Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to re...Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to remedy this deficiency. Firstly, the change speed state （CSS） of the evaluated objects is analyzed based on double inspiriting control lines （DICLs）, and a matrix of the CSS is constructed. Then, 72 elements in the matrix are analyzed, and formulas describing each CSS are given. The efficiency of the proposed evaluation matrix is proved when the CSS merges with the change speed trend （CST） in the dynamic comprehensive evaluation. Finally, a computing example shows that the proposed evaluation matrix is feasible in the dynamic comprehensive evaluation with the speed feature.展开更多
A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yie...A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor.展开更多
In this work, the authors propose the study of a wind speed variable based on the DFAM （double fed asynchronous machine）. The model of the turbine is drawn from the classical equations describing the operation of a ...In this work, the authors propose the study of a wind speed variable based on the DFAM （double fed asynchronous machine）. The model of the turbine is drawn from the classical equations describing the operation of a variable wind speed. The torque generated by the turbine is applied to the DFAM directly connected on the network side and the stator via a bidirectional converter side rotor. This configuration allows velocity variations of ±30% around the synchronous speed and the converter is then sized to one third of the rated power of the machine. The DFAM is controlled by a control vector ensuring operation of the wind turbine power coefficient maximum.展开更多
Two sets of super-synchronization speed control assemblies for two 80 MVA motor-generator units have been developed successfully in order to satisfy the demand of the toroidal field system in the HL-2A tokamak. Based ...Two sets of super-synchronization speed control assemblies for two 80 MVA motor-generator units have been developed successfully in order to satisfy the demand of the toroidal field system in the HL-2A tokamak. Based on the three-phase logical no-circumfluence a.c./a.c. cycloconverter, the speeds of two 2500 kW double fed drive motors have been regulated by means of the vector control technology. The maximum operating speed of each motor- generator unit has been raised from 1488 rpm （revolutions per minute） to 1650 rpm and the released energy of each unit during a pulsed discharge can reach 500 MJ. As a result, the toroidal field system has the capacity to provide 2.8 tesla （T） in HL-2A experiments.展开更多
Single-sided linear induction motors(SLIMs)are widely used as traction components in maglev transportation systems.It is of great practical value to study speed sensorless control methods of SLIM.End-effect which is r...Single-sided linear induction motors(SLIMs)are widely used as traction components in maglev transportation systems.It is of great practical value to study speed sensorless control methods of SLIM.End-effect which is related to the speed of mover is considered,and the M-axis equivalent circuit of SLIM is asymmetric to T-axis.The secondary flux is chosen as the state variable,and the speed identification function is deduced.展开更多
Digital pulsed metal inert gas welding machine with double closed-loop control mode is designed and implemented. It realizes precision control for real time energy and demonstrates the flexibility of digital control. ...Digital pulsed metal inert gas welding machine with double closed-loop control mode is designed and implemented. It realizes precision control for real time energy and demonstrates the flexibility of digital control. Test results of design prototype show that the designed control strategy can effectively adapt to the change of arc length and achieve ideal droplet transfer via one drop per pulse mode. Thus the welding process is stable and the weld bead is good.展开更多
永磁同步直线电机(permanent magnet linear synchronous motors,PMLSMs)因其高速、高精度特性,广泛被应用于高端数控机床,由于其直接驱动负载,易受负载实时变化和外部扰动的影响,因此控制策略的优化至关重要。本文针对PMLSM在数控机床...永磁同步直线电机(permanent magnet linear synchronous motors,PMLSMs)因其高速、高精度特性,广泛被应用于高端数控机床,由于其直接驱动负载,易受负载实时变化和外部扰动的影响,因此控制策略的优化至关重要。本文针对PMLSM在数控机床中的两种典型运动,基于(dSPACE)系统搭建实验平台,分别采用双闭环比例积分微分(proportion integral differential,PID)控制实现高精度位置定位,并引入迭代学习控制(iterative learning control,ILC)结合双闭环PID算法优化往复运动轨迹跟踪性能。实验结果表明,双闭环PID控制的定位精度达到了2μm,实现了微米级定位;ILC+PID算法经历大约40个迭代周期,跟踪误差几乎接近0。本文所提出的控制策略有效提升了PMLSM的运行精度和抗扰动能力,为高端数控机床的精密运动控制提供了可行方案。展开更多
基金supported by the National Natural Science Foundation of China (7127217671302028)+1 种基金the Fundamental Scientific Research Funds for the Central Universities (HEUCF110914)the Heilongjiang Postdoctoral Fund (3236310094)
文摘Methods of the comprehensive evaluation have been studied for many years. However, the change speed of evaluated objects was rarely considered by the existing evaluation methods. An evaluation matrix is proposed to remedy this deficiency. Firstly, the change speed state （CSS） of the evaluated objects is analyzed based on double inspiriting control lines （DICLs）, and a matrix of the CSS is constructed. Then, 72 elements in the matrix are analyzed, and formulas describing each CSS are given. The efficiency of the proposed evaluation matrix is proved when the CSS merges with the change speed trend （CST） in the dynamic comprehensive evaluation. Finally, a computing example shows that the proposed evaluation matrix is feasible in the dynamic comprehensive evaluation with the speed feature.
文摘A new type of brushless DC motor has been developed by using a square wave rare earth permanent magnet synchronous motor with its double loop control circuit. The double loop control scheme of the drive system yields a combination of desired characteristics including simplified control structure, small ripple torque, high speed accuracy, wide operating speed range, and fast dynamic response. Experimental results confirm excellent characteristics of the motor.
文摘In this work, the authors propose the study of a wind speed variable based on the DFAM （double fed asynchronous machine）. The model of the turbine is drawn from the classical equations describing the operation of a variable wind speed. The torque generated by the turbine is applied to the DFAM directly connected on the network side and the stator via a bidirectional converter side rotor. This configuration allows velocity variations of ±30% around the synchronous speed and the converter is then sized to one third of the rated power of the machine. The DFAM is controlled by a control vector ensuring operation of the wind turbine power coefficient maximum.
基金the Tenth-Five-Year Nuclear Energy Development of the Commission of Science and TechnologyNational Defense Industry of the China National Nuclear Corporation
文摘Two sets of super-synchronization speed control assemblies for two 80 MVA motor-generator units have been developed successfully in order to satisfy the demand of the toroidal field system in the HL-2A tokamak. Based on the three-phase logical no-circumfluence a.c./a.c. cycloconverter, the speeds of two 2500 kW double fed drive motors have been regulated by means of the vector control technology. The maximum operating speed of each motor- generator unit has been raised from 1488 rpm （revolutions per minute） to 1650 rpm and the released energy of each unit during a pulsed discharge can reach 500 MJ. As a result, the toroidal field system has the capacity to provide 2.8 tesla （T） in HL-2A experiments.
文摘Single-sided linear induction motors(SLIMs)are widely used as traction components in maglev transportation systems.It is of great practical value to study speed sensorless control methods of SLIM.End-effect which is related to the speed of mover is considered,and the M-axis equivalent circuit of SLIM is asymmetric to T-axis.The secondary flux is chosen as the state variable,and the speed identification function is deduced.
基金Supported by National Natural Science Foundation of China （ Grant No. 50875088）.
文摘Digital pulsed metal inert gas welding machine with double closed-loop control mode is designed and implemented. It realizes precision control for real time energy and demonstrates the flexibility of digital control. Test results of design prototype show that the designed control strategy can effectively adapt to the change of arc length and achieve ideal droplet transfer via one drop per pulse mode. Thus the welding process is stable and the weld bead is good.
文摘永磁同步直线电机(permanent magnet linear synchronous motors,PMLSMs)因其高速、高精度特性,广泛被应用于高端数控机床,由于其直接驱动负载,易受负载实时变化和外部扰动的影响,因此控制策略的优化至关重要。本文针对PMLSM在数控机床中的两种典型运动,基于(dSPACE)系统搭建实验平台,分别采用双闭环比例积分微分(proportion integral differential,PID)控制实现高精度位置定位,并引入迭代学习控制(iterative learning control,ILC)结合双闭环PID算法优化往复运动轨迹跟踪性能。实验结果表明,双闭环PID控制的定位精度达到了2μm,实现了微米级定位;ILC+PID算法经历大约40个迭代周期,跟踪误差几乎接近0。本文所提出的控制策略有效提升了PMLSM的运行精度和抗扰动能力,为高端数控机床的精密运动控制提供了可行方案。
