Method for determining operating properties of a drill-rod borehole pump, and pump system for same

Abstract

A method for determining operating properties of a drill-rod borehole pump, having a pump head, which is connected to a kinematics converter via a drill rod, and the kinematics converter is driven by an electric motor, and furthermore a measuring device is provided for measuring the power consumption of the motor during operation of same.

1 . A method for determining operating properties of a drill-rod borehole pump, comprising a pump head, which is connected to a kinematics converter via a drill rod, and the kinematics converter is driven by an electric motor, and furthermore a measuring device is provided for measuring a power consumption of the motor during operation of same, the method comprising:
 a) measuring a current consumption and an operating voltage of the motor over at least one pump cycle, with which four operating phases of the borehole pump can be associated in each case, and determining the power consumption therefrom with power values,   b) determining, for one pump cycle, a period and a maximum of the power consumption that corresponds to the torque maximum of the borehole pump,   c) determining a reference phase angle for the kinematics converter with the aid of the properties of the kinematics converter and the power consumption of the motor, which reference phase angle describes a relationship between the maximum of the power consumption and the maximum of the force acting on the drill rod of the borehole pump,   d) ascertaining a torque curve from the power consumption of the motor with the aid of the properties of the kinematics converter,   e) determining the operating properties of the borehole pump from the torque curve ascertained in step d) using the period determined in step b) and the reference phase angle determined in step c).   
     
     
         2 . The method as claimed in  claim 1 ,
 wherein the period is ascertained with the aid of an approximated polynomial by the power values of the measuring points.   
     
     
         3 . The method as claimed in  claim 1 ,
 wherein the period is ascertained with the aid of a polynomial which takes into account statistical mean values of the power values of the respective measuring points over at least five pump cycles for interpolation points of the polynomial.   
     
     
         4 . The method as claimed in  claim 2 ,
 wherein a reference value is ascertained for the measuring points, at which reference value a maximum is present for a change in the particular power value between two directly successive measuring points, and the period is ascertained with the aid of the reference value.   
     
     
         5 . The method as claimed in  claim 1 ,
 wherein the operating properties of the borehole pump are determined with the aid of a load-displacement graph, which is determined from the torque curve determined in step d) using the period determined in step b) and the reference phase angle ascertained in step c).   
     
     
         6 . The method as claimed in  claim 1 ,
 wherein the reference phase angle is determined with respect to the absolute maximum of the power values of the measuring points within a pump cycle.   
     
     
         7 . A pump system with a drill-rod borehole pump, comprising:
 a pump head, which is connected to a kinematics converter via a drill rod, and the kinematics converter is driven by an electric motor, and   a measuring device, which is adapted to measure a power consumption of the motor during operation of same, and   a computing device with a memory which is designed to carry out the method as claimed in  claim 1  with the aid of the measuring device.   
     
     
         8 . A computer-implemented method for determining operating properties of a drill-rod borehole pump, comprising:
 implementing the method as claimed in  claim 1  on a computer.   
     
     
         9 . The method as claimed in  claim 3 ,
 wherein the period is ascertained with the aid of a polynomial which takes into account statistical mean values of the power values of the respective measuring points over at least ten pump cycles for interpolation points of the polynomial.   
     
     
         10 . The method as claimed in  claim 3 ,
 wherein the period is ascertained with the aid of a polynomial which takes into account statistical mean values of the power values of the respective measuring points over at least fifty pump cycles for interpolation points of the polynomial.