CPC E21B 43/128 (2013.01) [E21B 47/06 (2013.01); E21B 47/12 (2013.01); F04D 13/10 (2013.01); F04D 15/0066 (2013.01); F04D 25/0686 (2013.01); F04D 29/042 (2013.01); F04D 29/048 (2013.01); F04D 29/052 (2013.01); F04D 29/058 (2013.01); E21B 41/0085 (2013.01)] | 17 Claims |
1. A method of controlling a downhole-type rotating machine, the method comprising:
lowering a downhole-type rotating machine into a wellbore of a production well;
sealing, with a seal assembly, the downhole-type rotating machine to a wall of the wellbore;
flowing a fluid through the downhole-type rotating machine from downhole of the downhole-type rotating machine, across the seal assembly, to uphole of the downhole-type rotating machine;
radially supporting a central shaft within an outer housing of the of the downhole-type rotating machine, the central shaft comprising a first permanent magnet and the outer housing comprising a second permanent magnet;
measuring a parameter of a magnetic bearing supporting a rotor in operation within a stator of the downhole-type rotating machine, the downhole-type rotating machine comprising a pump or compressor, and the measured parameter comprising an axial load on the rotor;
determining, based on the measured axial load on the rotor, a change in a pressure ratio of the fluid flowing across the pump or compressor through the downhole-type rotating machine;
automatically adjusting a force on the rotor from the magnetic bearing based on the measured parameter and without external intervention;
controlling a speed of the rotor based on the measured parameter;
determining a future predicted pressure decline rate of the production well in which the downhole-type rotating machine resides, the future predicted pressure decline rate based on a predictive model;
changing a speed of the rotor based on the future predicted pressure decline rate; and
changing an axial position of the rotor, by the magnetic bearing, from a first position to a second position, based on the measured parameter.
|