A discontinuity of magnetic circuits according to the end effect is generated in the permanent magnet linear synchronous motor （PMLSM）. Due to the unbalanced back electro-motive force （EMF） and impedance produced,...A discontinuity of magnetic circuits according to the end effect is generated in the permanent magnet linear synchronous motor （PMLSM）. Due to the unbalanced back electro-motive force （EMF） and impedance produced, unbalanced current is generated. The cireulatin8 current, which is caused by a decrease in the thrust, is generated by the unbalanced current. The optimal design of auxiliary-teeth at the end of the mover was carried out to solve the unbalance of phase by using design of experiment （DOE）, and compared with the basic model through finite element analysis （FEA）. As a result, the auxiliary-teeth model compensates for the decrease of thrust caused by the unbalanced phase. Also, this model is proven to reduce the detent force by the vibration and noise of the PMLSM and copper loss caused by the circulating current.展开更多
The use of design method considering a coil temperature to maximize the thrust density of a double side coreless permanent magnet linear synchronous motor(PMLSM) was presented.The optimal current density where the coi...The use of design method considering a coil temperature to maximize the thrust density of a double side coreless permanent magnet linear synchronous motor(PMLSM) was presented.The optimal current density where the coil temperature reaches an allowable temperature with heat analysis was applied to a magnetic circuit design.Changing optimal current density is verified whenever the design parameters of the motor are altered.The design parameters of the motor were applied to thrust calculation.In this way,the optimal model,which is a reversal of the existing design method,is deduced.The results were compared with the experimental data to verify their validity.When the convection heat transfer coefficient is applied to other models,the results of the analysis and test values show good concordance.The method proposed has some limitations.展开更多
A fuzzy sliding-mode control (FSMC) scheme based on T-S fuzzy models was proposed for the permanent magnet synchronous motor (PMSM) drive system to solve the speed tracking problem. A T-S fuzzy model was firstly forme...A fuzzy sliding-mode control (FSMC) scheme based on T-S fuzzy models was proposed for the permanent magnet synchronous motor (PMSM) drive system to solve the speed tracking problem. A T-S fuzzy model was firstly formed to represent the nonlinear system of PMSM. For converting the tracking control into a stabilization problem, a new control design was proposed to define the internal desired states. Then, the FSMC controller for PMSM system with parameter variation and load disturbance was designed based on the fuzzy model. The performance of the proposed controller was verified by experimental results on PMSM system. The results show that the FSMC scheme can drive the dynamics of PMSM into a designated sliding surface in finite time and guarantee the property of asymptotical stability. The information of upper bound of modeling errors as well as perturbations is not required when using the FSMC controller.展开更多
目的力角特性是永磁直线同步电机(permanent magnet linear synchronous motor,PMLSM)运行稳定性的重要特性,是评价电机性能和控制电机的依据。但在低频工况下,PMLSM的力角特性因电枢电阻的影响而存在偏移现象,进而导致利用现有忽略电...目的力角特性是永磁直线同步电机(permanent magnet linear synchronous motor,PMLSM)运行稳定性的重要特性,是评价电机性能和控制电机的依据。但在低频工况下,PMLSM的力角特性因电枢电阻的影响而存在偏移现象,进而导致利用现有忽略电枢电阻的力角特性分析计算电机低速运行特性会存在较大的偏差。为此,对PMLSM低频低速下的力角特性偏移原因及其影响规律展开深入研究,并确定力角特性偏移的临界条件。方法首先,建立考虑电枢电阻的PMLSM力角特性的解析模型,分析力角特性产生偏移的原因;其次,基于建立的解析模型,通过峰值推力及其对应的功角研究不同因素对推力特性的影响规律,并建立有限元模型对分析结果进行验证。然后,利用解析法确定PMLSM力角特性产生偏移的临界条件,即当力角偏移系数k(k=X_(t)/R_(a))≥11.43可以近似认为峰值推力对应的功角等于90°,可以忽略力角偏移现象;最后,搭建PMLSM样机测试平台,将有限元结果、实验结果与理论分析进行比较,验证推力特性曲线产生偏移的原因和临界条件。结果研究发现,与常用的忽略电枢电阻的力角特性相比,PMLSM力角特性向左偏移。力角特性偏移现象会导致两方面的影响,一是导致推力和电枢电流的关系不单调,出现小负载的电流比大负载的还要大的现象,二是低频运行时峰值推力减小,因此低频时不能保持恒推力运行。结论研究结果对PMLSM的设计和精确控制具有重要的参考价值。展开更多
基金supported by the Second Stage of Brain Korea 21 Projects and Changwon National University in 2009-2010
文摘A discontinuity of magnetic circuits according to the end effect is generated in the permanent magnet linear synchronous motor （PMLSM）. Due to the unbalanced back electro-motive force （EMF） and impedance produced, unbalanced current is generated. The cireulatin8 current, which is caused by a decrease in the thrust, is generated by the unbalanced current. The optimal design of auxiliary-teeth at the end of the mover was carried out to solve the unbalance of phase by using design of experiment （DOE）, and compared with the basic model through finite element analysis （FEA）. As a result, the auxiliary-teeth model compensates for the decrease of thrust caused by the unbalanced phase. Also, this model is proven to reduce the detent force by the vibration and noise of the PMLSM and copper loss caused by the circulating current.
基金Work supported by the Second Stage of Brain Korea 21 ProjectsChangwon National University in 2009-2010
文摘The use of design method considering a coil temperature to maximize the thrust density of a double side coreless permanent magnet linear synchronous motor(PMLSM) was presented.The optimal current density where the coil temperature reaches an allowable temperature with heat analysis was applied to a magnetic circuit design.Changing optimal current density is verified whenever the design parameters of the motor are altered.The design parameters of the motor were applied to thrust calculation.In this way,the optimal model,which is a reversal of the existing design method,is deduced.The results were compared with the experimental data to verify their validity.When the convection heat transfer coefficient is applied to other models,the results of the analysis and test values show good concordance.The method proposed has some limitations.
基金Project (60835004) supported by the National Natural Science Foundation of China
文摘A fuzzy sliding-mode control (FSMC) scheme based on T-S fuzzy models was proposed for the permanent magnet synchronous motor (PMSM) drive system to solve the speed tracking problem. A T-S fuzzy model was firstly formed to represent the nonlinear system of PMSM. For converting the tracking control into a stabilization problem, a new control design was proposed to define the internal desired states. Then, the FSMC controller for PMSM system with parameter variation and load disturbance was designed based on the fuzzy model. The performance of the proposed controller was verified by experimental results on PMSM system. The results show that the FSMC scheme can drive the dynamics of PMSM into a designated sliding surface in finite time and guarantee the property of asymptotical stability. The information of upper bound of modeling errors as well as perturbations is not required when using the FSMC controller.
文摘目的力角特性是永磁直线同步电机(permanent magnet linear synchronous motor,PMLSM)运行稳定性的重要特性,是评价电机性能和控制电机的依据。但在低频工况下,PMLSM的力角特性因电枢电阻的影响而存在偏移现象,进而导致利用现有忽略电枢电阻的力角特性分析计算电机低速运行特性会存在较大的偏差。为此,对PMLSM低频低速下的力角特性偏移原因及其影响规律展开深入研究,并确定力角特性偏移的临界条件。方法首先,建立考虑电枢电阻的PMLSM力角特性的解析模型,分析力角特性产生偏移的原因;其次,基于建立的解析模型,通过峰值推力及其对应的功角研究不同因素对推力特性的影响规律,并建立有限元模型对分析结果进行验证。然后,利用解析法确定PMLSM力角特性产生偏移的临界条件,即当力角偏移系数k(k=X_(t)/R_(a))≥11.43可以近似认为峰值推力对应的功角等于90°,可以忽略力角偏移现象;最后,搭建PMLSM样机测试平台,将有限元结果、实验结果与理论分析进行比较,验证推力特性曲线产生偏移的原因和临界条件。结果研究发现,与常用的忽略电枢电阻的力角特性相比,PMLSM力角特性向左偏移。力角特性偏移现象会导致两方面的影响,一是导致推力和电枢电流的关系不单调,出现小负载的电流比大负载的还要大的现象,二是低频运行时峰值推力减小,因此低频时不能保持恒推力运行。结论研究结果对PMLSM的设计和精确控制具有重要的参考价值。
