共查询到20条相似文献,搜索用时 31 毫秒
1.
设计了一种基于ADP3806的高功率发光二极管(LED)的高效驱动电路。ADP3806是一款开关模式电源控制器,拥有双环路恒定电压和恒定电流控制、远程精确电流检测以及关断和可编程可同步开关频率,能提供恒定电流。同时在设计中利用单端原边电感转换器(SEPIC),其可以提供一种可以高于或低于输入电压的输出电压,在适当的占空比下工作,使连续传导模式(CCM)和脉冲宽度调制(PWM)控制变得简单,提高了效率,并且避免由变压器泄漏电感带来的电压尖峰和振铃。从而在需要进行升压和降压转换来同时驱动多个高功率LED的场合,这个设计是非常适合的。 相似文献
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《Power Electronics, IEEE Transactions on》2009,24(8):2032-2042
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Dênis De Castro Pereira Márcio Renato Da Silva Elder Mateus Silva 《International Journal of Electronics》2013,100(8):1361-1381
High power factor rectifiers have been consolidated as an effective solution to improve power quality indices in terms of input power factor correction, reduction in the total harmonic distortion of the input current and also regulated dc voltages. Within this context, this subject has motivated the introduction of numerous converter topologies based on classic dc-dc structures associated with novel control techniques, thus leading to the manufacturing of dedicated integrated circuits that allow high input power factor by adding a front-end stage to switch-mode converters. In particular, boost converters in continuous current mode (CCM) are widely employed since they allow obtaining minimised electromagnetic interference levels. This work is concerned with a literature review involving relevant ac-dc single-phase boost-based topologies with high input power factor. The evolution of aspects regarding the conventional boost converter is shown in terms of improved characteristics inherent to other ac-dc boost converters. Additionally, the work intends to be a fast and concise reference to single-phase ac-dc boost converters operating in CCM for engineers, researchers and experts in the field of power electronics by properly analysing and comparing the aforementioned rectifiers. 相似文献
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Bryant B. Kazimierczuk M.K. 《IEEE transactions on circuits and systems. I, Regular papers》2006,53(1):99-105
A new transfer function from control voltage to duty cycle, the closed-current loop, which captures the natural sampling effect is used to design a controller for the voltage-loop of a pulsewidth modulated (PWM) dc-dc converter operating in continuous-conduction mode (CCM) with peak current-mode control (PCM). This paper derives the voltage loop gain and the closed-loop transfer function from reference voltage to output voltage. The closed-loop transfer function from the input voltage to the output voltage, or the closed-loop audio-susceptibility is derived. The closed-loop transfer function from output current to output voltage, or the closed loop output impedance is also derived. The derivation is performed using an averaged small-signal model of the example boost converter for CCM. Experimental verification is presented. The theoretical and experimental results were in good agreement, confirming the validity of the transfer functions derived. 相似文献
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Sebastian J. Martinez J.A. Alonso J.M. Cobos J.A. 《Power Electronics, IEEE Transactions on》1998,13(4):727-738
In this paper, we propose to study the use of several zero-current-switched (ZCS) quasi-resonant converters (QRCs) (buck-boost, flyback, SEPIC, Cuk, boost, and buck) with a half-wave switch, working as power factor preregulators (PFPs) with voltage-follower control. The analysis carried out demonstrates that these converters show excellent characteristics to obtain a high power factor (PF) without using any input-current feedback loop, and they also allow high switching frequency to operate because they integrate transformer and rectifier diode parasitics into the power topology 相似文献
6.
The effects of a nonnegligible source impedance, due to the presence of an input EMI filter, on the stability of power factor preregulators (PFPs) with average current control are analyzed by using a state-space averaged model. Different from previous approaches, it allows us to derive a simple expression for the loop gain in terms of the converter current loop gain. The overall system stability was studied for boost, Cuk, and SEPIC PPP topologies. Based on this model, a simple modification of the standard current control loop is proposed which increases the converter robustness against instabilities. Comparison between model forecasts and experimental measurements was carried out using two prototypes, one based on the boost topology and the other based on the SEPIC topology, both rated at 600 W. Finally, the model accuracy was investigated with measurements at different current loop bandwidths 相似文献
7.
Active clamp topologies of low power dissipation have become a very attractive solution in order to limit overvoltages in flyback converters. Although many suitable topologies have been introduced for the case of discontinuous conduction mode (DCM), where the duty cycle value depends on the load level, in continuous conduction mode (CCM) it is more difficult to appropriately design such topologies so as to "sense" load changes-due to the small duty cycle divergence under wide load variation. Taking for granted that in order to achieve high power-factor correction in these converters, CCM is a more attractive mode of operation, a drastic solution for this case that will manage to eliminate voltage stresses under wide load changes has become very essential. For this purpose, this paper presents an active clamp topology with small power dissipation, suitable for flyback converters operating in CCM mode. Its main idea is the use of a load-dependent current source, consisting of an auxiliary converter operating in DCM mode. Experimental results highlight the effectiveness of the proposed topology under wide load changes, establishing it as an appropriate solution in order to develop flyback converters, even at the power range of 500 W. 相似文献
8.
An analytical procedure to optimize the feedforward compensation for any PWM DC/DC power converters is described. Achieving zero DC audiosusceptibility was found to be possible for the buck, buck-boost, Cuk, and SEPIC cells; for the boost converter, however, only nonoptimal compensation is feasible. Rules for the design of PWM controllers and procedures for the evaluation of the hardware-introduced errors are discussed. A PWM controller implementing the optimal feedforward compensation for buck-boost, Cuk, and SEPIC cells is described and fully experimentally characterized 相似文献
9.
Bryant B. Kazimierczuk M.K. 《IEEE transactions on circuits and systems. I, Regular papers》2005,52(10):2158-2164
This paper presents the analysis of open-loop power-stage dynamics relevant to current-mode control for a boost pulsewidth-modulated (PWM) dc-dc converter operating in continuous-conduction mode (CCM). The transfer functions from input voltage to inductor current, from duty cycle to inductor current, and from output current to inductor current are derived. The delay from the MOSFET gate drive to the duty cycle is modeled using a first-order Pade/spl acute/ approximation. The derivations are performed using an averaged linear small-signal circuit model of the boost converter for CCM. The transfer functions can be used in modeling the complete boost PWM converter when current-mode control is used. The theory was in excellent agreement with the experimental results, enforcing the validity of the transfer functions derived. 相似文献
10.
In this paper, nonlinear-carrier (NLC) control is proposed for high-power-factor rectifiers based on flyback, Cuk, Sepic, and other up-down power converters operated in the continuous conduction mode (CCM). In the NLC controller, the switch duty ratio is determined by comparing a signal proportional to the integral of the switch current with a periodic nonlinear-carrier waveform. The shape of the NLC waveform is determined so that the resulting input-line current follows the input-line voltage, as required for unity power factor rectification. A simple exponential carrier waveform generator is described. Using the NLC controller, input-line voltage sensing, error amplifier in the current-shaping loop, and multiplier/divider circuitry in the voltage feedback loop are eliminated. The simple high-performance controller is well suited for integrated-circuit implementation, Results of experimental verification on a 150 W flyback rectifier are presented 相似文献
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A mixed-mode input current sensorless predictive current control at constant but two different switching frequencies for a single-phase boost type switch-mode rectifier (SMR) with single switch topology is proposed. The SMR operates in continuous input current mode (CCM) or in discontinuous input current mode (DCM) depending upon the load. This load dependent operating mode selection avoids the operation of the SMR in the dual mode, where the input current harmonic distortion is maximum. The closed loop output voltage regulation is achieved without the need of an input current sensor. The control scheme is optimized to result in an economic size of the boost inductor along with the compliance of IEC 1000-3-2 harmonic limits for input current. 相似文献
14.
《Power Electronics, IEEE Transactions on》2009,24(9):2120-2126
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Single-phase Z-source PWM AC-AC converters 总被引:1,自引:0,他引:1
The letter proposes a new family of simple topologies of single-phase PWM ac-ac converters with a minimal number of switches: voltage-fed Z-source converter and current-fed Z-source converter. By PWM duty-ratio control, they become "solid-state transformers" with a continuously variable turns ratio. All the proposed ac-ac converters in this paper employ only two switches. Compared to the existing PWM ac-ac converter circuits, they have unique features: providing a larger range of output ac voltage with buck-boost, reversing or maintaining phase angle, reducing in-rush and harmonic current, and improving reliability. The operating principle and control method of the proposed topologies are presented. Analysis, simulation, and experimental results are given using the voltage-fed Z-source ac-ac converter as an example. The analysis can be easily extended to other converters of the proposed family. The proposed converters could be used in voltage regulation, power regulation, and so on. 相似文献
16.
在 Ridley 峰值电流模式控制的 Buck 变换器模型的基础上,提出一个包含传导损耗的修正模型.运用平均开关建模法,建立非理想PWM开关的非线性大信号平均模型.包含全部寄生电阻和二极管的正向压降.围绕某一稳态工作点,扰动并线性化平均模型,导出非理想Buck变换器的功率级在连续工作模式下的直流模型和线性小信号模型.在此基础上.修正峰值电流模式控制部分的小信号模型参数.最终建立整个峰值电流模式控制的非理想Buck变换器的线性小信号模型.推导小信号动态的解析结果.给出修正的补偿斜坡信号斜率.在Simetrix/simplis开关电源软件包中进行了仿真分析,结果显示新模型能更准确地预测系统性能. 相似文献
17.
A three-phase rectifier employing three single-phase boost power-factor-correction circuits is analyzed. Each converter operates in the continuous conduction mode (CCM), which allows a high power factor and a small EMI filter. Current sharing is ensured by a common voltage loop driving the individual current loops of the three converters. A suitable circuit arrangement is devised to limit phase interaction. The zero-voltage-transition technique (ZVT) is successfully applied to each converter, in order to obtain zero turn on losses and soft turnoff of the freewheeling diodes. Results of a 1800-W 100-kHz experimental prototype are reported, which confirm the theoretical forecasts 相似文献
18.
This paper presents a novel single-phase high-power-factor (HPF) pulsewidth-modulated (PWM) boost rectifier featuring soft commutation of the active switches at zero current (ZC). It incorporates the most desirable properties of conventional PWM and soft-switching resonant techniques. The input current shaping is achieved with average current mode control and continuous inductor current mode. This new PWM power converter provides ZC turn on and turn off of the active switches, and it is suitable for high-power applications employing insulated gate bipolar transistors (IGBTs). The principle of operation, the theoretical analysis, a design example and experimental results from a laboratory prototype rated at 1600 W with 400 VDC output voltage are presented. The measured efficiency and the power factor were 96.2% and 0.99%, respectively, with an input current total harmonic distortion (THD) equal to 3.94%, for an input voltage with THD equal to 3.8%, at rated load 相似文献
19.
This paper presents a novel power factor correction technique for single-phase boost type AC-to-DC converters in continuous conduction mode. Instead of using the inductor current or switching device current, in this paper, the diode current in the boost converter is used to formulate the duty ratio of the switch in a special way which makes the input current sinusoidal and in phase with the input voltage. To improve the dynamic performance and minimize the input current harmonic components, a new double-injection compensation method is employed in the voltage feedback loop. The power factor corrector has the following advantages: (1) operation with constant switching frequency; (2) elimination of input voltage sensing, error amplifier in the current loop and multiplier in the output voltage feedback loop; (3) minimal total harmonic distortion in the input current; (4) fast dynamic response of the output voltage loop; and (5) simple implementation of the control circuit. The principles of operation of the proposed control scheme are explained. Simulation and experimental results are presented to verify the feasibility of the control strategy 相似文献
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几种新型的Buck—Boost变换器的合成 总被引:1,自引:0,他引:1
从传输机制说明单管升降压变换器(如Buck-Boost、SPEIC、Cuk)中元件承受的电压和电流应力高的原因,并根据这一机制,采用变换器合成的方式,提出了一系列的双管Buck-Boost变换器。这类变换器根据输入输出条件,可以分别工作于Boost模式和Buck模式,起到降低元件应力的作用。 相似文献