首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 392 毫秒
1.
高速条件下 ,无刷直流电动机的电流换向产生严重滞后 ,导致转矩下降并伴随脉动 .采用超前导通控制法 ,可有效加快换向过程 ,改善转矩输出能力 ;并采用改进的黄金分割法寻优 ,在线调整最优超前导通角 .仿真与实验结果验证了该控制方案的可行性与有效性  相似文献   

2.
针对无位置传感器单相无刷直流电机控制系统中的换相点时间不确定、换相转矩波动大两大问题.论文提出一种控制策略-相电流时分复用法,该方法在一个控制周期内的大部时分间里,电机绕组通入励磁电流被用来驱动电机旋转,在剩余的时间内,被用来检测电机转子的位置,通过精确控制提前关断功率开关管的时间,达到减小电机输出转矩的波动、提高电机的转速范围,明显提高单相无刷直流电动机无位置传感器运行时的性能,实验结果验证了提出方法的准确性和可行性.  相似文献   

3.
介绍了人工心脏轴流式血泵永磁无刷直流电机换相转矩脉动变化过程.根据影响电机换相转矩脉动的因素,给出了减小电机转矩脉动的解决方案,以使电机运行更加平稳.通过实验波形证实本结论分析正确,可以为电机减小转矩脉动作为参考.  相似文献   

4.
针对异步电动机直接转矩控制(DTC)系统在低速时由于开关频率不稳定而引起转矩脉动较大的缺点,提出了一种预测控制方法。该方法根据转矩和定子磁链的误差来确定应该施加的参考电压矢量,最后利用空间矢量脉宽调制(SVPWM)方法来合成该矢量,这样即保证了逆变器的开关频率恒定,从而大大降低转矩脉动。仿真结果表明,在低速下定子磁链轨迹近似为圆,转矩脉动不明显。  相似文献   

5.
To elucidate the principles of notable torque and flux ripple during the steady state of the conventional direct torque control (DTC) of induction machines, the factors of influence torque variation are examined. A new torque ripple minimization algorithm is proposed. The novel method eradicated the torque ripple by imposing the required stator voltage vector in each control cycle. The M and T axial components of the stator voltage are accomplished by measuring the stator flux error and the expected incremental value of the torque at every sampling time. The maximum angle rotation allowed is obtained. Experimental results showed that the proposed method combined with the space vector pulse width modulation(SVPWM) could be implemented in most existing digital drive controllers, offering high performance in both steady and transient states of the induction drives at full speed range. The result of the present work imphes that torque fluctuation could be eliminated by imposing proper stator voltage, and the proposed scheme could not only maintain constant switching frequency for the inverter, but also solve the heating problem and current harmonics in traditional induction motor drives.  相似文献   

6.
In order to deal with torque pulsation problem caused by traditional control method for brushless DC (BLDC) motor and to achieve high precision and good stability, a novel control strategy is proposed. Compared with the traditional control scheme, by using phase voltage as a control objective and making waveform of phase current approximately quasi-sinusoidal, torque ripple of BLDC motor is reduced from the original 14% to 3.4%, while toque is increased by 3.8%. Furthermore, by detecting zero-crossings of back electromotive force (BEMF) with non-conducting phases, sensorless control is realized. The new control strategy is simple. It can minimize torque ripple, increase torque, and realize sensorless control for BLDC motor. Simulation and experiments show good performance of BLDC motor by using the new control method.  相似文献   

7.
A new compensation method and an algorithm for compensating for the commutation torque ripples of the trapezoidal EMF brushless DC motor are put forward.Simulation and experimental results show that this method is correct and practical.  相似文献   

8.
1  Introduction Withthedevelopmentofthefrequencyconversiontechnology ,thefrequencyconvertersareextensivelyemployedinVVVFdrivesystems.Theyareusedtorealizesoftstartingoftheinductionmotor ,whichisoneoftheiradvantages.Nevertheless,inpractice ,thein verter moto…  相似文献   

9.
异步电机按定子磁链定向的转矩连续控制   总被引:5,自引:0,他引:5  
NomenclatureJmomentofinertiaoftheload(motorinclude)is,ir,imstator,rotorandmagnetizingcurrentus,urstatorandrotorvoltageLs,Lr,Lmstator,rotorandmagnetizinginductanceLσtotalleakageinductanceRs,RrstatorandrotorresistanceNppolepairsΨs,Ψr,Ψσstator,rotorandtotalle…  相似文献   

10.
对PMSM控制系统采用SVPWM和SPWM两种调制方法的性能进行对比,SVPWM方案较SPWM方案,不仅提高了逆变器的直流电压利用率,且减小了转矩脉动.  相似文献   

11.
1 Introduction Itiswellknownthatthetorquedevelopedbyapermanentmagnetbrushlessdcmotorisproportionaltothemagnitudeofmotorphasecurrents.ThislinearrelationshipmakesitconvenienttocontrolBLDCMtorqueproductionbyregulatingthemotorphasecurrents[1].Inthispaper,th…  相似文献   

12.
为深入研究无刷直流电机的控制问题,基于PIC16F877单片机构建了电机控制系统;采用绕组Y联结三相全控桥式电路设计了两两导通式换相控制模块,并给出了控制字表;研究了基于PWM法的变压调速技术,并给出了正、反转控制方法;另外,还对软件设计中的各程序模块进行了阐述。  相似文献   

13.
当今世界由于能源短缺、环境污染以及气候变暖的影响,全球汽车业特别是欧美以及日本等发达国家采取各种措施和政策大力发展电动汽车.在各种类型的车用电动机中,永磁同步电动车由于低噪声、体积小、功率密度大、转动惯量小、脉动转矩小、控制精度高等优点,受到全世界各大汽车厂家的重视.永磁同步电动机具有特殊的构造和性能特点,可以利用基于SVPWM的矢量控制法进行其性能分析和控制,最后得出仿真结果.  相似文献   

14.
15.
电流滞环跟踪PWM控制技术能较好地得到三相对称正弦波电流,以电流滞环跟踪PWM控制器为内环,转速外环调节器选用PI调节器,建立异步电动机双闭环调速系统.建立系统主电路及控制电路进行仿真模型,主电路由异步电动机模块、电动机测量单元模块、逆变器模块、直流电源、负载模块等组成,控制电路由转速给定信号、转速调节器、电流给定信号及电流滞环跟踪控制器等组成.仿真得到电流、转速及电磁转矩曲线,验证了方法的有效性.  相似文献   

16.
In this paper, a design method for ocean wave permanent magnet synchronous generator(PMSG)is proposed with new performance criteria to obtain better output performance at the cost of less permanent magnet material. Besides, a simple equivalent analytical geometry method is put forward to calculate the sizes of permanent magnets. Based on geometric and electromagnetic models, four types of rotor structures are compared, i.e., embedded, tangential, tile surface mount and convex surface mount structures. The designs and comparisons of machine are performed with the same permanent magnet volume. Moreover, the influences of mechanical pole-arc coefficient of tile surface mount PMSG on electrical efficiency, output power, material corrosion, core loss, and torque ripple are investigated. Finite-element analysis method is applied to verify the results using Ansoft/Maxwell.  相似文献   

17.
一种新型高功率密度的正弦波永磁电机   总被引:1,自引:0,他引:1  
A novel high power-density PMSM (permanent magnetic synchronous motor) with independent magnetic flux path for each phase is proposed in the paper.The complex mathematic model of PMSM is simplified by decoupling of magnetic flux paths between motor phases.In addition,harmonic compoments are lowered through optimum design of EMF (electric motive force) wave.Thus the ripple torque caused by EMF wave distortion is suppressed.  相似文献   

18.
以新型4相24极车用无刷直流电动机为研究对象,采用改进遗传算法对其转速控制系统进行了优化设计。该遗传算法在相当程度上解决了标准遗传算法搜索效率低和早熟收敛的问题。仿真结果表明:相对于传统的3相6拍无刷直流电动机,采用改进遗传算法转速控制系统的4相24极无刷直流电动机具有转矩脉动较低、输出相应快速、稳态性能好以及抗干扰能力强等优点。  相似文献   

19.
从能量、电量和电压三个平衡关系出发,分析了静电除尘装置中倍压整流电路的输出电压与负载、倍压整流电路元件参数、升压变压器分布参数、PWM逆变电路的工作状态的数量关系,给出了它们的关系表达式,并把计算结果和实际装置的实际输出进行了对照,说明分析结果是符合实际情况的,同时也指出了分析结果与实际情况不完全符合的地方,为以后进一步的分析研究指出了方向.  相似文献   

20.
1 Introduction Thedevelopmentofelectricvehicleshastakenonanacceleratedpacetofulfilltheneedofenvironmentprotectionandenergyconservation .However ,thedisadvantagesoflowenergydensityandshortperiodbetweenchargeshavebeenthebarriersforelectricvehiclestoenterthemarket.HybridEVsovercomethesebarriersandpossessesnearlythesameperfor manceasthetraditionalfuelvehicles.Therefore ,asanewtransportationtoolthatcanmeetrequirementsforenvironment protectionaswellashigh perfor mance ,hybridEVhasagoodmarketpote…  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号