基于叉指微电极的新能源车电池冷却液电导率变送器设计

Design of New Energy Vehicle Battery Coolant Conductivity Transmitter Based on Interfingered Microelectrode

针对电动汽车电池冷却液电导率实时监测的需求,提出一种面向新能源车低电导率电池冷却液的电导率变送器。该电导率变送器中电导率传感器采用基于硅基叉指微电极与Pt电阻一体化结构,可同时实现电导率检测与温度传感,极大降低了敏感元件的体积;使用高性能嵌入式处理器芯片作为传感器的控制核心,配合外围检测电路实现温度和电导率数据的采集和处理,应用分段补偿算法实现电池冷却液电导率-20~90℃大温区的温度补偿。经过实际测试,所设计的电导率传感器在0~20μS/cm的量程范围内误差小于±1.5%,满足新能源车电池冷却液的测量精度要求。因此,提出的电导率变送器在电池冷却液电导率测量方面拥有较强的竞争力。

In response to the demand for real-time monitoring of the conductivity of electric vehicle battery coolant,this paper proposed a conductivity transmitter for low conductivity battery coolant in new energy vehicles.The conductivity sensor in this conductivity transmitter adopted an integrated structure based on silicon based interdigital microelectrodes and Pt resistors,which can simultaneously achieve conductivity detection and temperature sensing,greatly reducing the volume of sensitive components.Using high-performance embedded processor chips as the control core of the sensor,combined with peripheral detection circuits to collect and process temperature and conductivity data,and segmented compensation algorithms were applied to achieve temperature compensation for the battery coolant conductivity in the large temperature range of-20℃to 90℃.Through the actual test,the error of the designed conductivity sensor is less than±1.5%in the range of 0~20μS/cm,which meets the measurement accuracy requirements of the new energy vehicle battery coolant.Therefore,the conductivity transmitter proposed in this paper has a strong competitiveness in the measurement of battery coolant conductivity.