Implementation of Hybrid Control for Motor Drives

This paper presents the implementation of a hybrid-control strategy applied to a permanent-magnet synchronous-motor (PMSM) drive. Hybrid control is a general approach for control of a switching-based hybrid system (HS). This class of HS includes a continuous process controlled by a discrete controller with a finite number of states. In the case of ac motor drives, in contrast to conventional vector control like proportional-integral control or predictive control, where the inverter is not taken into account by the controller, hybrid control integrates the inverter model and considers the state of the inverter as a control variable. It allows to obtain faster torque dynamics than vector-control algorithms. The hybrid control algorithm requires both computing velocity for real-time implementation and code flexibility for management of low-performance functions and analog-digital interfaces. Codesign appears as a promising methodology for partitioning hybrid-control algorithm between software (flexible) and hardware (velocity) while taking care of overall time constrains. In this paper, the implementation of hybrid-control algorithm for a PMSM drive is performed through a codesign approach on an Excalibur board, embedding a CPU-core (Nios-2 by Altera) inside an APEX20KE200EFC484-2X field-programmable gate array. The partitioning of software and hardware parts is explained. Experimental results show the effectiveness of the implementation. Performances, advantages, and limitations are discussed.     

两相混合式步进电机细分驱动

为了设计一款基于数字信号处理器和功率驱动芯片的两相混合式步进电机细分控制电路,通过分析两相步进电机运行特性及细分驱动原理,使用数字信号处理器计算细分电流数据和产生控制用脉宽调制波形,简化了系统构成。驱动器能明显提高步进电动机的运行精度,改善低频振荡的现象,可实现细分级别的任意设置,能根据不同应用场合使用不同细分数来驱动步进电机。     

A Hybrid Solution for Load-Commutated-Inverter-Fed Induction Motor Drives

To validate the proposed topology and control algorithm, the prototype hybrid system was developed using an LCI, a phasecontrolled rectifier, and a VSI. An insulated- gate-bipolar-transistor （IGBT）-based commercial inverter （SEMIKRON） was used as a VSI. In addition, a prototype of a phase-controlled rectifier and an LCI was fabricated in the laboratory.     

Distributed Control of Hybrid Motor Drives

The hybrid inverter fed motor drive with two cascaded multilevel inverters is an attractive option for high performance high power applications such as naval ship propulsion systems due to a number of unique features. There is a natural split between a higher-voltage lower-frequency “bulk” inverter and a lower-voltage higher-frequency “conditioning” inverter in the cascaded system which matches the availability of semiconductor devices. Furthermore, the bulk inverter may be a commercial-off-the-shelf (COTS) motor drive meaning that only the conditioning inverter needs to be custom made. However, a drive involving a COTS bulk inverter would require a distributed conditioning inverter control which works completely independent of the bulk inverter control. In this paper, a set of distributed control methods are developed for the hybrid inverter drive with cascaded bulk and conditioning inverters, requiring only single dc source. Moreover, a solution to the practical problem of instant synchronization between the two inverters is presented. Laboratory measurements on a 3.7-kW induction motor drive validate the proposed control. Various practical considerations (such as low$m$-index performance and capacitor precharging options) are discussed and their solutions provided.     

Hybrid Electric Vehicles: Architecture and Motor Drives

Electric traction is one of the most promising technologies that can lead to significant improvements in vehicle performance, energy utilization efficiency, and polluting emissions. Among several technologies, hybrid electric vehicle (HEV) traction is the most promising technology that has the advantages of high performance, high fuel efficiency, low emissions, and long operating range. Moreover, the technologies of all the component hardware are technically and markedly available. At present, almost all the major automotive manufacturers are developing hybrid electric vehicles, and some of them have marketed their productions, such as Toyota and Honda. This paper reviews the present technologies of HEVs in the range of drivetrain configuration, electric motor drives, and energy storages     

Optimization and Evaluation of Torque-Sharing Functions for Torque Ripple Minimization in Switched Reluctance Motor Drives

Two improved torque-sharing functions for implementing torque ripple minimization (TRM) control are presented in this paper. The proposed torque-sharing functions are dependent on the turn- on angle, overlap angle, and the expected torque. This study shows that for a given torque the turn-on angle and the overlap angle have significant effects upon speed range, maximum speed, copper loss, and efficiency. Hence, genetic algorithm is used to optimize the turn-on angle and the overlap angle at various expected torque demands operating under the proposed TRM control in order to maximize the speed range and minimize the copper loss. Furthermore, four torque-sharing functions are used to derive the optimized results. At the same time, a fast and accurate online approach to compute the optimal turn-on and overlap angles is proposed. Therefore, this paper provides a valuable method to improve the performances of switched reluctance motor drives operating under TRM control.      

A Novel MagPipe Pipeline Transportation System Using Linear Motor Drives

A novel capsule pipeline transportation system using linear motor drives, called Magplane MagPipe, is under development with the intention to replace trucks and railways for hauling materials from the mine to the rail head, power plant, or processing plant with reduced operating cost and energy consumption. The initial demonstration of a MagPipe line in Inner Mongolia will be a 500-m-long double-pipe coal transport system with the design transportation capacity of 3 Mega-Mg per year. The pipeline consists of 6-m-long plastic pipe modules with an I-beam suspension system inside the pipe to carry sets of five coupled capsules. The pipe will also contain noncontinuous motor winding modules spaced at 50-m intervals. A set of Halbach-arrayed permanent magnets on the bottom of the capsules interact with the linear motor windings to provide propulsion. The motor is driven by variable frequency drives outside the pipe to control the speed. This paper briefly describes the overall MagPipe pipeline transportation system, including the preliminary conclusions of the linear synchronous motor analysis.      

Design and Control of a Linear Propulsion System for an Elevator Using Linear Switched Reluctance Motor Drives

Linear switched reluctance motors (LSRMs) for the primary propulsion of a ship elevator is proposed and investigated for the first time in this paper. To achieve the stated objective, a new type of LSRM is proposed with twin stators and a translator between them with no back iron in the translator. The proposed configuration of the LSRM is designed, simulated, analyzed, compared with traditional LSRMs, and verified by experimental measurements. The number of LSRM propulsion subsystems required is studied with a view to minimize their weights and an optimization study for that purpose is developed. Unique placement of the LSRM propulsion systems on the elevator is presented. The propulsion force is generated using one phase or multiphase excitation. To reduce propulsion force pulsations, a major requirement in elevators, controlled multiphase excitation using one of the known force distribution functions (FDF) is an acceptable solution. In this paper, it is proved that the currently available FDFs are able to reduce the force pulsations but are not able to meet the peak force command for the system. Consequently, the velocity and position control do not meet even the elementary performance requirements any more. A new FDF is proposed in this paper and presented to overcome the problem caused by a conventional FDF. The control system with the proposed FDF is derived and integrated into velocity and position controllers. Extensive dynamic simulation and experimental verification of the proposed LSRM with the novel FDF is proved to give superior performance in this paper. Such high performance capable of meeting vertical elevator applications is demonstrated.     

未来电机驱动系统的关键技术

2005年9月在我国南京召开的第8届国际电机与系统会议（1CMS’2005）上，美国威斯康星-麦迪森（Wisconsin-Madison）大学的Robert D．Lorenz教授发表了题为“未来电机驱动的关键技术”一文。在该文中，R．D．Lorenz教授介绍了至今为止他所领导的研究小组的科研成果，提出了影响未来电机拖动系统的五项关键技术。本文介绍该文的主要内容和相关动向。     

Power Electronics and Motor Drives in Electric, Hybrid Electric, and Plug-In Hybrid Electric Vehicles

With the requirements for reducing emissions and improving fuel economy, automotive companies are developing electric, hybrid electric, and plug-in hybrid electric vehicles. Power electronics is an enabling technology for the development of these environmentally friendlier vehicles and implementing the advanced electrical architectures to meet the demands for increased electric loads. In this paper, a brief review of the current trends and future vehicle strategies and the function of power electronic subsystems are described. The requirements of power electronic components and electric motor drives for the successful development of these vehicles are also presented.     

直线电机力常数快速测定方法

介绍了直线电机的应用领域及其实用前景,并对直线电机的工作原理做了具体的分析,重点研究了电机力常数的一种快速测定法,并通过实验验证了该方法的可行性与有效性。     

DC-Link Current Minimization for High-Power Current-Source Motor Drives

In this paper, a loss reduction and dc-link current minimization strategy for a high-power current-source inverter (CSI) fed drive is proposed. The proposed strategy consists of an inverter maximum modulation index control scheme and a flux optimization algorithm. Specifically, in the inverter modulation index control, the CSI modulation index is kept at the maximum value while the current-source rectifier (CSR) is used to regulate a reduced variable dc-link current, and therefore, to control the motor current magnitude. This control scheme can effectively reduce the dc-link current, and at the same time, improve the line-side and motor-side waveforms. On the other hand, for the optimized flux control, the relationship between the rotor flux and the dc-link current is first investigated thoroughly. Based on this analysis, the dc-link current from the maximum inverter modulation index control can be minimized further by optimizing the rotor flux according to system variables such as the motor speed, the applied torque, and the motor-side capacitor size. With the proposed dc current minimization strategy, the losses in the semiconductor devices and the dc link can be reduced, and the drive current rating could be lowered. Both simulation and experimental results on a 4.16-kV 600-hp CSI-fed drive system are obtained to verify the effectiveness of the proposed strategy.      

COT模式下内置纹波补偿技术的Buck变换器

当输出旁路电容为陶瓷电容等低等效串联电阻(equivalent series resistance, ESR)电容时,传统固定导通时间(constant on-time, COT)模式下的同步降压变换器容易出现周期性振荡现象。对此,提出一种可内置于芯片的纹波补偿技术。通过将与ESR电压纹波成比例同步变化的量注入到补偿电路中,并将该电压与直流参考电压比较,以实现当使用低ESR电容时,COT架构的降压器能稳定工作。同时通过仿真及实验结果验证了对稳定性和纹波补偿相关分析的正确性。     

COT架构降压型变换器片上纹波补偿电路

基于0.18 μm BCD工艺,设计了适用于电压模式恒定导通时间(COT)架构DC-DC降压型变换器的纹波补偿电路。分析了使用电解电容作为输出电容以及片外纹波补偿电路的缺点,并设计了一种新颖的片内纹波补偿电路来克服这些缺点。在芯片系统典型应用环境下,利用Cadence和Hspice软件进行电路设计和仿真。结果表明,在电源电压为5 V,温度为25 ℃的条件下,芯片输出电压的纹波仅为2.15 mV,通过纹波补偿电路的反馈电压的纹波为37 mV,完全满足系统稳定要求。当温度在-20 ℃~125 ℃内变化时,输出最大纹波仅为12.6 mV。     

气隙大小对混合式步进电机转矩的影响

考察了一台两相混合式步进电机(57 BYG060)的转矩,并讨论了其与气隙长度的关系,指出随着气隙的增长,转矩的波形会恶化,高次谐波的含量开始占主要地位。可见在转矩的计算中考虑加工和成本将给混合步进电机的设计提供一个有意义的判断依据。     

Multicarrier PWM With DC-Link Ripple Feedforward Compensation for Multilevel Inverters

Like most power converter topologies, multilevel inverters are controlled with modulation techniques that are conceptually based on nonlinear waveform synthesis assuming constant dc-link voltages. However, real applications have load and supply dependent dc-links that usually present important low frequency ripple, which is also modulated and transmitted to the load, generating undesirable low frequency voltage and current distortion. This paper introduces a simple but effective dc-link ripple feedforward strategy into traditional carrier-based modulation techniques. The dc-link ripples are measured and used to modify the carriers or the reference directly in the modulation stage. Simulation and experimental results show the accuracy of the proposed method, eliminating low order harmonics in the load current.     

Adaptive Approach to Motion Controller of Linear Induction Motor with Friction Compensation

In this paper, we propose a nonlinear adaptive controller and an adaptive backstepping controller for linear induction motors to achieve position tracking. A nonlinear transformation is proposed to facilitate controller design. In addition, the very unique end effect of the linear induction motor is also considered and is well taken care of in our controller design. We also consider the effect of friction dynamics and employ observer-based compensation to cope with the friction force. A stability analysis based on Lyapunov theory is also performed to guarantee that the controller design here can stabilize the system. Also, the computer simulations and experiments are conducted to demonstrate the performance of our various controller design.     

异步电机变频调速中的高转矩——电流比性能

现将文献[1]所提出的定子电阻在线自校正技术用于异步电机变频调速的起动和运行，从而获得了高转矩-电流比的性能，本文示出了一些重要的仿真结果，并对其进行了评述。     

A Microprocessor-Controlled High-Accuracy Wide-Range Speed Regulator for Motor Drives

A new speed measurement system, which is suitable for microprocessor-based motor drive, and its application to speed regulator are explained.     

步进电机控制自整角机生成正弦控制信号方法

介绍了一种步进电机控制自整角机生成正弦信号的方法。通过上位机软件将标准正弦信号离散化,转化成能反应正弦变化规律的定时器溢出率数据,单片机用接收的溢出率数据控制步进电机按正弦规律转动,步进电机通过机械传动器带动自整角机转子转动,生成正弦测试信号。测试结果显示,该方法可满足设计要求,并能对输入正弦信号的各参数进行随意修改。