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直接转矩控制具有控制简单、动态响应迅速、对参数变化鲁棒性强的特点,因此得到了广泛的应用。在传统的异步电动机直接转矩控制系统中,存在电压空间矢量对定子磁链幅值和磁通角的影响,特别是低速时系统脉动大。针对此问题,文章提出了一种的新的控制方法,该方法将磁链区间细分控制与电压矢量合成结合在一起,并通过引入模糊控制算法进一步提高了转矩响应时间,且减小了转矩脉动。仿真结果表明,本控制方法可以大大减小转矩脉动,具有较好的动静态性能。 相似文献
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为了验证基于三电平逆变器异步电动机直接转矩控制系统的可行性和有效性,利用Saber仿真软件优良的模块化和分级式的系统仿真能力,建立了异步电动机直接转矩控制系统中定子磁链与电磁转矩观测器、扇区判断、空间电压开关矢量表以及二极管箝位型三电平逆变器等子系统的仿真模型,并根据直接转矩控制原理最终构建了完整的系统仿真模型。利用所构建的系统仿真模型进行了仿真实验,仿真分析结果证明建立的系统模型是有效的,表明直接转矩控制系统具有良好的动态响应性能。 相似文献
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为了解决电机传统直接转矩控制方法中存在转矩和磁链脉动大的问题,本文在研究异步发电机、正弦脉宽调制(SVPWM)、及直接转矩控制算法的基础上,提出了改进型异步发电机直接转矩控制算法。利用Matlab/Simulink仿真平台搭建了异步发电机直接转矩控制算法系统仿真模型,包括电机模块、测量模块、逆变模块、速度和转矩计算调节模块等,并进行系统的仿真分析。从结果可知,与传统异步发电机直接转矩控制算法相比较,改进型直接转矩控制系统控制精度高明显提高、响应速度得到改善、鲁棒特性好,证明了该控制算法的有效性与可行性。 相似文献
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本文介绍了间接转矩控制(ISC)的基本原理,分析了基于异步电动机预测模型的间接转矩控制系统的组成及实现方法,给出了ISC的控制算法和电机预测模型,以及该系统的实时控制实验结果。实验结果表明,ISC控制策略能够有效地改善直接转矩控制系统的低速特性。若ISC和DTC相互配合,可以实现异步电动机直接转矩控制系统在全速范围内的高性能运行。 相似文献
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本文介绍了一种在直接转矩控制中以磁链偏差、转矩偏差及磁链位置来合理选择电压矢量的方法,产利用MATLAB/SIMULINK软件对异步电动机采用三值转矩调节器直接转矩控制系统进行了仿真研究。仿真结果表明了该系统具有较好的动态性能。 相似文献
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直接转矩控制技术是目前最为优良的交流电机控制技术,数字信号处理器(DSP)的高速运算和实时处理功能为直接转矩控制技术的数字化提供了基础。本文介绍了直接转矩控制的基本原理及TMS320LF2407 DSP的特点,给出了以TMS320LF2407 DSP为核心的异步电动机直接转矩控制系统的设计方案及软硬件的实现,同时对直接转矩控制系统进行了实验和仿真,验证了直接转矩控制技术的优良性能。 相似文献
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交流电机变频调速讲座 第八讲 按定子磁链控制的异步电动机直接转矩控制系统 总被引:1,自引:0,他引:1
8.1直接转矩控制系统的原理和特点异步电动机直接转矩控制系统是继矢量控制系统之后发展起来的另一种高动态性能的交流电动机变压变频调速系统。在它的转速环里面,利用转矩反馈直接控制电动机的电磁转矩,因而得名。 相似文献
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传统的永磁同步电机直接转矩控制方法转矩响应速度快,但转矩脉动大、电流脉动大、开关频率不固定。为此,本文在分析了面贴式永磁同步电机数学模型的基础上,提出一种基于改进DTC-SVM的空间矢量脉宽调制直接转矩控制系统。提出基于Simulink的DTC-SVM伺服系统仿真模型。仿真结果表明,整个系统既保持了传统直接转矩控制的响应速度快的优点,又具有定子电流波形畸变小,转矩脉动小,系统工作稳定,抗干扰性能强的优点。 相似文献
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Kyo-Beum Lee Joong-Ho Song Ick Choy Ji-Yoon Yoo 《Power Electronics, IEEE Transactions on》2002,17(2):255-264
A torque ripple reduction technique of direct torque control (DTC) for high power induction motors driven by three-level inverters with the inverter switching frequency limited around 0.5-1 kHz level is presented. It is noted that conventional two-level DTC algorithms to reduce torque ripple are devised for applications with relatively high switching frequency above 2-3 kHz and cannot accomplish satisfactory torque ripple reduction for three-level inverter systems with such lower switching frequencies. A new DTC algorithm, especially for low switching frequency inverter system, illustrates quite reduced torque ripple characteristics all over the operating speed region. Simulation and experimental results show effectiveness of the proposed control algorithm 相似文献
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Improved torque fidelity in harmonic drive sensors through the union of two existing strategies 总被引:1,自引:0,他引:1
J.W. Sensinger R.Fff. Weir 《Mechatronics, IEEE/ASME Transactions on》2006,11(4):457-461
The torsional compliance of harmonic drives lends itself to torque sensing, but the elliptical wave generator in harmonic drives introduces a spatially dependent local torque ripple on the flexspline of harmonic drives. It is difficult to extract the applied torque signal from this local torque ripple if the applied torque is sensed at the flexspline of the harmonic drive. Previous methods have used spatially offset Wheatstone bridges or gain tuning to attenuate torque ripple. The authors have found that combining both of these techniques through a different wiring configuration can attenuate local torque ripple to /spl plusmn/0.5 N/spl middot/m, a better ripple reduction than either method alone. This local ripple reduction is adequate for large-range torque applications, but is not adequate for precision torque applications. 相似文献
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文章以无刷直流电机(BLDCM)双闭环调速系统为基础,分析脉宽调制(PWM)方式对三相六状态二二导通BLDCM控制系统的影响,提出了在PWM-ON-PWM(前30°和后30°进行PWM控制,中间60°保持恒通)方式下的转矩脉动补偿,并且将传统PI控制器用模糊PI控制取代。建立了仿真模型,采用Matlab/Simulink软件进行了仿真实验。结果表明,该控制不但能够完全消除非换相期间由于关断相出现电流而引起的电磁转矩脉动,还能够补偿由于换相而引起的转矩脉动。 相似文献
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In this paper, a novel technique for the direct torque control (DTC) of an induction motor is proposed, which overcomes the trouble of high torque ripple afflicting the conventional DTC technique. With the novel technique, the inverter voltage vector selected from the switching table is applied for the time interval needed by the torque to reach the upper (or the lower) limit of the band, where the time interval is calculated from a suitable modeling of the torque dynamics. By this approach, the control system emulates the operation of a torque hysteresis controller of analog type since the application time of the inverter voltage vector is dictated by the allowed torque excursion and not by the sampling period. It is shown by experimental results that the technique yields a considerable reduction of the torque ripple. A further and ultimate reduction is obtained by compensating for the delay inherent in the discrete-time operation of the control system. The outcome is that the torque ripple of the motor is constrained within the hysteresis band of the torque controller, for a band of customary value. An ancillary merit of the technique is the almost full elimination of the average torque error inherent in the conventional technique. If the hysteresis band is shrunk, the torque ripple is bound to swing out the band limits. Under this circumstance, an extension of the technique is developed, which helps keep the torque ripple at minimum. To assess the characteristics of the proposed DTC technique, the following quantities: average torque error, rms value of the torque ripple, and inverter switching frequency are measured for different stator flux angular speeds and hysteresis bands of the torque and flux controllers. As a comparison, the same quantities are given for the conventional DTC technique. 相似文献
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Nagase H. Okuyama T. Takahashi J. Saitoh K. 《Industrial Electronics, IEEE Transactions on》1989,36(4):504-510
The authors examine a thyristor motor torque ripple suppression method that is simple in configuration. A simplified method of calculating motor torque ripple is introduced. This method enables calculation of velocity fluctuation due to torque ripple in the vicinity of the resonant frequency. Calculation results show that operation around the resonant frequency constitutes a problem. The current amplitude control method is effective for suppressing the torque ripple at the resonant frequency. This method detects the velocity fluctuation component and controls the current amplitude to eliminate that component. The velocity fluctuation component is detectable by using a filter that has a differential element. In addition, it is shown that the characteristic of the control system can be calculated with the aid of a Bode diagram, and its effectiveness is confirmed through simulation. From simulation results, this suppression method is found to be effective in reducing the velocity fluctuation to a practical level 相似文献
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本文提出一个基于滑模控制(SMC)和空间矢量脉宽调制(SVPWM)技术对PMSMDTC转矩脉动抑制的新方法,采用滑模控制取代两个滞环比较器,得到交-直轴参考电压,用SVPWM技术调制参考电压。这样不仅可以解决滞环比较器的带宽导致的转矩脉动,还可提高精准度和响应速度,也能减小转矩脉动,仿真实验结果证明了此方法的有效性。同时还论述了PI控制器参数对系统性能的重要影响。 相似文献