一种基于开关电容的基准电压源

提出了一种基于开关电容的基准电压源,其输出基准电压低于1.25 V。通过增加输出级电路,保证了连续时间内输出稳定的基准电压。采用开关电容电路消除了运放输入失调电压的不利影响。采用SMIC 0.13 μm EEPROM工艺进行了流片,电路面积为0.007 mm²。测试结果表明,该基准电压源在常温下输出的基准电压为820 mV,在1.1~1.7 V电源电压范围内的电压调整率为2.336 mV/V,在-40 ℃~80 ℃范围内的温度系数为6.75×10-5/℃。     

具有快速瞬态响应的电压模式Buck变换器

针对电压模式的Buck变换器,提出了一种新颖的参考电压可选择设计方案。在负载电流改变的情况下,通过参考电压选择电路和阈值电压控制电路来选择不同的参考电压,加快占空比的改变。采用SMIC 0.18 μm CMOS工艺进行设计与仿真,结果表明,该变换器在负载发生590 mA瞬态变化时的输出过冲电压小于50 mV,并且瞬态恢复时间小于12 μs。与传统的电压控制模式相比,该变换器具有更好的瞬态响应性能。     

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。     

Buck–Boost-Type Unity Power Factor Rectifier With Extended Voltage Conversion Ratio

A buck-boost-type unity power factor rectifier is proposed in this paper. The main advantage of the proposed rectifier over the conventional buck-boost type is that it can perform input power factor correction (PFC) over a wider voltage conversion range. With a single switch, a fast well-regulated output voltage is achieved with a zero-current switch at turn-on. Moreover, the switch voltage stress is independent of converter load variation. The proposed converter is well suited for universal offline PFC applications for a low power range (<150 W ). The feasibility of the converter is confirmed with results obtained from a computer simulation and from an experimental prototype.     

A Frequency Delta-Sigma Analog-to-Digital Converter Operating at a Power-Supply Voltage of 0.6 V

This paper describes a delta-sigma analog-to-digital converter operating at a power supply voltage of 0.6V. The converter is implemented in a standard AMS 0.6 m double poly process, and consists of afrequency-delta-sigma modulator where the transistor threshold voltage is decreased by floating-gatetechniques.     

基于DSP控制的电压型PWM整流器

根据PWM整流电路的工作原理,分析了PWM整流控制方式,采用滞环电流控制方式,以TMS320F2812为控制器组建了电压型PWM整流器双闭环自动控制系统。实验结果表明,该系统具有良好的静态、动态性能。为设计PWM整流器提供了一定的理论依据。     

开关电容boost—buck功率因数校正组合开关变换器

文章提出了一种基于开关电容网络的boost-buck组合开关变换器,当其输入环节工作在不连续导电模式（DCM）时,具有功率因数校正（PFC）功能,详细分析了这类变换器的工作原理、临界条件、输入输出电压变比以及各器件的应力。实验结果与理论分析相符。     

A Zero-Voltage and Zero-Current Switching Three-Level DC–DC Converter With Reduced Rectifier Voltage Stress and Soft-Switching-Oriented Optimized Design

A novel zero-voltage zero-current switching (ZVZCS) three-level converter with pulsewidth modulation (PWM) phase-shift control is proposed. The ZCS of the lagging switch is obtained by using a regenerative passive snubber in the secondary. In order to reduce the voltage stress on the rectifier's diodes, a few passive elements are inserted into the primary: a small inductance, two diodes, and a small additional winding of the main transformer. In each half-cycle, one of these diodes will conduct for a short time in order to clamp the voltage of the snubber's capacitor, and thus, the rectifier stress, at$(n_2/n_1)(V_ in/2)$,$n_1$, and$n_2$being the transformer's primary and, respectively, secondary turns number. The three-level configuration allows for the reduction of the voltage stress across the power switches to half of the input voltage$V_ in$. The conditions for assuring ZVS of the leading switch and ZCS of the lagging switch are found. Design constraints on the parallel capacitances of the switches of the leading switch, on the snubber's holding capacitor, and on the additional inductance and winding are hence established, allowing for an optimized design of the converter parameters. A dc analysis allows for the calculation of the effective duty cycle, which enjoys a boost effect due to the proposed snubber. Thus, a further reduction of the primary current stress and rectifier voltage stress is obtained. All the improvements conclude in a high efficiency. The influence of the choice of the parameters' values on the regulation capability is pointed out. Experiments on a prototype of 4.5kW confirm the results.     

基于开关电容DC-DC转换器的两路主从输出策略

传统的多路输出开关电容直流-直流转换器的线性调整率与负载调整率不够理想。针对这一问题,文中采用两路时分复用的输出方法,在控制开关相位交织的情况下,分别对主路和从路进行能量传输,并给出具体的调制策略。该输出策略中,主路采用脉冲频率调制,从路则采用脉冲跳跃调制。同时,文中引入平均频率概念,实现了对驱动能力的量化表征。在Cadence软件下进行电路设计,并进行仿真。仿真结果表明,主路的线性调整率为3.01%,负载调整率为3.54%;从路的线性调整率为3.75%,负载调整率为4.28%。     

基于DCM模式的高压输出反激变换器

设计了一种工作在不连续导电模式(DCM)下的高压输出反激变换器.详细分析了工作在连续导电模式(CCM)和DCM的反激变换器稳态输出/输入传递函数,比较了这两种模式在不同负载条件下的电压输出能力.在理论分析的基础上得出:在一定的负载条件下,工作在DCM状态的反激变换器比工作在CCM状态下的反激变换器更适合高压输出电路.在试验电路上对这一结论进行了验证.     

基于电压空间矢量的三相PWM整流器控制研究

首先建立了三相电压型PWM整流器的数学模型，并对其矢量控制策略进行了分析，在此基础上提出了一种简单的电压空间矢量算法，该算法根据参考电压矢量在坐标系上的分量直接计算电压空间矢量在各个扇区内的作用时间，实验结果验证了所提出控制算法的可行性。     

一种基于损失电压分析的开关电容功率转换器静态模型

介绍了一种适用于多相交错开关电容功率转换器的静态模型。分析了电容与电容之间的电荷传递行为,将开关电容功率转换器中的电荷再分配损耗和开关导通损耗等价地描述为电荷传递子过程的电压损失。该模型可以简便、准确地描述任意开关频率下开关电容功率转换器的等效输出电阻。同时,运用了一种新的“比例电流近似”方法,建立了带电流负载时的电荷传递模型,用以描述和分析负载和输出去耦电容对电容功率转换器静态特性的影响。相比于传统模型,提出的模型在中等开关频率下能准确地描述开关电容功率转换器的静态特性,同时能准确地描述多相交错控制中开关电容功率转换器的输出电压纹波。     

一种峰值电流模两相交错Buck转换器

提出了一种降压型两相交错直流转换器。与传统单相转换器相比,该两相转换器具有输出纹波低、瞬态响应快、重载效率高等特性,适合为多核处理器供电。采用峰值电流模式,基于公共电压反馈回路及峰值电流信息,实现两相支路电流的均衡。依据负载电流范围自动选择运行支路个数,保证转换器在整个负载范围内具有高转换效率。基于TSMC 0.18 μm工艺进行设计,电源电压范围为2.7~5 V,支持330 nH~1 μH的小封装电感,最大电流驱动能力为5 A。仿真结果显示,在输入电压为4.2 V,输出电压0.9 V的条件下,整个负载范围内转换器的峰值效率为86%,最大稳态输出纹波低于2 mV,在5 A/1 μs负载瞬变条件下,负载调整率不超过28 mV/A。     

A High-Voltage DC–DC Converter With Vin/3—Voltage Stress on the Primary Switches

A high-voltage dc-dc converter with low voltage stress on the power switches and high output current capacity is presented. This converter exhibits three distinct features. First, the voltage stress on the primary switches is only one-third of the input voltage, so that switches of low voltage rating and thus of low on-resistance can be used. This leads to reduced conduction loss. Second, all the switches are soft-switched, so that the switching loss can be reduced. Third, the rectifier is a current tripler, so that the output current capacity, and thus the power handling capacity of the converter are increased. A 5.1-kW, 1000-V/48-V dc-dc converter prototype has been built and tested. Experimental results are favorably compared with theoretical predictions.     

基于MOSFET ZTC工作点的高阶曲率补偿电压基准

工作在饱和区的MOSFET存在零温度系数(ZTC)特定工作点,基于这一特性设计实现了一款具有低温度系数的电压基准芯片。所设计的电路利用ZTC工作点的温度系数接近于0这一特点,辅以高阶曲率补偿电路,实现极低温度系数的输出电压。此外,针对ZTC工作点对工艺偏差的敏感性,根据蒙特卡洛仿真结果,专门设计了熔丝修调电路,以保证电路的输出结果具有较高工艺稳定性。该电路在CSMC 0.18μm CMOS工艺平台进行了流片验证,芯片面积为0.0025 mm²。结果表明该芯片在室温时能够稳定输出475.5 mV电压,在-40~125℃内,温度系数达到1.8×10^-6/℃,在10 kHz时电源抑制比达到-68.7 dB。     

三相PWM整流器滞环空间矢量控制的研究

本文介绍了三相PWM整流器的一种基于不定频滞环的空间矢量脉宽调制（sVPWM）电流控制方法。该方法结合了滞环电流控制和SVPWM电流控制的优点,在取得快速电流响应的同时又能有效地降低开关频率,提高系统的运行效率。用Simulink模块库建立仿真模型,仿真结果表明了该控制策略的可行性。     

基于空间电压矢量的三相电压型PWM整流器的研究

建立了三相电压型PWM整流器在三相静止坐标系和两相同步旋转坐标系下的数学模型,将双闭环工程设计方法应用于PWM整流器,研究了其前馈解耦控制策略。在此基础上结合空间矢量调制（SVPWM）的算法,设计了三相电压型PWM整流器控制系统,并在Matlab的Simulink中进行了系统仿真。仿真结果表明,设计方法可行,具有良好的动静态性能,实现了单位功率因数。     

An Interleaved AC–DC Converter Based on Current Tracking

In this paper, an interleaved AC-DC converter based on current tracking without any current sharing required is presented and applied to a two-phase flyback converter. This is realized using two critical-conduction-mode (CRM) pulsewidth-modulated chips, together with a field-programmable gate array technique. By doing so, not only are the total harmonic distortion and the power factor improved but the output power is also upgraded. In this paper, the circuit operation is described in detail, with some experimental results given to verify the proposed control scheme.     

A Three-Phase Current-Fed Push–Pull DC–DC Converter

In this paper, a new three-phase current-fed push–pull dc–dc converter is proposed. This converter uses a high-frequency three-phase transformer that provides galvanic isolation between the power source and the load. The three active switches are connected to the same reference, which simplifies the gate drive circuitry. Reduction of the input current ripple and the output voltage ripple is achieved by means of an inductor and a capacitor, whose volumes are smaller than in equivalent single-phase topologies. The three-phase dc–dc conversion also helps in loss distribution, allowing the use of lower cost switches. These characteristics make this converter suitable for applications where low-voltage power sources are used and the associated currents are high, such as in fuel cells, photovoltaic arrays, and batteries. The theoretical analysis, a simplified design example, and the experimental results for a 1-kW prototype will be presented for two operation regions. The prototype was designed for a switching frequency of 40 kHz, an input voltage of 120 V, and an output voltage of 400 V.      

电流不连续状态下LLC谐振型DC/DC变换器的分析与最佳设计

分析了LLC谐振型DC/DC变换器整流二极管电流工作在不连续状态的最大谐振电流、电容最大电压、输入输出电压增益与开关频率、谐振电感比和负载之间的关系特性,根据推导出的表达式,应用MATLAB软件绘制了相应的曲线,由此得出了LLC谐振变换器的参数最佳设计的方法。最后根据此方法设计了实验参数,给出了实验结果。