【作者】 李霞；

【导师】 冯林；

【作者基本信息】 大连理工大学 ， 通信与信息系统， 2009， 硕士

【摘要】 目前,我国大部分煤矿设备仍延用铅酸蓄电池作为电源,铅酸蓄电池的使用有如下缺陷:容量密度低、体积大、重量大、不便于携带;其内部硫酸外溢会造成设备腐蚀及人员伤害;电池中的铅锑等重金属会对环境造成污染;循环使用寿命短,维护繁琐。但是其价格低,安全性高,所以在矿用设备中一直得以应用。锂离子电池是20世纪90年代发展起来的新型电池,其工作电压高、能量密度高、无记忆效应、自放电小、循环使用寿命长,得到广泛应用。但是,普通的锂离子电池安全性能无法满足矿井应用的要求,故一直没有在煤矿设备上得到应用。近年来发展起来的LiFePO₄电池因其正极材料稳定性高、安全性能优越等特点,正逐步应用于矿用领域。LiFePO₄电池的标称电压（3.2V）和一般的锂离子电池标称电压（3.7V或3.6V）不同,如果用一般的电池充电器充电,会使电池过充而造成损坏,已有的LiFePO₄电池专用充电仪,由于没有采用本质安全型设计,并不能安全的工作于井下环境。针对此问题,本文参照GB 3836.4-2000标准,设计了本质安全型LiFePO₄电池充电仪,实现了井下安全充电,避免了LiFePO₄电池供电设备在井下断电的尴尬。另外,本文还专门设计了本安电源,为LiFePO₄电池充电仪供电,保证其安全地工作。本安电源输入端接至井下110V交流电供电电网,输出端输出LiFePO₄电池充电仪所需的6V直流电压和3A最大电流。本安电源输出端设置了多重限流限压电路,保证了输出的本质安全性。经过实验测试,本文设计的充电仪充电曲线符合LiFePO₄电池的充电特性,充电纹波小,终止充电电压精度高,达到了LiFePO₄电池的充电要求。其本质安全性能符合国家标准GB 3836.4-2000,可安全地工作在煤矿井下。为充电仪供电的本安电源输出电压偏离值小,电压建立时间短,过流过压保护性能良好,符合充电仪的供电要求。本多路充电仪由单片机控制,灵活性较大,可根据需要调节其恒流阶段电流及恒压阶段电压的大小;充电纹波小,为±10mV;终止充电电压精度高,为±0.8%。本充电仪放置在井下,方便井下LiFePO₄电池供电设备的应急充电,具有重要的应用价值。更多还原

【Abstract】 At present,most of the coal mining equipment still use lead-acid batteries as a power supply,the use of lead-acid batteries have the following deficiencies:low capacity density, bulk mass,heavy,not easy to carry;internal equipment corrosion and personal injury caused by sulfuric acid spilled;lead-antimony and other heavy metal in the battery polluting the environment;short use cycle life,rigmarole of maintenance.Despite of these shortcomings, they are used until now,because of its low prices and high security.A new battery--lithium-ion battery is developed in 1990s.With its high load voltage,great energy density,no memory effect,little self-discharge,long cycle life and a series of advantages,lithium-ion battery is widely applied.However,general safety performance of lithium-ion battery applications can not meet the requirements of the mine,so it has not been applied in the coal mine equipment until LiFePO₄ battery is developed in recent years.Because of high stability of the cathode materials and superior performance characteristics,LiFePO₄ battery can be applied to the field of mining.The nominal voltage of the LiFePO₄ battery is 3.2V,different from the voltage of general lithium battery.The nominal voltage of general lithium battery is 3.7V or 3.6V.If charging the LiFePO₄ battery with an ordinary charger,the LiFePO₄ battery will be overcharged or damaged.The existing charger chip specially developed for LiFePO₄ battery did not use intrinsically safe design,and can not be safe working in the mine environment.In order to solve this problem,the paper designed intrinsically safe mine LiFePO₄ battery charging device with reference standard GB 3836.4-2000,which realize the safely charging in the mine to avoid embarrassment of the interruption of power supply of the LiFePO₄ battery powered equipment.In addition,this paper specially designed intrinsically safe power supply for the LiFePO₄ battery-powered instrument to ensure its security work.The supply of intrinsically safe power input is underground power supply network and its voltage is 110V AC.The output voltage is 6V DC which is the LiFePO₄ battery charger need.The maximum output current is 3A.The output terminal of the intrinsically safe power supply set multiple voltage limit and current limit circuit to reach the intrinsically safety requirements.According to the result of experimental tests,the charging curve of the charger in line with characteristics of LiFePO₄ battery charging.The charging ripple is small,precision of the termination charging voltage is high.It reaches charging requirements of LiFePO₄ battery.Its safety performance is in accordance with the national standards GB 3836.4 - 2000 and it can work safely in the mine.With small offset of output voltage,short voltage setup time and good function of over-current and over-voltage protection.The multi-charger is controlled by the MCU,taking on greater flexibility.It can regulate the current in constant current period and voltage in constant voltage period to the value needed;Charging ripple is low to±10mV;precision of the end charging voltage is high,±0.8%.The charger placed in the mine,convenient to the emergency charging of underground equipment which is supplied by LiFePO₄ battery.It has important practical value.更多还原