Methods and systems for a variable displacement bent axis piston motor are described. In one example, a variable displacement bent axis piston motor comprises a bent axis unit (BAU) rotary group including a cylinder block coupled to a drive shaft of the bent axis piston motor, and an electric actuator coupled to a servo piston of the bent axis piston motor, wherein a displacement of the BAU rotary group is controlled by an inclination angle between the drive shaft and a valve plate of the BAU rotary group coupled to the cylinder block, the inclination angle controlled by the servo piston, the servo piston controlled by the electric actuator. The servo piston is controlled by the electric actuator based a feedback control system, which may switch between various control strategies for adjusting the inclination angle based on different driving scenarios.

The present disclosure relates to a method, a device, and a system for controlling a hydraulic pump of a construction machine, the system comprising: an engine; an engine control unit configured to control the engine by using engine limit torque information and current engine torque information of the engine; a hydraulic pump operated by power supplied from the engine; at least one actuator driven by a hydraulic pressure discharged from the hydraulic pump; and a hydraulic pump control device configured to control a limited swash plate angle of the hydraulic pump by using a torque of the hydraulic pump and the engine limit torque information received from the engine control unit.

The invention relates to a method and to an apparatus for vibration compensation in a piston compressor, the piston compressor of which is driven by means of a crankshaft by a three-phase motor controlled by a frequency converter, wherein the current position the crankshaft of the piston compressor is determined, and based on this the frequency converter, a torque (M.sub.M) for the three-phase motor is predetermined, which torque follows the load torque (M.sub.L) of the piston compressor in order to reduce the vibration stimulation of the entire piston compressor.

A monitor and control system for a hydraulic fracturing pump is described herein to reduce or eliminate harmful oscillations in fluid discharge pressure caused by the pump load dynamics. The monitor and control system receives various sensor data from the operation of the pump, including the pump crank position, and executes a pump control equation or model based on the pump sensor data, pump load data and/or pump speed data. Pump control equations or models are specific to the design and dynamic operation of the pump, incorporating the number of plungers, pump dynamics, motor lag and motor dynamics, etc. Using the pump control equations or models, the monitor and control system determines control commands for the pump motor to reduce or eliminate the oscillatory discharge pressure at the pump.

There are several methods to propel moving force points on a pumping unit. One of the embodiments is propulsion utilizing permanent magnets. This invention can aid the several methods and provides the push start that allows initiating permanent magnet propulsion. This invention relates to an end return device for assisting positioning drives to actuate the continuous movement by mechanical means of moving force points to a desired advantageous position at a desired advantageous moment to achieve reduced net torque when lifting or lowering an unbalanced load with a beam with a fulcrum and connected to a load and an effort. In one embodiment, a walking beam well pumping unit, the lifting and lowering of the well load can be caused by the reciprocating motion of a beam tipping on a fulcrum and with moving effort force point, moving crank shaft force point, and moving beam weight force point.

A method and system for determining the pump fillage of a sucker rod pumping system using torque feedback when pumping wellbore fluids from the particular well on which the sucker rod pumping system is installed. During the pump stroke, a microprocessor samples torque of the pump's mechanical system at an associated horsehead position at regular intervals and once the stroke is completed the raw torque samples and associated horsehead positions are placed in an array, the array of raw torque samples and horsehead positions can be filtered by the microprocessor into a second filtered array and then converted by the microprocessor into a rotatum array (derivative of torque with respect to time) of one or both of the raw or filtered arrays and stored as a rotatum array. The down stroke portion of the rotatum array is then analyzed by the microprocessor to determine the horsehead position when the piston of the down hole pump encounters wellbore fluid in the well (pump fillage). The microprocessor, based on the determined pump fillage, adjusts the speed of the pumping system to maintain an optimal pump fillage determined to be the most economical for the particular well on which the sucker rod pumping system is installed.

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.

Systems and methods are disclosed herein that include providing a service life monitoring system that includes a rotatable component and a rotatable measurement interface disposed on the rotatable component, the rotatable measurement interface having at least one torsional strain gauge configured to measure a strain of the rotatable component, a strain monitor controller configured to receive the measured strain of the rotatable component, and a wireless data transmission component configured to wirelessly communicate with the strain monitor controller to receive the measured strain, determine at least one of a power, rotational speed, torque, and service life of the rotatable component in response to receiving the measured strain of the rotatable component as a result of the measured strain of the rotatable component, and control at least one of the power, the rotational speed, and the torque of the rotatable component.

A controller of a suction valve control system may receive an initiation indication indicating an initiation of a prime mover for a fluid pump. The fluid pump may have a plurality of suction valves, and a plurality of valve control components may be configured to control actuation of the plurality of suction valves. The controller may cause, responsive to the initiation of the prime mover, the plurality of valve control components to maintain the plurality of suction valves in open positions during one or more discharge cycles of the fluid pump.

Variable displacement pump including: i) a pumping piston for pumping the fluid; ii) a sliding seat along which a stroke of the piston takes place; a sliding of the piston along the seat corresponding to a rotation of the seat; iii) a system for regulating the torque absorbed by the pump, in turn including a means for regulating a displacement of the pump as a function of an electrical signal. The regulating means in turn including: - a structure with variable inclination for regulating the stroke length of the pumping piston and thus the displacement of the pump; - a fluid-dynamic actuator for regulating the inclination of the structure; - a control means for controlling the actuator as a function of an electrical signal.