电量监测计准确测算手持设备电池剩余电量

随着移动设备中高清视频和数据传输等新功能的增加,消费者希望移动设备能像笔记本电脑一样工作,也能显示剩余电池电量.     

测量手持设备电池使用寿命的电量监测计

系统侧电池电量监测计bq27500采用Impedance Track技术，该技术能准确测量源自设备单体锂离子电池的数据，以便在各种条件下（甚至是电池老化）测算出剩余电池电量。该芯片能通过比较电池电压、电池阻抗或电阻以及电流积分，准确分析充电状态，根据测算的放电曲线上调或下调剩余充电状态。     

创新阻抗跟踪技术可精确计算电池剩余电量

德州仪器(TI)最近在电池管理方面又取得突破性进展，推出功能独特的阻抗跟踪(Impedance Track)“电量监测计”技术，该技术可在电池整个寿命周期内以高达99％的精确度计算锂电池组的剩余电量。     

STC3115：剩余电量指示芯片

ST推出电池剩余电量指示芯片STC3115,器件采用多项可改善长期监控准确度的创新专利技术,适用于大量生产的手持电子产品。     

针对单节电池供电应用的电量监测技术

如何在电池整个生命周期内,或在电池处于过温状态及使用负载的情况下,对电池的剩余电量进行精确测量是很困难的事情。本文将介绍如何利用最新的电量测量技术——阻抗跟踪来解决电池电量精确监测的难题,文中还列举了单节锂离子电池组解决方案的简单设计案例。     

采用单片电压变换器实现手持设备电池功率变换

延长电池工作时间是便携式电子产品中最难实现且非常重要的一项工作。如果再考虑设备的体积、重量及成本因素,设计任务就更加艰巨。其中由体积限制引入的问题最多,这不仅是因为它直接限制了电池容量,而且还影响电源变换器的设计,变换器中的储能或传能元件如电感和电容,其损耗与体积成反比,体积越小。功耗越大。效率越低。几乎所有的便携式产品都有某种类型的高速数字处理电路,它们通常要求有很稳定的电源。从技术上讲,未经稳压的电源也可以供这类设备正常工作,因此它们可通过电池直接供电,然而这种方式在实际产品中却很少被采用,…     

针对医疗设备的精确电池备份

本文通过测试测量方案介绍了如何进行医疗设备的精确电池备份。     

Atmel推出首款可完全配置的单芯片智能电池解决方案

Atmel公司日前宣布推出一款高电压技术AVR微控制器——ATmega406，首次在单一芯片上实现含有2—4个电池单元的锂离子智能电池监测与保护功能。ATmega406微控制器包含一种用于确保设备获得4V至25V电压的片上稳压器。他同时还具有用于充电、放电和预先充电的3个最高耐压25V的FET驱动，以及用于电池平衡的片上FET。     

设计高效能的手持设备照明解决方案

现今的便携设备不单功能越来越多,而且对功率的需求也越来越大,这对便携电池的电源设计构成很大的挑战.然而,如果对有关应用的能源消耗有更深入的认识,便可设计出更加节能的解决方案,这不单可以延长电池的寿命,而且可以提供更好的用户体验.     

蓄电池剩余电量测量与分析系统

设计一种基于内阻法监测蓄电池剩余电量的系统,首先通过单片机驱动内部AD模块来采样蓄电池上的开路电压和短路电流,然后计算得出蓄电池的剩余电量,并将结果显示在液晶显示器上.将电池的各种参数存入单片机内部的EEPROM存储器中,使用单片机内部的FLASH来模拟EEPROM可以最大限度地节省硬件成本.     

具有声光报警功能的数字化油量表

此油量表是利用与油箱中油量相关的电压信号通过一系列数字集成电路处理 ,用于显示汽车中汽油的油量和缺油声光报警 ,达到提醒驾驶员及时加油的目的。     

基于BP神经网络的飞机燃油量测量改进算法

油量测量计算方法是飞机燃油系统设计的关键技术。针对基于虚拟传感器插值方法存在机载体积特性数据库容量庞大的不足,提出基于BP神经网络的改进计算方法。重点讨论了自适应边界值确定与体积特性数据压缩的方法,并以某型飞机油箱为例进行仿真。仿真结果表明,在保证计算精度的前提下,可极大地减少机载计算机的数据量。     

Multilevel Inverter Topologies for Stand-Alone PV Systems

This paper shows that versatile stand-alone photovoltaic (PV) systems still demand on at least one battery inverter with improved characteristics of robustness and efficiency, which can be achieved using multilevel topologies. A compilation of the most common topologies of multilevel converters is presented, and it shows which ones are best suitable to implement inverters for stand-alone applications in the range of a few kilowatts. As an example, a prototype of 3 kVA was implemented, and peak efficiency of 96.0% was achieved.     

独立光伏系统的储能技术研究

储能环节是独立光伏系统的重要组成部分,其优劣直接影响到光伏系统的好坏。文章简要介绍了独立光伏发电系统、储能技术的特殊要求,分析比较了各种储能技术的基本原理、技术特点、发展现状和储能技术在光伏系统中的适用性。     

基于Matlab的独立光伏系统的研究

基于光伏电池的数学模型,在Matlab/Simulink仿真环境下建立具备最大功率跟踪的光伏电池模型;并与Buck-Boost电路结合使用,通过实时计算获得控制脉冲改变输出电压,从而使得独立光伏系统保持最大功率输出。最后通过仿真验证该方案的可行性。     

Signaling for Multimedia Conferencing in Stand-Alone Mobile Ad Hoc Networks

Mobile ad hoc networks (MANETs) are infrastructure-less and can be set up anywhere, anytime. They can host a wide range of applications in rescue operations, military, private, and commercial settings. Multimedia conferencing is the basis of a wealth of "killer” applications that can be deployed in MANETs. Some examples are audio/video conferencing, multiplayer games, and online public debating. Signaling is the nerve center of multimedia conferences—it establishes, modifies, and tears down conferences. This paper focuses on signaling for multimedia conferences in MANETs. We review the state of the art and propose a novel architecture based on application-level clusters. Our validation employed SIP as the implementation technology and OPNET as our simulation tool. Our clusters are constructed dynamically and the nodes that act as cluster heads are elected based on their capabilities. The capabilities are published and discovered using a simple application-level protocol. The architectural principles and the clustering operations are discussed. Our SIP-based implementation is also presented along with the performance evaluation.     

Fundamental-Frequency-Modulated Six-Level Diode-Clamped Multilevel Inverter for Three-Phase Stand-Alone Photovoltaic System

This paper presents a fundamental-frequency-modulated diode-clamped multilevel inverter (DCMLI) scheme for a three-phase stand-alone photovoltaic (PV) system. The system consists of five series-connected PV modules, a six-level DCMLI generating fundamental-modulation staircase three-phase output voltages, and a three-phase induction motor as the load. In order to validate the proposed concept, simulation studies and experimental measurements using a small-scale laboratory prototype are also presented. The results show the feasibility of the fundamental frequency switching application in three-phase stand-alone PV power systems.     

A Stand-Alone, Split-Phase Current-Sourced Inverter With Novel Energy Storage

A topology and switching algorithm are presented for producing split-phase output voltages using a current-sourced inverter (CSI). Split-phase generation has previously been accomplished using voltage-sourced inverters (VSIs). There are some advantages to instead using CSIs, such as improved output voltage waveform quality and built-in overcurrent protection; however, two issues have prevented their adoption to date. First, while a CSI does not require the input boost converter used by a VSI when fed from a low-voltage source, it may require a preconditioning circuit to provide the required dc current. Second, no algorithm for producing split-phase outputs with a CSI presently exists. This paper's two major contributions aim to solve these problems. A simple preconditioning circuit is presented to provide the necessary dc current and store energy in a capacitor bank for use during load transients. A switching algorithm is written to produce balanced split-phase output voltages under a variety of unbalanced loading conditions. It is demonstrated using simulation and experimental results on a 400-W prototype that the proposed system is able to successfully generate balanced output voltages under unbalanced, inductive, nonlinear, and transient loading conditions, while equalizing switch utilization and minimizing output voltage ripple.      

An Improved Utility Interface for Microturbine Generation System With Stand-Alone Operation Capabilities

In this paper, an alternative filter and control approach for the design of a microturbine's utility interface is proposed. The new method employs a unified current-regulated controller to drive the system converter as a power conditioner for the grid-tied operation and an emergent generator for the stand-alone operation, where few current sensors are required to serve the controller for both operating modes. The proposed method had been examined under various scenarios, including the loss of grid and parallel operation. The results help consolidate the feasibility and practicability of the approach for the applications considered     

离网型风力发电机系统的MPPT控制策略研究

风力发电属于可再生能源发电技术,对我国国民经济的可持续发展具有重要意义。文中根据风力机的特性,探讨了追踪、捕获最大风能的方法,研究了一种应用于离网型风力发电机组的MPPT控制策略。