Method and System for Fluid Surface Detection

摘要

The present invention pertains to a method for detecting a fluid surface, comprising the following steps: providing at least one probe having an electric capacitance with respect to its surroundings; moving the probe into or out of a fluid; charging the probe by applying a periodic first electric signal to the probe for activating the probe; applying a periodic third electric signal to one or more electrically conductive regions different from the probe simultaneously with applying the first electric signal to the probe, wherein the third electric signal corresponds to the first electric signal or an amplified/damped first electric signal; at least partially discharging the probe so as to obtain a discharging current; detecting a second electric signal based on the discharging current; analyzing the second electric signal or a signal derived from the second electric signal with respect to the capacitance of the probe; identifying the fluid surface of the fluid based on a change of the capacitance of the probe. It further relates to a corresponding system adapted to perform the method.

主权项

1. A method for detecting a fluid surface (10), comprising the following steps:
providing at least one probe (2) having an electric capacitance (C) with respect to its surroundings;moving the probe (2) into or out of a fluid (4);
charging the probe (2) by applying a periodic first electric signal (51) to the probe (2) for activating the probe (2); applying a periodic third electric signal (S3) to one or more electrically conductive regions separate from the probe (2) simultaneously with applying the first electric signal (51) to the probe (2), wherein the third electric signal (S3) is based on the first electric signal (51); at least partially discharging the probe (2) so as to obtain a discharging current;detecting a second electric signal (S2) based on the discharging current;
analyzing the second electric signal (S2) or a signal derived from the second electric signal (S2) with respect to the capacitance (C) of the probe (2); and identifying the fluid surface (10) of the fluid (4) based on a change of the capacitance (C) of the probe (2).