A compressor driving apparatus, or a home appliance including the same, includes a DC terminal capacitor to store a charge, an inverter to convert direct current associated with the charge of the DC terminal capacitor into an alternating current and output the alternating current to a motor, an output current detection unit to detect an output current flowing in the motor, and an inverter controller to increase a motor speed by starting the motor, and controlling a speed increase of the motor to change based on an increasing slope of a change in an output current detected by the output current detection unit during the speed increase of the motor.

A common mode line-to-ground filter is disclosed which includes but is not limited to a resistor, capacitor and a ground. The common mode line to ground filter is connected on a high side of a step-up transformer. A low side of the step-up transformer is connected to a variable frequency drive that provides a semi-sinusoidal voltage waveform. The common mode line to ground filter generates a filtered sinusoidal waveform from the output of the step-up transformer. The filtered sinusoidal voltage waveform is supplied via an electrical cable to an electrically submersible pump deployed downhole.

A drive apparatus of an electric motor which does not include a position detection sensor, the drive apparatus includes drive portion configured to drive the electric motor on the basis of a command value inputted from outside, a number-of-rotations detection portion configured to detect a number of rotations of the electric motor driven by the drive portion, an out-of-phase judgement portion judging that the electric motor is out of phase in a case where the number of rotations detected by the number-of-rotations detection portion is less than a predetermined threshold value, and the predetermined threshold value being configured to be changed on the basis of the command value inputted from outside.

A driving circuit of fluid pump module includes a microprocessor, a primary boost circuit, and a pump driving circuit is provided. The microprocessor receives an output signal with a large-width variable rectangular waveform, a driving voltage, a first detection current-feedback signal, and a second detection current-feedback signal. The primary boost circuit converts an inputted driving voltage into a direct current with a certain high voltage. The pump driving circuit receives the certain high voltage and is connected with the microprocessor to receive the voltage control signal and the pulse-width modulation (PWM) signal. The secondary boost circuit receives the certain high voltage to boost the certain high voltage into a working voltage for the fluid pump. The operation driving circuit receives the working voltage and provides the pulse-width modulation signal for the fluid pump through the second detection current-feedback signal.

An air compressor system operably coupled to a power supply including an air storage tank and an air pump including an air manifold having an inlet configured to receive ambient air. The air pump is fluidly coupled to the air storage tank. The air compressor system also includes a motor having a first current level provided by the power supply to operate the air pump, a valve member in fluid communication with the inlet of the air manifold, and a controller operable to move the valve member to either increase or decrease a rate of ambient air traveling into the manifold. The controller monitors the first current level of the motor to change the rate of ambient air traveling into the manifold.

Provided is a method for detecting a ripple voltage. A control device is provided with: an acquiring unit which acquires the voltage value of an input voltage of a battery-driven electric compressor at irregular intervals; and a waveform computing unit which computes the waveform of a ripple component of the input voltage on the basis of the acquired voltage value.

A system, method, and computer-readable medium for determining the flow rate and fluid density in an electrical submersible pump (ESP) and controlling the ESP based on the flow rate and density. In one implementation, an ESP system includes an ESP, drive circuitry, a current sensor, a voltage sensor, and a processor. The ESP includes an electric motor. The drive circuitry is electrically coupled to the ESP and is configured to provide an electrical signal to power the ESP. The current sensor is configured to measure a current of the electrical signal. The voltage sensor is configured to measure a voltage of the electrical signal. The processor is configured to calculate speed of a shaft of the electric motor based on a frequency induced by rotation of the motor detected in the current. The processor is also configured to calculate a density of fluid in the ESP based on the speed.

An electric submersible pump (ESP), comprising: an intake that suctions fluids into the ESP, wherein the fluids include a mixture of gas, water, and oil; a discharge that discharges the fluids from the ESP; an acoustic intake transducer that determines the speed of sound in the fluids suctioned into the ESP at the intake; and a first acoustic discharge transducer that determines the speed of sound in the fluids discharged from the ESP, wherein the speed of sound of the fluid at both intake and discharge is used to calculate a gas volume fraction difference of the multiphase fluid mixture across the intake and discharge of the pump, and wherein the gas volume fraction difference is used as feedback to control the ESP.

A method for determining operating properties of a drill-rod borehole pump, having a pump head, which is connected to a kinematics converter via a drill rod, and the kinematics converter is driven by an electric motor, and furthermore a measuring device is provided for measuring the power consumption of the motor during operation of same.

An operating method is used for a compressor of a refrigerating machine, where the compressor includes an electric motor- and a power supply device configured to modulate a supply voltage and/or current and/or frequency for driving an electric motor. The method includes (a) setting a stator resistance calibration value and at least one threshold value for a control parameter, the threshold value being correlated to the calibration value; (b) injecting, continuously during operation of the electric motor, a disturbance signal into the electric motor (c) detecting a resulting voltage signal and a resulting current signal, corresponding to the perturbation signal; (d) associating with the control parameter a value calculated as a function of the resulting voltage signal and a resulting current signal; and (e) regulating or interrupting the supply voltage and/or current and/or frequency depending on the control parameter with respect to the at least one threshold value.