An electrical submersible well pump assembly has a SAW (surface acoustic wave) sensor on a motor shaft. A SAW electronic circuit mounts to the motor housing. The SAW electronic circuit has an antenna closely spaced to the SAW sensor for monitoring torque on the motor shaft. A controller at an upper end of the well supplies power to the motor. A motor gauge unit mounted to a lower end of the motor transmits signals to the controller. A signal line extends from the SAW electronic circuit to the motor gauge unit for transmitting signals from the SAW electronic circuit to the motor gauge unit, and from the motor gauge unit to the controller.

A hydraulic pressurizing medium supply assembly has an adjustable axial piston machine. An actuating cylinder is controlled by way of a pilot valve. The pilot valve is actuated by a control installation. The control installation, as input variables, has an actual pressure and/or an actual swivel angle of the adjustable axial piston machine. One or a plurality of the input variables are compared with a matching nominal value and a control value is emitted, or in each case a control value is emitted. The controlling of the input variables is part of a first closed-loop control circuit. An underlying second closed-loop control circuit has an input variable which is based on the control variable or the control variables and serves as a nominal variable. A further input variable of the second closed-loop control circuit is an actual delivery-volume adjustment rate of the axial piston machine.

A controller for operating a prime mover of a rod pumping unit includes a processor configured to operate the prime mover over a first stroke and a second stroke. The controller is further configured to compute a first motor torque imbalance value for the first stroke and engage adjustment of a counter-balance. The controller is further configured to estimate a second motor torque imbalance value for the second stroke. The controller is further configured to disengage adjustment of the counter-balance during the second stroke upon the second motor torque imbalance value reaching a first imbalance range.

A displacement pump arrangement, method for operating the displacement pump arrangement and a control device for controlling the displacement pump arrangement provide rotational-speed-variable control of an expeller pump unit for feeding a fluid. The arrangement includes an expeller pump and a drive, the drive being composed of an electric drive motor and a frequency converter, and a control device. The control device controls a state value such as a final pressure of the expeller pump a setpoint value. The control device detects state values of a control variable are supplied by the drive, in particular relating to the position, rotational speed and torque of the drive motor, and adjusts the displacement pump output to reach the setpoint value without using sensors.

A method controls the start-up of an oil pump of a gearbox by a brushless electric motor that has no position sensor. The stator coils are powered from the off mode in a constant-current open-loop control sequence until the pump reaches a speed threshold at which speed regulation switches over to closed-loop control on a setpoint corresponding to the lubrication flow rate required to ensure the reliability of the gearbox, but without in so doing exceeding a current threshold indicative of pump seizure, at which point motor control switches back over to the constant-current open-loop control sequence. The open-loop current setpoint is higher than the threshold for switching over to closed-loop control so that in the open-loop control mode the motor torque available at the pump is higher than in the closed-loop control mode.

In some implementations, a controller may obtain an indication of a first crank angle associated with a first pump, of a dual-pump single-power source system, that is mechanically connected to a power source of the dual-pump single-power source system via a first clutch. The controller may obtain an indication of a second crank angle associated with a second pump, of the dual-pump single-power source system, that is mechanically connected to the power source via a second clutch. The controller may determine that a difference between the first crank angle and the second crank angle is outside of a tolerance of a crank angle difference value. The controller may modulate a fluid pressure associated with at least one of the first clutch or the second clutch to cause the difference between the first crank angle and the second crank angle to be within the tolerance of the crank angle difference value.

Presented herein are systems and methods for attenuating flow ripple generated by a hydraulic pump. In certain aspects, a method and system for operating a hydraulic positive displacement pump according to a stabilized command profile are disclosed, such that flow ripple generated by operation of the pump according to the stabilized command profile is attenuated as compared to operation of the pump according to a corresponding nominal command profile. In other aspects, a pressure-balanced active buffer is disclosed that allow for at least partially cancelling flow ripple in a hydraulic circuit comprising a pump. In another aspect, a method for generating ripple maps for a pump is disclosed. Such ripple maps may be used, for example, to determine the stabilized command profile used to operate the pump, or may be used by the pressure-balanced active buffer to counteract ripple in the hydraulic circuit.

A rig management system is disclosed. The rig management system may be configured to receive information to be used to control shifting of a transmission to prevent cavitation during use of the hydraulic fracturing rig. The rig management system may be configured to determine a flow rate for a pump based on the information. The rig management system may be configured to determine an output torque of the transmission based on the flow rate. The rig management system may be configured to determine a transmission gear for the transmission based on the output torque and a fuel consumption map, wherein the fuel consumption map identifies a respective fuel consumption rate for different combinations of transmission gears and output torques. The rig management system may be configured to cause the transmission to shift into the transmission gear after determining the transmission gear.

A control system may include circuitry configured to: a deterioration level estimation unit configured to estimate deterioration levels of pumping devices based on information about driving forces of the pumping devices; a selection unit configured to select a pumping device from the pumping devices based on a comparison of the estimated deterioration levels estimated by the deterioration level estimation unit; and a pumping control unit configured to control the selected pumping device selected by the selection unit to pump fluid.

A method that includes an electronic application identifying a downlink sequence for execution by a surface control system of a drilling rig, with the sequence including target output values of a mud pump system and/or a drive system. The method includes instructing the control system to operate in accordance with the sequence. The application receives measured output values of the mud pump system and/or the drive system and calculates differences between the target and measured output values. When the differences are within a level of tolerance, then the application identifies the control system as compliant; and when the differences are greater than the level of tolerance, then the application identifies the control system as non-compliant. The method also includes the application receiving data from a BHA of the drilling rig and determining, based on the data received, if a downlink to the BHA was successful.