An external gear pump includes a pump housing in which a pump chamber is formed, a primary gear having a plurality of external teeth housed in the pump chamber, a secondary gear having a plurality of external teeth that mesh with the plurality of external teeth of the primary gear in the pump chamber, a first electric motor configured to generate a torque for rotationally driving the primary gear, a second electric motor configured to generate a torque for rotationally driving the secondary gear, and a control unit configured to control the first and second electric motors. The control unit controls the first and second electric motors so that the torque generated by the first electric motor is greater than the torque generated by the second electric motor.

A central distribution unit (CDU) for circulating coolant is disclosed. The CDU may operate under negative pressure and can have a number of operation modes including: normal operation, pump priming, fill, drain, purge and vacuum test. The CDU includes various valves, pumps and sensors, the placement and actuation of which transitions the CDU into the various modes.

In an aspect a system is provided for generating vacuum in a vehicle. The system includes a vacuum pump, an engagement clutch, an actuator, and a torque limiting clutch. The e engagement clutch operatively connects a camshaft to the rotor. The actuator controls the clutch. The actuator is movable, based on air pressure in a vacuum conduit, between a low-pressure position in which the actuator causes the clutch to operatively disconnect the camshaft from the rotor, and a high-pressure position in which the actuator causes the clutch to operatively connect the camshaft to the rotor. The torque limiting clutch limits torque transfer to the rotor when the engagement clutch operatively connects the camshaft to the rotor. The system also provides control hysteresis.

A method of operating a compressor includes obtaining a mechanical angle and an angular speed of a rotor, determining an amplitude of a fundamental harmonic of a periodic load torque exerted on the rotor based at least in part on the mechanical angle and a harmonic series representation of the periodic load torque, obtaining a speed error by subtracting the angular speed from a reference angular speed, determining a DC component of the periodic load torque based at least in part on a speed error and a closed loop feedback control algorithm, calculating an electromagnetic torque using the DC component of the periodic load torque and the amplitude of the fundamental harmonic of the periodic load torque, and operating the electric motor to generate the calculated electromagnetic torque on the rotor.

A heat pump apparatus, including: a two-cylinder compressor including: an electric motor; two compression units to be driven by the electric motor, the two-cylinder compressor being structured to switch between two operation modes including single operation in which one of the compression units is brought into a non-compression state, and parallel operation in which both the compression units are brought into a compression state; an inverter drive control device supplying drive power to the electric motor of the two-cylinder compressor; an operation mode detecting-determining unit determining a current operation mode based on an electric signal acquired from the inverter drive control device; and a capacity control device determining a rotating frequency of the electric motor so that a temperature of a target object is brought close to a set value, to thereby control the inverter drive control device based on a result of determination of the operation mode detecting-determining unit.

A rotary-vane internal combustion engine of the cat and mouse or scissor type with coordinated rotation of two co-axial shafts with position sensors creating chambers of variable volume for intake, compression, power and exhaust strokes. A reversible electric generator motor on at least one of the shafts with an electronic control system for current, an energy storage unit and electrical load. The total work done and angular speed is calculated or empirically determined while an alternating accelerating or decelerating torque is applied for a continuous, uniform rotation cycle.

A pump having a fluid driver disposed within the interior volume of the pump and to a method of delivering fluid from an inlet of the pump to an outlet of the pump using the fluid driver. The fluid driver includes a variable-speed and/or a variable torque prime mover and a fluid displacement assembly. The pump can be used in a fluid pumping system to provide fluid to an actuator that is operated by the fluid. At least one of a speed and a torque of the pump is controlled so as to adjust at least one of a flow and a pressure in the fluid pumping system to a desired set point, without the aid of another flow control device.

The present disclosure describes a load/unload control method for a compressor system with a rotating compressor connected to a pressure vessel. In the method, the present operating state can be monitored on the basis of a monitored/estimated electrical quantity of the compressor system. The method comprises an identification phase and an operational phase. In the identification phase, the compressor is operated at a constant rotational speed to generate two known pressures to the pressure vessel. At least one electrical quantity is monitored, and values of the electrical quantity corresponding to the pressure limits are stored. In the operational phase, reaching of a pressure limit may then be detected by comparing the present value of the monitored electrical quantity to the stored values.

A method of operating a rolling piston rotary compressor includes obtaining an angular position and an angular speed of a rolling piston of the compressor, for example, using a tachometer or shaft encoder or observer. The method further includes obtaining an electromagnetic torque applied by an electric motor that is mechanically coupled to the rolling piston. The method further includes calculating a load torque exerted on the rolling piston based on these obtained values by using a load torque observer model that is formulated using known geometries of the compressor and thermodynamic models for the gas compression process. The operation of the electric motor is then adjusted such that the electromagnetic torque applied by the motor is equivalent to the calculated load torque such that noise and vibrations are minimized.

A central distribution unit (CDU) for circulating coolant is disclosed. The CDU may operate under negative pressure and can have a number of operation modes including: normal operation, pump priming, fill, drain, purge and vacuum test. The CDU includes various valves, pumps and sensors, the placement and actuation of which transitions the CDU into the various modes.