Devices, systems, and methods for measurement of parameters of electric power transmission lines can improve electric power usage, while wireless circuitry can provide communication from field-located devices. Connection to draw electrical power from the transmission line can be distinct from connection to sense line parameters.

Devices, systems, and methods for measurement of parameters of electric power transmission lines can improve electric power usage, while wireless circuitry can provide communication from field-located devices. Connection to draw electrical power from the transmission line can be distinct from connection to sense line parameters.

A non-intrusive electrical current detector system and method is disclosed. In one example, the system includes a magnetic field sensing device and a controller. The system provides a user with a way to monitor the running status of an electrical device, without the need to make electrical connections or separating conductors in a multi-conductor cable.

A method and apparatus for electrical line testing. The method and apparatus provides audio, visual and/or electronic information to indicate electricity is flowing or not flowing through an electrical circuit controlled by a remote circuit breaker. The method and system help identify which electrical sockets are controlled by which remote circuit breakers. The method and apparatus is used over short distances in a residential home or over long distances in a commercial building such as a warehouse or factory. The method and apparatus is also used via a cloud communications network and with smart speakers. The method and apparatus is used with or without an external network devices such as a smartphone, electronic tablet, wearable device, etc.

A leakage electric field measurement device includes a first acquirer that measures a distance to an electric wire, a second acquirer that measures a leakage electric field of the electric wire, a third acquirer that acquires a captured image of the electric wire, and a controller that calculates a predicted value of the leakage electric field of the electric wire on the basis of the distance measured by the first acquirer and the leakage electric field measured by the second acquirer, performs determination of whether or not the electric wire is a live wire according to comparison between an assumed electric field of the electric wire and the predicted value, and generates a composite image in which a result of the determination is superimposed on the captured image acquired by the third acquirer.

An apparatus for a first current sensor for a switching converter is presented. The apparatus has an inductor and a first switch. The first switch is arranged to selectively couple the inductor to a first voltage. The first current sensor generates a first output current that is dependent on an inductor current flowing through the inductor The first current sensor compensates for an error arising due to the first switch in the generation of the first output current. The apparatus provides an improved current sensor for a switching converter that overcomes or mitigates the problem of errors in the measurement of a current.

An apparatus for a first current sensor for a switching converter is presented. The apparatus has an inductor and a first switch. The first switch is arranged to selectively couple the inductor to a first voltage. The first current sensor generates a first output current that is dependent on an inductor current flowing through the inductor The first current sensor compensates for an error arising due to the first switch in the generation of the first output current. The apparatus provides an improved current sensor for a switching converter that overcomes or mitigates the problem of errors in the measurement of a current.

An electromagnetic apparatus (EMA) for measuring electromagnetic properties of an electrical conductor such as a power cord is provided. Methods of using the EMA are also provided. The EMA includes a plurality of electromagnetic sensors (EMSs) disposed in an array along a length and a width of the EMA. The EMA further includes circuitry such as a microprocessor, communication circuitry, and power circuitry. The circuitry is in electrical communication with the EMSs.

The occurrence of torque in the motor due to an unintentional flow of the q-axis current in the motor during discharging of the smoothing capacitor is reduced. A motor control device according to the present invention controls a system including an inverter including a smoothing capacitor connected to a power source via a relay, a motor connected to the inverter, and a current sensor configured to detect a current flowing through the motor, the motor control device including: an electric discharge control unit configured to discharge, in the motor via the inverter, an electric charge accumulated in the smoothing capacitor; and a current sensor calibration unit configured to calibrate the current sensor in a state where no current in the motor flows during a time period from when the relay is cut off to when discharge control by the electric discharge control unit is started, wherein the electric discharge control unit performs discharge by controlling the current in the motor based on a value of the current sensor calibrated by the current sensor calibration unit.

The occurrence of torque in the motor due to an unintentional flow of the q-axis current in the motor during discharging of the smoothing capacitor is reduced. A motor control device according to the present invention controls a system including an inverter including a smoothing capacitor connected to a power source via a relay, a motor connected to the inverter, and a current sensor configured to detect a current flowing through the motor, the motor control device including: an electric discharge control unit configured to discharge, in the motor via the inverter, an electric charge accumulated in the smoothing capacitor; and a current sensor calibration unit configured to calibrate the current sensor in a state where no current in the motor flows during a time period from when the relay is cut off to when discharge control by the electric discharge control unit is started, wherein the electric discharge control unit performs discharge by controlling the current in the motor based on a value of the current sensor calibrated by the current sensor calibration unit.