高精度原油储罐液位计研究

Research on Liquid Level Detector with High Sensitivity and Precision for Oil Tank Level

通过对数字式电容液位计及等值基准电容补偿法的研究 ,提出将数字式电容液位计与压差法相结合 ,由数字式电容液位计测量原油液位和油水界面的高度 ,等值基准电容法补偿由于环境温度、极板腐蚀和油液粘结带来的测量误差 ,采用压差法测量混油密度 ,依据混油密度和液位高度求得油重及容积 ;通过高精度A/D板采集模拟和数字信号 ,连续对储罐内原油的液位、密度、温度等各种参数进行运算 ,并由智能监测仪实施全自动显示 ,其测量精度可达到毫米级。

According to the study of the digital capacitance sensor and equal-value datum-capacitance method,we put forward combining the digital capacitance sensor with differential pressure method.The oil level and oil-water level are tested by the digital capacitance sensor.We apply datum-capacitance method to compensate for the error of capacitance numerical value that causing by the environmental temperature,plate corrosive & oil adhesion.We apply differential pressure method to measure the mix-oil density.According to the mix-oil density and liquid level to calculate the oil weight and the oil volume.The analogue signal & digital signal are collected by the high precision A/D chip.The kinds of parameter such as oil level,thickness,temperature,etc are continuously calculated and automatically display by means of the intelligence monitor.The measuring precision of the oil tank will change to millimetre level.