数控直线电机进给定位误差补偿技术研究

介绍了应用双频激光干涉仪测试数控直线电机进给的定位误差方法,并利用最小二乘法分别建立定位误差的线性模型、分段线性模型、样条拟合模型,并对数控直线电机进给的定位误差进行补偿。研究结果表明,采用软件补偿的方法可以较大地提高直线电机进给的定位精度。

永磁电机数控装配机的设计研发

对于中、大规格的永磁电机,由于永磁体的磁力作用,将转子组件与定子组件装配在一起的总装工序极其困难,因此要设计一种永磁电机定子、转子数控装配机。通过对某公司生产的GK813系列电机进行永磁电机数控装配机的整机结构设计,把装配机分为多个模块进行具体的设计,再按照永磁电机数控装配机的工装步骤进行数控设计,得出装配时定子与转子的静不平衡吸力的分析结果,经实践验证该设计采用柔性装配,可提高永磁电机装配质量。

基于PSoC平台的数模结合实验项目设计

数模结合的综合性实验可以促进学生对电路知识的融会贯通,培养学生的综合实践能力,但实验的复杂度和难度也相应有所增加。基于PSoC平台的实验箱包含多样的数字及模拟功能模块,为数模结合实验提供了很好的平台,提升了实验的多样性和趣味性,降低了实验的难度,使得更多学生能完成该类实验。该文提出了基于PSoC平台的数模综合性实验设计原则,介绍了两类基本的综合实验框架在实验教学中的应用,并以学生完成度较好的数控小电机为实例阐述了学生实现过程。

New Method to Restrain Pumping Voltage of Braking Procedure for Brushless DC Motor of Electric Armored Vehicle

In order to restrain the high pumping voltage of braking procedure which is harmful to the system of electric armored vehicle. Based on the analysis of pumping voltage of the braking procedure, the relation between pumping voltage and PWM ratio is derived and a new digital control method to restrain the pumping voltage by changing PWM ratio is put forward. Because the capacitance is decreased effectively, the volume of controller is reduced and the performance to price ratio is improved. The results of computer simulation and experiment proved that this method is feasible and valid.

高精度双向同步旋转CORDIC算法设计与实现

针对精密电机数控领域中16位位宽的坐标旋转数字计算机(coordinate rotation digital computer,CORDTC)算法存在输出时延长、运算精度低、稳定性差等问题,提出高精度双向同步旋转CORDIC算法,通过角度预处理和区间折叠扩大收敛区间,迭代过程中采用双向同步旋转与误差均衡来提升算法的精度以及健壮性,最后根据区间结果进行还原输出.结果表明:在硬件实现上,相比传统算法,本算法的运算精度分别提高了76.3%,最大输出时延降低了71.4%,具有高精度、低延时以及稳定等优点.

Numerical Controlled Two Optical Paths CO_2 Laser Die-Cutting Technology

A CO2 laser die-cutting system, which does not need die board any more, is a new technique for manufac-turing packing box. Two optical paths, the galvanometer scanning system and the flying optical system, are used to satisfy different processing needs. The scanning system is composed of galvanometer scanning mirrors and F-θ lens. And the flying optical system is driven by two servo motors. This paper presents the software and hardware design of the laser die-cutting system, the difference between the two optical paths, as well as the relationship among the cutting speed, thickness of wrapping paper and laser power. The cutting speed and thickness of wrapping paper are linearly increased by the incremental laser power, while the cutting speed is hyperbolically decreased by the incremental thickness of wrapping paper when the laser power is constant. The amount of incision is reduced by 20% and the processing time by 40% when tested by a low power RF CO2 laser die-cutting system using the optimized program. This tech- nique is also used for the reference of other rapid laser processing systems.

Researches On The Design And Application Of DSP Multi- motor Collaborative Control System

As an important branch in the field of servo control, multi-motor coordination motion control applications are increasingly widespread.For open CNC system requirement, taking DSP as master core, combing with specific integrated stepper motor driver chip LMDI8201T, this designed a serial communication-based new collaborative multi-motor control system, which has characters of highly integrated, good stability, real-time, convenient man-machine interface.The test results show that the system fully meet performance requirements and achieved the motion control functions.

Influence of Pre-injection Control Parameters on Main-injection Fuel Quantity for an Electronically Controlled Double-valve Fuel Injection System of Diesel Engine

A simulation model of an electronically controlled two solenoid valve fuel injection system for a diesel engine is established in the AMESim environment.The accuracy of the model is validated through comparison with experimental data.The influence of pre-injection control parameters on main-injection quantity under different control modes is analyzed.In the spill control valve mode,main-injection fuel quantity decreases gradually and then reaches a stable level because of the increase in multi-injection dwell time.In the needle control valve mode,main-injection fuel quantity increases with rising multi-injection dwell time;this effect becomes more obvious at high-speed revolutions and large main-injection pulse widths.Pre-injection pulse width has no obvious influence on main-injection quantity under the two control modes;the variation in main-injection quantity is in the range of 1 mm3.

Thermal Error Compensation for Telescopic Spindle of CNC Machine Tool Based on SIEMENS 840D System

In this paper, eddy current sensors and thermocouple sensors were employed to measure the thermal field and thermal deformation of a spindle of a telescopic CNC boring-milling machine tool, respectively. A linear regression method was proposed to establish the thermal error model. Furthermore, two compensation methods were implemented based on the SIEMENS 840D system by using the feed shaft of z direction and telescopic spindle respectively. Experimental results showed that the thermal error could be reduced by 73.79% when using the second compensation method, and the thermal error could be eliminated by using the two compensation methods effectively.

A novel current vector decomposition controller design for six-phase permanent magnet synchronous motor

The vector control algorithm based on vector space decomposition （VSD） transformation method has a more flexible control freedom, which can control the fundamental and harmonic subspace separately. To this end, a current vector decoupling control algorithm for six-phase permanent magnet synchronous motor （PMSM） is designed. Using the proposed synchronous rotating coordinate transformation matrix, the fundamental and harmonic components in d-q subspace are changed into direct current （DC） component, only using the traditional proportional integral （PI） controller can meet the non-static difference adjustment, and the controller parameter design method is given by employing intemal model principle. In addition, in order to remove the 5th and 7th harmonic components of stator current, the current PI controller parallel with resonant controller is employed in x-y subspace to realize the specific harmonic component compensation. Simulation results verify the effectiveness of current decoupling vector controller.

Research on Intelligent Positioning Bed of Body Gamma Knife Based on Sensor

This paper introduces a design to improve the radiotherapy accuracy of gamma knife. In this design, sensor is used to collect respiratory parameters and tumor displacement (caused by human respiration) model is established through optimization modeling. At the same time, data are transferred to single chip microcomputer (SCM) system by pressure sensor and then stepping motor is controlled by SCM. Finally, the intelligent positioning bed is under the control of stepping motor. As a result, the intelligent positioning bed can move reverse to respiratory law. The experimental results showed that this method can reduce the influence of respiration on tumor displacement, improving the accuracy of intelligent positioning bed with simple circuit and low cost at the same time.

Design of digital control DC voltage source based on AT89C52 MCU

the system to DC voltage source as the core, AT89C52 MCU as the main controller, the output voltage to set the DC power supply through the keyboard, with a step function voltage to reality, the actual output value. This design is divided into four modules： SCM control and display module, digital to analog （D/A） conversion module, a constant voltage source module, output module. MCU control module as the core, the input signal is converted to digital quantity output; constant current source module voltage D/A conversion to analog conversion into constant pressure through a constant voltage circuit. The system has good reliability, high precision.

Performance Analysis of PMSM Equations Computation

The paper deals with the comparison of three different digital devices used for the computing of permanent magnet synchronous motor （PMSM） model. Model is used for virtual high frequency injection method （VHFIM） sensorless control, where injection and acting voltages are virtual ones. For computing the whole PMSM model, differential equations are used. The paper is focused on performance analysis of computing speed and accuracy of field-programmable gate array （FPGA） device, digital signal controller and Power PC microcontroller and results are compared.

Distinguishability analysis of controller parameters with applications to DFIG based wind turbine

The power system controllers normally have more than one parameter.The distinguishability analysis of the controller parameters is to identify whether the optimal set of the parameters of the controllers is unique.It is difficult to obtain the analytic relationship between the objective of the optimization and the controller parameters,which means that the analytical method is not suitable for the distinguishability analysis.Therefore,a trajectory sensitivity based numerical method for the distinguishability analysis of the controller parameters is proposed in this paper.The relationship between the distinguishability and the sensitivities of the parameters is built.The magnitudes of the sensitivities are used to identify the key parameters,while the phase angles of the sensitivities are used to analyze the distinguishability of the key parameters.The distinguishability of the controller parameters of wind turbine with DFIG is studied using the proposed method,and dynamic simulations are performed to verify the results of the distinguishability analysis.