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.

Method and apparatus for improving the performance, response, and durability of an electro-hydraulic active suspension system. The noise caused by hydraulic flow ripple is reduced and system response is improved.

A hydraulic motor apparatus includes a motor housing engaged to an end cap having a first porting system and an adapter connected to an external surface of the end cap and having a second porting system. A filter may be attached to the adapter and connected to the second porting system and a pressure reducing valve in the adapter is connected to the second porting system. The assembly may also include a controller operatively connected to the pressure reducing valve and system sensors measuring parameters affected by the output of the hydraulic motor apparatus, whereby the pressure reducing valve is operatively controlled by the controller in response to input from the system sensors.

Method and apparatus for improving the performance, response, and durability of an electro-hydraulic active suspension system. The noise caused by hydraulic flow ripple is reduced and system response is improved.

Provided are hydraulic systems comprising variable speed drives coupled to hydraulic pumps and methods of operating such systems. The drive speed is controlled based on the position of a hydraulic servo-control valve in order to reduce the flow through a bypass line. Specifically, the drive speed may be decreased as the valve is opening and sending a greater portion of the hydraulic fluid into the bypass line. This approach allows to reducing losses in the bypass line thereby increasing the overall efficiency of the hydraulic system. The position of the hydraulic servo-control valve may be determined using a position sensor or a flow sensor. Alternatively, the position may be estimated by increasing the drive speed and monitoring the pressure change in the hydraulic actuator. The differential pressure-speed ratio obtained during this speed increase is compared to a calibration set of values corresponding to different valve positions.

A hydrostatic system includes a hydraulic system and at least one sensor configured to monitor a parameter of the hydraulic system, the at least one sensor including a wireless transmitter configured to generate wireless transmissions based on the parameter. The hydrostatic system further includes an electronic control box including a wireless receiver that is configured to receive the wireless transmissions generated by the at least one sensor. The electronic control box is configured to control the hydraulic system based at least in part on the received wireless transmissions.

An ultra high pressure pump having a servo motor coupled to a piston having a head arranged within a cylinder to define a pumping chamber, whereby the servo motor rotation causes reciprocal displacement of the piston to pressurize fluid in the pumping chamber to pressures greater than 50,000 psi, the servo motor having a feedback loop coupled to a computer, the feedback loop including a pressure feedback signal to control the pump pressure in real time.

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.

A hydraulic motor apparatus includes a motor housing engaged to an end cap having a first porting system and an adapter connected to an external surface of the end cap and having a second porting system. A filter may be attached to the adapter and connected to the second porting system and a pressure reducing valve in the adapter is connected to the second porting system. The assembly may also include a controller operatively connected to the pressure reducing valve and system sensors measuring parameters affected by the output of the hydraulic motor apparatus, whereby the pressure reducing valve is operatively controlled by the controller in response to input from the system sensors.

A hydrostatic system includes a hydraulic system and at least one sensor configured to monitor a parameter of the hydraulic system, the at least one sensor including a wireless transmitter configured to generate wireless transmissions based on the parameter. The hydrostatic system further includes an electronic control box including a wireless receiver that is configured to receive the wireless transmissions generated by the at least one sensor. The electronic control box is configured to control the hydraulic system based at least in part on the received wireless transmissions.