A ventricular assist device is disclosed. The ventricular assist device may include a centrifugal pump and a controller. The controller may be configured to cause the centrifugal pump to operate at a first speed above a predetermined flow rate. The controller may also be configured to cause the centrifugal pump to operate at a second speed below the predetermined flow rate, wherein the predetermined flowrate is indicative of a crossover point between systole and diastole phases of a person's cardiac cycle.

A terminal box for a centrifugal pump is releasably connectable to an electronic extension module by a locking element. A pluggable electric interface extends through an opening from an underside of the base plate into the terminal box to electrically connect the pump control for establishing a data link. The locking element is slidable in the cavity and is movable manually from a first position to a second position and by a tool from this second position to this first position. It also has on a first side a resilient latch engaging with either a first recess of the terminal box and holding the locking element in the first position, or a second recess of the terminal box holding the locking element in the second position. Thus the locking element frees the module for plugging-in in the first position, and arrests the module in the second position.

An electric submersible pumping system is constructed with an outer housing which contains an integrated pump and motor. The pump may comprise an impeller disposed within a stator of the motor to form an integrated pump and the motor. An electric submersible pumping system includes a stator having a passage extending longitudinally through the stator. A plurality of stages, including impellers and diffusers, are disposed within the passage.

Systems and methods for adjusting the power provided by an electric drive system to an ESP motor through an electrical network based on a model of the system and real-time inputs indicating operating conditions of the system. Some embodiments use a field oriented control system to adjust a direct-axis current setting to generate output power signals which drives the motor at a desired operating point for optimized performance. The electrical network may include a filter, a transformer, and a transmission line. A drive controller may receive real-time operating conditions and motor parameters as input, and may select further system parameters based on the received parameters. The controller builds a model of the electrical network and generates adjustments to the power generated by the drive using the system model and received real-time input. The adjustments may be recalculated at scheduled intervals.

A system for automatically controlling air flow rate within an agricultural system is provided. One system for distributing an agricultural product includes a metering system configured to meter the agricultural product from a storage tank into a conduit. The system includes an air conveyance system to provide an air stream for moving metered agricultural product in the conduit toward a distribution device. The air conveyance system comprises one or more sensors to monitor the product status and/or the air stream inside the conduit. The system also includes control circuitry configured to control air flow rate based on the product status and/or the air stream inside the conduit and/or the geographic location of the system.

Apparatus comprising and methods are described including a blood pump that includes an axial shaft, and an impeller disposed on the axial shaft. The impeller is configured to pump blood of the subject by rotating. The impeller and the axial shaft are configured to undergo axial back-and-forth motion during operation of the impeller. A distal tip element is disposed at a distal end of the blood pump. The distal tip element defines an axial-shaft-receiving tube, configured to receive at least a portion of the axial shaft during forward motion of the axial shaft. The distal tip element additionally defines an atraumatic distal tip portion disposed distally of the axial-shaft-receiving tube. Other applications are also described.

A hydraulic system includes a circulation pump assembly (2) provided with a speed controller (4, 26), a hydraulic circuit (A, B) connected to the circulation pump assembly (2) as well as a mechanical switch device (86, 88; 120, 122; 120″, 122″) which is subjected to pressure from a fluid in the hydraulic circuit (A, B) and which can be moved into at least two different switch positions. The mechanical switch device (28; 86, 28; 120, 122) can be moved by the circulation pump assembly (2) by way of a hydraulic coupling via the fluid. The speed controller is configured to initiate a movement of the switch device (86, 88; 120, 122; 120″, 122″) by way of at least one hydraulic force acting thereon and causing a movement of the switch device (86, 88; 120,122; 120″, 122″), produced via the hydraulic circuit, via a speed adaptation of the circulation pump assembly.

A torque required to achieve the modulated reference speed or adjustment of a modulated torque and the actual speed of the centrifugal pump is determined. Then a model speed is calculated with the aid of a mathematical pump-motor model simulating the behavior of the centrifugal pump within a hydraulic system as well as a disturbance signal from a deviation of the model speed from the actual speed of the centrifugal pump. Then a correction signal is determined by integrating the product of the disturbance signal and a sine or cosine signal with a multiple of the excitation frequency over at least one period of the excitation signal. Finally, at least one model parameter of the pump-motor model is determined as a function of the correction signal and the flow rate and/or the head is calculated using the adapted pump-motor model.

A variable speed pumping system, for an aircraft, comprising: a first electrical machine, the first electrical machine comprising an electrical machine rotor shaft mechanically connected to an engine of the aircraft and electrical machine stator coils; an electric pump motor-generator, the electric pump motor-generator comprising an electric pump rotor shaft mechanically connected to the electrical machine rotor shaft via a one way drive arrangement and electric pump stator coils; wherein the electric pump rotor shaft is mechanically connected to a fluid pumping system.

Apparatus for providing variable speed pump control in a hydronic pump system having a system flow and pressure requirement, featuring a signal processor or processing module configured to: receive signaling containing information about a system characteristic curve, a system flow and pressure requirement for the hydronic pump system, and real time changes by a pump operator to at least one control parameter to adjust the performance of the hydronic pump system; and determine corresponding signaling containing information about a design/redesign of at least one pump, system or control curve to adjust the performance of the hydronic pump system to correspond with the system flow and pressure requirement of the hydronic system, based upon the signaling received.