大型机电驱动系统的优化——现代电子数据处理方法的能力和限制

大功率特殊电驱动大多数受到技术可行性的限制,它要求持续采用先进的、柔性的计算方法.这种驱动系统的优化前提是在考虑了所实施的设备系统间的各种相互作用后,对过程作出全面的、专业性的评估.讨论在计划和设计大型定制电气驱动时,合理应用高效的电子数据处理方法所面临的机遇和风险.

基于MATLAB的采煤机驱动系统速度调节特性研究

由于采煤机截割滚筒在进行调速时会导致传动不稳、抖动等情况,因此,利用MATLAB仿真分析软件建立了采煤机驱动机构的耦合动力学模型,对其驱动系统的速度调节特性进行研究,针对性地制定了提升采煤机综采作业效率的方案。结果表明:当截割阻力大时采用联合调速方案能够在确保工作安全性的前提下最大程度提升综采作业效率,当截割阻力较小时采用截割滚筒调速的方案能够确保在工作安全性的前提下最大程度提升煤井下的综采作业效率。

RF MEMS switches based on thermal actuator

A new switching circuit is presented for the application in the frequency range of 0 to 8 GHz. This switch is electro-thermally actuated and exhibits high radio frequency （RF） performance due to its lateral contact mechanism, It composes of electroplated nickel and silicon nitride as structural materials. The isolation between bias and signal ports is realized by using silicon nitride. In the case of a small deformation, the relation between the displacement of the vertex and the pre-bending angle is analyzed. The metal contact is realized by in-plane motion and sidewall connection. The switches were fabricated using the MetalMUMPs process from MEMSCAP. The RF testing results show that the switch has a low insertion loss of 0. 9 dB at 8 GHz and a high isolation of 30 dB below 8 GHz.

A 16×16 Micro Mirror Array for Optical Switches

This paper reports on the design, fabrication,and performance of a high-reflectivity large-rotation mirror array for MEMS （micro-electro-mechanical system） 16 × 16 optical switches. The mirror in the array can enlarge its rotation an- gles up to 90° and keep a steady state to steer the optical signal. According to the large-rotation behavior, an electro- mechanical model of the mirror is presented. By monolithic integration of fiber grooves and mirrors fabricated by a sur- face and bulk hybrid micromachining process, the coarse passive alignment of fiber-mirror-fiber can be achieved. The re- flectivity of the mirror is measured to be 93.1% ~96.3%. The switches demonstrate that the smallest fiber-mirror-fiber insertion loss is 2. ldB using OptiFocusTM collimating lensed fibers. Moreover,only about ＋- 0.01dB oscillating amplitude of insertion loss is provoked after the device is tested for 15min for 5-90Hz in the vertical vibration amplitude of 3mm.

Ultrasonic Linear Motor with Anisotropic Composite

An idea to make up the vibrating body of ultrasonic motor with anisotropic composite is proposed and a linear piezoelectric motor is developed in this paper. Relative problems such as actuating mechanism, resonant frequency are discussed theoretically. According to the feature that impulse exists between the elastic body of composite ultrasonic linear motor and the base, an impulse analysis is presented to calculate the motor′s friction driving force and frictional conversion efficiency. The impulse analysis essentially explains the reason why the ultrasonic motor has great driving force, and can be applied to analyze the non-linear ultrasonic motor.

Prestiction friction compensation in direct-drive mechatronics systems

LuGre model has been widely used in friction modeling and compensation.However,the new friction regime,named prestiction regime,cannot be accurately characterized by LuGre model in the latest research.With the extensive experimental observations of friction behaviors in the prestiction,some variables were abstracted to depict the rules in the prestiction regime.Based upon the knowledge of friction modeling,a novel friction model including the presliding regime,the gross sliding regime and the prestiction regime was then presented to overcome the shortcomings of the LuGre model.The reason that LuGre model cannot estimate the prestiction friction was analyzed in theory.Feasibility analysis of the proposed model in modeling the prestiction friction was also addressed.A parameter identification method for the proposed model based on multilevel coordinate search algorithm was presented.The proposed friction compensation strategy was composed of a nonlinear friction observer and a feedforward mechanism.The friction observer was designed to estimate the friction force in the presliding and the gross sliding regimes.And the friction force was estimated based on the model in the prestiction regime.The comparative trajectory tracking experiments were conducted on a simulator of inertially stabilization platforms among three control schemes:the single proportional–derivative(PD)control,the PD with LuGre model-based compensation and the PD with compensator based on the presented model.The experimental results reveal that the control scheme based on the proposed model has the best tracking performance.It reduces the peak-to-peak value(PPV)of tracking error to 0.2 mrad,which is improved almost 50%compared with the PD with LuGre model-based compensation.Compared to the single PD control,it reduces the PPV of error by 66.7%.

Multi-motor Drive System Based on Adjacent Coupling Error Strategy

A new control strategy named adjacent coupling error strategy is proposed to multi-motor drive system. The adjacent coupling error control scheme is developed considering the tracking speed error in one motor and the synchronous error among adjacent motors simultaneously. In the strategy, due to non-linear effects of the two mentioned errors to the motion control of motor i, an adaptive fuzzy logic controller is designed to decide the control variable of the motor drive system. The multi-motor drive system is modeled and simulated by SIMULINK. The simulated researches show that the proposed strategy improves the synchronization, stabilization, and convergence of the multi-motor system.

Design of a novel finger of DLR/HIT dextrous robot hand based on mechatronic integration

With the idea of mechatronic integration,a novel finger of the dextrous robot hand has been designed. The finger with nice envelop has four joints with three DOFs driven by three brushless DC motors with smaller size and more torque. The use of rigid gear head,bevel gears and linkage in the transmission system makes the finger more rigid. Abundant sensors such as joint angle sensors,joint torque sensors and temperature sensors are located in the finger. Integration and modularization are achieved at most by high integration of finger body,driving system,sensors and electronics.

Dynamics of mechanical system for electromechanical integrated toroidal drive under electric disturbance

Based on electromagnetics and mechanics, electromechanical coupled dynamic equations for the drive were developed. Using method of perturbation, free vibrations of the mechanical system under electric disturbance were investigated. The forced responses of the mechanical system to mechanical excitation under electric disturbance were also presented. It is known that for the system with electric disturbance, as time grows, beat occurs. When electric disturbing frequency is near to the natural frequencies of the mechanical system or their integer multiple, resonance vibrations occur. The forced responses of the mechanical system to mechanical excitation under electric disturbance are compound vibrations decided by mechanical excitation, electric disturbance and parameters of the system. The coupled resonance vibration caused by electric disturbance and mechanical excitation was discussed as well. The conditions under which above coupled resonance occurs were presented. The results show that when the difference of the excitation frequency and the perturbation frequency is equal to some order of natural frequency, coupled resonance vibrations occur.

Application of direct torque control to electric screw presses for speeding up torque response and reducing starting current

Fast response and stable torque output are crucial to the performance of electric screw presses. This paper describes the design of a direct torque control （DTC） system for speeding up torque response and reducing the starting current of electric screw presses and its application to the J58K series of numerical control electric screw presses with a dual-motor drive. The DTC drive system encompasses speed control, torque reference control, and switching frequency control. Comparison of the DTC dual-AC induction motor drive with corresponding AC servo motor drive showed that for the J58K-315 electric screw press, the DTC drive system attains a higher maximum speed （786 r/min） within a shorter time （1.13 s） during a 250 nun stroke and undergoes smaller rise in temperature （42.0 ℃） in the motor after running for 2 h at a 12 min-1 strike frequency than the AC servo motor drive does （751 r/min within 1.19 s, and 50.6 ℃ rise）. Moreover, the DTC AC induction motor drive, with no need for a tachometer or position encoder to feed back the speed or position of the motor shaft, enjoys increased reliability in a strong-shock work environment.

Electromagnetic drive system of robotic fish

With the aim to apply the electric fish into practice to assist coal mine water disaster life detection and rescue work, based on the analysis on swing propulsion movements of tail fin, this paper integrates the electromagnet technology with tail fin drive system by analyzing how the fish swims with tail fin under the law of progression. The principle, structure, and drive signals of tail fin electromagnetic drive are researched, the enforced situation of fish under eIectromagnetic driving modes are analyzed, and the experimental plat-form of tail fin electromagnetic drive is established. The best distance between electro- magnet and armature, which can realize the swing of tail fin, was researched in the experiment under water. The robotic fish structure parameters of tail fin electromagnetic drive was finalized by theoretical analysis and experimental measurement.

Measurement and Simulation of Energy Consumption of Feed Drive Systems

In this study, in order to investigate the power consumption of feed drive system, mathematical models for the single-axis experimental apparatus are developed. This apparatus can be driven by either of ball screw or linear motor and it is possible to change the mechanical properties of such as grease viscosity of the table. Then, the power consumption is simulated by proposed method based on the mathematical model of feed drive systems and the simulated results are compared with the measured results of the experimental apparatus to confirm the validity of the proposed method. In addition, it is clarified that the energy usages of the feed drive system. The energy losses of the feed drive system are divided into the loss of each part and these energy losses are calculated by the proposed method. Then, it is investigated that the influence of the velocity and friction to the energy consumption of feed drive system. As the results, it is confirmed that proposed method can accurately predict the power consumption of the ball-screw feed drive system. It is also clarified that the energy usage for both of ball-screw and linear motor drive systems.

Modern Control and Diagnostic System of Traction Vehicle with Hybrid Drive System

In paper it introduced a review of modem traction vehicle drive system with induction motor drive system （PMSM with single or dual rotor drive system） or BLDC motor with different configuration of magnetic circuits. For particular part of drive system proposed a quasi intelligent control system version smart control enables multi criteria predictive control of vehicle work. In the paper presented also a selected diagnostic procedure, enables monitoring exploitation parameters, and prediction of probable failure state. For different vehicle work state realized a simulation models and crash test of exploitations failure models.

Modeling and Analysis of Electrostatically Actuated MEMS under Combined Nonlinearities, Lorentz Force, and Mechanical Shock

This paper shows an analysis ofMEM S （micro electro mechanical systems） due to Lorentz force and mechanical shock. The formulation is based on a modified couple stress theory, the von Karman geometric nonlinearity and Reynolds equation as well. The model contains a silicon microbeam, which is encircled by a stationary plate. The non-dimensional governing equations and associated boundary conditions are then solved iteratively through the Galerkin weighted method. The results show that pull-in voltage is dependent on the geometry nonlinearity. It is also demonstrated that by increasing voltage between the silicon microbeam and stationary plate, the pull-in instability happens.

Experimental Investigation of Electric Drive Dynamics

Induction motor is used in many applications to drive an electromechanical system. Transients of the motor torque and speed are outlined by the inertia of rotating rotor. The paper deals with influence of rotor inertia to transients of motor speed. The method of speed control measurement and experimental equipment is discussed. Simulation and experimental results are compared.

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.

Single-Phase Full Bridge PWM Rectifier with Load Current Feedforward

Many conventional switching power supplies in input AC line voltage and filtering it with large electrolytic computers and low power motor drive systems operate by rectifying the capacitors. This results in undesirable side effects such as the generation of distorted input current waveform. The input power factor is also poor. Further, the input current has the shape of narrow pulses, which in turn increases its value. The reduction in input current harmonics and improved power factor operation of motor drive systems and switching power supplies are important from the energy saving point of view and also to satisfy the harmonic standards. This paper proposes a full bridge PWM rectifier with load current feedforward. The proposed approach has some advantages, including a quick response for the load fluctuation, the reduction of the number of sensors and simplified control, as compared with the conventional methods. From simulated results, it is clarified that the proposed control method is effective and useful.

Megabots Team： A Team for the Category Sumo Autonomous 3 kg

This paper deals with a method for building a mobile robot in order to transform the material into a practical guide for beginners in the study of mobile robotics. The project is divided into layers that can define the topics related to the areas of knowledge that will be used in carrying out the project. These areas are the mechanics, electronics and computing system. The mobile robot named Fable was developed accordingly to this method. It is composed by two active wheels, each one driven by DC motor with a high torque and a transmission system containing two spur gears. It has three sonars for detection of the opponent and two infrared sensors to detect a line and an Arduino Uno board is used to control all the actions of the robot.

Load Torque Compensator for Model Predictive Direct Current Control in High Power PMSM Drive Systems

The widely used cascade speed and torque controllers have a limited control performance in most high power applications due to the low switching frequency of power electronic converters and the convenience to avoid speed overshoots and oscillations for lifetime considerations. Model Predictive Direct Current Control （MPDCC） leads to an increase of torque control performance taking into account the discrete nature of inverters but temporary offsets and poor responses to load torque variations are still issues in speed control. A load torque estimator is proposed in this paper in order to further improve dynamic behavior. It compensates the load torque influence on the speed control setting a feed forward torque reference value. The benefits are twice; the speed controller reaches the speed reference value without offsets which would need to be compensated by an integrator and a better response to load torque variations is obtained since they are detected and compensated leading to small speed variations. Moreover, the influence of pararneter errors and disturbances has been analyzed and limited so that they play a minor role in operation.

Industrial Vision of High Efficiency Motors

This paper discusses the prospect of high efficiency motors based on usage in industrial sectors. In fact, energy consumption is globally classified into the industrial sector, transport system, residential and commercial building, agriculture and others sectors. In all the sectors, energy is eventually consumed by electrical appliances and equipments and the industrial sector accounts for the largest share of the overall energy consumption. The study concerns to identify the energy consumption using qualitative method. The main emphasis was given to comparison of the motor with high efficiency motors （HEMs） and traditional standard motors to investigate energy savings. According to the study, industrial sector has up to 25% of electrical energy conservation potential. Almost 70%-75% of the electrical energy consumption in industry is on account of use of electrical motors being used by pumps, fans, compressors and other motor driven system. Therefore, the potential for energy conservation through electric motors is quite high. Using high efficiency motors （HEMs） can thus reduce the losses and hence save vital energy costs. This paper will provide a contribution to electrical motors arena and will be a systematic knowledge base for researchers in this field.