【作者】 陆佳颖；

【导师】 吴晓波； 赵梦恋；

【作者基本信息】 浙江大学 ， 电路与系统， 2010， 硕士

【摘要】 当前,能源短缺使得节能和新能源的研究受到越来越多的关注,而便携式电子产品的的发展及其功能的不断提升更对电源技术提出新的挑战,包括更低的电压和功耗水平,以及便于补充能量等,这就使太阳能电池和微型燃料电池等新能源进入人们的视野。为促进它们在便携电子产品的应用,超低电压启动及驱动等问题成为亟待解决的技术关键。基于上述背景,本文提出一种适用于超低压电源便携式电子产品的电源管理系统。该系统以太阳能电池或者微型燃料电池等超低压电压源作为输入,把输入的不稳定的低压转化成合适的稳定电平,给便携式产品的充电器提供电源,对便携式产品的锂电池进行充电。在有电网覆盖的地方,系统又可以作为一个通用的充电器,以USB接口等外部稳压电压源对便携式产品的锂电池进行充电。所提出的系统主要由两部分组成,第一部分是能够把太阳能电池或者燃料电池等提供的较低且不稳定的输入电压,转化成稳定输出的超低压Boost转换器;第二个是为便携式产品的电池充电的锂电池充电管理器。两个子系统既可以组合起来构成一个完整的多功能便携式产品充电管理系统,也可以分别单独应用。论文首先针对低压输入的条件,提出了一个分阶段双端切换供电的低压Boost系统方案。与常规Boost系统相比,本文提出的系统增加了低压启动模块,实现了低输入电压时系统的正常启动。在控制策略上,系统采用了峰值电流的控制方式,并进行了环路补偿,实现了快速响应和高精度控制。然后,论文给出了一个线性锂电池充电控制器的设计。此控制器可以以Boost电路的输出作为输入,构成低压充电管理系统;也可兼容USB等直流电压源作为输入。该控制器具有应用电路简单,具备过温、过流保护功能,充电时间和充电电流可编程等特点。本文设计的低压Boost控制器在TSMC 0.35μm工艺下进行了设计和仿真;锂电池线性充电控制器则在1.5μm BCD工艺下进行了系统仿真和流片,仿真和测试的结果验证了系统的设想,系统能够在超低压的条件下启动并正常工作,系统自身的充电器能够充电过程的精确控制和对电池的保护。更多还原

【Abstract】 Recently,energy shortage makes research on energy-saving and new energy resourse gather more attentions.At the same time,the rapid development of portable electronic products and the trends of their function strengthening challenge the power supply technology including the operation capability under lower voltage with lower power dissipation.In addition,it should be easy to "recharged",which makes the new energe resourses like solar cell and micro fuel cell come into sight,However, since they features very low output voltage,the key problem to implement their applications in portable products is the capability under very low output voltage as well as the drver capability of such a system.Based on the above application,this thesis proposed a power management system for portable electronic products,which is applicable to ultra-low-voltage power supply.Taking an ultra low voltage source like solar cell or micro-fuel cell as input,the system changes its low and unstable input voltage into an appropriate and stable level.Thus it can provide power for portable product’s charger through the common interface to recharge its lithium betteries.Otherwise,,with USB interface or an external voltage source,it can derectly recharge the lithium battery for portable devices where covered by power grid.In this case the system could be used as a general charger..The proposed system is mainly composed of two sub-systems.The first one is an ultra-low-voltage BOOST converter that converts a relatively low and unstable voltage provided by solar cells or fuel cells into a stable supply voltage.The second one is a lithium battery charger for portable digital products.Both they can work independently.If put them into a system and make them work in cooperation,they can form a multi-function charge management system.To meet the low input voltage condition,a multi-period double-ended supplied low voltage BOOST system control scheme was proposed.Different from traditional BOOST systems,a low voltage startup module was added to this system to realize low input voltage startup working.Peak current control was adopted in loop control strategy design.An appropriate loop compensation was applied to the BOOST system to achieve fast response and high control precision.Meanwhile,a linear lithium battery charger controller was designed based on multiple control parameter competition method in this thesis.The battery charger controller can take the output of the low voltage BOOST system as an input to form a low voltage charger management system.It is also compatible with other DC inputs such as USB interfaces.Through monitoring the temperature,charging current and charging voltage at the same time,the multiple control parameter competition method controls the charge process according to real-time state of the system,which optimizes the charge efficiency and realizes the bettery protection.In addition,the proposed charger controller features its easy application,reliable temperature protection for both chip and battery and programmable charging time and current function.The low voltage BOOST system was designed and simulated in 0.35μm TSMC technology.And the linear lithium battery charger was simulated and implemented in 1.5μm BCD technology.The simulation and test results are consistent with theoretical design well.It is verified that the system can work in ultra-low input voltage and the charger can perform precise control and fine battery protection.更多还原