Systems and methods of controlling the speed of a pump configured to move liquid through a pump system are described. The actual motor speed of the pump motor is controlled by adjusting a current applied to the motor based on the difference between the actual motor speed and the target motor speed according to a gain setting. A first gain value is applied as the gain setting when the difference between the actual motor speed and the target motor speed does not exceed a first threshold. However, a second, higher gain value is applied when the difference between the actual motor speed and the target motor speed exceeds the first threshold.

The present invention relates to the compressors technological field used preferentially in cooling systems. Problem to be solved: Difficulty in detecting improper opening of the high pressure suction valve in multiple suction reciprocating compressor and, in more severe cases, interrupts operation of low pressure line(s). Problem resolution: Implementation of method which monitors at least one variable proportional to electrical engine torque, and based on detection of at least on positive peak of said variable proportional to torque of said electrical engine, identify and/or detectsin real timeimproper opening of the valve.

The invention describes a method for adjusting the pressure in a pumping system (10) of a motor vehicle with an internal combustion engine. The pumping system (10) comprises one or more pumps, wherein each pump is provided with a respective driving motor, and at least one programmable electronic control unit (12). The method comprises the steps of adjusting or mapping the programmable electronic control unit (12) of the pumping system (10), carried out by setting a set of predefined operating parameters of each pump in the programmable electronic control unit (12) of the pumping system (10), and of controlling the operation of the pumping system (10), wherein such control is an open-loop control and wherein the control action is independent from the values of the output parameters of the pumping system (10).

A controller that controls an electric compressor, which is mounted to a vehicle and configures a two-stage compression refrigeration cycle device, has a deceleration section, an operation stop section, and a restart section. The deceleration section reduces a rotational speed of an electric motor by controlling an AC current which is output to the electric motor, when a two-stage compression mode, in which an intermediate-pressure refrigerant flows into the electric compressor from an intermediate-pressure port, is performed and an operation stop request to stop the electric compressor is made. The operation stop section stops the electric motor after the deceleration section reduces the rotational speed of the electric motor. The restart section restarts the electric compressor when the operation stop request is canceled after the operation stop section stops the electric compressor.

A pump has a signal processor, including one forming part of a printed circuit board assembly, that receives signaling containing information about a voltage supplied to a motor to run a particular pump model, and also containing information about whether a current draw of the pump is lower than a predetermined low current level or is higher than a predetermined high current level; and determines whether to shut off the pump after a predetermined time, based on the signaling received. The signal processor provides control signalling to shut off the pump after the predetermined time if the current draw of the pump is lower than the predetermined low current level or is higher than the predetermined high current level, where the predetermined low current level and the predetermined high current level depend on the voltage being supplied to the motor to run the particular pump model.

The present disclosure relates to a method of monitoring an electric motor serving to drive a pump, wherein, within a time interval T, current values are measured, an average value of the current values measured is determined and this average value is compared to a predetermined reference value. According to the disclosure, it is provided that the method extends to controlling the electric motor, wherein the current values measured reflect the profile of the winding current of the electric motor and, irrespective of whether they can be associated with an instantaneous maximum value of the current profile, are included in determining the average value, and wherein the average value is considered by the motor control as input parameter.

A power converter including a compressor as a load includes a compensation current output (80) allowing compensation current (Ic), which compensates for leakage current (Ia), to flow. A controller (50) receives a detection signal from a rotational speed sensor (55) which senses the rotational speed of the compressor (CM). When the rotational speed has increased to a set rotational speed at which the leakage current (Ia) is lower than or equal to its limiting value (Lmax) (e.g., the limiting value specified under the Electrical Appliances and Materials Safety Act or by the IEC) in a state where the compensation current output (80) is off, the compensation current output (80) is switched from an on state to an off state. This may reduce the leakage current from the compressor with low power loss.

A method and system of controlling driving of a brushless DC electric motor (BLDC) of an electric water pump are provided. The method includes estimating an initial position of a rotor using a magnitude of a current detected in a three-phase coil wound on a stator and converting a current magnitude that reflects a rotational angle of the rotor with respect to the initial position into two direct currents based on the three-phase current. The converted direct currents are output and a rotational angle, a speed, a flux and a torque of the rotor are acquired based on values of the three-phase current, a voltage generated according to flow of the three-phase current, a predetermined coil resistance, and an inductance input. A speed of the motor is then adjusted based on the acquired rotational angle, speed, flux, and torque of the rotor.

A method for regulating a fuel delivery system without a pressure sensor. The fuel delivery system has a fuel delivery pump, an electric motor, and an evaluation unit. The fuel delivery pump is driven by the electric motor, which is actuated using control variables such that a prespecifiable fuel delivery is achieved. At least two different submethods are executed for ascertaining control variables, which are ascertained in the respective submethod and are supplied to an evaluation unit. The control variables are evaluated regarding their plausibility in the evaluation unit and the electric motor is actuated based on the ascertained control variables from only one or a plurality of submethods.

A method for determining a pressure value in a fluid conveying system of a motor vehicle, the vehicle having an actuable electric motor and having a fluid feed pump drivable by the electric motor, includes: determining a rotational speed of the electric motor; determining an actuation current of the electric motor; acquiring a pressure value as a function of the determined rotational speed and the determined actuation current of the electric motor; processing the acquired pressure value with at least one external state variable in a controller; and correcting the acquired pressure value.