一种基于窄带物联网的智能水表设计

Design of intelligent water meter based on narrow-band IoT

为了实现将智能水表连入家庭物联网,克服传统水表易腐蚀、无法及时上传水表工作信息给用户的问题,设计基于NB_IoT的智能水表。该智能水表主要由电源管理电路、阀门开关自动控制电路、数据采集电路、电池电量检测电路、NB_IoT模块驱动电路五部分组成。智能水表采用超低功耗单片机STM2L073作为核心处理器,正常情况下水表每30 min会上传一次水用量和电池电量信息给用户端,当出现余额不足或电池电路电量不足情况时,会自动关闭阀门并上传警告帧给用户,提示用户充值或更换电池,当用户交费后水表会自动打开阀门。智能水表不与客户端通信时,单片机软件将NB_IoT模块设置为休眠模式,从而很大程度降低了系统的功耗,延长了电池使用时间。

In order to connect the intelligent water meter into the family internet of things(IoT),and overcome the prob lem that the traditional water meter is easy to corrode and can not upload the work information of the water meter to users in time,an intelligent water meter based on NB_IoT is designed in this paper. The intelligent water meter mainly consists of five parts:power management circuit,valve switch automatic control circuit,data acquisition circuit,battery power detection circuit and NB_IoT module driving circuit. The ultra low power consumption single chip STM2L073 is used in intelligent water meter as its core processor. The intelligent water meter uploads the water usage and battery power information to the client every 30 min utes. When the users′ funds is insufficient or the battery power is low,the intelligent water meter automatically closes the valve and uploads warning information to the clients. If the users′ funds is recharged,the water meter automatically opens the valve. When the intelligent water meter does not communicate with the client,the MCU software sets the NB_IoT module to sleep mode,so as to greatly reduce the power consumption of the system and prolong the battery life.