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基于前馈补偿的SPWM矩阵变换器控制策略研究 总被引:9,自引:3,他引:9
矩阵变换器是一种AC/AC直接变换器,电网的任何非正常输入将直接恶化其输出电压特性。文中基于SPWM矩阵变换器提出了一种前馈补偿方案。通过检测输入线电压包络,对参考正弦进行预调制,使得正弦脉宽调制输出脉冲在宽度上给予自适应地补偿。文章分析了补偿原理并介绍了实现方法。采用Matlab/Simulink对补偿前后的输出特性进行了仿真对比 。分析和仿真表明该方案可以有效地改善矩阵变换器在非正常条件下的输出特性,验证了方案的有效性和正确性。该方案具有简单易行的优点,既便于硬件实现,又便于数字实现,而且计算量小。 相似文献
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首次提出并深入分析研究了一类全数字化技术,与电网电压n倍频或n分频信号同步的基准正弦电路,并给出了关键电路参数设计准则与试验结果,试验结果与理论分析一致。该基准正弦电路具有输出正弦电压与电网电压n倍频或n分频信号同步,THD小,幅值可调且不受电网电压波动的影响,简单实用,价格低廉等优点,在高频交流环节AC/AC变频变换系统和UPS中具有重要应用价值。 相似文献
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Chun‐An Cheng Tsung‐Yuan Chung 《International Journal of Circuit Theory and Applications》2016,44(11):1942-1958
This paper proposes a single‐stage light‐emitting diode (LED) driver that offers power‐factor correction and digital pulse–width modulation (PWM) dimming capability for streetlight applications. The presented LED streetlight driver integrates an alternating current–direct current (AC–DC) converter with coupled inductors and a half‐bridge‐type LLC DC–DC resonant converter into a single‐stage circuit topology. The sub‐circuit of the AC–DC converter with coupled inductors is designed to be operated in discontinuous‐conduction mode for achieving input‐current shaping. Zero‐voltage switching of two active power switches and zero‐current switching of two output‐rectifier diodes in the presented LED driver decrease the switching losses; thus, the circuit efficiency is increased. A prototype driver for powering a 144‐W‐rated LED streetlight module with input utility‐line voltages ranging from 100 to 120 V is implemented and tested. The proposed streetlight driver features cost‐effectiveness, high circuit efficiency, high power factor, low levels of input‐current harmonics, and a digital PWM dimming capability ranging from 20% to 100% output rated LED power, which is fulfilled by a micro‐controller. Satisfying experimental results, including dimming tests, verify the feasibility of the proposed LED streetlight driver. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
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Dong-Choon Lee G-Myoung Lee Ki-Do Lee 《Industry Applications, IEEE Transactions on》2000,36(3):826-833
In this paper, a fast voltage control strategy of three-phase AC/DC pulsewidth modulation (PWM) converters applying a feedback linearization technique is proposed. First, incorporating the power balance of the input and output sides in system modeling, a nonlinear model of the PWM converter is derived with state variables such as AC input currents and DC output voltage. Then, by input-output feedback linearization, the system is linearized and a state feedback control law is obtained by pole placement. With this control scheme, output voltage responses become faster than those in a conventional cascade control structure. For robust control to parameter variations, integrators are added to the exact feedback control law. Since the fast voltage control is feasible for load changes, it is shown that the DC electrolytic capacitor size can be reduced. In addition, the capacitor current is analyzed for size reduction of the capacitor. As is usual with PWM converters, the input current is regulated to be sinusoidal and the source power factor can be controlled at unity. The experimental results are provided to verify the validity of the proposed control algorithm for a 1.5 kVA insulated gate bipolar transistor PWM converter system 相似文献
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矩阵变换器是一种AC/AC变换器,它具有正弦输入电流、正弦输出电压、能量双向流动及体积小的优点,但存在着控制方法复杂,开关器件和保护元器件太多的问题.近年来提出的双桥矩阵变换器具有矩阵变换器的优点,同时其控制方法更简单,所用开关元件数目更少.论述了双桥矩阵变换器的原理,讨论了变换器的PWM控制策略以及基于线电压符号的换流方法,提出了整流级、逆变级单独控制,整流级开关频率为10kHz、逆变级开关频率为2kHz的新颖双桥矩阵变换器方案,给出了仿真和实验结果. 相似文献
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Kyungmin Sung Hajime Nakakoji Kosuke Kobayashi Yukihiko Sato 《Electrical Engineering in Japan》2005,151(4):55-64
The matrix converter is a three‐phase AC‐to‐AC direct converter without any energy storage requirement such as DC link capacitors. However, the matrix converter has some practical problems such as the necessity for bidirectional power devices, necessity for special commutation sequence, and complexity of the control method. Thus, there are no practical systems in which matrix converters are used. In this paper, the control strategy for matrix converters with basic configuration is investigated so as to realize practical matrix converters. First, the necessity of the phase detector for the input voltage and the output current sensor is pointed out from the viewpoint of realization of the basic operation. With these sensors required in the basic configuration, the instantaneous control of the output current is realized. It is also pointed out that three‐phase switching is effective in improving the input current waveforms. Some methods for implementation of three‐phase switching are proposed. The effectiveness of the proposed control methods is confirmed by some experimental results employing a test system. © 2005 Wiley Periodicals, Inc. Electr Eng Jpn, 151(4): 55–64, 2005; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20031 相似文献
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Shuo Liu Baoming Ge Xinjian Jiang Haitham Abu‐Rub Fang Zheng Peng 《International Journal of Circuit Theory and Applications》2015,43(11):1775-1793
Conventional matrix converters have a limited voltage gain less than 0.866 and also require many power switches and additional input filter that ensures a low input current harmonics to the grid. Quasi‐Z source (qZS) indirect matrix converter can provide high voltage gain and ensure a sinusoidal input current without additional input filter, which requires 12 power switches in rectifier stage. In this paper, a simplified qZS indirect matrix converter is proposed to overcome aforementioned limitations and achieve (1) higher voltage gain than 0.866, (2) less power switches, and (3) LC‐filter function integrated in qZS network to avoid additional filter. The new converter's operating principle and equivalent circuits are analyzed, and the modulation method is presented. The input current closed‐loop control is employed to implement sinusoidal input current waveform even though the proposed converter has less power switches and without extra input filter. A test bench is used to verify the simplified qZS indirect matrix converter and control methods. Simulation and experimental results identically validate the proposed converter system with wide voltage gain range and low input current harmonics. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Dynamic model development and control for multiple‐output flyback converters in DCM and CCM 下载免费PDF全文
Hossein Delavaripour Behzad Mirzaeian Dehkordi Ehsan Adib Hossein Abootorabi Zarchi 《International Journal of Circuit Theory and Applications》2018,46(6):1228-1248
Multiple‐output flyback converters are widely used in switching power supplies due to their low component count and cost‐effective structure. The main problem of this structure is how to balance output voltages in different load conditions. This paper proposes a new approach for single‐input multiple‐output flyback converters operating in DCM and CCM by a small‐signal averaged model. The averaged model is derived by presenting the piecewise‐linear waveform for the inductor currents inside the converter. In DCM, the magnetizing current and currents through the output windings reach zero when the switch is turned off. In CCM, the magnetizing current of the converter is continuous over a switching interval and this possibility exists that only some of the output diodes completely conduct when the switch is off. The proposed model of the converter can be used in a wide range of operations within identical and non‐identical loading conditions. Using a laboratory prototype, several case studies and input‐to‐output transfer functions are considered to verify the proposed model. The controller design is performed for the both CCM and DCM, and then dynamic characteristics of the overall system are evaluated. 相似文献
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双Buck双向交流斩波器 总被引:1,自引:0,他引:1
提出一种新颖的双降压式交流斩波器。传统交流斩波器换流时必须遵循严格的换流次序,存在换流时器件电压尖峰过高的问题;一般采用等占空比调制,对交流系统已有的谐波畸变没有任何抑制能力。双降压式交流斩波器可实现AC/AC直接降压变换,或反方向的AC/AC直接升压变换。采用电流单向开关和半周工作方式,结构简单、所需器件较少;由于电路结构的内在特点,无桥臂直通的可能,功率器件可同时导通,从根本上消除了换流电压尖峰;采用滞环电流控制方案的双降压交流斩波器具有良好迅速的输出电能瞬态调节能力,可得到高质量的输出电压波形。试验验证了以上分析的正确性。 相似文献
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《International Journal of Electrical Power & Energy Systems》2013,45(1):219-226
This paper presents the application of the hysteresis band current controller (HBCC) technique to the three phase pulse width modulation (PWM) AC chopper used for the purpose of controlling the magnitude of the sinusoidal currents and voltages applied to an AC load. If the HBCC technique used in the inverters is directly employed in the three phase PWM AC chopper, it causes the AC chopper to fail to provide balanced three phase sinusoidal currents for a three phase AC load. In return, this situation leads some unavoidable and serious faults to occur in the hardware of the three phase PWM AC chopper. In respect to this case, the detailed analysis expressing the related faults is presented. Consequently, for the first time, a novel HBCC technique overcoming these faults is proposed for the three phase PWM AC chopper. The proposed method is tested under various operating conditions and a very precise control performance is achieved. Simulation results prove the feasibility and validity of the proposed method. 相似文献
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交-交矩阵变换器以其单位输入功率因数和良好的正弦输入电流和输出电压等优点,被誉为"绿色"变换器.它可消除目前多样性负载给电网带来的严重谐波污染和低功率因数等负面影响,在电力电子领域蕴藏着良好的应用前景.针对可能出现的输入电压小对称情况,改进了双空间矢量调制策略,有效抑制了因输入电压不对称而引起的输出电压谐波,得到了对称的三相输出电压.为验证改进方法的正确性,利用数字信号处理器(Digital Signal Processing,简称DSP)和复杂可编程逻辑器(Complex Programmable Logic Device,简称CPLD)泽码电路作为控制器,制作了原理样机,并对改进策略进行了实验验证,给出了实验波形. 相似文献
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双PWM变换器励磁的交流励磁发电机励磁系统设计 总被引:7,自引:3,他引:4
分析了基于动态同步坐标轴系的交流励磁发电机双通道解耦励磁控制策略,提出了采用具有优良输入、输出特性的双脉宽调制(PWM)控制交 — 直 — 交电压型变频器作为交流励磁发电机的励磁电源。采用高速数字信号处理器TMS320F2812设计实现了双PWM变换器励磁的交流励磁发电机励磁系统实验平台。通过实验研究表明:基于动态同步坐标轴系的双通道解耦励磁控制策略能够实现交流励磁发电机有功、无功和转速的独立调节,发电机具备良好的动态响应能力;双PWM变换器具有功率双向流动、输入和输出谐波电流小、动态性能优良、功率因数可调等优点,是交流励磁发电机的理想励磁电源。 相似文献
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Josep M. Olm Domingo Biel Mario Spinetti‐Rivera Enric Fossas 《International Journal of Circuit Theory and Applications》2012,40(8):777-792
The achievement of step‐up inversion with a boost DC/AC converter requires appropriate periodic references for inductor currents, which have to satisfy ordinary differential equations (ODE) of the Abel type. These are equations with highly unstable solutions for which the existence of periodic solutions remains unproved. Hence, the studies reported so far in this subject obtain periodic output voltages that approximately track the expected profile using different periodic current references that do not exactly satisfy the Abel ODE. However, neither an explanation of why are periodic output voltages still obtained, nor an assessment of the output voltage error is provided. This paper analyzes the effect of using periodic current references in a Lyapunov‐based controlled boost DC/AC converter performing step‐up inversion tasks. It is shown that, for sufficiently accurate current references, the system exhibits asymptotically stable periodic solutions with bounded error. Moreover, the paper propounds the use of Harmonic Balance (HB)‐based techniques to obtain such current references. Simulation and experimental results confirm that this choice yields periodic output voltages with an error that may be lowered using higher HB approximations. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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一种提高矩阵变换器电压增益的空间矢量调制法 总被引:2,自引:1,他引:1
与传统的电压源型逆变器相比,矩阵变换器主要的缺点之一是在输入及输出电流为正弦时,输出输入电压传输比限制在0.866。为克服此缺点,在传统的矩阵变换器空间矢量调制方法的基础上,提出了一种提高电压增益的调制策略,进行了详细说明,概念清楚、控制简单,不需要复杂的数学计算。此调制策略没有使用零矢量,较传统方法换流数量减少,输出输入电压传输比提高到0.95以上,但输出电压及输入电流波形出现了一定程度的畸变。通过仿真证实了理论分析,也显示了此调制策略的优缺点。 相似文献