase space. Accordingl y, it is validated that change of values of the circuit parameters may lead DC DC converter to chaotic motion. Performances of the output ripples fro m steady state to chaotic are analyzed in time and frequency domains respective ly. Some important conclusions are helpful for opt imization design of DC DC converter.展开更多
文摘As an integrated control unit that directly transfo rm s digital electric signals into analogy hydraulic signals, High-speed response solenoid valve (HSV) plays an important role in determining an electro-hydrauli c automatic system’s overall performance. In the process of designing an HSV, o ne should well understand that various soft magnetic material properties and geo metries greatly affect HSV’s magnetic field design that accordingly has a direc t influence on HSV’s electric performance. As an approach of improving HSV perf ormance, this paper presents an optimal design method on HSV’s magnetic field b y making a full consideration of the effects of various soft magnetic material a nd geometries. The proposed optimal design method, based on HSV’s three-dimens ion solid modeling with the PRO/E software, simplifying from the previous three -dimension solid model to the axially symmetric plane model of the magnetic fie ld and the consequent the magnetic finite element method simulating within ANSYS analysis environment for obtaining accurate results on the distribution of HSV ’s magnetic field and flux-line as well as the magnetic force, can achieve lar ger magnetic force and lower power of an HSV by adjusting the structure paramete rs of the solenoid valve and selecting various soft magnetic materials which are of different B-H (flux density vs. field intensity) curves. Considering the no nlinearity and saturation of various soft magnetic materials, this paper process es the nonlinearity simulated calculation and experiment measure of three soft m agnetic materials and different structure parameters. The comparison of the simu lating and experimenting results proves that the simulating calculation and the proposed optimal design method are effective in HSV’s designing and its perform ance prediction. The researching results show that, for HSV’s designing, the pr oposed optimal design method can well simulate HSV’s the magnetic field, enhanc e the reliability and accuracy, reduce the cost, shorten the cycle, and henc e has practical value for engineering purpose.
文摘A DC DC buck converter c on trolled by naturally sampled, constant frequency PWM is considered. The existe nce of chaotic solutions and the output performance of the system under differen t circuit parameters are studied. The transforming pattern of system behavior fr om steady state to chaotic is discovered by the cascades of period doubling bi furcation and the cascades of periodic orbit in V I phase space. Accordingl y, it is validated that change of values of the circuit parameters may lead DC DC converter to chaotic motion. Performances of the output ripples fro m steady state to chaotic are analyzed in time and frequency domains respective ly. Some important conclusions are helpful for opt imization design of DC DC converter.
