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用于电动汽车的多重化软开关双向DC/DC变换器的研究 总被引:1,自引:0,他引:1
针对典型的半桥式双向DC/DC变换器拓扑结构特点,利用DCM模式下电感电流反向的特征,采用一种不额外添加半导体器件的软开关技术,减小开关损耗;采用多重化拓扑结构弥补DCM模式下电压、电流纹波大的缺陷;在控制方式上采用电压电流双闭环形式,将共用电压环的输出作为每个基本单元的给定电流,解决了并联结构的均流问题。 相似文献
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史建伟 《自动化技术与应用》2011,30(5):8-11
本文设计了一种线性自抗扰控制器,直接对DC/DC升压变换器的电感电流实施控制,以抑制系统非最小相位特性时控制性能的影响.在此基础上,外环采用一个PI控制器对输出电压进行控制,并把电压控制器的输出作为内环电感电流控制的参考输入.由于自抗扰控制器则是一种不依赖丁系统模型的控制方法,因此被控系统不但具有良好的动态特性,而且对... 相似文献
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针对脉冲序列控制开关变换器运行在电感电流连续导电模式下存在较大的低频振荡现象,进而影响开关变换器工作性能的问题,提出了一种连续限制性脉冲序列控制方法。以连续限制性脉冲序列控制Buck变换器为例,详细介绍了该控制方法的工作原理,阐述了其抑制开关变换器低频振荡的机理,建立了连续限制性脉冲序列控制Buck变换器在电感电流连续导电模式下的开关映射模型。通过Matlab仿真和样机实验,对比了脉冲序列控制和连续限制性脉冲序列控制下Buck变换器的输出电压和电感电流情况。研究结果表明,与脉冲序列控制方法相比,连续限制性脉冲序列控制方法通过对连续脉冲个数进行限制,有效抑制了开关变换器在电感电流连续导电模式下的低频振荡现象。 相似文献
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电源管理芯片的应用范围十分广泛,发展电源管理芯片对于提高整机性能具有重要意义,对电源管理芯片的选
择与系统的需求直接相关。其中电荷泵电路通过电荷转移方式工作,来达到在无电感元件情况实现一定升压,因此该升
压电路和该款电源管理芯片在应用中很受欢迎。该设计分析的低功耗电荷泵 DC/DC 升压电路是同国外某公司的合作项
目。该电路采用 0.35 μm 标准的 CMOS 工艺制成,输入电压在 2.5 V~5.0 V,且输入电压高于或低于输出电压时,输出
电压都可保持稳定的低纹波输出,并能自动工作于升压或降压模式。该电荷泵电路采用比较升压电路,有效的降低了芯
片功耗,特别在轻负载情况下提高了系统的转换效率。电路还具有软启动、过热保护及过流保护等多重保护功能。仿真
结果均达到预定指标,是设计理论与实践相结合的一次有价值的尝试。 相似文献
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双向DC/DC变换器是指在保持变换器两端的直流电压极性不变的情况下,根据实际需要完成能量双向传输的直流变换器。它在直流不间断电源系统、分布式电站、电动汽车以及太阳能电池阵中有广泛的应用。通过对双向半桥变换器的分析,并将其与蓄电池相结合使用,完成能量的双向传输和电池能量对电网的回馈。由于DC/DC变换器在升降压的过程中产生的严重的非线性问题,在控制方案上,采用模糊PID控制的电压、电流双闭环控制。仿真表明,与传统的PID控制相比,该控制方案有效提高了变换器的鲁棒性,减小输出电压波动,能够实现能量的双向流动。 相似文献
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针对传统ST滑模控制算法在DC–DC变换系统到达段存在快速性和抑制抖振之间的矛盾问题,提出一种三相交错双向DC–DC变换器的模糊高阶滑模(FZST)控制算法.该算法依据李雅普诺夫函数求解出系统稳定需要满足的收敛条件,然后基于当前误差进行模糊逻辑推算,进一步在线调整收敛条件下的滑模面系数,保证对误差项加速抑制的同时完成对静态误差的积分,保留了ST滑模控制的动态性,并抑制系统的抖振.最后对双向DC–DC半桥回路中的电压环和电流内环,进行双FZST滑模控制的仿真与实验验证,结果表明:系统在电压跟随,输入端电压与输出端负载大扰动情况下, FZST滑模控制算法具有较强的鲁棒性,能够改善系统的动态品质,并有效地解决抖振问题. 相似文献
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分析了准Z-源DC-DC变换器在稳态时的工作原理,根据状态空间平均法建立了准Z-源DC-DC网络在电流连续工作模式下(CCM)的交流小信号模型,并对模型进行分析,获得控制至输出的传递函数,实现了输出电压闭环控制。最后建立了实验样机,进行了实验验证。 相似文献
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针对常规DC-DC变换器输出电压调整困难、反馈实现复杂、智能化程度低的问题,提出了一种新型的能够根据用户要求快速改变输出电压的DC-DC变换器,并且能够根据电源输入的电压变化情况实时调整控制参数,实现稳定的电压输出,且输出电压不受输入电压变化的影响。通过对不同负载和电源输入变化的实验验证,该DC-DC变换器具有输出电压稳定精确、纹波率小、反馈快速准确的特点,对于某些对输入电压稳定性要求高的场合有实际应用意义。 相似文献
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We propose a new controller for DC-DC converters based on particle swarm optimization (PSO). This new converter controller uses the PSO optimization method to directly control, by itself, the output voltage of a boost DC-DC converter. In order to validate and qualify the proposed converter controller, we analyzed and implemented some variants of the PSO algorithm, namely the standard PSO and the global local best PSO. The proposed converter controller was then compared with a variant of the classic PI controller with anti-windup, for different operational conditions. The three controllers compared in this work were implemented in the microcontroller TMS320F28027 by using the code composer studio from Texas Instruments. The results show that the proposed controller exhibits better behavior in terms of settling time and overshoot. Unlike most popular DC-DC converter controllers, the proposed controller does not require any sort of optimal parameter determination. 相似文献
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Anbukumar Kavitha Govindarajan Uma 《International Journal of Control, Automation and Systems》2010,8(6):1320-1329
DC-DC converters are widely used in power electronic systems where there is a need for stabilizing a given dc voltage to a
desired value. It has been reported that DC-DC converters exhibit different non-linear phenomena including bifurcations, quasi-periodicity
and chaos under both voltage mode and current mode control schemes. In this work, current mode controlled SEPIC converter
operating in continuous conduction mode is considered and by varying the reference current Iref, the converter exhibits chaos. It has been observed that the system changes from a stable buck-like operation to an unstable
boost-like operation by varying Iref. Bifurcation diagram is plotted for control signal and capacitor voltage with Iref as bifurcation parameter. Resonant parametric perturbation control technique has been applied to suppress chaos. Effects
of phase shift and frequency mismatch are also analyzed. With phase shift, control power required for suppressing chaos has
been reduced. Also intermittent chaotic stages are suppressed with the effect of frequency mismatch at the expense of increasing
control power. The stability analysis in SEPIC converter is performed by means of discrete model and is validated through
the simulated and experimental results. 相似文献
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This paper proposes a new variable-mode control strategy that is applicable for LLC resonant converters operating in a wide input voltage range. This control strategy incorporates advantages from full-bridge LLC resonant converters, half-bridge LLC resonant converters, variable-frequency control mode, and phase-shift control mode. Under this control strategy, different input voltages determine the different operating modes of the circuit. When the input voltage is very low, it works in a full-bridge circuit and variable frequency mode (FB_VF mode). When the input voltage rises to a certain level, it shifts to a full-bridge circuit and phase-shifting control mode (FB_PS mode). When the input voltage further increases, it shifts into a half-bridge circuit and variable frequency mode (HB_VF mode). Such shifts are enabled by the digital signal processor (DSP), which means that no auxiliary circuit is needed, just a modification of the software. From light load to heavy load, the primary MOSFET for the LLC resonant converter can realize zero-voltage switching (ZVS), and the secondary rectifier diode can realize zero-current switching (ZCS). With an LLC resonant converter prototype with a 300 W rated power and a 450 V output voltage, as well as a resonant converter with 20–120 V input voltage, the experiments verified the proposed control strategy. Experimental results showed that under this control strategy, the maximum converter efficiency reaches 95.7% and the range of the input voltage expands threefold. 相似文献
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本文针对直流降压变换器的负载电阻扰动和输入电压变化等系统不确定因素对输出电压的影响,提出了基于降阶扩张状态观测器的滑模控制方法(SMC+RESO).首先设计降阶扩张状态观测器对系统状态,负载电阻扰动和输入电压变化进行估计,然后基于估计值利用滑模控制技术设计控制器,实现对直流降压变换器系统给定电压跟踪的快速性和准确性.值得注意的是,不同于文[1]所提出的基于扩张状态观测器的滑模控制方法(SMC+ESO),本文所提出的方法采用降阶扩张状态观测器,实现简单,且无需电流传感器,减小了实际应用的成本.利用Lyapunov稳定性定理从理论上证明了所设计的控制器可以保证闭环系统的稳定性.仿真和实验结果表明,与已有的基于扩张状态观测器的滑模控制方法相比,所提出的控制方法更好地改善了系统的跟踪性能和对干扰和不确定性的鲁棒性能,且减少了成本,但是牺牲了系统稳态性能. 相似文献
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The output of renewable energy is the power of low voltage and high current rated designs. Due to the output voltage being too low it does not meet the required maximum voltage load requirements. Therefore, in order to meet the high voltage load, the required limit of the power converter (DC-DC) is used to increase the voltage to the maximum. . The DC output voltage from a renewable energy source is given as input to a DC-DC converter, and the output generated from the converter is used to drive a load. KY boost converter is one of the recently developed DC-DC converters to reduce output voltage ripple. It is suitable for operation in equipment to below low ripple conditions. The disadvantage of this converter is that the boost voltage is a very low design parameter. To obtain the desired boosted voltage, and also to reduce the output voltage ripple, an optimized algorithm is used. Compared with the existing Drosophila optimization technology, the proposed Adaptive Vector Reference Control (AVRC) Method has higher convergence characteristics and lower output ripple. The simulation results are verified by MATLAB simulation with hardware results. The hardware is developed using the Xilinx FPGAs SPARTAN 6A controller, which simplifies the XC3S500E development board prototype in addition to providing additional flexibility for further improvements. The results clearly show improved performance and validate the model. 相似文献
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提出一种应用于电压反馈PWM降压DC-DC开关电源的高性能误差放大器。该放大器采用反馈结构,具有较大的动态范围,并可消除噪声影响,从而显著减小了DC-DC开关电源的纹波电压。文中提出的误差放大器电路采用Chart.35m标准CMOS模拟电路工艺库实现,仿真结果表明,该DC-DC变换器的稳定性较好,系统的转换效率达到80%以上,输出纹波电压的峰-峰值小于20mV。 相似文献