A method and a circuit for detecting an electric arc in an electric circuit supplied with AC current during a supply period includes measuring at least one input signal (S) among a current (I) and an input voltage (U) of the electric circuit, supplying a warning signal (A1) to indicate that an electric arc occurs when the input signal (S) is constant over at least one portion of the supply period, digitally sampling the input signal (S) during the measurement thereof according to predetermined levels and, to identify that the input signal (S) is constant, determining the frequency at which each level is reached by the input signal (S) over a predetermined time window, comparing the frequency of each level with a predetermined warning threshold, and issuing the warning signal if the frequency of at least one of the levels is higher than the warning threshold.

An arc detection assembly is provided and includes first and second conductors including first and second terminal ends, respectively, which are engageable to form an electrical connection and a temperature sensing system. The temperature sensing system includes a temperature sensor disposed in contact with one of the first and second terminal ends and configured to sense a temperature of the one of the first and second terminal ends and a temperature monitoring circuit. The temperature monitoring circuit is coupled to the temperature sensor and configured to determine when the temperature sensor senses an increase in temperature of the one of the first and second terminal ends and to determine whether the increase in temperature is indicative of an arcing condition of the electrical connection.

An arc detection assembly is provided and includes first and second conductors including first and second terminal ends, respectively, which are engageable to form an electrical connection and a temperature sensing system. The temperature sensing system includes a temperature sensor disposed in contact with one of the first and second terminal ends and configured to sense a temperature of the one of the first and second terminal ends and a temperature monitoring circuit. The temperature monitoring circuit is coupled to the temperature sensor and configured to determine when the temperature sensor senses an increase in temperature of the one of the first and second terminal ends and to determine whether the increase in temperature is indicative of an arcing condition of the electrical connection.

An intelligent integrated medium-voltage alternating current (AC) vacuum switchgear based on a flexible switching-closing technology comprises a controller (24), and a vacuum switching tube (1), an insulator (9), and an switching-closing mechanism connecting piece (15), which are connected in sequence. A microprocessor is built in an intelligent circuit (23); a travel sensor is fixed to a movable contact connecting rod (5), and directly detects a motion state of a movable contact (4) and acquires accurate motion parameters of the movable contact (4); switching-closing operating parameters are obtained by comprehensively calculating arc light intensity detected by an arc light transmitter (20) and a temperature measured by an infrared temperature measuring transmitter (22), such that the switching-closing performance of switching on and switching off a medium-voltage power grid is greatly improved, switching-closing time points can be accurately controlled, and flexible switching-closing is achieved.

An intelligent integrated medium-voltage alternating current (AC) vacuum switchgear based on a flexible switching-closing technology comprises a controller (24), and a vacuum switching tube (1), an insulator (9), and an switching-closing mechanism connecting piece (15), which are connected in sequence. A microprocessor is built in an intelligent circuit (23); a travel sensor is fixed to a movable contact connecting rod (5), and directly detects a motion state of a movable contact (4) and acquires accurate motion parameters of the movable contact (4); switching-closing operating parameters are obtained by comprehensively calculating arc light intensity detected by an arc light transmitter (20) and a temperature measured by an infrared temperature measuring transmitter (22), such that the switching-closing performance of switching on and switching off a medium-voltage power grid is greatly improved, switching-closing time points can be accurately controlled, and flexible switching-closing is achieved.

Disclosed is a device for recognizing an arcing fault in incident light, comprising a sensor for detecting absorption lines of the incident light, and an evaluation unit which generates an evaluation signal then characteristic absorption lines are detected.

A gas-insulated switching apparatus of a three-phase-isolated type includes: two first main buses and extending in parallel at an identical height; a first connection bus interconnecting the first main buses; a first divergence bus diverging downward from the first connection bus; and a first circuit breaker connected to the first divergence bus, wherein a connection portion between the first connection bus and the first divergence bus is disposed at a position lower than the height at which the first main buses extend, and a grounding switch is disposed above the connection portion between the first connection bus and the first divergence bus.

A gas-insulated switching apparatus of a three-phase-isolated type includes: two first main buses and extending in parallel at an identical height; a first connection bus interconnecting the first main buses; a first divergence bus diverging downward from the first connection bus; and a first circuit breaker connected to the first divergence bus, wherein a connection portion between the first connection bus and the first divergence bus is disposed at a position lower than the height at which the first main buses extend, and a grounding switch is disposed above the connection portion between the first connection bus and the first divergence bus.

An electric arc detection device samples first, second and third filterings of a signal in a current window and in another window. A correlation is determined between first filtering samples of the current and the other window, a correlation is determined between second filtering samples of the current and the other window, and a correlation is determined between third filtering samples of the current window and the other window. An arc is then detected as a function of the correlations.

In an embodiment, an arc light sensor includes: a first polarizer, a second polarizer, a magneto-optical material, a first light filter and a processing unit. The first polarizer is used for polarizing incident first target light, to form first polarized light in a first polarization direction. The second polarizer is used for polarizing incident second target light, to form second polarized light in the first polarization direction. The magneto-optical material, in a current magnetic field, uses the current magnetic field to rotate a polarization direction of the first polarized light, to form third polarized light. The first light filter is used for filtering the third polarized light, to form fourth polarized light capable of passing in a second polarization direction. The processing unit is used for determining whether the second target light is arc light according to intensity of the second polarized light and intensity of the fourth polarized light.