基于温差发电的改进W型反射式超声波热量表设计

Design of improved W-type reflective ultrasonic heat meter based on thermoelectric power generation

随着超声波热量表在市场上应用的增多,对超声波热量表的运行稳定性以及测量精度的要求也越来越高。从节约能源的角度出发,设计选取高精度时间转换芯片TDC-GP22,配合具有超低功耗特点的MSP430系列单片机作为MCU,同时采用超声波换能器和Pt1000温度传感器形成流量温度测量系统,并采用改进W型反射式基表结构提高流量测量精度。为了延长超声波热量表的使用周期,设计基于TEG1-241系列温差芯片的发电装置,并实现剩余电量为锂离子电池充电。考虑到环境中电磁干扰对测温精度影响较大,采用均值滤波的方法减小因干扰带来的误差。最后在A类环境下对多组热量表进行测试,实验结果表明,该热量表准确度高,静态工作电流低,性能稳定,具有广阔的应用前景。

With the application increase of the ultrasonic heat meters in the market,the requirements for higher runningstability and measuring accuracy of the ultrasonic heat meter are presented. Proceeding from the energy saving,the high?preci?sion time conversion chip TDC?GP22 matching with the ultra?low power consumption MSP430 serial microcontroller is selectedas the MCU,the ultrasonic transducer and Pt1000 temperature sensor are adopted to form the flow and temperature measure?ment system,and the improved W?type reflective basic meter structure is used to improve the measuring accuracy of flow. In or?der to prolong the use cycle of the ultrasonic heat meter,a power generating set based on TEG1?241 series temperature differencechip was designed,by which the lithium?ion battery can be charged up with its remaining capacitance. In consideration that theelectromageric interference in surrounding environment can affect on the temperature measurement accuracy greatly,the meanfiltering method is adopted to reduce the error caused by interference. The multigroup ultrasonic heat meters were tested in Aclass environment. The results show that the heat meter has the characteristics of high accuracy,low static working current,good stability,and wide application prospect .