摘要:
An electric coupling device for connecting, disconnecting or limiting the current in an electric circuit. The electric coupling device includes a variable resistor. This resistance is variable between a very low value corresponding to a conducting state and a very high value corresponding to a substantially insulating state. Switching between the states takes place continually and in a very short time. The invention relates to an electric circuit provided with such an electric coupling device and a method performed in accordance with the function of the electric coupling device.
摘要:
Exemplary embodiments are directed to an electrical overcurrent tripping device for a circuit breaker. The tripping device includes an actuating member which in case of an overcurrent is driven to interact directly or indirectly with a movable contact piece of the circuit breaker to open a contact point in the circuit breaker if the overcurrent is exceeding a preset tripping threshold for a predetermined tripping delay time. The actuating member is coupled to a magnetic circuit such that the driving force acting on the actuating member is created by the magnetic field of the magnetic circuit, said magnetic field being induced by the overcurrent. The actuating member is coupled to an electromagnetic damping arrangement to set the tripping delay time, and is connected to a coupling spring configured to adjust the overcurrent tripping threshold.
摘要:
The invention relates to an encapsulation system for a medium or low voltage switchgear. The switchgear includes several live phase conductors, and an encapsulation system, wherein the encapsulation system includes inner single phase encapsulations of respective phase. The encapsulation system further includes a fault handling system for handling of faults by means of adjusting the impedance of the inner single phase encapsulations.
摘要:
A Compact Secondary Substation including a fault protection system and a method for fault protection in Compact Secondary Substations (CSS). The CSS includes a Ring Main Unit (RMU), a transformer and a Low Voltage (LV) switchgear. The CSS includes a number of detectors, which detectors can be placed at least in one of the RMU, the transformer or in the LV switchgear, which detectors can be connected to a control unit, which control unit by fault detection by the detectors can activate a fast operating switch for grounding. By using the fast operating grounding switch and controlling this on the basis of the detectors placed inside the CSS, an active arc fault protection is achieved. The control unit also controls the fast operating grounding switch so that it works as a working grounding switch.
摘要:
A Compact Secondary Substation including a fault protection system and a method for fault protection in Compact Secondary Substations (CSS). The CSS includes a Ring Main Unit (RMU), a transformer and a Low Voltage (LV) switchgear. The CSS includes a number of detectors, which detectors can be placed at least in one of the RMU, the transformer or in the LV switchgear, which detectors can be connected to a control unit, which control unit by fault detection by the detectors can activate a fast operating switch for grounding. By using the fast operating grounding switch and controlling this on the basis of the detectors placed inside the CSS, an active arc fault protection is achieved. The control unit also controls the fast operating grounding switch so that it works as a working grounding switch.
摘要:
A method and a device in an electric power network (1), comprising an active filter (4) controllable via a control input (41), for reducing disturbances generated by a disturbance source (6) located in and/or connected to the power network. A control member (8) is adapted, based on at least one first state variable (Y1i) sensed in the power network (1) and a model of the power network (1), to calculate the disturbances (X2) which occur in a second section (B--B) in the power network (1) without action from the active filter (4), to calculate a control signal (C1) such that, supplied to the control input (41), it would generate in the second section (B--B) the calculated disturbances (X2) with reversed polarity, and to generate the control signal (C1) and supply this to the control input (41). By sensing, in addition, at least one second state variable (Y2i) in the second section (B--B), the control signal (C1) can also be generated in dependence on the control deviation (DU) of the second state variable (Y2i) from a desired value (Y2R). (FIGS. 1 and 2A)
摘要:
A method and a device in an electric power network (1), comprising an active filter (4) controllable via a control input (41), for reducing disturbances generated by a disturbance source (6) located in and/or connected to the power network. A control member (8) is adapted, in dependence on the control deviation (DU) from a desired value (Y2iR) of at least one state variable (Y2i) sensed in the power network (1), to generate a control signal (C1) which is supplied to the control input (41). The control member (8) is adapted to transform the control deviation (DU) in a filter device (93) with a transfer function (FI) which simulates the inverse of the transfer function (F1') from the control signal (C1) to the control deviation (DU) and/or to filter the output signal of the controller in a filter device (943, 953, 956) without any phase shift. (FIGS. 1 and 10)