全桥变换器双闭环控制研究

文章根据一种实际应用全桥软开关变换器电源,对其进行小信号分析,设计出双闭环控制系统。在saber专业仿真平台下,建立了移相控制的全桥软开关变换器模型,进行了大量的仿真,验证了设计的可靠性和可行型。     

移相全桥鲁棒性变增益控制策略的研究

针对传统PID控制的移相全桥变换器难以获得理想的动静态特性,在分析移相全桥模型的基础上,设计以输入电压和负载作为变参数的线性变参数模型。利用变参数极值组合将其变为多胞形模型,并通过对其顶点进行稳定性分析和控制器设计,得到一种建立在软开关移相全桥变换器的多胞形线性变参数模型基础上的鲁棒性变增益调度控制。通过Matlab仿真与传统的PID控制进行比较,表明鲁棒性变增益控制器具有更好的控制效果。     

基于基波分析法的全桥LLC变换器建模与仿真

本文分析了全桥LLC谐振变换器的原理,基于基波分析法建立了稳态模型并写出了变换器的直流增益传递函数,使用Mathcad画出了不同情况下的直流增益曲线,并对其进行了特性分析,最后使用saber仿真软件对LLC谐振变换器进行了仿真分析,通过仿真验证了建模的正确性。     

移相全桥变换器的极点配置及自适应预测控制

首先提出了移相全桥ZVS DC/DC变换器一种新的模型——准线性模型，并在此基础上运用带预测环节的极点配置自适应控制设计其数字控制系统，然后在两种测试系统动态响应的条件下，对采用预测环节的极点配置自适应数字控制的移相全桥变换器应用Matlab进行仿真，并与无预测环节的控制情况做了比较。结果表明采用新提出的控制策略不仅补偿了数字控制的时延，保证了上述变换器在各种变化的工作点获得良好的动态响应和稳定性，而且具有控制算法简单和控制过程易于实现的优点。     

移相全桥变换器的建模与仿真

文章通过Buck变换器推导出移相全桥变换器的小信号电路模型,利用解析理论的方法求得变换器运行特性的解析表达式,使之成为能对变换器进行定性和定量分析的建模方法。建模过程中需要做出某些近似假设,以求简化分析。并采用MATLAB软件进行仿真,利用奈奎斯特判据来判断系统的稳定性。     

复合谐振型双向全桥DC/DC变换器

针对传统的谐振型双向全桥DC/DC变换器在能量反向推送时开关管的电流应力激增的缺点,提出了一种新型的LCL复合谐振型双向全桥DC/DC变换器,保证了能量正反向推送时开关管的电流应力均保持较低水平。阐述了谐振变换器的工作原理,建立了变换器的交流阻抗模型,在此基础上给出了变换器的参数设计方法,并通过能量注入及自由振荡控制策略实现了变换器的输出控制。通过实验结果验证了该控制策略的可行性。     

双向全桥DC-DC变换器故障智能检测系统设计

传统DC-DC变换器故障检测系统只对变换器中某重要元器件进行故障检测,导致检测结果不准确。为此,设计了新的双向全桥DC-DC变换器故障智能检测系统。通过闭环霍尔电流传感器对电流信号进行采集,给出信号采集电路,通过分析双向全桥DC-DC变换器元件衰减过程提取故障数据,对不同故障状态样本进行采集,构建HMM模型,求出HMM模型初始参数,迭代参数直至其收敛到既定区间,对采集的电压、电流信号进行归一化处理,产生观察值序列,把观察值序列输入到训练完成的不同HMM模型中,求出相似或然率和相似或然率最大值相应的HMM模型,即为双向全桥DC-DC变换器故障检测结果。实验结果表明所设计系统检测准确性高。     

混合动力船舶双向DC-DC变换器的研究与设计

针对全桥双向DC-DC变换器Buck和Boost两种模式参数设计要求不同的问题,提出了一种"占空比-变压器-电感"匹配设计法。对全桥双向DC-DC变换器的两种工作模式分别进行建模,设计了闭环控制系统,Buck模式的闭环控制系统保证了动力电池恒压充电;Boost模式的闭环控制系统保证了母线电压恒定。根据混合动力船舶的特点设计了双向DCDC变换器,仿真实验验证了所设计的双向DC-DC变换器控制系统和控制策略的正确性,保证了分别处于两种工作模式时输出端电压稳定。     

一种基于GaN器件大功率双向DC/DC变换器

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。     

专家系统PID在ZVZCS变换器中的应用

对移相全桥零电压零电流开关(Zero-Voltage and Zero-Current Switch,ZVZCS)变换器数学模型进行深入分析,提出用专家系统PID控制器实现对变换器开关管导通相序和占空比的改变。详细介绍了移相全桥ZVZCS变换器的拓扑结构、工作模态、小信号模型推导以及专家系统PID的设计规则,最后用Simulink仿真验证了算法的正确性和可行性,并对结果进行了分析讨论。     

A PWM plus phase-shift control bidirectional DC-DC converter

A pulse-width modulation (PWM) plus phase-shift control bidirectional dc-dc converter is proposed. In this converter, PWM control and phase-shift control are combined to reduce current stress and conduction losses, and to expand ZVS range. The operation principle and analysis of the converter are explained, and ZVS condition is derived. A prototype of PWM plus phase-shift bidirectional dc-dc converter is built to verify the analysis.     

A zero-voltage and zero-current switching three-level DC/DC converter

This paper presents a novel zero-voltage and zero-current switching (ZVZCS) three-level DC/DC converter. This converter overcomes the drawbacks presented by the conventional zero-voltage switching (ZVS) three-level converter, such as high circulating energy, severe parasitic ringing on the rectifier diodes, and limited ZVS load range for the inner switches. The converter presented in this paper uses a phase-shift control with a flying capacitor in the primary side to achieve ZVS for the outer switches. Additionally, the converter uses an auxiliary circuit to reset the primary current during the freewheeling stage to achieve zero-current switching (ZCS) for the inner switches. The principle of operation and the DC characteristics of the new converter are analyzed and verified on a 6 kW, 100 kHz experimental prototype.     

A high-performance ZVS full-bridge DC-DC 0-50-V/0-10-A power supplywith phase-shift control

This paper presents a high-performance DC-DC switching mode power supply designed to deliver a regulated 0-50 V/0-10 A output. The proposed power supply is based on a modified version of the zero-voltage switching (ZVS) full-bridge (FB) phase-shift DC-DC converter, which incorporates commutation auxiliary inductors to provide ZVS for the entire load range as well as a commutation aid circuit to clamp the output diode voltage. The control strategy is based on two control loops operating in cascade mode. The inner loop maintains a regulated output current, whereas the external voltage loop regulates the output voltage, independently of load and input-voltage changes. In order to obtain a high-reliability converter, the control circuit has been implemented using just two integrated circuits (ICs). The phase-shift regulator UC3875 IC generates the gate drive signal to the MOSFET's. The control loop regulators are implemented using the TL074 IC. A theoretical analysis was conducted, and experimental results were obtained for a 0-50 V/0-10 A power supply operating at 100 kHz     

用PWM芯片实现全桥移相ZVS隔离DC／DC变换器的研究

简述了市场上现有移相控制器的简单情况,分析了全桥移相的工作原理,进而介绍了采用常规PWM控制芯片及全桥驱动器HIP4081A实现50w／500kHz全桥移相ZVS隔离DC／DC变换器,通过有效的利用变压器漏感、MOSFET的输出电感以及MOSFET的体二极管实现ZVS,大幅度降低了开关损耗、热损耗、EMI和RFI。通过深入细致的实验观察,验证了理论设计的正确性、合理性,并给出了相关的实验波形和实验结果分析。     

一种新的移相全桥零电压开关PWM变换器

对于移相全桥零电压开关PWM变换器,在全负载范围内实现所有开关器件零电压开关和减少占空比丢失之间是矛盾的。如果在电路中增加一个辅助电路,根据负载情况在续流期间为滞后桥臂的零电压开关提供能量,能在全负载范围内实现所有开关器件的零电压开关和减少占空比丢失,但电路中存在严重的环流问题。文中提出新的拓扑结构通过增加一个双向开关和相应的驱动电路,有效地减少了环流带来的损耗。实例分析和仿真验证了这种拓扑的优点。     

A Variable Frequency Phase-Shift Modulated Three-Level Resonant Single-Stage Power Factor Correction Converter

This paper presents a new single-stage three-level resonant power factor correction ac-dc converter suitable for high power applications (in the order of multiple kilowatts) with a universal input voltage range (90–265 Vrms). The proposed topology integrates the boost input power factor preregulator with a half-bridge three-level resonant dc-dc converter. The converter operation is controlled by means of a combination of phase-shift and variable frequency control. The phase-shift between the switch gate pulses is used to provide the required input current shaping and to regulate the dc-bus voltage to a set reference value for all loading conditions, whereas, variable frequency control is used to tightly regulate the output voltage. An auxiliary circuit is used in order to balance the voltage across the two dc-bus capacitors. Zero voltage switching (ZVS) is also achieved for a wide range of loading and input voltage by having a lagging resonant current in addition to the flowing of the boost inductor current through the body diodes of the upper pair of switches in the free wheeling mode. The resulting circuit, therefore, has high conversion efficiency and lower component stresses making it suitable for high power, wide input voltage range applications. The effectiveness of the proposed converter is verified by analysis, simulation, and experimental results.      

大功率高频软开关电化学电源的设计

本文介绍了一台大功率高频软开关电化学电源(1 5V/2000A)的设计方案,该电源的主电路采用串联型ZVS移相全桥电路拓扑。文中给出了谐振参数设计的详细过程,并且在实验中对谐振参数进行了进一步优化,有效拓宽了滞后桥臂软开关的实现范围,大大降低了开关损耗,提高了电源工作效率。样机运行结果证明了所提出设计方案的可行性。     

Analysis of Two Continuous Control Regions of Conventional Phase Shift and Transition Phase Shift for Induction Heating Inverter under ZVS and NON-ZVS Operation

This paper proposes an analysis of two continuous control regions of conventional phase shift and transition phase shift for a full-bridge series resonant inverter operating under zero voltage switching (ZVS) and nonzero voltage switching (NON-ZVS) conditions with the load of induction heating. A number of circuit operations for the cases of conventional phase-shift and transition phase-shift control regions under ZVS and NON-ZVS conditions are analyzed first. Various voltage and current equations of the operating circuits are then obtained and used for calculation of the waveforms with the aid of the MATLAB program. The calculated waveforms make possible the consideration of some important circuit parameters that are used to determine ZVS or NON-ZVS conditions. The theoretical results and the proposed method are also verified by experiments, using a prototype test set in our laboratory.      

非对称半桥式开关电源的分析与设计

非对称半桥电路拓扑采用脉冲宽度调制技术,具有易实现零电压开关的优点,可广泛应用于家用电器,汽车电子等领域中。文中首先介绍了非对称半桥电路的工作原理,接着对其进行了稳态分析,重点给出了一个非对称半桥式开关电源的设计过程。考虑到拓扑结构参数和零电压开关的影响,对电路的输出电压进行了修正。此外,谐振电感和死区时间是确保零电压开关实现的两个重要参数,文中给出了其实际的设计过程,并通过仿真证明了其实现的可行性。     

Bidirectional phase-shifted DC-DC converter

A novel ZVS phase-shifted DC-DC converter is proposed. The converter operates at a constant switching frequency and the voltage conversion ratio is regulated by phase-shift control. It has bidirectional power flow capability and synchronous rectification, hence the on-state voltage drop of the devices is small. This is an ideal candidate for electric vehicles (EVs)