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三电平双PWM变频器近年来应用广泛,而提高系统动态性能,降低直流母线电容容量一直是研究热点。针对整流侧动态性能、逆变侧与整流侧间的能量传递过程,提出了一种整流侧基于动态性能优良的直接功率控制(DPC),逆变侧基于磁场定向矢量控制(FOC),使用负载功率反馈方法的三电平双PWM变频器一体化控制策略。构建了MATLAB/simulink环境下的仿真模型,对三电平双PWM变频器系统进行了仿真研究,结果表明采用负载功率反馈方法的一体化控制策略显著降低了直流母线电压脉动,提高了系统动态性能。 相似文献
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开绕组无刷双馈风力发电机最大功率点跟踪直接转矩模糊控制研究 总被引:1,自引:0,他引:1
基于风力发电机最大功率点跟踪原理,结合无刷双馈电机无电刷和集电环的特殊结构及采用双定子磁场调制使得所需变流器容量更小的特点,提出了一种由双两电平变流器拓扑构造三电平馈电的开绕组策略,阐述了无刷双馈风力发电机最大功率点跟踪、开绕组策略及直接转矩控制、模糊控制等各部分工作原理,进而利用Matlab/Simulink仿真软件,搭建了无刷双馈风力发电机控制绕组采用双两电平SVPWM变流器馈电实现最大功率点跟踪的开绕组直接转矩模糊控制模型,并进行了详细的性能仿真,最后,通过无刷双馈电机半实物仿真实验平台,证实了所提开绕组策略的正确性和可行性,为进一步研发半实物仿真实验平台及相关控制策略提供了良好的参考与借鉴。 相似文献
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基于滞环电流控制策略,提出了一种三相四线制AC/DC双向变流器主电路设计方法,通过Matlab仿真平台,进行了一定功率条件下可控整流与有源逆变的电压、电流波形仿真,验证了主电路拓扑设计及控制策略的正确性. 相似文献
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风能作为绿色能源受到人们越来越多的关注,随着风力发电技术的迅速发展,变速恒频双馈电机风力发电技术也逐渐得到广泛的应用。本文首先建立网侧变频器的数学模型,然后使用Simulink对双馈风力发电机组网侧变换器进行了仿真研究,针对网侧变换器的整流与逆变工作状态分别加以分析。 相似文献
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在介绍通过三电平构成的整流-逆变背靠背系统的基础上,研究了三电平的空间电压矢量控制算法,通过采用基于时间因子的中点电压平衡控制方法控制中点电位偏移,进而构建无速度传感器的三电平传动系统,最后通过MATLAB/Simulink仿真分析了电机的加减速工况。结果证明系统具有稳定的性能,中点电位平衡得到了良好控制,并且应用的无速度传感器方法对异步电机的转速辨识具有良好的精度和快速的动态响应。 相似文献
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《Electric Power Systems Research》2001,58(3):157-167
A single-phase three-level pulsewidth modulation (PWM) AC/DC converter with the function of power factor corrector and active power filter is proposed to reduce harmonic currents flowing into the power system and to draw a nearly sinusoidal current with unity power factor. The circuit topology of the adopted three-level PWM AC/DC converter is based on a conventional two-level full-bridge rectifier and one AC power switch. The control signals of the power switches are derived from the voltage balance compensator, current controller and detected operation region of mains voltage. A three-level PWM voltage pattern on the AC side of the converter in each half cycle of mains frequency is generated. Computer simulations are implemented to confirm the operation of the adopted converter with the function of power factor corrector and active power filter. 相似文献
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《Electric Power Systems Research》2006,76(5):271-282
An active power filter with asymmetric inverter legs are presented to eliminate harmonics, compensate reactive power and draw the balanced line current from the AC source under balanced and unbalanced load conditions. Three inverter legs are used in the adopted voltage source inverter. In each leg, four active switches are adopted to achieve three-level pulse-width modulation (PWM). No clamped diode or flying capacitor is used in the proposed inverter. In the adopted control algorithm, a classical proportional-integral voltage controller and hysteresis current controller are used to maintain DC-link voltage constant and to track line current commands, respectively. A voltage compensator is added in the inner control loop to compensate the neutral point voltage variation due to load variation. Based on the proposed PWM control scheme, a three-level voltage pattern is generated on the AC terminal of the inverter. The system configuration and mathematical analysis are discussed in the paper. Finally, the experimental results based on a laboratory scaled down prototype are provided to verify the effectiveness of the control algorithm. 相似文献
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Jun‐Ichi Itoh Ikuya Sato Hideki Ohguchi Kazuhisa Sato Akihiro Odaka Naoya Eguchi 《Electrical Engineering in Japan》2005,152(3):65-73
This paper proposes a novel control method based on the virtual AC/DC/AC conversion for the matrix converter. The virtual AC/DC/AC conversion method is a very simple strategy to control the input current and the output voltage for the matrix converter. There are two new topics proposed in this paper. First, this paper proposes the minimum switching loss modulation on the virtual rectifier. In our proposed modulation, only two arms switching in the virtual rectifier using DC link current control by the virtual inverter can obtain clean sinusoidal input current. Second, a novel lean controlled carrier modulation on the virtual inverter is proposed. The leans of the triangle carrier are controlled by the duty ratio of the rectifier side pulse. The lean controlled carrier reduces harmonic distortion of the input current by avoiding interference between the rectifier control and the inverter control. These new proposals are confirmed by simulation and experimental results. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 152(3): 65–73, 2005; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20144 相似文献
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将矩阵变换器用于驱动无刷直流电动机,实现对无刷直流电动机的交-交直接控制.基于矩阵变换器交-直-交等效模型,提出一种新的用于驱动无刷直流电动机的矩阵变换器间接调制策略.兼顾输入输出性能,分别对整流级和逆变级应用不同的PWM调制策略.整流级应用不合零矢量调制,逆变级采用120°PWM斩控调制方式.文中对所采用的调制策略进... 相似文献
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三电平PWM整流器双环控制技术及中点电压平衡控制技术的研究 总被引:20,自引:0,他引:20
该文在建立了三电平PWM整流器系统数学模型的基础上,比较了三电平PWM整流器模型与直流电机模型的相似性,基于对控制对象的状态反馈解耦,提出把直流电机的双闭环控制应用于三电平PWM整流器中,使三电平PWM整流器具有良好的动态性能和稳态性能,并且保证输入电流波形正弦性好,实现了单位功率因数。同时,针对三电平PWM整流器所固有的直流侧电容中点电压平衡问题,提出根据每相输入电流方向和中点电压波动方向来优化选取冗余的正小矢量和负小矢量,实现中点电压平衡控制的方法。最后通过实验验证了双环控制器和控制中点电压方法的可行性和有效性。 相似文献
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针对当前电气化铁路供电系统中存在的负序、无功、谐波和电分相等问题,顺应铁路高速化、重载化的潮流,提出一种基于三相-单相变换的新型同相供电系统方案。该同相供电方式的整流侧采用不控整流电路,逆变侧采用H桥级联多电平单相SPWM变流器。由电压有效值和瞬时值双闭环控制,抑制不控整流电路的直流电压波动对逆变侧交流电压的不良影响,为机车负载提供稳定的电压支撑。分析了该新型同相供电系统的工作原理及其在不同工况下的供电性能,并在Matlab/Simulink平台上建立了系统模型。仿真结果验证了该方案的正确性与可行性。 相似文献