Boost变换器的滑模变结构控制方法研究

本文提出了一种Boost变换器的滑模变结构控制方法。这种方法基于Boost变换器的开关模型。在控制器中引入滞环环节，使系统可以获得固定的开关频率，并分析了开关频率与滞环宽度的关系，给出了控制器参数的渊节方法。所设计的控制器响应速度快，对负载变化和电压波动鲁棒性强，易于实现。     

模块化多电平换流器电容电压的滑模观测器研究

模块化多电平换流器（modular multilevel converter,MMC）子模块电容电压的稳压控制是MMC的一个关键难题,在实际应用中,需要大量的电压传感器以获取各子模块电容电压。对此提出了一种电容电压滑模观测器（sliding mode observer,SMO）,根据MMC电路中的桥臂电流和开关信号观测出子模块电容电压,并结合电压闭环控制,实现电容电压的稳定,采用双曲正切函数tanh作该滑模观测器的切换函数,可削弱系统抖振。仿真和实验结果表明该滑模观测器可准确观测出电容电压。     

Boost变换器跨周期调制(PSM)的状态空间平均模型

基于Boost变换器,利用状态空间平均法对跨周调制(Pulse Skipping Modulation,PSM)进行建模和特性分析,推导出电感电流连续(CCM)和电感电流断续(DCM)时系统变压比,调制度M与负载的关系及系统转换效率的理想化公式,得到PSM具有轻载下高转换效率的结论,并设计具有PSM调制特性的控制电路,给出仿真结果。     

滑模控制开关变换器的分析与实现

分析了滑模控制DC／DC变换器的滑模存在条件、到达条件及稳定性，通过选择适当的状态变量，建立系统状态方程模型。提出了一种实用性较强的双环控制方案，并以Buck电路为例，设计出滑模控制电路。实验结果表明，此控制方案是可行的，它可以有效地改善变换器的动态性能，提高其鲁棒性。     

开关电源Boost变换器输出纹波的仿真研究

文章在分析典型DC-DC变换拓扑结构的基础上,建立了降压型（Boost）DC-DC变换器的PSpice仿真模型。在三种工作模式下,针对输入电压、电感和负载电阻对输出电压纹波都有不同程度的影响,对Boost变换器输出纹波电压的影响因素进行了分析。其结论为Boost型DC-DC变换器的设计和研制提供了理论依据。     

Design and Application for PV Generation System Using a Soft-Switching Boost Converter With SARC

In order to improve the efficiency of energy conversion for a photovoltaic (PV) system, a soft-switching boost converter using a simple auxiliary resonant circuit, which is composed of an auxiliary switch, a diode, a resonant inductor, and a resonant capacitor, is adopted in this paper. The conventional boost converter decreases the efficiency because of hard switching, which generates losses when the switches are turned on/off. During this interval, all switches in the adopted circuit perform zero-current switching by the resonant inductor at turn-on, and zero-voltage switching by the resonant capacitor at turn-off. This switching pattern can reduce the switching losses, voltage and current stress of the switching device. Moreover, it is very easy to control. In this paper, we have analyzed the operational principles of the adopted soft-switching boost converter, and it is designed for PV generation system. Simulation and experimental results are presented to confirm the theoretical analysis.      

Fuzzy Switching Technique Applied to PWM Boost Converter Operating in Mixed Conduction Mode for PV Systems

Due to the variation of the maximum power point (MPP) of photovoltaic (PV) generators with solar radiation and temperature, boost DC-DC converters placed between PV modules and inverters in grid-connected PV systems have to be controlled in a variable operating-point condition. In addition, inductor current dynamics changes suddenly when moving from continuous to discontinuous conduction mode. The previous difficulties make the design of reliable and fast control laws for the input voltage of boost converters complicated. The aim of this paper is to propose a control algorithm based on cascaded-loop control. The input voltage is controlled by the outer loop. The inductor current is controlled by an inner loop strategy which is able to perform in mixed conduction mode, owing to the fuzzy switching technique. Simulation and experimental results for a 10-kW boost converter show that the proposed strategy achieves an accurate and robust performance at every operating point, even if the inductor value varies in a wide range; thus, fast MPP tracking techniques can be implemented. An additional advantage is that constant switching frequency is achieved.     

基于积分滑模和ESO的四旋翼无人机容错控制

针对四旋翼无人机桨叶损伤故障的位置和姿态控制问题,设计一种基于积分滑模法和扩张状态观测器(ESO)的四旋翼无人机主动容错控制系统.建立了执行机构损伤故障下的无人机非线性模型,采用抗干扰能力较强的滑模控制法(SMC)设计姿态内环和位置外环基本控制器;为减小系统的稳态误差,引入积分环节,构造出积分滑模控制器;通过采用边界层...     

电流控制模式开关变换器研究

文章对开关变换器的电流型反馈控制模式的基本原理、斜坡补偿的效果以及控制电路特点进行了讨论,分析了其优缺点。对电流型控制模式的不足之处,通过分析给出了解决办法。最后给出不同应用电路反馈控制类型的选取原则。     

峰值电流模式非理想Boost变换器建模

应用能量守恒法建立了非理想Boost变换器的小信号模型,在该电路拓扑结构的基础上引入了峰值电流模式控制,并进一步推导出含有斜坡补偿的情况下电路等效功率级的精确模型,该模型具有更高的精度;然后以峰值电流模式Boost变换器为基础,针对该电路存在的缺点设计了电压控制器补偿网络,使得补偿后的系统具有更好的稳定性,并通过MATLAB软件仿真验证了该方案的优点和利用价值.     

Analysis of a Zero-Voltage Switching Converter With Two Transformers

This brief presents an active-clamp zero-voltage switching converter. Two transformers connected in series are used, and each transformer can be operated as an inductor or a transformer. No output inductor is needed. An active-clamp circuit is used to recycle the energy stored in the transformer leakage. The system analysis, operation principles, and design equations of the proposed converter are provided. Experiments based on a laboratory prototype are also provided to confirm the converter performance     

High-Gain Observers With Sliding Mode for State and Unknown Input Estimations

To handle the state estimation of a nonlinear system perturbed by a scalar disturbance distributed by a known nonlinear vector, a sliding-mode term is incorporated into the nonlinear high-gain observer (HGO) to realize a robust HGO. By imposing a structural assumption on the unknown input distribution vector, the observability of the disturbance with respect to the output is safeguarded, and the disturbance can be estimated from the sliding surface. Under a Lipschitz condition for the nonlinear part, the nonlinear observers are designed under the structural assumption that the system is observable with respect to any input. In the sliding mode, the disturbance under an equivalent control becomes an increment of Lipschitzian function, and the convergence of the estimation error dynamics can be proven similar to the analysis of HGOs. The proposed technique can be applied for fault detection and isolation. The simulation results for the bioreactor application demonstrate the effectiveness of the proposed method.      

A Three-Level Full-Bridge Zero-Voltage Zero-Current Switching Converter With a Simplified Switching Scheme

Multilevel dc–dc converters making use of high-frequency transformers are suitable for integration in solid-state solutions for applications in electric power distribution systems. This paper presents a simplified switching scheme for three-level full-bridge dc–dc converters that enables zero-voltage and zero-current switching of all the main power devices. It describes the main operational modes and design equations of the converter as well as provides simulation and experimental results to demonstrate the feasibility of the proposed ideas.      

A 120-W Boost Converter Operation Using a High-Voltage GaN-HEMT

A boost converter with a 940-V/4.4 A GaN-HEMT as the main switching device was demonstrated to show the possibility of using high-voltage GaN-HEMTs in power electronic applications. The demonstrated circuit achieved an output power of 122 W and a power efficiency of 94.2% under a drain peak voltage as high as 350 V and a switching frequency of 1 MHz. The dual field-plate structure realized high-voltage switching operation with high power efficiency as dynamic on-resistance was suppressed by an increase of the current collapse phenomena.     

混合网络下双模ONU切换设计

随着三网融合、“光进铜退”国家政策推行和用户固网带宽需求增长,以EPON、GPON为代表的无源接入技术成为应用热点.国内PON网络以EPON、GPON共存,本文对E/GPON双模ONU做了研究,提出双模ONU的设计方案,市场应用前景广泛.     

临界导通模式Boost功率因素校正变换器电感的设计

介绍了脉动输入电压下Boost PFC变换器电感的设计方法,推导了临界导通模式电感的数学式。用NCP1608芯片设计了一款LED路灯电源的Boost PFC变换器。实验表明,在100V~240V交流输入电压范围内,PFC变换器效率大于96%,功率因数大于0.96,证实了电感数学式的正确性。     

基于滑模控制的双向直流变换器研究

针对光伏电池本身的局限性,需要利用蓄电池来辅助对负载供电。文中所设计的双向直流变换器主要用于对蓄电池的充放电,以双向直流变换器的状态空间平均模型为基础,设计了一种新型的滑模控制器。通过实验仿真验证了基于该滑模控制器的双向直流变换器在开关管交替导通状态下能有效地减小稳态误差,且输出较稳定,能使系统具有更高的稳定性和更好的瞬时性。     

Boost Converter With Coupled Inductors and Buck–Boost Type of Active Clamp

This paper proposes a boost converter with coupled inductors and a buck-boost type of active clamp. In the converter, the active-clamp circuit is used to eliminate the voltage spike that is induced by the trapped energy in the leakage inductor of the coupled inductors. The active switch in the converter can still sustain a proper duty ratio even under high step-up applications, reducing voltage and current stresses significantly. Moreover, since both main and auxiliary switches can be turned on with zero-voltage switching, switching loss can be reduced, and conversion efficiency therefore can be improved significantly. A 200 W prototype of the proposed boost converter was built, from which experiment results have shown that efficiency can reach as high as 92% and surge can be suppressed effectively. It is relatively feasible for low-input-voltage applications, such as fuel cell and battery power conversion.     

并行电流模式控制Boost变换器的建模与仿真

本文基于BoostDC-DC变换器,提出了一种新的控制方法：并行电流模式控制。在这种颓的控制方法下,占空比由并行的电压项和电流项组成,电压项由参考电压和输入电压决定;电流项由电感电流,参考电流和参考电压决定。该控制方法不同于传统的外环为电压环内环为电流环的双环控制。建立了并行电流模式控制的Boost DC—DC变换器的小信号模型。给出了基于传递函数的Matlab／Simulink仿真模型和在PSIM环境下的电路仿真模型。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。同时仿真结果也表明并行电流模式控制比电压模式控制具有更好的控制特性。     

开关变换器中数字控制设计方法的研究

文中系统地介绍了两种数字控制设计方法:数字重算方法、直接数字方法。数字重算方法又根据离散方法的不同分为四种:反向欧拉法、双直线法、阶跃不变法、极零点匹配法。对各种方法在带宽和控制回路的相补角等方面进行比较,并且研究了各种方法在低采样率下的不同性能,最后根据仿真结果可以得出直接设计方法最适合开关变换器。而在数字重算方法中,反向欧拉法是最适合的离散方法。