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 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.

To predict and detect a failure in a compressor provided in an air conditioner, the air conditioner is provided with: a heat exchanger; the compressor; piping connecting the heat exchanger and the compressor with each other; and a control unit controlling the compressor and having a compressor failure predicting and detecting means, and in this air conditioner, the compressor failure predicting and detecting means of the control unit includes: a current detecting part detecting a driving current driving the compressor; a pulsation detecting part detecting pulsation in a driving current detected by the current detecting part; and an anomaly determining part predicting or detecting any failure in the compressor based on a magnitude and a duration of pulsation in a driving current detected by the pulsation detecting part.

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 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 system includes a fixed-displacement fluid pump, a motor operatively connected to the fixed-displacement fluid pump, a sensor configured to sense a parameter related to a drive speed of the motor, and a user interface. The pump controller is configured to receive an input from the user interface of a target flow rate of the pump, determine a duty cycle for the motor based on the target flow rate, and control the motor to operate according to the duty cycle. The pump controller is further configured to receive an indication of the sensed parameter related to the drive speed of the motor, determine a measured drive speed of the motor based on the sensed parameter, and iteratively adjust the duty cycle based on a difference between the measured drive speed of the motor and an expected drive speed 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 diaphragm pump (10), in particular for use as a detergent dosage pump, comprises a pump housing (12) with at least a first check valve (14) and a second check valve (16), a fluid chamber (18), a diaphragm (20) defining a wall of the fluid chamber (18) and reciprocatingly movable, driving means (28) with a driving shaft (30) for reciprocating said diaphragm (20), a control unit (36), wherein the driving means (28) is connected to the diaphragm (20) by an eccentric (26) and a con rod (24), wherein the driving means (28) is configured as a gearless drive to directly reciprocate the diaphragm (20). The diaphragm pump (10) according to the invention offers increased cost efficiency and further it is possible to increase the dosing capabilities of the diaphragm pump (10).

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.

To predict and detect a failure in a compressor provided in an air conditioner, the air conditioner is provided with: a heat exchanger; the compressor; piping connecting the heat exchanger and the compressor with each other; and a control unit controlling the compressor and having a compressor failure predicting and detecting means, and in this air conditioner, the compressor failure predicting and detecting means of the control unit includes: a current detecting part detecting a driving current driving the compressor; a pulsation detecting part detecting pulsation in a driving current detected by the current detecting part; and an anomaly determining part predicting or detecting any failure in the compressor based on a magnitude and a duration of pulsation in a driving current detected by the pulsation detecting part.