By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (...By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (D-H) transformation matrix. The error mapping model is derived from original error to the error of the platform by using matrix differential method. This model contains all geometric original errors of the robot. The nonlinear implicit function relation between po- sition and orientation error of the platform and the original geometric errors is simplified as a linear explicit function rela- tion. The results provide a basis for further studying error analysis and error compensation.展开更多
Employing matrix converter (MC) as driving mode, the strategy of model predictive torque control (MPTC) is proposed for three phase permanent magnet synchronous motor (PMSM) system. MC is applied instead of conv...Employing matrix converter (MC) as driving mode, the strategy of model predictive torque control (MPTC) is proposed for three phase permanent magnet synchronous motor (PMSM) system. MC is applied instead of conventional AC DC AC converter to increase the power factor (PF) of the system input side. MPTC is used to select optimal voltage space vector to enable the system to have satisfactory torque and flux control effect. The resultant MPTC strategy not only makes the MC fed PMSM system operate reliably and have perfect control performance, but also makes the PF of the system input side be 1. Compared with direct torque control (DTC), the proposed MPTC strategy guarantees that MC fed PMSM has better command following characteristics in the presence of variation of load torque and tracking reference speed. Simulation results verify the feasibility and effectiveness of the proposed strategy.展开更多
A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4x4 switch matrix with spot size converters (SSCs) and a new driving circuit are designed and fabricated. The introduction of a spot size converter...A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4x4 switch matrix with spot size converters (SSCs) and a new driving circuit are designed and fabricated. The introduction of a spot size converter (SSC) has decreased the insertion loss to less than 10dB and the new driving circuit has improved the response speed to less than l^s.展开更多
基金National Natural Science Foundation of China(No.51275486)the Specialized Research Fund for the Doctoral Program of Higher Education(No.20111420110005)
文摘By selecting any one limb of 3-RSR parallel robot as a research object, the paper establishes a position and orienta- tion relationship matrix between the moving platform and the base by means of Denavit-Hartenberg (D-H) transformation matrix. The error mapping model is derived from original error to the error of the platform by using matrix differential method. This model contains all geometric original errors of the robot. The nonlinear implicit function relation between po- sition and orientation error of the platform and the original geometric errors is simplified as a linear explicit function rela- tion. The results provide a basis for further studying error analysis and error compensation.
基金National Natural Science Foundation of China(No.61463025)Program for Excellent Team of Scientific Research in Lanzhou Jiaotong University(No.201701)
文摘Employing matrix converter (MC) as driving mode, the strategy of model predictive torque control (MPTC) is proposed for three phase permanent magnet synchronous motor (PMSM) system. MC is applied instead of conventional AC DC AC converter to increase the power factor (PF) of the system input side. MPTC is used to select optimal voltage space vector to enable the system to have satisfactory torque and flux control effect. The resultant MPTC strategy not only makes the MC fed PMSM system operate reliably and have perfect control performance, but also makes the PF of the system input side be 1. Compared with direct torque control (DTC), the proposed MPTC strategy guarantees that MC fed PMSM has better command following characteristics in the presence of variation of load torque and tracking reference speed. Simulation results verify the feasibility and effectiveness of the proposed strategy.
基金Supported in part by the National Key Basic Research Special Foundation of China under Grant No. G2000-03-66the Na-tional High Technology Program of China under Grant No.2002AA312060the National Natural Science Foundation ofChina under Grant No. 60336010.
文摘A rearrangeable nonblocking silicon-on-insulator-based thermo-optic 4x4 switch matrix with spot size converters (SSCs) and a new driving circuit are designed and fabricated. The introduction of a spot size converter (SSC) has decreased the insertion loss to less than 10dB and the new driving circuit has improved the response speed to less than l^s.