A method of operating a system (16) for pumping a fluid, which system comprises: a pump (17) for pumping the fluid; and a variable speed motor (20) for driving the pump (17). The method comprises the steps of: identifying a first system parameter (PI); identifying a second system parameter (P2) which is a function of the torque of the pump; setting a target value (P1.sub.0) for a first system parameter; monitoring the first system parameter (PI); establishing a target value (P2o) for the second system parameter based on the difference between the target value and the measured value of the first system parameter; monitoring the second system parameter; and regulating the rotational speed of the pump such that the difference between the monitored value and the target value of the second system parameter is minimised. A system for implementing the method is also disclosed.

A home flood prevention appliance system includes controller circuitry disposed in a shroud above a cover of a sump basin, and a plurality of electrically operated sump pumps disposed in a lower portion of a structural frame positionable below the cover in the sump basin. The system also includes a water control actuator operable as a water main control device for a domestic water distribution network and a flow meter to measure the flow of municipal water supplied to the network. The controller circuitry configured to selectively energize the pumps to extract liquid from a sump basin based on a liquid level in the sump basin. The water control actuator controlled by the controller circuitry to shut off a municipal water supply to the domestic water distribution network in response to detection of a leak. Communication circuitry included in the home flood prevention appliance may wirelessly communicate.

A home flood prevention appliance system includes controller circuitry disposed in a shroud above a cover of a sump basin, and a plurality of electrically operated sump pumps disposed in a lower portion of a structural frame positionable below the cover in the sump basin. The system also includes a water control actuator operable as a water main control device for a domestic water distribution network and a flow meter to measure the flow of municipal water supplied to the network. The controller circuitry configured to selectively energize the pumps to extract liquid from a sump basin based on a liquid level in the sump basin. The water control actuator controlled by the controller circuitry to shut off a municipal water supply to the domestic water distribution network in response to detection of a leak. Communication circuitry included in the home flood prevention appliance may wirelessly communicate.

The invention provides a subsea pump system, comprising a subsea centrifugal pump with a motor compartment and a process compartment, wherein the motor compartment is separate from the process compartment and comprises an electric motor or stator driving a motor shaft, wherein the process compartment comprises a pump arranged on a pump rotor, an inlet for fluid and an outlet for pressure boosted fluid, and wherein the motor shaft via a coupling preferably drives the pump rotor. The subsea pump system is distinguished in that it further comprises a liquid phase separator arranged downstream to the pump or downstream to at least one pump impeller, the liquid phase separator comprising: an inlet receiving the pressure boosted fluid, an outlet delivering a majority, or a minor part, of the pressure boosted fluid, and a liquid phase outlet, a liquid recirculation line, a flow mixer arranged on the inlet side of the pump, wherein the liquid recirculation line is arranged from the liquid phase outlet to the flow mixer, and a liquid lubricant line arranged from a location containing pressure boosted fluid to one or more process compartment bearings, directly or via other equipment, for lubricating said process compartment bearings.

The invention provides a subsea pump system, comprising a subsea centrifugal pump with a motor compartment and a process compartment, wherein the motor compartment is separate from the process compartment and comprises an electric motor or stator driving a motor shaft, wherein the process compartment comprises a pump arranged on a pump rotor, an inlet for fluid and an outlet for pressure boosted fluid, and wherein the motor shaft via a coupling preferably drives the pump rotor. The subsea pump system is distinguished in that it further comprises a liquid phase separator arranged downstream to the pump or downstream to at least one pump impeller, the liquid phase separator comprising: an inlet receiving the pressure boosted fluid, an outlet delivering a majority, or a minor part, of the pressure boosted fluid, and a liquid phase outlet, a liquid recirculation line, a flow mixer arranged on the inlet side of the pump, wherein the liquid recirculation line is arranged from the liquid phase outlet to the flow mixer, and a liquid lubricant line arranged from a location containing pressure boosted fluid to one or more process compartment bearings, directly or via other equipment, for lubricating said process compartment bearings.

A fluid pump assembly is provided. The pump has a pair of units magnetically coupled to each other. The first unit contains a drive motor and a magnetic assembly. The second unit contains a magnetic assembly and a blade of a propeller/impeller for imparting movement to a fluid. As the first unit is activated by the drive motor, a magnetic flux is created which in turn rotates the magnetic assembly in the second unit, driving the blade.

The gas seal column pump may comprise a pump drive, a gas seal column, a seal gas control box, and a pump. A drive motor of the pump drive, the gas seal column, and the pump may comprise a hermetically sealed, vertically-oriented, pumping system where the gas seal column is operable to replace mechanical seals around a drive shaft that couples the drive motor to the pump. A pressurized seal gas pumped into the drive motor and the gas seal column may displace corrosive fumes and the product being pumped. A product level may be sensed using a plurality of level sensors. Responsive to inputs from the level sensors, a seal gas control box may regulate the pressure of the seal gas using a plurality of valves. A bearing shaft adapter may be added to provide a special drive shaft of other lengths, diameters, or materials.

A motor drive and method to control a motor in a fluid system. The method may comprise determining a pressure; determining a proportional error as a limited difference between the pressure and a pressure setpoint; determining an integral step as a limited proportional error; determining an integral error as a limited sum of the integral step and a preceding unbound integral error; determining an error as the product of the integral error, the proportional error, and a gain factor; and generating a control signal to cause the inverter to output a motor voltage to drive the motor and maintain the pressure about the pressure setpoint.

A glanded pump to pump a pumped medium includes a motor to drive a pump shaft of the glanded pump about a longitudinal axis, a controller connected to the motor to control the motor, a pump housing to contain the pumped medium and in which an impeller is provided, and a sealing flange that seals off the pump housing from the motor. The controller is connected to the sealing flange on a side remote from the impeller, and the controller includes a printed circuit board and a ring capacitor thereon, the ring capacitor extending in the longitudinal direction between the printed circuit board and the sealing flange and being in direct contact with the sealing flange in order to provide a thermally conductive contact.

The present invention relates to a filtration unit for filtering the water in a pool or basin, in particular a swimming pool, said unit being mounted behind a wall of said pool, and communicating with said pool via a suction intake (3, 6) and via a delivery orifice to generate a forced flow of water from and back into the pool through a filtration tank and through a suction column by means of centrifugal hydraulic pump. The centrifugal hydraulic pump has an electric motor coupled to a centrifugal turbine housed in a pump body. The electric motor is a sealed, brushless, autonomously controlled motor that is powered at very low voltage and that may advantageously be immersed inside the filtration unit below the level of the water contained in said pool, thereby enabling said motor to be cooled and sound-proofed naturally by the forced flow of the water from the pool, thereby forming a filtration unit and a pool that have low energy consumption.