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
  • 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
• • H—ELECTRICITY
  • H03—ELECTRONIC CIRCUITRY
  • H03K—PULSE TECHNIQUE
  • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
  • H03K17/16—Modifications for eliminating interference voltages or currents
• • 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
  • H01H9/54—Circuit arrangements not adapted to a particular application of the switching device and for which no provision exists elsewhere
  • H01H9/541—Contacts shunted by semiconductor devices
  • H01H9/542—Contacts shunted by static switch means

Definitions

• the invention relates to a DC switch with two terminals, between which extend an operating current path with a mechanical switch and parallel to a Maustrom- path with a semiconductor switch.
• the disconnection of a direct current (DC current) is more difficult than turning off an alternating current (AC current) for feh ⁇ lendem zero crossing. While the arc that occurs when opening the contacts, when the AC current with a suitable design in the next current zero crossing goes out, he burns in the DC current over longer distances until the destruction of the switch on.
• a general problem with switching off a DC current is that the energy stored inductively in the DC network must be reduced in such a way that damage to the components of the DC network is avoided. It is known to ⁇ USAGE for voltage-limiting elements to. But these have a limited lifespan.
• Object of the present invention is to provide a DC voltage switch, which allows an improved degradation of the inductively stored in the DC power network energy. This object is achieved by a DC voltage switch with the features of claim 1.
• the DC voltage switch according to the invention has a first and second connection for serial integration into a first pole of a DC voltage network. Between the terminals, a secondary current path with a semiconductor switch and parallel to the secondary current path extends an operating ⁇ current path with a mechanical switch and in series to the primary-side winding of a transformer.
• the secondary-side winding of the transformer is connected between a voltage source and a third terminal for integration in a second pole of the DC voltage network. Between the voltage source and the third terminal is a switch in series to the secondary winding of the
• the voltage source is also connected through a diode and a charging resistor to the first to ⁇ circuit.
• a control device for controlling the switch is provided, which is configured, after opening the mechanical switch, the voltage of the
• Voltage source is repeatedly determined and the switch so intermittently turn on, so that the determined voltage remains below a definable threshold.
• the inductively stored in the DC network power reduced in the inventive DC ⁇ switch directly on the switch. Otherwise Ele ⁇ ments for overvoltage limitation, such as varistors are unnecessary.
• the controller has switched off the switch, the voltage rises above the voltage source with time, solan ⁇ GE nor energy is inductively stored.
• the controller detects the voltage across the voltage source continuously or at intervals. If a definable threshold for the voltage which is above the operating voltage of the DC voltage network is exceeded or reached, the switch is switched on. This creates a current path from the first pole of the DC network to the second pole of the DC network. This will result in a time-limited freewheeling circuit created and the voltage at the voltage source decreases.
• the controller expediently switches the switch off again when the voltage drops below a further threshold value.
• the further threshold value may correspond to the threshold value or else be lower than the threshold value.
• the further threshold is above the operating voltage of the DC voltage network.
• the third terminal can be connected to another ground potential instead of a second pole of the DC network.
• a second resistor may be connected. This resistance is sawn vorzugt dimensioned so that at least the maximum ERS ⁇ switching current can flow at rated voltage.
• the secondary current path may comprise two antiseries switched HL-switch and the main current path, the primary side ei ⁇ nes another transformer.
• the DC voltage ⁇ switch can be designed as a bidirectional switch. In other words, the switch is thereby enabled to turn off DC in both directions. It is expedient if the secondary sides of the transformers are connected in series and that of the secondary side the transformer remote terminal of the secondary side of the further transformer is connected via a further switch to the third terminal.
• the voltage source preferably comprises an energy storage ⁇ device, in particular a capacitor. A capacitor is particularly suitable for quickly releasing the necessary energy to compensate for a short-circuit current or a normal operating current in the DC network and thus to force a zero crossing of the current.
• the power source may as a separate device may be provided with play ⁇ as a separate condenser, which work independently of other components of the Gleichputsnetz- is connected to the transformer. This can ensure a standby voltage source independent of Other pe ⁇ gen conditions, for example by a separate charging circuit for the power source.
• the voltage source can be designed as part of a further circuit, for example as an intermediate circuit capacitor of an inverter which, for example, is otherwise related to the DC network. As a result, existing resources of the structure are reused and thus achieved a total of savings on components.
• the mechanical switch can have a switching time of less than 5 ms. Because the current zero-crossing is due to the discharge of an energy storage device, the period of time within the half takes place, a current zero crossing, .rwei ⁇ se is limited to only a few milliseconds.
• the mechanical switch can open within this time to e ⁇ ⁇ ne safe suppression or erasure of the arc to be ⁇ act.
• the device may be configured such that the secondary-side winding of the transformer is short-circuited.
• the secondary-side winding of the transformer is short-circuited.
• a semiconductor switch or a fast mechanical switch provided connection between the coil ends of the secondary-side winding of the transformer.
• FIG. 1 shows a unidirectional DC voltage switch in a section of a DC voltage network
• Figure 2 a bidirectional DC voltage switch in a section of a DC network.
• FIG. 1 shows, as an exemplary embodiment of the invention, a DC voltage switch 12 in a section of a DC voltage network 10.
• the DC voltage network 10 is supplied from a DC voltage source 11 and thus supplied with a DC voltage.
• the DC ⁇ network 10 may be a network in the HVDC power supply or, for example, a network in a vehicle, such as a locomotive or a motor coach or at the inlet area in a network for electrically powered vehicles. Basically, the principle is applicable at all voltage levels from low voltage to medium voltage to high voltage.
• the DC voltage switch 12 is arranged.
• the DC voltage switch 12 is connected in series with a first and second connection terminal 121, 122 into a first pole 111 of the DC voltage network 10.
• a third connecting terminal 123 is connected to a second pole of the DC clamping voltage ⁇ network 10th
• the DC voltage switch 12 has a series connection of the primary-side winding of a transformer 14 and a mechanical switch 13. This series connection represents the main current path through which the current flows in the normal operation of the DC network 10.
• a main switch 15 is arranged in the form of an IGBT, which is a secondary current path, which is not or only slightly flows through the current during normal operation, since the IGBT also turned on a significantly higher resistance or voltage drop than the mechanical switch 13 on ⁇ points.
• the DC switch 12 further includes a freewheeling path via a freewheel diode 19 as a connection between the second and third terminal 122, 123.
• the free ⁇ running path is optional, and is then blocked if the energy stored in line inductance 1111, for example, in cables for quickly interrupted current may possibly lead to destruction.
• a further connection via a diode 163 and a charging resistor 162 to a capacitor 161 is present.
• the off-terminal of the capacitor 161 is connected to the third terminal 123.
• the potential point between the capacitor 161 and the charging resistor 162 is connected to the secondary winding of the transformer ⁇ sector 14.
• a switch 152 is arranged in the form of an IGBT, whose second terminal is connected to the third terminal 123 and thus to the second pole of the DC power network 10. In norma ⁇ len operation case, the switch is turned off and 152, so that the capacitor 161 can not discharge.
• the capacitor 161 is constantly charged in normal operation.
• the necessary voltage for the capacitor 161 and thus the exact design of the components can be determined.
• the components can be optimized, for example, for a fast off ⁇ circuit or for small sizes.
• values between 0.01 and 0.1 are suitably used.
• On the secondary side only one voltage is required, which is greater than the voltage drop across the ⁇ semiconductors to be commutated in the current, which is at a low voltage below 10V application.
• the stored energy in the grid inductance 1112 may discharge via the freewheeling diode 19.
• the energy of the line inductance in 1111 would produce a high overvoltage at the input of the DC switch ⁇ 12th
• the switch 152 is now periodically switched on and off again.
• the energy in the charging resistor 162 is converted into heat and the current flow through the network inductance 1111, diode 163 and La ⁇ dewiderstand 162 degraded.
• the switch 152 is switched off, the current can continue to flow into the capacitor 161, so that there is no rapid current drop .
• the capacitor 161 is then discharged again to limit the voltage.
• FIG. 2 A second embodiment of the invention is shown in FIG .
• the DC voltage switch 20 according to FIG. 2 is designed to be able to operate bidirectionally, ie to be able to switch off a current flow in both directions.
• Matching components of the two DC voltage switches 12, 20 are provided with the same reference numerals.
• the DC voltage switch 20 is in turn connected in series with a first and second connection terminal 121, 122 in the first pole 111 of the DC voltage network 10.
• a third terminal 123 is connected to the second pole of the DC clamping voltage ⁇ network 10th
• the DC voltage switch 20 has a series connection of the primary-side winding of the transformer 14, the mechanical switch 13 and the primary-side winding of a further transformer 24.
• This series connection represents the main current path through which the current flows in the normal operation of the DC network 10.
• Parallel to the Se ⁇ riensciens another series circuit of the main switch 15 and the anti-serially arranged further main switch 25 is arranged, which represents the Maustrompfad. pa- Rallel to the main switch 15 163 diode is connected, which may be integrated as a component in the main switch 15.
• Parallel to the other main switch 25 diode 263 maral ⁇ tet, which may be integrated as a component in the other main switch 25.
• the DC voltage switch 12 further comprises a freewheeling path via a freewheeling diode 19 as a connection between the second and third connection terminal 122, 123 and a further freewheeling path with a further freewheeling diode 191 between the first and third connection terminal 121, 123.
• the potential point between the capacitor 161 and the charging resistor 162 is connected to the secondary winding of the transformer 14 ⁇ gate. From this continuing the switch 152 is arranged, whose second terminal is connected to the third terminal 123 and thus to the second pole of the DC voltage network ⁇ 10. Between the switch 152 and the capacitor 161, a diode 271 is arranged parallel to the secondary winding of the transformer 14.
• the potential point between the capacitor 161 and the charging resistor 162 is further connected to the secondary winding of the further transformer 24.
• a further switch 252 is arranged, whose second terminal is connected to the third terminal 123 and thus to the second pole of the DC network 10.
• a diode 272 is arranged parallel to the secondary winding of the further transformer 24.
• the bidirectional DC voltage switch 20 comprises two anti-series connected unidirectional DC voltage switches 12, the elements of mechanical switch 13, charging resistor 162 and capacitor 161 being needed only once.
• the pulse generation by the switch 152 and the transformer 14 is used for the generation of the commutation voltage and for the reduction of the energy in the grid inductance 1111.
• Free-wheeling diode 19 serves to reduce the energy in the network inductance 1112.
• the pulse generation by the further switch 252 and the further transformer 24 is used for the generation of the commutation voltage and for the reduction of the energy in the network inductance 1112.
• the freewheeling diode 191 is used to reduce the energy in the network inductance 1111.
• the two diodes 271, 272 parallel to the secondary windings of the transformers 14, 24 serve as a freewheeling circuit for the leakage inductances and can also be replaced by resistors, analogous to the unidirectional DC voltage switch 12th

Landscapes

• Engineering & Computer Science (AREA)
• Power Engineering (AREA)
• Dc-Dc Converters (AREA)
• Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=58358593

Family Applications (1)

Country Status (7)

Families Citing this family (5)

Family Cites Families (12)

• 2016
  • 2016-03-17 DE DE102016204400.1A patent/DE102016204400A1/de not_active Withdrawn
• 2017
  • 2017-03-16 RU RU2018134021A patent/RU2703190C1/ru not_active IP Right Cessation
  • 2017-03-16 CN CN201780017950.7A patent/CN108781075A/zh active Pending
  • 2017-03-16 WO PCT/EP2017/056224 patent/WO2017158082A1/de active Application Filing
  • 2017-03-16 EP EP17711631.6A patent/EP3414838A1/de not_active Withdrawn
  • 2017-03-16 KR KR1020187029924A patent/KR20180122003A/ko active IP Right Grant
  • 2017-03-16 US US16/084,484 patent/US20190074149A1/en not_active Abandoned

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