Well water depth monitor

Abstract

Methods, apparatuses, and computer readable medium including computer program products, are provided for determining the depth of water in a well. A method may include coupling a signal onto a cable connected to a submersible well pump. The method may further include monitoring the cable to determine a first time corresponding to a first reflection of the signal caused by the cable entering a water column between a water surface and the submersible pump. The method may further include monitoring the cable to determine a second time corresponding to a second reflection of the signal caused by an impedance mismatch between the cable surrounded by water and a motor in the submersible well pump. The method may further include determining a water height between the submersible pump and the water surface from the first time and the second time.

What is claimed is: 
     
         1 . A method comprising:
 coupling a signal onto a cable connected to a submersible well pump;   monitoring the cable to determine a first time corresponding to a first reflection of the signal caused by the cable entering a water column between a water surface and the submersible pump;   monitoring the cable to determine a second time corresponding to a second reflection of the signal caused by an impedance mismatch between the cable surrounded by water and a motor in the submersible well pump; and   determining a water height between the submersible pump and the water surface from the first time and the second time.   
     
     
         2 . The method of  claim 1 , wherein the water height is determined from a difference between the first time and the second time, and wherein the water height is a distance in the water column between the submersible pump and the water surface. 
     
     
         3 . The method of  claim 1 , wherein a cable length between a point corresponding to the launching of the signal and the water surface is determined based on the first time. 
     
     
         4 . The method of  claim 1 , wherein a cable length between a point corresponding to the launching of the signal and the motor in the submersible pump is determined based on the second time. 
     
     
         5 . The method of  claim 1 , wherein the signal comprises a voltage step. 
     
     
         6 . The method of  claim 1 , wherein the cable comprises a power cable providing power to the submersible pump. 
     
     
         7 . The method of  claim 1 , wherein the water height is sent wirelessly to at least one of user equipment or a computer. 
     
     
         8 . The method of  claim 1 , wherein the cable is insulated. 
     
     
         9 . The method of  claim 1 , wherein the cable comprises one or more metal conductors. 
     
     
         10 . The method of  claim 1 , wherein the coupling the signal onto the cable, the monitoring the cable to determine the first time, and the monitoring the cable to determine the second time are performed at a well head. 
     
     
         11 . An apparatus comprising:
 a coupler to couple a signal onto a cable connected to a submersible well pump;   a monitor to monitor the cable to determine a first time corresponding to a first reflection of the signal caused by the cable entering a water column between a water surface and the submersible pump, wherein the monitor further determines a second time corresponding to a second reflection of the signal caused by an impedance mismatch between the cable surrounded by water and a motor in the submersible well pump; and   a calculator to determine a water height between the submersible pump and the water surface from the first time and the second time.   
     
     
         12 . The apparatus of  claim 11 , wherein the water height is determined from a difference between the first time and the second time, and wherein the water height is a distance in the water column between the submersible pump and the water surface. 
     
     
         13 . The apparatus of  claim 11 , wherein a cable length between a point corresponding to the launching of the signal and the water surface is determined based on the first time. 
     
     
         14 . The apparatus of  claim 11 , wherein a cable length between a point corresponding to the launching of the signal and the motor in the submersible pump is determined based on the second time. 
     
     
         15 . The apparatus of  claim 11 , wherein the signal comprises a voltage step. 
     
     
         16 . The apparatus of  claim 11 , wherein the cable comprises a power cable providing power to the submersible pump. 
     
     
         17 . The apparatus of  claim 11 , wherein the water height is sent wirelessly to at least one of a user equipment or a computer. 
     
     
         18 . The apparatus of  claim 11 , wherein the cable is insulated. 
     
     
         19 . The apparatus of  claim 11 , wherein the cable comprises one or more metal conductors. 
     
     
         20 . The apparatus of  claim 11 , wherein the coupling the signal onto the cable, the monitoring the cable to determine the first time, and the monitoring the cable to determine the second time are performed at a well head. 
     
     
         21 . A non-transitory computer-readable medium encoded with instructions that, when executed by at least one processor, cause operations comprising:
 coupling a signal onto a cable connected to a submersible well pump;   monitoring the cable to determine a first time corresponding to a first reflection of the signal caused by the cable entering a water column between a water surface and the submersible pump;   monitoring the cable to determine a second time corresponding to a second reflection of the signal caused by an impedance mismatch between the cable surrounded by water and a motor in the submersible well pump; and   determining a water height between the submersible pump and the water surface from the first time and the second time.