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The accurate prediction of temperature rise in various parts of a machine plays a significant role in ensuring that the machine delivers the required performance avoiding failures that arise due to high temperatures. In this paper, a lumped parameter thermal model is presented for exterior-rotor axial flux switched reluctance motors. Depending on its geometry, each part of the motor is modeled as a thermal equivalent circuit based on general cylindrical or cuboidal components. A total thermal network is obtained by proper connection of these sub-circuits. The model was calibrated by a stationary test; then, running conditions were applied to the model. The sensitivity of the model to the heat transfer coefficients was investigated by considering the effect of the coefficient variation on the estimated steady-state temperatures. Results show that the winding temperature, as the hottest part of the motor, is the most sensitive to the frame-to-ambient heat transfer coefficients. 相似文献
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永磁辅助同步磁阻电机良好的运行特性与电机的电感参数密切相关,在电磁方案设计阶段需要对电感参数进行准确计算。介绍了等效交直轴法、静态场法、瞬态场法和冻结磁导率法计算交直轴电感参数的原理,并采用上述四种方法进行了电机交直轴电感参数的仿真计算。进行样机试制,并采用伏安法测试了样机电感参数,将仿真结果与测试结果进行对比,以验证各方法的准确性。结果表明,冻结磁导率法仿真得到的交直轴电感参数与实测结果的误差在3〖WTB4〗%〖WTBZ〗以内,采用冻结磁导率法的计算结果更为准确。 相似文献
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同步磁阻电机(SynRM)具有效率高、成本低、结构简单等优点,但其存在转矩脉动大等问题,会影响电机的平稳运行。为了降低SynRM的转矩脉动,需要对转子结构进行优化。以一台22 kW四极的SynRM为例,采用田口法对不同电流负载下的SynRM转子结构进行优化。确定SynRM的转子拓扑,探究SynRM转子结构的关键参数对转矩性能的影响,初步确定转子关键参数的范围。利用田口法对不同电流负载下的电机进行试验分析,得到最优转子结构参数组合,利用有限元仿真验证优化结果。为了增强转子的机械强度,在转子结构中添加径向磁桥,探究径向磁桥对电机转矩性能的影响。 相似文献
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提出一种自抗扰磁链观测器,它对永磁同步电动机电感和永磁磁链的变化具有很好的鲁棒性.永磁同步电动机由电流调节逆变器来驱动,其中d-q轴电流是由两个前馈交叉耦合的比例积分控制器来解耦调节.电流调节器反映磁链偏差的积分项用来补偿由于电机工作温度变化等原因带来的电感和永磁磁链变化.实验结果表明了该观测器的有效性和优越性. 相似文献
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Mohamed. K. Metwaly 《电力部件与系统》2017,45(11):1202-1216
This paper presents an application of direct torque and flux control (DTFC) for a four-switch three-phase inverter (FSTPI)-fed synchronous reluctance motor (SynRM) in which the saturation and iron losses' effects are involved in the machine control modeling. The DTFC switching technique for the SynRM fed by FSTPI in low-power and low-cost applications is implemented by imitating the six-switch three-phase inverter (SSTPI). By considering equal effective vectors depicted in SSTPI, the αβ stationary reference frame is represented by using six sectors. Similarly, the voltage space vector formation is constructed in FSTPI. Accordingly the SynRM performance under DTFC is precisely analyzed by considering the saturation and iron losses' effects. The DTFC behavior based on SSTPI- and FSTPI-fed SynRM is evaluated using Simulink benchmark. At different operating conditions, further simulation and experimental results of DTFC based on FSTPI dynamically confirm the effectiveness of the proposed control application on the SynRM. 相似文献
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一种永磁同步电机直接转矩控制无传感器运行优化方法 总被引:3,自引:0,他引:3
为了改进自抗扰控制器(active-disturbance rejection control,ADRC)性能,同时解决永磁同步电机(permanent magnet synchronous motor,PMSM)传统直接转矩控制(direct torque control,DTC)中存在的磁链和转矩脉动大以及机械速度传感器的使用降低系统可靠性等问题,提出一种PMSM DTC无传感器运行优化方法。设计了ADRC速度调节器,阐述了将最小二乘支持向量机(LSSVM)最优回归模型有效嵌入ADRC调节器的实现方法,对ADRC进行优化,以提高ADRC观测精度及系统动态响应速度,改善系统的抗干扰能力;同时,在两相静止坐标系下提出基于扩张状态观测器同时对定子磁链和转速进行估计的方法,以降低磁链和转矩脉动,同时实现无传感器运行。仿真和实验结果验证了该方法的可行性和有效性。 相似文献
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AbstractThis work investigates the application of the adjoint variable method (AVM) to switched reluctance motors (SRMs). A MATLAB toolbox developed by the authors estimates the sensitivities of the required objective function with respect to different geometric design parameters using at most one adjoint simulation. In this work, the AVM evaluates the sensitivities of the x and y components of the magnetic flux density, the phase flux linkage, and the electromagnetic torque of switched reluctance motors with respect to teeth height, yoke thickness, teeth pole arc angle, and teeth taper angle of both stator and rotor. The nonlinearity of the motor magnetic material is taken into consideration. The estimated sensitivities using AVM are compared with those obtained using the more accurate but time intensive central finite differences (CFD). An interior-point optimization algorithm utilizes the sensitivities of the electromagnetic torque of an SRM to maximize the motor static torque profile. Structural mapping technique is used to control the geometric design parameters through the optimization process. 相似文献
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开关磁阻电机转子斜槽结构可有效减小电磁径向力,但会导致转矩特性变化。针对该问题,给出了线性模型下斜槽转子开关磁阻电机稳态转矩的解析方法,然后建立了四相8/6极开关磁阻电机模型,采用三维有限元仿真方法,计及端部漏磁,以电流开通角、关断角和转子斜槽角度为优化参数,以平均转矩变化量最小和转矩脉动最小为优化目标,基于正交试验法设计试验方案,通过极差和方差分析确定了相应参数的优组合,并将优化前后的转矩特性进行了比较,结果表明:小的斜槽角度对转矩特性的影响并不大,优化后电机的平均转矩相比优化前只变化了16.01%,但其转矩脉动下降了23.63%。 相似文献
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钕铁硼永磁同步电动机优化设计 总被引:2,自引:0,他引:2
利用SUMT法结合改进的Hooke-Jeeves法对钕铁硼永磁同步电动机进行优化设计,并以4kW、4极钕铁硼永磁同步电动机为例,对其进行优化设计.在满足电机各项性能指标的前提下,得到电机的最佳配合尺寸,降低了电机磁钢用量,从而降低了电机的生产成本,获得了明显经济效益.由优化结果及对优化方法的评估,说明本文采用的优化方法是一种适合于NdFeB永磁同步电动机的、切实可行的电机优化方法.运用此法进行优化设计,能较快地得到电机最优化方案. 相似文献
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Mohammad Reza Tavakoli Hossein Torkaman Farzad Faradjizadeh Ebrahim Afjei 《电力部件与系统》2015,43(5):533-542
Abstract—In this article, a comprehensive method is introduced to redress eccentricity fault consequences. Two main effects of eccentricity faults include considerable increase in unbalanced magnetic force and torque ripple. Dependency of unbalanced magnetic force and torque ripple on eccentricity fault level is shown, and the possibility of compensating them via controlling currents in facing poles is proved. These objectives are accomplished through a novel converter that controls currents in poles of every phase such that one pole is responsible for nullifying unbalanced magnetic force and the facing pole is in charge of torque ripple reducing. The control algorithm is analyzed in details and through finite-element method and MATLAB/Simulink (The MathWorks, Natick, Massachusetts, USA) is implemented on a 6/4 switched reluctance motor with 30% eccentricity fault level. The proposed strategy samples the flux leakage as the index both for occurrence and criterion for compensation of unbalanced magnetic force. The suggested method is designed such that there is no need to detect eccentricity fault direction, location, and type, which makes it cost effective and practical for a wide range of switched reluctance motors and applications. 相似文献
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Mihaela Codruta Ancuti Lucian Tutelea Gheorghe-Daniel Andreescu Frede Blaabjerg Cristian Lascu Ion Boldea 《电力部件与系统》2014,42(1):91-102
This article introduces a control strategy to obtain near-maximum available torque in a wide speed range with sensorless operation via the active flux concept for permanent magnet-reluctance synchronous motor drives. A new torque dq current reference calculator is proposed, with reference torque limited by the torque/speed envelope and by maximum current constraint. This solution approximates the maximum torque per ampere below base speed and also in the flux-weakening region, where voltage limitations impose constraints on the allowable dq currents with less computational effort. Comprehensive digital simulation results (1–6000 rpm) and experimental results (50–3000 rpm at low inverter available DC voltage of 12 Vdc instead of 48 Vdc) demonstrate the effectiveness of the proposed sensorless control strategy in a wide speed range, with stable and reliable operations up to a speed equal to eight times the machine base speed (constant power speed range = 8). 相似文献
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内置式永磁同步电机弱磁调速控制 总被引:3,自引:0,他引:3
在对内置式永磁同步电机数学模型深入研究基础上,提出了一种最优弱磁路径控制策略,该控制策略是基于由直轴电流Id和交轴电流Iq所构成的状态空间,以最大电流曲线、最大磁链曲线和最小磁链转矩比曲线为边界而提出的一种最优弱磁路径。该控制策略以实现在电机任何转速下输出力矩范围最大化和电机电枢电流最小化为目标,指出了电机在各种转速下的力矩控制方法,充分挖掘电机的自身潜能,有效保证高速高精型数控机床的加工运行。仿真和实验研究表明,该控制策略可以大大提高电机的调速范围,同时保证转矩有良好的可控性。 相似文献