A downhole pumping system includes a downhole pump that includes a motor and is configured to circulate a downhole fluid from a subterranean reservoir to a terranean surface; a production tubing string positioned in the wellbore from the terranean surface to the subterranean reservoir and fluidly coupled to the downhole pump; a wellbore seal positioned in the wellbore and configured to fluidly isolate a first portion of an annulus that is uphole of the downhole pump from a second portion of the annulus in which the downhole pump is positionable; and a pump power cable electrically connected to the motor and to a power source cable in the first portion of the annulus with a power connector, where each of the pump power cable and the power source cable includes a metal jacket that encapsulates the respective cable.

A pump monitoring system for use in wellbore operations can determine whether an indication of a failure is due to an actual pump issue or a failed sensor. The pump monitoring system includes a sensor on a fluid end of a pump to measure properties associated with the pump and a vibration detector. A computing device executes instructions to receive the sensor signal and the vibration signal and identify an irregularity in the sensor signal. The processor then determines whether an operational signal component is present in the vibration signal, and displays an indication that the sensor has failed when the operational signal component is not present in the vibration signal. If the operational signal component is present in the vibration signal, the irregularity is likely caused by a pump problem such as a failed valve.

A pumping system for fracking fluid is designed to provide nearly constant flow rate. The pumping system includes a set of linear actuator pumping units, each driven by at least one electric motor. Each pumping unit includes a hollow threaded shaft driven by the linear actuator, two hollow cylinders fixed to an interior of the hollow shaft, and hollow pistons in each of the hollow cylinders. The hollow cylinders and hollow pistons form two pumping chambers. A first pumping chamber expels fluid when the linear actuator is moving in a first direction and a second pumping chamber that expels fluid when the linear actuator is moving in an opposite direction. The speeds of the actuators are coordinated such that a total flow rate of the pumping system is substantially constant.

A power supply controller includes a driver having a circuit board and controlling an operation of an electric oil pump, a control unit controlling power supply to the driver, a board temperature sensor detecting a temperature of the circuit board; and an oil temperature sensor detecting a temperature of a working oil of a transmission as an oil temperature. The control unit executes energization prohibition control for prohibiting power supply to the driver when the temperature of the circuit board detected by the board temperature sensor exceeds a predetermined first threshold temperature, and executes cancellation determination for determining whether to cancel the energization prohibition control based on the oil temperature detected by the oil temperature sensor during execution of the energization prohibition control.

A method is provided for controlling a pump driven by a motor with the motor connected to a drive. The method can include determining a parameter value related to a fault condition, comparing the parameter value to a threshold value, and adjusting a speed control of the drive based on the comparison of the determined parameter to the threshold value.

Systems and methods to pump fracturing fluid into a wellhead may include a gas turbine engine including a compressor turbine shaft connected to a compressor, and a power turbine output shaft connected to a power turbine. The compressor turbine shaft and the power turbine output shaft may be rotatable at different rotational speeds. The systems may also include a transmission including a transmission input shaft connected to the power turbine output shaft and a transmission output shaft connected to a hydraulic fracturing pump. The systems may also include a fracturing unit controller configured to control one or more of the rotational speeds of the compressor turbine shaft, the power turbine output shaft, or the transmission output shaft based at least in part on target signals and fluid flow signals indicative of one or more of pressure or flow rate associated with fracturing fluid pumped into the wellhead.

A method for operating an electric air compressor assembly. The assembly includes an electric motor and a compressor which is mechanically coupled to the electric motor and which is capable of providing compressed air to a tank The method comprises monitoring the temperature of at least one component of the electric air compressor assembly and controlling the motor speed as a function of said temperature running the motor at a first speed S1, which results in the temperature increasing; when the temperature reaches a temperature threshold, which is lower than a maximum admissible temperature, running the motor at a second speed S2>S1 until a predetermined desired pressure in the tank is reached.

A method for determining a current wear (w) of a hydrostatic pump, particularly of a radial piston pump, with a variable-speed drive, where the pump is connected to a fluid passage, in which a fluid is pumped by the pump to create a current actual volume flow in the fluid passage. A current actual volume flow (Q.sub.act) is determined, by measuring the volume flow in the fluid passage at a predetermined drive-vector, a computed volume flow (Q.sub.comp) is determined, by a first computational method, at the predetermined drive-vector, and the current wear (w) of the pump is determined, by a second computational method, which relates the current actual volume flow (Q.sub.act) to the computed volume flow (Q.sub.comp).

A system for monitoring flow conditions of fluid flowing from a product container through a solenoid pump. The system includes at least one solenoid pump comprising a solenoid coil, which, when energized, produces a stroke of the solenoid pump, at least one product container connected to the at least one solenoid pump wherein the at least one solenoid pump pumps fluid from the at least one product container during each stroke, at least one PWM controller configured to energize the at least one solenoid pump, at least one current sensor for sensing the current flow through the solenoid coil and producing an output of the sensed current flow, and a control logic subsystem for controlling the flow of fluids through the solenoid pump by commanding the PWM controller and for monitoring the current through the solenoid pump by receiving the output from the current sensor, wherein the control logic subsystem uses the measured current flow through the solenoid coil to determine whether the stroke of the solenoid pump is functional.

A control device for a compressor includes an operation stop control unit that stops the compressor in a procedure different from a normal stop request signal when a signal different from the normal stop request signal that requests the compressor to stop in a predetermined procedure and a forced stop request signal from a device including the compressor is detected. The operation stop control unit stops the compressor in the different procedure according to a speed of the compressor when the forced stop request signal is detected.