燃料电池蓄电池混合供电系统

燃料电池是一种清洁、环保的可替代能源,但昂贵的价格限制了其推广。本文结合燃料电池、蓄电池的优点,提出燃料电池与蓄电池混合供电方式,降低系统成本。为了减小输入电流纹波延长电池使用寿命,变换器均采取交错并联拓扑。文中详细分析了系统工作原理及其控制方式,仿真结果验证了系统设计方案的可行性。     

Influence of Battery/Ultracapacitor Energy-Storage Sizing on Battery Lifetime in a Fuel Cell Hybrid Electric Vehicle

Combining high-energy-density batteries and high-power-density ultracapacitors in fuel cell hybrid electric vehicles (FCHEVs) results in a high-performance, highly efficient, low-size, and light system. Often, the battery is rated with respect to its energy requirement to reduce its volume and mass. This does not prevent deep discharges of the battery, which are critical to the lifetime of the battery. In this paper, the ratings of the battery and ultracapacitors are investigated. Comparisons of the system volume, the system mass, and the lifetime of the battery due to the rating of the energy storage devices are presented. It is concluded that not only should the energy storage devices of a FCHEV be sized by their power and energy requirements, but the battery lifetime should also be considered. Two energy-management strategies, which sufficiently divide the load power between the fuel cell stack, the battery, and the ultracapacitors, are proposed. A charging strategy, which charges the energy-storage devices due to the conditions of the FCHEV, is also proposed. The analysis provides recommendations on the design of the battery and the ultracapacitor energy-storage systems for FCHEVs.     

一种宽电压输入数字控制的功率因数校正器

为改善供电系统的供电质量,提高电能的利用率,提出了一种宽电压(交流电压有效值为85~264 V)输入、兼容50 Hz/400 Hz频率的功率因数校正器。该校正器通过对输入交流电压进行采样,实现了供电系统对频率的自适应调节。主电路采用四路交错并联的升压电路,有效降低了电流谐波,改善了供电质量。采用并联均流技术,以适应供电系统的功率扩充需求,同时增强了供电系统的可靠性和灵活性。通过数字控制技术和合理的控制算法,降低了供电系统的复杂度,增强对不同输入条件下的适应性。     

A Microprocessor-Based Synchronization Scheme for Digitally Controlled Three-Phase Thyristor Power Converters

This paper presents a microprocessor-based scheme that generates the necessary synchronization logical signals for three-phase static power converter control systems. The problem of detecting the phase-to-phase voltage zero-crossing in presence of noise generated by thyristor commutations in constant and in variable frequency supplies is discussed, and a microcomputer software solution is proposed.     

电动汽车的未来 第25届世界纯电动车、混合动力车和燃料电池车大会暨展览会

2010年11月5日至9日,第25届世界纯电动车、混合动力车和燃料电池车大会暨展览会在深圳成功举行。这次电动车大会暨展览会的主题是"可持续动力革命"。顾名思义,可持续动力就是指生生不息的动力,同时也是未来汽车工业的发展方向,全球汽车工业的领跑者都把开发新能源放在了最重要的位置。中国目前是全球最大的汽车市场,中国政府已明确提出了大力发展电动汽车(EV)等电动车辆的方针,因此这次EVS25大会是一个前瞻汽车未来潮流、窥探新能源发展的最佳舞台。本次展览会期间,约有350家企业及大学等机构参会,约60家以中国公司为主的企业展出了电动车辆及外围设备。本次展会齐聚了知名汽车企业家、学者、教授、工程技术人员于一堂,展示世界纯电动车、混合动力车和燃料电池车等新能源与节能环保汽车、汽车零部件最新技术发展以及成果,共同探讨其未来发展方向。     

Materials Research Advances towards High-Capacity Battery/Fuel Cell Devices

The world has entered an era featured with fast transportations, instant communications, and prompt technological revolutions, the further advancement of which all relies fundamentally, yet, on the development of cost-effective energy resources allowing for durable and high-rate energy supply. Current battery and fuel cell systems are challenged by a few issues characterized either by insufficient energy capacity or by operation instability and, thus, are not ideal for such highly-demanded applications as electrical vehicles and portable electronic devices. In this mini-review, we present, from materials perspectives, a few selected important breakthroughs in energy resources employed in these applications. Prospectives are then given to look towards future research activities for seeking viable materials solutions for addressing the capacity, durability, and cost shortcomings associated with current battery/fuel cell devices.     

双电池系统电源选择器MAX1773/1773A

MAX1773／MAX1773A是用于双电池系统的电源选择器，它允许外部控制器去管理双电池组、适配器输入、电池充电器和系统负载所需的电源连接。文中介绍了MAX1773／1773A的特点、引脚功能、内部结构和工作原理，给出了MAX1773/MAX1773A的典型工作电路。     

Energy Management Power Converters in Hybrid Electric and Fuel Cell Vehicles

Using a bidirectional dc-dc converter along with low-voltage energy storage for the high-voltage dc bus and traction motor drives has been a prominent option for hybrid electric and fuel cell vehicles. This paper will describe the significance of energy management power converters and their circuit topology options for efficiency, size, and cost considerations. Whether isolated or nonisolated, soft switching techniques have been widely used in high-power bidirectional dc-dc converters. Through some design examples, the component selection and circuit design optimization are discussed, and their efficiency evaluation results are also given. Major difficulties of developing a high-power bidirectional dc-dc converter are found in lack of high-power passive components and lack of multiphase dc-dc controllers. More development work needs to be done in these areas     

一种数字控制可调增益放大器

介绍了一种基于R-2R梯形电阻网络原理的CMOS数字控制可调增益放大器,放大器的增益由数字信号控制线性调节,增益调节的步长可根据不同需要调整变换,进行高精度的线性增益调节。     

A Digitally Controlled Stimulator for Neurophysiological Applications

A stimulator circuit is presented which is capable of generating pulse train waveforms suitable for neurophysiological experiments are available, as well as special test conditions such as dishabituation. Digital and linear integrated circuits are used to provide precise control over the stimulus parameters.     

Small-Signal$z$-Domain Analysis of Digitally Controlled Converters

As the performance of microcontrollers has increased rapidly during the last decade, there is a growing interest to replace the analog controllers in low power switching converters by more complicated and flexible digital control algorithms. Compared to high power converters, the control loop bandwidths for converters in the lower power range are generally much higher. Because of this, the dynamic properties of the uniformly-sampled pulse-width modulators (PWMs) used in low power applications become an important restriction to the maximum achievable bandwidth of the control loop. Though frequency- and Laplace-domain models for uniformly-sampled PWMs are very valuable as they improve the general perception of the dynamic behavior of these modulators, the direct discrete design of the digital compensator requires a$z$-domain model for the combination modulator and converter. For this purpose a new exact small-signal$z$-domain model is derived. In accordance with the zero-order-hold equivalent commonly used for “regular” digital control systems, this$z$-domain model gives rise to the development of a uniformly-sampled PWM equivalent of the converter. This$z$-domain model is characterized by its capability to quantify the different dynamics of the converter for different modulators, its ease of use and its ability to predict the values of the control variables at the true sampling instants of the real system.     

Power Semiconductor Devices for Hybrid, Electric, and Fuel Cell Vehicles

Power semiconductor devices are key components in all power electronic systems, particularly in hybrid, electric, and fuel cell vehicles. This paper reviews the system requirement and latest development of power semiconductor devices including IGBTs, freewheeling diodes, and advanced power module technology in relating to electric vehicle applications. State-of-the-art silicon device technologies, their future trends, and theoretical limits are discussed. Emerging wide bandgap semiconductor devices such as SiC devices and their potential applications in electric vehicles are also reviewed     

一个应用于PHS系统的低噪声低功耗全数控LC振荡器

针对PHS通信系统,综合采用了反型数控MOS变容管、数控MOS变容管单元矩阵、动态元素匹配、流水线MASHΣ△调制器等多项旨在提高新型全数控LC振荡器(DCO)性能的电路技术,在SMIC 0.18μm CMOS工艺下设计了一种低噪声低功耗的DCO.经测试得到,该DCO的中心振荡频率为3.1GHz,频率调节范围为120MHz,电源电压为1.8V,电流为2.8mA.当振荡在3.1GHz时,该DCO输出信号在100kHz与1.2MHz频偏处的相位噪声分别为-102.3和-122.6dBc/Hz.测试结果表明,该DCO与国际上DCO设计的最新水平相比,在相位噪声与功耗等方面具有较高的优势.     

一个应用于PHS系统的低噪声低功耗全数控LC振荡器

针对PHS通信系统,综合采用了反型数控MOS变容管、数控MOS变容管单元矩阵、动态元素匹配、流水线MASHΣ△调制器等多项旨在提高新型全数控LC振荡器(DCO)性能的电路技术,在SMIC 0.18μm CMOS工艺下设计了一种低噪声低功耗的DCO.经测试得到,该DCO的中心振荡频率为3.1GHz,频率调节范围为120MHz,电源电压为1.8V,电流为2.8mA.当振荡在3.1GHz时,该DCO输出信号在100kHz与1.2MHz频偏处的相位噪声分别为-102.3和-122.6dBc/Hz.测试结果表明,该DCO与国际上DCO设计的最新水平相比,在相位噪声与功耗等方面具有较高的优势.     

A Digitally Controlled Shunt Capacitor CMOS Delay Line

Delay-controlled CMOS delay lines have been proved useful in a number of applications, notably the digitization of short time intervals. This paper introduces a new kind of CMOS delay line, in which the delay element is an array of capacitors controlled by a digital signal vector. This choice allows for a robust implementation of the circuitry controlling the delay generation, while the maximum speed attainable by the line is high compared to the maximum speed achieved by other delay line architectures. The delay line presented here was designed to produce an accurately tunable 16 × 0.5ns delay under large temperature, supply voltage, and technological process quality variations.     

A UWB-IR Transmitter With Digitally Controlled Pulse Generator

A novel transmitter for ultra-wideband (UWB) impulse radio has been developed. The proposed architecture enables low-power operation, simple design, and accurate pulse-shape generation. The phase and amplitude of the pulse are controlled separately and digitally to generate a desired pulse shape. This digital control method also contributes to the low-power transmission and eliminates the need for a filter. The transmitter is fabricated using a 0.18-mum CMOS process. The core chip size is only 0.40 mm². From experimental measurements, it was found that the generated signal satisfied the FCC spectrum mask, and the average power dissipation was only 29.7 mW at A 2.2-V supply voltage. Therefore, the developed UWB transmitter generates accurate pulses with low power consumption and simple design architecture     

高精度宽带数字控制可变增益放大器的设计

设计了一种高精度宽带数字控制可变增益放大器,利用增益加强技术改进可变增益放大器的步进精度;同时,引入零点抵消技术,并加入源极负反馈电容,在不增加额外功耗的条件下,拓展了带宽。该电路采用0.18μm CMOS工艺,1.8V供电电源,增益动态范围为62dB,步进精度为1dB,步进误差为0.2dB。设计的可变增益放大器可以提供高达80MHz的带宽,整个电路消耗1.5mA电流,芯片尺寸为300μm×800μm。     

Hybrid Solid Oxide Fuel Cell and Thermoelectric Generator for Maximum Power Output in Micro-CHP Systems

One of the most obvious early market applications for thermoelectric generators (TEG) is decentralized micro combined heat and power (CHP) installations of 0.5 kWe to 5 kWe based on fuel cell technology. Through the use of TEG technology for waste heat recovery it is possible to increase the electricity production in micro-CHP systems by more than 15%, corresponding to system electrical efficiency increases of some 4 to 5 percentage points. This will make fuel cell-based micro-CHP systems very competitive and profitable and will also open opportunities in a number of other potential business and market segments which are not yet quantified. This paper quantifies a micro-CHP system based on a solid oxide fuel cell (SOFC) and a high-performance TE generator. Based on a 3 kW fuel input, the hybrid SOFC implementation boosts electrical output from 945 W to 1085 W, with 1794 W available for heating purposes.     

Three-Port Bidirectional Converter for Hybrid Fuel Cell Systems

The implementation of a hybrid fuel cell/battery system is proposed to improve the slow transient response of a fuel cell stack. This system can be used for an autonomous device with quick load variations. A suitable three-port, galvanic isolated, bidirectional power converter is proposed to control the power flow. An energy management method for the proposed three-port circuit is analyzed and implemented. Measurements from a 500-W laboratory prototype are presented to demonstrate the validity of the approach     

氢燃料备用电源应用于通信领域的分析

从介绍氢燃料备用电源的工作原理和特点出发,从技术理论和节能减排的角度讨论了用氢燃料电源作为通信系统备用电源所带来技术上的改进和经济上的效益,提出氢燃料备用电源应用于通信基站的设想,并对通信行业引入氢燃料备用电源后的节能减排技术的研究建议了新方向.