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1.
基于Boost变换器,介绍了一种新的控制方法一电流模式模糊控制。这种新的控制方法属于双环控制,外环由模糊控制器构成,内环是电流环。该控制方法不同于传统的以模糊控制器作控制环路的单环控制。这种新的控制方法结合了传统的模糊控制和电流模式控制的优点,能改善变换器系统的性能。本文建立了电流模式模糊控制的Boost变换器的小信号模型,推导了传递函数。在Matlab/Simulink环境下,做了基于传递函数的仿真和基于电路模块的仿真。仿真结果显示基于传递函数的仿真和基于电路模块的仿真结果一致,证实了本文所建立模型的正确性。  相似文献   

2.
基于电感和电容本质上是分数阶的事实,基于分数阶微积分理论结合改进的Oustaloup分数阶微积分滤波器近似算法,在Matlab/Simulink下建立了电流连续模式下的电压控制型Buck变换器的分数阶数学仿真模型和对应的电路仿真模型,通过仿真验证了该模型的正确性。基于建立的分数阶数学仿真模型研究了很少有文献研究的以参考电压和比例放大系数作为混沌控制变量的Buck变换器的混沌行为,得到了分别以参考电压、比例放大系数为变量的Buck变换器的V-I混沌相图。此模型可以对电压控制型Buck变换器的所有能导致混沌行为的7种情况进行仿真分析,利用此模型仿真分析了Buck变换器的阶数对系统动态响应过程的影响。该模型的建立方法也适用于其他DC/DC变换器的分数阶模型的建立。  相似文献   

3.
半桥三电平变换器拓扑解决了PFC技术带来的功率管应力过高问题,非常适合于大功率高压输出场合,峰值电流模式采用电压外环,电流内环的双环控制,是开关电源闭环系统最实用的控制模式.对移相半桥三电平DC/DC变换器进行了小信号建模分析;建立了峰值电流内环和电压外环的小信号传递函数,在此基础上给出了峰值电流模式的移相半桥三电平变换器闭环系统结构图,推导出相关闭环传递函数;给出了补偿网络参数设计步骤;对建立的双闭环系统模型进行了MATLAB仿真,结果表明经过补偿后的闭环系统具有满意的性能指标.  相似文献   

4.
0616992一种大负载和变电压输入条件下大功率DC/DC变换器的新型控制策略〔刊,中〕/Seyed Reza Hadian Am-rei//电网技术.—2006,30(6).—53-58(L)由于DC/DC开关变换器具有许多优良的特性,近年来得到了许多应用。基于变结构控制的滑模控制方式可被应用于各种开关变换器的控制,电流模式控制方式只是特定地应用于DC/DC变换器的控制。然而,在大负载电流和输入电压波动的情况下,这些控制方式的补偿能力明显不足。文章综合这两种控制策略提出了一种新的控制策略和获得动态参考电流的方法,并进行了仿真分析。结果证明,这种动态参考电流的获…  相似文献   

5.
Boost变换器的开环传递函数有一个位于右半平面的零点,使得使用单一的反馈电压环难以同时保证系统在受到某种扰动作用时,既有很好的动态品质又不致造成系统失稳。平均电流控制模式是提高Boost变换器稳定性和动态调节特性的有效方法。分析并推导了Boost变换器的平均电流控制模型,应用saber对系统的分析和仿真,其结果证明了所建模型的正确。  相似文献   

6.
李洋  李莉 《现代电子技术》2014,(16):144-147,151
提出采用三端PWM开关模型法建立PS-FB-ZVS-PWM变换器的平均电路小信号模型。分析并推导出PS-FBZVS-PWM变换器的传递函数,设计了电流内环功率外环的双环控制算法,并分析了基于双环控制的开环传递函数幅频和相频特性,最后通过PSIM仿真软件搭建了变换器的仿真模型。实验结果验证了基于双环控制的PS-FB-ZVS-PWM变换器可以很好地实现对输出功率的控制。  相似文献   

7.
多模式AC/DC控制芯片根据负载情况选定相应高效的工作模式以获得高效率.为了合理设定工作负载,在基于Verilog-A建立的反激式变换器仿真模型基础上,仿真研究了多模式AC/DC控制芯片的过载行为.结果表明,当负载过重后,变压器初级获得的能量不足以使输出电压稳定,输出电压开始下降.根据仿真曲线确定了输出电压20 V下的过载点为13.4 Ω.  相似文献   

8.
基于电感与电容的分数阶事实,在Matlab/Simulink下建立了电压控制型Buck变换器的分数阶数学仿真模型及对应的电路仿真模型,分析验证了模型的正确性。基于建立的分数阶数学仿真模型,少有文献研究的以参考电压作为混沌控制变量的Buck变换器混沌行为,绘制了以参考电压为混沌变量的Buck变换器V-I混沌相图与对应的分岔图,得出较小的参考电压易引起Buck变换器进入混沌状态。最后,采用参数扰动法实现了混沌控制,得到了新的分岔图,与混沌控制前的分岔图形成了鲜明的对比。同时,通过选定特定的参考电压值,经分析混沌控制前后电感电流的时域波形图,验证了该控制算法的有效性。  相似文献   

9.
对DC/DC变换器进行仿真,可更好地指导和改进实际电路的设计调试。但现有仿真软件无闭环仿真模型,针对DC/DC变换器设计很难进行闭环仿真这一问题,文中利用MATLAB软件的Simulink工具箱,结合电路特点,给出环路传递函数,搭建了电路闭环仿真模型,模拟了BUCK电路的PID环路控制,实现了DC/DC变换器的PID闭环仿真,为DC/DC变换器的研究与应用提供了理想的工具。同时基于BUCK电路编写了BUCK电路参数的MATLAB设计程序,简化了变换器设计过程。  相似文献   

10.
刘晓悦 《电子器件》2021,44(1):46-51
本文介绍了一种新的高功率双向隔离式DC/DC变换器。DC/DC转换器使用基于氮化镓(GaN)的功率开关器件。本文对10 kW GaN大功率DC/DC变换器的拓扑结构进行了优化,参数化和分析,并通过仿真和验证了其有效性。它由两个单相全桥电路、两个输入输出电感和一个高频变压器组成。高频变压器在实现两个全桥变换器之间的电流隔离方面起着至关重要的作用。使用MATLAB仿真软件对10 kW的变换器进行了建模。MATLAB仿真结果验证了变换器的性能适合于高功率应用并能实现轻负载条件下的零电压开通(ZVS)和零电流关断(ZCS)。然后,设计了一个7 kW的实验原型,以验证所设计拓扑的有效性。  相似文献   

11.
The bottleneck of digital control for power factor correction (PFC) implementations is mainly due to three aspects: high calculation requirements, high cost, and limited switching frequency compared with analog implementations. A new duty cycle control strategy for boost PFC implementations is proposed in this paper. The duty cycle is determined based on the input voltage, reference output voltage, inductor current, and reference current. The duty cycle determination algorithm includes two terms, the current term and the voltage term, which can be calculated in parallel and requires only one multiplication and three additions (subtractions) operations in digital implementation. A 400-kHz switching frequency boost PFC based on field programmable gate array implementation and its test results show that the proposed new duty cycle control strategy has great potential in the next generation of high switching frequency PFC implementations, due to its lower calculation requirement, lower cost, and better performance than the conventional PFC control methods  相似文献   

12.
本文提出了一种适用于低压大电流输出场合的软开关移相全桥变流器。该变流器原边带有储能电感,副边采用同步整流技术,通过合理的设计能够使之工作于断续模式(DCM)。其中原边储能电感可以简单方便地实现超前臂开关管的零电压开通。这种工作模式不但能够实现滞后臂的零电流关断,还能实现副边整流器件的零电流关断,有效地降低其开关损耗、体二极管的反向恢复损耗以及抑制寄生结电容电压震荡尖刺等。又因为副边同步整流管的电压应力受到输出电压箝位,所以可以选用较低耐压的同步整流管降低副边的导通损耗。最后根据理论分析设计研制了一台工作频率100kHz,额定功率300Watts的实验样机验证了它的基本工作原理,而其较高的变换效率也体现了该移相全桥变流器的优点。  相似文献   

13.
A novel voltage sensorless control technique for a bidirectional AC/DC converter is presented. Only a single current sensor that measures the inductor current is needed in the whole system. The sensed inductor current is used for two functions. The first one is for shaping the current waveform at the AC side and the second one is for deriving the inductor voltage by determining the rate of change of the inductor current. The AC-side and DC-side voltages, which are used for AC current synchronization and DC voltage regulation, respectively, are obtained by extracting the envelopes of the derived inductor voltage. Apart from reducing the number of sensing elements, the proposed method has additional advantages of: (1) inherent electrical isolation and reducing noise coupling between the power circuit and the controller; (2) wide operating range. Design criteria for the differentiator and the envelope detector circuit has been described. The applicability of the proposed method is verified with the experimental results of a laboratory prototype.  相似文献   

14.
刘树林  刘健  钟久明 《电子学报》2007,35(5):838-843
根据电感电流最小值与输出电流的比较,将Buck-Boost 变换器的能量传输模式(ETM)分为完全电感供能模式(CISM)和不完全电感供能模式(IISM),得出了CISM和IISM的临界条件和临界电感.将电感电流最小值与零和输出电流进行比较,得出Buck-Boost 变换器存在三种工作模式,即CISM、不完全电感供能且连续导电模式(IISM-CCM)和不完全电感供能且不连续导电模式(IISM-DCM).推导出了变换器工作于三种模式时的输出纹波电压表示式,指出对于给定负载、电容和开关频率的Buck-Boost变换器,CISM的输出纹波电压最小且与电感无关,而IISM-CCM和IISM-DCM的输出纹波电压较大且随电感减小而增大.CISM和IISM的临界电感即为使得变换器的输出纹波电压最低的最小电感.文中给出实例,实验结果与理论分析一致,但因未考虑器件参数输出纹波电压略高于理论分析值,实验结果验证了理论分析的正确性.  相似文献   

15.
通过对Boost型变换器在不连续导电模式DCM(Discontinued Conduction Mode)下平均电感电流的分析,得到了在恒 频状态下实现功率因数校正 PFC ( Power Factor Correction)时,功率开关管所需的开启时间与输入、输出电压之间的数学关系,并结合实际电路设计,提出了一种PF...  相似文献   

16.
A unified constant-frequency integration (UCI) controller for a three-phase star-connected switch three-level rectifier (VIENNA) with unity-power-factor-correction is proposed. One of advantages of this rectifier is that the switch voltage stress is one half of the total output voltage. The proposed control approach is based on one-cycle control and features great simplicity and reliability: all three phases will be power factor corrected using one or two integrators with reset along with several flips-flops, comparators and logic and linear components. It does not require multipliers to scale the current reference according to the output power level as used in many other control approaches. In addition, the input voltage sensor is eliminated. It employs constant switching frequency modulation that is desirable for industrial applications. The proposed controller can operate by sensing either the inductor currents or the switching currents. If the switching currents are sensed, the cost is further reduced because switching currents are easier to sense comparing with inductor currents. The proposed approach is supported by experimental results.  相似文献   

17.
A novel current mode control scheme for the tristate boost converter circuit is proposed, which eliminates the zero in the right-half plane (RHP), and improves the dynamic performance. The tristate boost converter contains an additional switch across the inductor. Within a clock cycle, the inductor current first rises during the on interval of the main switch, then falls during the off or capacitor charging interval, and finally, remains almost constant during the freewheeling interval when the additional switch is turned on. In the proposed controller, the peak value of the inductor current is controlled by peak current mode control using an outer voltage feedback loop, whereas the freewheeling current is controlled by the input voltage and the reference voltage feedforward path. Applying both feedback as well as feedforward control on the inductor current significantly improves the output voltage regulation, audio susceptibility, and transient responses. We show that the RHP zero is completely eliminated from the closed-loop control-to-output transfer function. This results in a very large bandwidth, and hence a superior dynamic performance. The latter is established by comparison with the voltage-mode- and current-mode-controlled classical boost converters that suffer from the RHP zero problem, as well as with other tristate boost converter control techniques like the constant charging interval and dual mode control, recently proposed in the literature. Significant superiority of the proposed scheme is established both through simulation and experimentation.  相似文献   

18.
张麟  吴金 《电子器件》2004,27(2):329-333
多输出是DC-DC电路发展的一个重要趋势。在分析常规的多输出DC-DC结构及其工作原理基础上,系统研究了SIMO结构,该结构只使用一个电感,以各输出支路分时工作实现多输出。但由于电感共享,输出支路之间存在严重的交叉影响。若输出支路严格工作于DCM/PCCM模式下,可抑制这种交叉影响。在此基础上,提出了一个新的控制方式,在没有交叉影响CCM模式下实现SIMO工作。  相似文献   

19.
This paper presents the realization of a boost-type active power factor corrector (APFC) using a single current sensor to sense the inductor current for input current shaping and output voltage regulation. Neither input voltage nor output voltage sensing is needed. The sensed inductor current is used for two main functions. The first one is for comparing with a sawtooth signal in order to shape the input current waveform. The second one is for determining the input and output voltages by processing the rate of change of the inductor current when the main switch is in on and off states, respectively. Compared with conventional APFCs, the proposed technique has several advantages. First, no dissipative voltage divider is required. Second, electrical isolation between the power conversion stage and the control stage can be achieved inherently. Finally, no complicated or sophisticated digital sampling and numerical computations are needed. The applicability and accuracy of the proposed technique have been studied experimentally. Steady-state behavior and large-signal response under output load disturbance are also investigated.  相似文献   

20.
本文将单周控制的矢量模式应用于有源电力滤波器,对其进行了理论分析和仿真研究,单周控制矢量模式的有源电力滤波器不需要任何乘法器,不需要检测负载电流,只需检测电源电流和电源电压过零点,而且不需计算APF电感电流的参考值。因此可以省略复杂的计算;工作于高频的开关数量也相对减少了,从而降低了开关损耗;它对负载的依赖性不强,可以适用于不同的负载。另外,用PSIM软件对该控制方法进行了建模仿真。仿真结果验证了理论分析的正确性。  相似文献   

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