Novel Flux-Weakening Control of an IPMSM for Quasi-Six-Step Operation

This paper proposes a novel flux-weakening control algorithm of an interior permanent-magnet synchronous motor for “quasi” six-step operation. The proposed method is composed of feedforward and feedback paths. The feedforward path consists of 1-D lookup table, and the feedback is based on the difference between the reference voltage updated by current regulator and the output voltage limited by the overmodulation. Using this method, the flux-weakening and the antiwindup controls can be achieved simultaneously. In addition, the quasi-six-step operation can be obtained. That is, the available maximum output torque in the flux-weakening region is close to that in the six-step operation while the ability of the current control is maintained. The effectiveness of this method is proved by the experimental results.      

Flux-Weakening Regime Operation of an Interior Permanent-Magnet Synchronous Motor Drive

The interior permanent magnet (IPM) synchronous motor is compatible with extended-speed-range constant-power operation by means of flux-weakening control. Flux weakening uses stator current components to counter the fixed-amplitude magnetic airgap flux generated by the rotor magnets, performing a role similar to field weakening in a separately excited dc motor. The nature of current regulator saturation caused by the finite inverter dc source voltage is described, marked by premature torque and power degradation at high speeds in the absence of flux-weakening control. This is followed by presentation of a new flux-weakening control algorithm developed as a modification of an established feedforward IPM torque control algorithm described previously in the literature. Attractive features of this new algorithm include smooth drive transitions into and out of the flux-weakening mode, fast response, as well as automatic adjustment to changes in the dc source voltage. Simulation and empirical test results from a 3-hp laboratory IPM motor drive are used to confirm the constant-power operating envelope achieved using the new flux-weakening control algorithm.     

Online Parameter-Estimation-Based Speed Control of PM AC Motor Drive in Flux-Weakening Region

This paper presents an online parameter-estimation-based high-speed control of an interior permanent-magnet synchronous motor (IPMSM) drive. The controller designed from standard linear $d{-}q$ axis motor model with constant parameters will lead to an unsatisfactory prediction of the performance of an IPMSM owing to the magnetic saturation of this motor, particularly, at high-speed conditions. In this paper, an adaptive backstepping-based control technique has been developed for an IPMSM, wherein system parameter variations, as well as field control, will be taken into account at the design stage of the controller. The operating speed limit of the motor is expanded with the proposed parameter-estimation-based field control (PEFC). The complete drive is successfully implemented in real time for a laboratory 1-hp motor using digital signal processor board DS1102. The performance of the proposed drive is tested both in simulation and experiment at different operating conditions. A performance comparison of the proposed PEFC with the constant-parameter-based field control is also provided. The robustness of the controller for high-speed applications is evidenced by the results.      

永磁同步轮毂电机设计及其弱磁控制研究

采用有限元法设计永磁同步轮毂电机,对影响其性能的气隙磁密谐波和齿槽转矩进行优化,降低了谐波损耗和力矩波动,达到速度高、控制性能好、功率密度高的特点,提高了轮毂电机的性能。并且对轮毂电机进行弱磁控制,扩大其调速范围并且增大其扭矩,最后试制了一台内置式交流永磁同步轮毂电机样机,并对性能进行了测试,满足设计要求。     

无刷直流电动机弱磁运行效率优化控制

针对无刷直流电动机弱磁高速运行时损耗大的问题,研究最小损耗电流控制。通过分析基于瞬时无功功率的无刷直流电动机弱磁控制理论,计算d-q轴电枢反应电感,提出一种考虑铁损的电机Γ型近似等效电路,结合状态方程,推导出满足电磁损耗最小的励磁电流表达式。仿真和实验结果表明,在整个弱磁运行区间内,最小损耗电流控制能够降低电机电磁损耗,提高电机运行效率,扩大电机恒功率调速范围。     

基于DSP的永磁无刷直流电机弱磁控制系统

为实现永磁无刷直流电机(Permanent MagnetBrush lessDCMotor,简称PMBLDCM)的弱磁控制,在复合式转子结构电机本体基础上,提出了一种二模控制的有效策略,即基速下通过PWM控制实现调压调速的恒转矩运行;基速上通过控制电流超前反电势相位来控制电枢反应等效去磁,实现恒功率弱磁运行。采用DSP IPM硬件结构的控制系统成功地实现了这种控制策略,并获得接近3倍的恒功率弱磁运行范围。     

Design of a Switched Reluctance Machine for Extended Speed Operation

This paper presents results from a design study on the feasibility of employing high-efficiency switched reluctance (SR) machines in minimal hybrid-electric vehicles. The application requirements are presented and highlight the constraining influences of the vehicle drive-line topology on the machine design. The benefit of continuous phase current excitation is reported for the first time, demonstrating that constant power at an extended-speed operation can be realized with a higher number of phase winding turns per pole than would otherwise be achieved with conventional discontinuous current control. Thus, the torque/Ampere capability, when operating at or below base speed, is not as significantly compromised, an important consideration for the power inverter rating and, hence, drive system cost. The design procedure and simulated results are validated by measurements from a prototype machine. The results demonstrate the potential of SR technology for high-performance low-cost automotive applications, which often combine arduous environmental and volumetric constraints. In addition, the results highlight the benefits of continuous current control for extended-speed operation.     

永磁同步电动机弱磁控制的设计

阐述了永磁同步电动机恒功率弱磁扩速的基本原理以及弱磁扩速难的原因.基于专业电机设计软件RMXPRT和二维电磁场有限元分析软件包MAXWELL 2D,以内置径向式转子磁路结构为例,阐明了弱磁控制用永磁同步电动机电磁设计原理和方法,要求所设计的电机其恒功率弱磁扩速范围(CPSR)达两倍以上.在此基础上分析了所设计电机实际的扩速范围,并对满足设计要求(CPSR>2)的弱磁扩速用永磁同步电动机进行瞬态电磁场的仿真分析,结果表明了所设计电机的合理性.     

Novel Antiwindup of a Current Regulator of a Surface-Mounted Permanent-Magnet Motor for Flux-Weakening Control

This paper proposes a novel antiwindup method of current regulator for the drive system of a surface-mounted permanent-magnet synchronous motor at flux-weakening region. It is designed in conjunction with the synchronous-frame proportional and integral current regulator and the space vector pulse width modulation. The difference between the regulator output voltage and the saturated voltage on the$q$-axis of the regulator is used for flux-weakening control, which modifies the$d$-axis current reference. With this method, the antiwindup and the flux-weakening control can be achieved simultaneously. Since the proposed method utilizes the dc-link voltage more efficiently, it makes the motor generate higher output torque than the conventional antiwindup and/or flux-weakening control methods under the same voltage and current limitation. The effectiveness of this method is confirmed by computer simulations and experiments.     

轴向磁场无铁心永磁电机电磁力及转子机械强度的研究

轴向磁场永磁电机因其结构紧凑、功率密度高等优点获得越来越多的应用,对于无铁心轴向磁场永磁电机,转子盘体之间的轴向电磁力有可能会引起转子的变形,从而影响电机运行的可靠性。研究了轴向磁场无铁心永磁电机的电磁场及转子的机械强度,利用有限元分析方法和解析方法计算了电机两个外转子之间的电磁力。将该电磁力作用于转子盘上,利用结构有限元分析方法仿真分析转子盘体应力及最大变形,为转子结构的优化设计提供依据。     

无刷直流电动机弱磁调速研究

针对无刷直流电动机(BLDCM)在弱磁升速过程中开通角提前导通情况下常规逆变器所存在的环流问题,分析了环流产生的原因,通过Matlab建模仿真验证了环流波形.定性指出了环流对电机带载能力和功率逆变器的影响.针对十二功率管两两反向串联拓扑结构在开通角提前导通条件下所存在的相电压泵升问题,基于为电机绕组电感能量提供释放回路的思路,提出了一种新的控制逻辑方法.仿真结果表明,该方法既消除了环流,又解决了电压泵升问题,提高了BLDCM弱磁控制时的带载能力,增加了逆变器的可靠性.     

宽负荷脱硝改造的探索和实践

针对目前国内300 MW或以上机组脱硝改造后出现低负荷时不能投运脱硝系统的问题,采用了一种烟温协调型宽负荷脱硝系统方案的解决办法。介绍了该方案的特点及控制技术,工程实际应用的效果评析,以供类似工程开展参考借鉴。     

Four-Quadrant Sensorless Operation of Switched Reluctance Machine over the Wide Speed Range

Abstract

This paper presents four-quadrant sensorless control in switched reluctance machine (SRM) over the wide speed range. The proposed sensorless control technique could be employed not only at low speed with current chopping control (CCC) but also at high speed with angle position control (APC). At startup and low speed, the narrow voltage pulse is injected into the idle phases and the rotor position zone is determined by comparing the measured flux linkage with four flux linkage-current curves. The same flux linkage-current curves also can be adopted for rotor positions estimation at medium and high speeds. Two flux linkage-current characteristic curves in the inductance rising zone are employed to estimate the rotor position for motoring mode and the other two curves in the inductance falling zone are used to estimate the rotor position for braking mode. The experiments on a three-phase 12/8?pole SRM drive platform are carried out to verify the effectiveness of the proposed sensorless control technique.     

盘式对转双转子永磁同步电机的设计和特性分析

针对一种对转螺旋桨驱动用盘式对转双转子永磁同步电机进行了分析,提出了该电机的基本设计方法,得到了电机主要尺寸参数的设计方程;利用有限元软件对该电机进行了三维建模和动态仿真分析,得到了其磁路特性和主要性能参数,并重点分析了两个永磁转子存在位置差时电机总反电动势波形的特点,利用有限元结果对永磁转子所受的轴向磁拉力进行了计算和分析;最后对所设计的2.2 k W电机样机进行了试验验证。     

混合励磁同步电动机分段弱磁控制

针对混合励磁同步电动机在高速区的弱磁运行特点,首先推导出其弱磁调速过程中保持平稳运行的电流变化关系,然后在此基础上提出了一种采用模糊控制与粒子群优化算法分阶段电流调节的效率最优控制方法。该控制方法的基本思想是,当电机处于弱磁调速过渡阶段时,通过模糊控制器对电流进行初步调节,使其迅速起动或进行状态调整,获得较高的动态性能;当电机进入稳态运行阶段后,以铜耗最小化为目标,采用粒子群优化算法对电流进行进一步调整,使其实现效率最优化控制。最后,通过仿真与实验结果分析验证了上述控制方法的有效性。     

电动车用无刷双馈电动机恒功率弱磁研究

电动车用无刷双馈电动机在基速以下恒转矩运行、基速以上恒功率弱磁扩速运行.由于励磁电流可控制,理论上能够调节励磁电流实现恒功率控制.但是,由于无刷双馈电动机的非线性特性导致其反电势为不规则方波形状,类似直流电机那样采用相电压反馈控制励磁电流实现恒功率控制困难较大.利用三相电枢绕组电阻电压间接测量反电势控制励磁电流,实现无刷双馈电动机恒功率弱磁控制,保证恒功率阶段电机的出力最大,从而提高无刷双馈电动机恒功率弱磁扩速范围,满足电动车对驱动电机的要求.仿真、实验结果验证了该方法的有效性.     

铣床数控化及操作适用性改造

为扩大触头座铣槽加工能力,自行设计、加工了部分零配件,与外购件组装调试,使2台X8126B型万能工具铣床升级为数控铣床;同时为改善操作适用性,增加了主轴控制两地操作及正反转线路.实践证明:加工效率大幅提高,劳动强度明显降低,设备技术含量得以提升,具有较高的经济性.     

偏心条件下轴向磁通轮毂电机不平衡弯矩建模与分析

为了分析静态偏心和动态偏心对轴向磁通轮毂电机的影响,首先建立了未偏心时轴向磁通电机气隙磁场的准3D解析模型,该模型分别通过复数相对气隙磁导和径向修正函数考虑了开槽和边缘效应对气隙磁场的影响;然后通过分析静态偏心和动态偏心时气隙长度随时间和空间的变化,建立了偏心条件下轴向磁通电机的气隙磁场解析模型,有限元结果表明该模型可以准确预测偏心条件下任意位置的气隙磁通密度;最后根据该模型分析了偏心对轴向电机气隙磁场和电磁力的影响,提出了计算不平衡弯矩的方法。结果表明:不同于径向电机,偏心除了产生不平衡磁拉力,还会使轴向磁通电机产生与旋转方向正交的弯矩,该弯矩有导致偏心进一步加剧的趋势。     

基于实时操作系统的电子套接机控制系统设计

详细介绍了基于自行设计的强占式和非强占式相结合的实时操作系统在电子套接机中的应用,提高了电子套接机的缝纫速度和步进电机的步进步数,使控制系统达到了较高的国际水平.     

电动汽车IPMSM单电流调节器弱磁控制技术

针对电动汽车IPMSM在弱磁扩速时交直轴电流强耦合的问题,采用单电流调节器的弱磁控制方式,通过选择开关对最大转矩电流比(MTPA)控制方式和弱磁控制方式在不同运行状态下进行切换。在弱磁控制中直轴电压指令由直轴电流调节器获得,交轴电压指令则根据直轴电压值通过调节器直接给出。该方法能够对电机直流电压充分利用,使电机工作在最优工作点。建立该控制系统的Matlab/Simulink仿真模型,仿真结果分析证明该方法的可行性。最后搭建以英飞凌TC 1782为主控芯片的电动汽车驱动控制系统平台,对所提的控制策略的实际应用能力进行验证。