A method and an apparatus for controlling a circuit breaker in an electrical energy supply network. A switching signal is generated by a protective or control device of the energy supply network and the switching signal is transmitted to a control unit of the circuit breaker. The control unit is caused to open the switching contacts of the circuit breaker upon reception of the switching signal. In order to ensure a switching operation which is as fast as possible even in those energy supply networks in which phases of the current to be switched by a circuit breaker which are free of zero crossings can occur, a current flowing through the circuit breaker is recorded and is checked for the occurrence of zero crossings. The transmission of the signal for opening the switching contacts is prevented until at least one zero crossing has been detected.

The switching apparatus and the method are for varying the impedance of a phase line of a segment of an electrical power line. The phase line includes n conductors electrically insulated from each other and short-circuited together at two ends of the segment. The apparatus comprises a controllable interrupter connected in series for each conductor; a parameter detector; a first controller for controlling the interrupters; and a disabling unit for disabling the interrupters. The disabling unit comprises n controllable switches associated with the interrupters, position detectors for detecting which of the interrupters is closed, and a second controller having a command output to command the controllable switches and ensure that, at all operating times, at least one of the interrupters is closed and disabled.

A current sensing assembly includes a conductor having a first side, a second side opposite the first side, a third side, and a fourth side opposite the third side. The first side has a first notch formed therein and the second side has a second notch formed therein opposite the first notch. The current sensing assembly also includes a sensor assembly including a first magnetic sensor disposed in the first notch or proximate to the third side of the conductor between the first and second notches, and a second magnetic sensor disposed in the second notch or proximate to the fourth side of the conductor between the first and second notches.

The invention relates to a switching device for a MV electric power distribution network. The switching device comprises electric contacts, which are electrically connectable to a conductor of said electric power distribution network, and a control unit. The switching device comprises signalling means emitting visible light externally to said switching device, said signalling means being controlled by said control unit.

The circuit breaking system contains a power circuit whose voltage is greater than 600 volts, at least a circuit breaking device, at least a current detection device, a current reduction unit, at least an actuation device, and a linking device. The circuit breaking system is applicable to a high or ultra-high voltage power circuit, and the power circuit is interrupted through purely mechanical means without additional electricity provision. Even when there are major disasters that existing protection means fails, the present invention can still function and provides a trip free, ultimate self-protection mechanism so that a power system can be readily reset.

An electric device comprises a first and second voltage sensor, a current sensor, an actuator and a controller. The first voltage sensor senses a first voltage at a first contact of a switch inside the electric device and generates a first voltage signal indicating the first voltage, the first contact of the switch coupled to a source line. The second voltage sensor senses a second voltage at a second contact of the switch and generates a second voltage signal indicating the second voltage, the second contact is coupled to a reactive component. The current sensor senses a current at the second contact of the switch and generates an output signal indicating the current. The controller is coupled to the voltage sensors, the current sensor and the actuator and causes, based on at least one of the voltage and current signals, the actuator to actuate one of the contacts to execute switching at a predetermined point of the first voltage.

The circuit breaking system contains a power circuit whose voltage is greater than 600 volts, at least a circuit breaking device, at least a current detection device, a current reduction unit, at least an actuation device, and a linking device. The circuit breaking system is applicable to a high or ultra-high voltage power circuit, and the power circuit is interrupted through purely mechanical means without additional electricity provision. Even when there are major disasters that existing protection means fails, the present invention can still function and provides a trip free, ultimate self-protection mechanism so that a power system can be readily reset.

An insulated switchgear module is disclosed. In one example, the module comprises a vacuum interrupter, current exchange assembly, and end conductors disposed within an insulated housing. The insulated housing further comprises a tank containing an actuator mechanism for actuating the current exchange assembly. An insulating tray within the housing separates the vacuum interrupter from the components in the tank. The insulated tray has a shape that corresponds with the shape of the vacuum interrupter and the shape of the housing.

A method and a system (9) for testing a switching installation (30) for power transmission installations are provided. The switching installation (30) comprises a switch (2) which either connects a first side (6) of the switch (2) to a second side (7) of the switch (2) or disconnects it therefrom, and comprises two earthing switches (10, 11). Each of the two earthing switches (10, 11) is provided to either connect the first side (6) or the second side (7) to earth (1) or to disconnect it from earth (1). To test the switching installation (30), a current is generated through the switch (2) and a magnitude of the current through the switch (2) is determined. In this respect, the two earthing switches (10, 11) are closed while the current is generated and while the magnitude of the current is determined.

A voltage and/or current sensing device for low-, medium- or high voltage switching devices is disclosed as a constructively enhanced measuring device with high performance for use in switching devices. The sensing device can include a first voltage sensing part, a second voltage sensing part and a current sensing part all arranged in a same common single housing separated, from the switching device, in a way that an output wire from the first voltage sensing part, for sensing voltage at an upper terminal of the switching device, is located close to the current sensing part, the output wire being applied with an insulating cover, and mechanically fixed to the current sensor part, and/or the output wire being implemented in an isolation body, and only located near to the current sensing part.