Classifications

• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H9/00—Details of switching devices, not covered by groups H01H1/00 - H01H7/00
  • H01H9/30—Means for extinguishing or preventing arc between current-carrying parts
  • H01H9/44—Means for extinguishing or preventing arc between current-carrying parts using blow-out magnet
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
  • H01H33/00—High-tension or heavy-current switches with arc-extinguishing or arc-preventing means
  • H01H33/02—Details
  • H01H33/59—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the AC cycle
  • H01H33/596—Circuit arrangements not adapted to a particular application of the switch and not otherwise provided for, e.g. for ensuring operation of the switch at a predetermined point in the AC cycle for interrupting DC

Definitions

• the present invention relates to an arc extinguishing aid with an externally supplied magnetic blow coil for switching small currents.
• DC circuit breakers such as tie switches and line and rectifier switches are used in DC networks of electrical railways, etc. for different tasks, with a different profile of requirements with regard to guiding and switching in two current directions.
• Section switches must carry and switch currents in both current directions, and section and rectifier switches can in the case of one
• the arc can be viewed as a current-carrying conductor on which a force is exerted when it encounters a magnetic field.
• an external magnetic field can be applied to increase the arcing.
• This field can be realized, for example, by magnetic blow coils connected in series in a main circuit. These are either constantly flowed through by the main current or energized during an extinguishing process if, for example, probes are connected to the main circuit via coils.
• the invention is therefore based on the object to solve the problems mentioned above and to provide an inexpensive and universally usable arc extinguishing aid.
• this object is achieved by an arc-quenching aid, as set out in claim 1.
• a coil fed by a control voltage network which generates a magnetic field, the field lines of which penetrate the arc perpendicularly and whose field direction changes based on the control by the circuit for detecting the current direction.
• the magnetic field causes an interaction with the arc current Long of the bow and drifts from the contacts of the
• the hearing of the magnetic field generated by the externally supplied coil is independent of the current level of the main circuit. In the case of very small currents, for example 1A, this is sufficient for the elongation
• Magnetic field available There is no need for coils that have a high short-term current carrying capacity and are expensive, and there are also no thermal losses due to elements connected to the main circuit.
• the invention is based on a
• FIG. 2 shows a DC circuit breaker in which the arc-extinguishing aid according to the invention is used
• Fig. 3 is a block diagram of the evaluation circuit shown in Fig. 1.
• FIGS. 1 to 3 An exemplary embodiment of an arc-quenching aid according to the invention for switching small currents is described in more detail with reference to FIGS. 1 to 3.
• reference numeral 2 denotes a changeover switch or cross switch, 3 a magnetic blow coil, 5 a switch, 6 a storage capacity and 7 an evaluation circuit for
• FIG. 2 Hall sensors 1 the magnetic blow coil 3, an iron circuit 4, a movable contact piece 8 and a fixed contact piece 9 of a DC circuit breaker and an upper busbar 10 of the main circuit are shown.
• the reference numeral 11 denotes the fixed side of an arc conductor, 12 an insulation of the iron core, 13 an insulation of the coil, 14 a side wall of a quenching plate arrangement, 15 the movable side of the arc conductor, 16 a pre-contact and 17 a flexband of the DC circuit breaker.
• the sensitive Hall sensors 1 for current direction detection are arranged for measuring the current in the main circuit of the DC circuit breaker. To reduce the interference, it is expedient to position the Hall sensors 1 at a short distance from one another. To further increase the immunity to interference, the two Hall sensors 1 are positioned in such a way that the useful field of both sensors is the same in amount but opposite in direction. When the signals from the Hall sensors 1 are subtracted in the evaluation circuit 7 described in more detail below, interference signals are thus filtered out. Since the conductors in the main circuit have a predetermined large cross section owing to their current carrying capacity (several kA), the Hall sensors 1 can be embedded in the upper busbar 10, as shown in FIG. 2, thereby minimizing the circuit scope.
• the evaluation circuit 7 consists of the Hall sensors 1 and 2, each of which is followed by an amplifier and a balancer.
• the output signals of the Comparators are fed to a subtractor, which
• the comparator uses a threshold value to check whether the signal supplied to it is greater than zero or not, and outputs a signal to a downstream amplifier in accordance with the test result.
• the amplifier thus outputs a signal that is proportional to the detected current direction.
• This signal controls the cross switch 2, which changes the polarity or current flow direction in the magnetic blowing coil 3, by switching between contacts a and b in FIG. 3.
• the evaluation circuit 7 must therefore before actuating an auxiliary trigger of the DC circuit breaker
• Switch off be active.
• the evaluation circuit 7 could, however, also become active in the case of a switch-off command if the DC circuit breaker is opened with a slight time delay for detecting the current direction.
• the switch 5 is closed in parallel.
• the discharge of the capacitor 6 is thus initiated via the magnetic blowing coil 3.
• the magnetic field thus generated by the coil is guided in a targeted manner via the iron circuit 4 to the arc area at the contacts 8 and 9 of the DC circuit breaker, in particular to the base area of the arc.
• Various experiments have shown that magnetic field blowing in this area extremely effectively causes the arc to wander or run.
• the capacitance 6 also serves as a load buffer, which is charged when the switch 5 is open, so that the above described system even if the auxiliary voltage fails or
• the advantages of the invention include in that the magnitude of the magnetic field generated by the magnetic blowing coil is independent of the current level in the main circuit and therefore a magnetic field sufficient for elongation is available for very small currents of 1A, for example.
• no coils are required, which must have a high short-term current carrying capacity (lOOOOOA) and are expensive, and there are no thermal losses due to elements connected in the main circuit.
• an arc-quenching aid with an externally supplied magnetic blowing coil for switching small currents in which the current direction in the externally supplied magnetic blowing coil is switched based on the detection of the current direction in the main circuit of a DC circuit breaker.

Landscapes

• Arc-Extinguishing Devices That Are Switches (AREA)
• Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
• Measurement Of Current Or Voltage (AREA)
• Geophysics And Detection Of Objects (AREA)

Applications Claiming Priority (3)

Publications (2)

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ID=7903183

Family Applications (1)

Country Status (11)

Families Citing this family (8)

Family Cites Families (12)

• 1999
  • 1999-03-31 DE DE19914773A patent/DE19914773B4/de not_active Expired - Lifetime
• 2000
  • 2000-03-31 EP EP00929336A patent/EP1099232B1/fr not_active Expired - Lifetime
  • 2000-03-31 US US09/701,592 patent/US6683764B1/en not_active Expired - Lifetime
  • 2000-03-31 AU AU47462/00A patent/AU4746200A/en not_active Abandoned
  • 2000-03-31 DE DE50014565T patent/DE50014565D1/de not_active Expired - Lifetime
  • 2000-03-31 PL PL348430A patent/PL197384B1/pl not_active IP Right Cessation
  • 2000-03-31 KR KR1020007013475A patent/KR100694954B1/ko not_active Expired - Fee Related
  • 2000-03-31 WO PCT/EP2000/002914 patent/WO2000065624A2/fr not_active Ceased
  • 2000-03-31 EA EA200001243A patent/EA002786B1/ru not_active IP Right Cessation
  • 2000-03-31 CN CNB008003904A patent/CN1199210C/zh not_active Expired - Lifetime
  • 2000-03-31 SK SK1662-2000A patent/SK286408B6/sk not_active IP Right Cessation
  • 2000-03-31 AT AT00929336T patent/ATE370510T1/de not_active IP Right Cessation

Non-Patent Citations (1)

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