CPC B66D 1/485 (2013.01) [B66D 1/08 (2013.01); E21B 19/084 (2013.01)] | 20 Claims |
1. A method for controlling a hydraulic winch to move a tool string within a wellbore, the method comprising:
receiving, at a controller, measurements from sensors associated with a variable displacement pump of the hydraulic winch;
estimating, by the controller, based on the received measurements:
an effective drum radius of a drum of the hydraulic winch, wherein the effective drum radius includes a cable at least partially wound around the drum; and
an effective mass of the drum, wherein the effective mass accounts for a portion of the cable that is at least partially wound around the drum;
determining, by the controller, a desired movement profile for the tool string, wherein the desired movement profile includes at least a desired tool depth as a function of time;
generating, by the controller, a control command based on the estimated effective drum radius, the estimated effective mass of the drum, and the desired movement profile; and
providing the control command to the variable displacement pump, wherein the variable displacement pump carries out the control command to cause the drum of the hydraulic winch to raise or lower the tool string according to the desired movement profile.
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