A flow rate component, such as a bypass valve with a motorized actuator, a variable speed circulation pump, or both, is controlled in realtime by an automatic controlled to regulate water flow rate through a swimming pool heater, such as a heat pump, to optimize heat transfer, minimize energy consumption, and improve life spans of components of the swimming pool circulation, filtering and heating system.

A flow rate component, such as a bypass valve with a motorized actuator, a variable speed circulation pump, or both, is controlled in realtime by an automatic controlled to regulate water flow rate through a swimming pool heater, such as a heat pump, to optimize heat transfer, minimize energy consumption, and improve life spans of components of the swimming pool circulation, filtering and heating system.

Provided are a control method, a control system and an electric valve. The control method includes steps described below. An actually measured setting parameter curve is acquired. A required setting parameter curve is acquired. Both the actually measured setting parameter curve and the required setting parameter curve represent a corresponding relationship between a position of the electric valve and a setting parameter. The actually measured setting parameter curve and the required setting parameter curve are fitted to acquire a position mapping curve. A setting required position is obtained according to a required setting parameter and the required setting parameter curve, and a setting actual position is acquired according to the setting required position and the position mapping curve. The electric valve is controlled to run toward the setting actual position of the electric valve.

A hydraulic system may include an electrohydraulic control valve disposed in fluid communication between a source of pressured fluid and a hydraulic actuator. The hydraulic system may be controlled to correct for offset errors between a target actuator pressure and a current actuator pressure output from the control valve, without amplifying pressure oscillations in the fluid between the control valve and the hydraulic actuator.

A method for controlling a pump-down operation in a wellbore includes selecting a target value for downhole tension of a support cable and a recommended job speed to convey a wireline tool string down a section of the wellbore, generating a line speed signal for controlling a line speed of the support cable and a pumprate signal to control a pumprate of a hydraulic fluid in the wellbore, determining a first error between the target value for downhole tension and a measured value of the downhole tension, determining a second error between the recommended job speed and an actual line speed, and maintaining the target value for the downhole tension by simultaneously controlling the line speed and the pumprate using a value for the line speed signal and a value for the pumprate signal generated based on the first and second errors.

A method for operating a fluid system including the steps: receiving or determining a set value for a stroke of the working valve, determining an actual value for the stroke of the working valve using a sensor signal of a position sensor, determining a deviation value of a working valve in dependence on sensor signals of a supply pressure sensor and a working pressure sensor and a position sensor and a sensor system, and performing a processing of the set value for the stroke of the working valve, the actual value for the stroke of the working valve and the deviation value to a control signal for driving the working valve.

A hydraulic system may include an electrohydraulic control valve disposed in fluid communication between a source of pressured fluid and a hydraulic actuator. The hydraulic system may be controlled to correct for offset errors between a target actuator pressure and a current actuator pressure output from the control valve, without amplifying pressure oscillations in the fluid between the control valve and the hydraulic actuator.

A drive system (10), in particular for process automation, includes: a trajectory planning unit (3), which is adapted to provide a trajectory signal (xd) on the basis of a setpoint signal (xs), and an actuator unit (2) having an actuator member (1), in particular a valve member, which actuator unit (2) is adapted to control and/or regulate a position of the actuator member (1) on the basis of the trajectory signal (xd). The trajectory planning unit (3) is adapted to provide the trajectory signal (xd) with a first signal section (s1) and a second signal section (s2), the first signal section (s1) having a straight signal form and the second signal section (s2) having a signal form asymptotic to the setpoint signal (xs).

Systems, methods and apparatus are provided for leveling and/or supporting a plant chassis. In some embodiments, a first set of actuators carry out a leveling routine and a controller monitors a pressure in a second set of actuators as the second set of actuators is extended.

Systems, methods and apparatus are provided for leveling and/or supporting a plant chassis. In some embodiments, a first set of actuators carry out a leveling routine and a controller monitors a pressure in a second set of actuators as the second set of actuators is extended.