The invention relates to an electric circuit arrangement (20) for the functional testing of a monitoring device (4) for a power supply system (2), the electric circuit arrangement (20) having a test resistance (R.sub.f1, R.sub.f2) which is switched between an active conductor (L.sub.1, L.sub.2) of the power supply system (2) and ground (PE) and has a settable actual resistance value (R.sub.x). In this context, a bidirectional cascade (12) consisting of field-effect transistors as test resistances (R.sub.f1, R.sub.f2) and an analog control (10) for the continuous-value setting of the actual resistance value (R.sub.x) to a predefined target resistance value (R.sub.0) are provided. Furthermore, the invention relates to a modular circuit arrangement (60) consisting of several electric circuit arrangements (20) according to the invention, each of the electric circuit arrangements (20) being assigned a different active conductor (L.sub.1, L.sub.2) of the electric power supply system (2), and a central control unit (50) being implemented for controlling and monitoring the electric circuit arrangements (20).

A test apparatus for testing a cable assembly includes a first air tightness tester, a second air tightness tester and an electrical tester. A first test device is operably connected to the first air tightness tester and the electrical tester, and a second test device is operably connected to the second air tightness tester and the electrical tester. With a first cable connector and a second cable connector of a cable installed on a respective one of the first test device and the second test device, an air tightness test and an electrical test are performed on the first cable connector and the second cable connector simultaneously.

A DC electrical network intended to supply electricity to an electrical load via an electric power source. A first pole of the electric power source is linked to first ends of two first electrical lines, second ends of which are linked to one another, and also to a first pole of the electrical load via two stages of a contactor. A second pole of the electric power source is linked to first ends of two second electrical lines, second ends of which are linked to one another, and also to a second pole of the electrical load via two other stages of the contactor. The electrical network further comprises a processing unit configured to control the contactor to open if current measurements correspond to currents flowing in opposite directions through the two first electrical lines or through the two second electrical lines.

The present disclosure provides a method for detecting an electrical discharge in an electrical apparatus. The method includes sensing an electromagnetic wave using an electrical sensor and generating an electric signal for a predetermined time period, sensing an acoustic wave using an acoustic sensor and generating an acoustic signal for the predetermined time period. The acoustic sensor is associated with at least one compartment of the electrical apparatus. Electrical data is generated based on a quasi-periodic characteristic of electric peak sequences of the electrical signal. Acoustic data is generated based on a quasi-periodic characteristic of acoustic peak sequences of the acoustic signal, wherein the electrical data is combined with the acoustic data to provide an operation status of the at least one compartment.

Techniques, systems and articles are described for monitoring electrical equipment of a power grid and predicting likelihood failure events of such electrical equipment. In one example, a cable accessory is configured to couple to an electrical power cable and includes a partial discharge sensor and a communications unit. The partial discharge sensor is configured to detect partial discharge events and output data indicative of the partial discharge events. The communications unit is configured to output event data based at least in part on the partial discharge data.

The present invention discloses an insulation detection circuit and a detection method thereof for a two-way on-board charger. The detection circuit comprises an inverter circuit, a first Y capacitor connected between an output live line and a ground line of the inverter circuit, a second Y capacitor connected between an output neutral line and the ground line of the inverter circuit, a live line sampling circuit and a neutral line sampling circuit which are connected with the output live line and the output neutral line of the inverter circuit, and a controller. The controller determines an insulation state of the two-way on-board charger according to two sampling voltages.

An arc detection device is used in a system including one or more power sources, a plurality of converters, and a plurality of load devices. The one or more power sources and the plurality of converters are connected to each other by a plurality of power lines. The plurality of converters and the plurality of load devices are connected to each other by a plurality of power lines. The arc detection device includes: an electric current detector that includes a magnetic core through which two or more power lines included in the plurality of power lines extend, and detects combined currents flowing through the two or more power lines according to the magnetic field produced at the magnetic core; and an arc determiner that determines, on the basis of the combined currents detected by the electric current detector, whether an electric arc has occurred.

A method for detecting an abnormal event in an insulator of an electrical conductor of a medium-voltage or high-voltage electrical device. The method includes: acquiring a set of successive samples of a vibration signal associated with the electrical conductor; determining a modelled value of a following sample based on the acquired set of samples and on a prediction model, the prediction model being obtained through machine learning of the vibration signal based on a set of samples acquired in reference conditions in which the electrical conductor is free from any abnormal event; acquiring the following sample of the vibration signal; calculating a difference between the value of the acquired sample and the modelled value; and if the calculated difference is greater than a predetermined threshold, detecting an abnormal event in the electrical conductor.

A method for classifying a partial discharge in an insulator of an electrical conductor of a medium voltage or high voltage electrical device, the method allowing a partial discharge to be classified from between at least one first class and a second class distinct from the first class. The method includes: obtaining a set of samples each corresponding to at least one partial discharge, determining a classification model by automatic learning based on at least one statistical quantity of the samples of the set, acquiring a new sample corresponding to at least one partial discharge, and determining the class of the partial discharge associated with the new sample acquired using the classification model.

The invention relates to an optical insulation monitoring device for power cables, having at least one optical waveguide for transmitting an optical signal integrated into a polymer film. The polymer film is arranged in such a way that the radially outer surface of the cable is surrounded by the polymer film in at least one longitudinal portion of the cable. At least some of the optical waveguides can be designed as multimode waveguides. The optical waveguides may be integrated in a plurality of layers in the polymer film, the optical waveguides of a first layer being arranged in staggered fashion with respect to the optical waveguides of a second layer arranged above or below the first layer. In this way, at least a section of the polymer film in the film plane is completely covered by the optical waveguides without any unwanted crosstalk between adjacent optical waveguides resulting.