Average Transformation Theory--Based Capacitive Level Sensor With Anti-Attachment

The modern level measurement is very important in the industry. So it is more instructive to study and improve the capacitive sensor, which is widely used in the Held of level measurement.Firstly, the paper give the general description on the progress of sensor ami predicts the development trend of transducer. Moreover, it draw the conclusion that sensors integraflcation and fuzzyflcation is inexorable trend. Secondly, the paper expounds and summarizes all kinds of level sensors and points out that capacitive sensor is a kind of potential level sensor in present level measurement. However, capacitive sensor will produce attachment error when it is used in attachment substance. Because of this, applying of capacitive level is limited. In the third chapter of article, it is based on the theory of average thansformation and the feature of attachment, the formula that resistance of electric attachment is equal to the value of capacitance between sensor's electrode and attachment is work out. From this, the attachment error can be eliminated by measuring the plural number resistance of sensors electrode.At last, the theory of anti-attachment based on average transformation is proved by experiment. In the experiment, a new anti-attachment smart capacitive sensor is designed. The sensor is testified much better than the conventional sensor in measuring the electric attachment.