A motor drive control device has a control circuit that generates a drive control signal for controlling a rotational speed of a motor based on a speed command signal indicating a target rotational speed of the motor, and a motor driving unit that drives the motor based on the drive control signal. The control circuit performs speed feedback control for generating the drive control signal so that the rotational speed of the motor coincides with the target rotational speed when the target rotational speed is lower than a rotational speed threshold value, and generates the drive control signal based on a relationship between current flowing through the motor and a reference current value when the target rotational speed is higher than the rotational speed threshold value.

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, method and computer program for predictive maintenance on natural gas compressors through auditory detection. Using one or multiple microphones, a system will collect and evaluate sound waves for the purpose of predicting and detecting failures and alert conditions in mechanical and process equipment. The system will collect sound which is used in a machine learning environment to utilize supervised training as well as unsupervised training, to produce a normal baseline and detect abnormal operations. Additionally, abnormal operations are categorized against known conditions. For uncategorized and unknown conditions, a workflow is in place to allow for the retraining and learning of new conditions which are then published to the entire network of devices.

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 conduction noise filtering circuit configured to inhibit conduction noise is provided. The conduction noise filtering circuit includes a first coil part configured to be supplied with alternating current (AC) power, a second coil part configured to be connected to the first coil part in series, a detector configured to detect common mode noise from at least one selected from the first coil part and the second coil part, and a capacitor configured to supply a current offsetting common mode noise between power lines connecting the first coil part and the second coil part in series.

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 conduction noise filtering circuit configured to inhibit conduction noise is provided. The conduction noise filtering circuit includes a first coil part configured to be supplied with alternating current (AC) power, a second coil part configured to be connected to the first coil part in series, a detector configured to detect common mode noise from at least one selected from the first coil part and the second coil part, and a capacitor configured to supply a current offsetting common mode noise between power lines connecting the first coil part and the second coil part in series, based on an output signal of the

A pump for pumping a cryogenic fluid includes an activation portion that includes at least one actuator. The activation portion contains oil that may be cooled by the cryogenic fluid. The pump further includes a pumping portion that includes at least one pumping element, the at least one pumping element being operated by the at least one actuator, and a heater associated with the activation portion and configured to, when the heater is active, transfer heat energy to the activation portion such that the oil contained in the activation portion is warmed.

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.