SU1111211A1 - D.c.circuit breaker - Google Patents

Abstract

1. A DC switch, containing a vacuum arcing chamber, shunted by an damping circuit composed of an auxiliary key element, a precharged switching capacitor, an inductive-dynamic coil of a contact opening opening of a vacuum arcing chamber, a nonlinear resistor, an auxiliary coax unit, and a diode circuit, and a diode unit, and a diode unit and a non-linear resistor, a diode circuit, and a diode unit, and a non-linear resistor, a diode circuit, and a diode unit, and a non-linear resistor, a diode circuit, and a diode unit, and a non-linear resistor, a diode circuit, and a diode unit, and a non-linear resistor, a diode circuit, and a diode unit, and a diode unit, and a diode unit, and a non-linear diode circuit, and a diode pattern, and a diode unit, and a diode unit, and a diode unit that has a diode pattern and a non-triggered device and a diode unit that has a diode switch and a diode unit that has a diode circuit, a nonlinear resistor, an auxiliary switch, and a non-linear resistor; the fact that, in order to extend the functionality by disabling the forward and reverse currents and increasing Servicing implications, an induction-dynamic drive coil for opening the contacts of the vacuum arcing chamber and a precharged capacitor are connected in series to the diagonal of the additionally introduced bridge consisting of four key elements in the form of thyristors shunting the contacts of the vacuum arcing chamber, which are blocking diodes and the extinguishing resistor. connected to the minus of the power supply, and to the diagonal of the bridge from the minus side of the pre-charged switching condensate a and $} atodov attached thereto a chain of thyristors connected in series, § consisting of trip coil additionally introduced auxiliary (A Foot switch and its power contacts, and the current-limiting resistor, the other end is connected to minus power supply. 2. A switch according to claim 1, characterized in that the auxiliary switch is made three-pole, and its two other contacts are connected to the power circuit sequentially through the contacts of the vacuum arcing chamber. 3. The switch on the PP. 1 and 2, characterized in that the damping resistor is non-linearly fulfilled.

Description

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The invention relates to electrical engineering, and more specifically to switching devices of direct current with vacuum interrupter chambers.

Known switch, which contains the main vacuum arcing chamber, auxiliary key, the element in the form of an additional vacuum arcing chamber or thyristor, as well as a pre-charged switching capacitor connected in series with the key element and the coil of the induction-dynamic actuator for opening the contacts of the main vacuum chamber 1.

The shutdown arc in the main vacuum arc chamber of such a switch is extinguished only when a current flows in one direction through its contacts and if there is a counter-current of the switching capacitor to the shutdown current. Current limitation occurs after recharging the commutating capacitor, and the disconnection ends after transferring to the capacitor almost all the energy of the magnetic field stored in the switching circuit, which leads to significant overvoltages.

Closest to the proposed technical essence and the achieved result is a DC switch containing a vacuum arcing chamber, shunted by a damping circuit composed of an auxiliary key element, a precharged switching capacitor, an inductive-dynamic coil of a contact opening of a vacuum arc extinguishing chamber, non-linear resistor, auxiliary switching device and diode blocking 2 ..

The disadvantages of this device are its functional limitations due to the inability to turn off the reverse currents in the power circuit through the contacts of the vacuum interrupter chamber, the low level of safety during maintenance and the inability to use it in protective shutdown systems as a result of the absence of a real circuit breakdown. security.

The purpose of the invention is to expand the functionality by

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disconnecting forward and reverse currents and increasing service safety.

The goal is achieved by the fact that in a switch of direct current containing a vacuum arcing chamber shunted by an damping circuit composed of an auxiliary key element, a precharged switching capacitor, an inductive-dynamic coil of a contact opening of a vacuum arcing chamber, a nonlinear resistor, an auxiliary switch device and diode-blocking, induction-dynamic drive of opening the contacts of the vacuum interrupter Cameras and a pre-charged capacitor are included in the diagonal of an additionally introduced bridge consisting of four key elements in the form of thyristors shunting the contacts of the vacuum arc chamber, which are connected to the negative side of the power supply through the blocking diodes and the damping resistor on the minus side of the pre-charged switching capacitor and the cathodes of the thyristors connected to it, a series of circuits is connected ki additionally entered the auxiliary switch and its power contacts, and the current-limiting resistor, the other end is connected to minus power supply.

The auxiliary switch is triple-pole, and its other two contacts are connected in series to the power circuit through the contacts of the vacuum interrupter chamber.

The damping resistor is non-linear.

The drawing shows the circuit diagram of the switch.

The switch contains a vacuum arcing chamber 1 to which contacts 2 and 3 of the two poles of a three-pole auxiliary air switchgear are connected in series on the anode and cathode side, between which Moct is connected parallel to the contacts of the vacuum arc extinguishing chamber 1, consisting of four key elements in the form of thyristors 4- 5 and 6-7 respectively3

in each shoulder of the bridge. A coil 8 of an inductively dynamic drive is connected in series to the bridge diagonal, which is used to open the contacts of the vacuum arcing chamber 1 and a precharged switching capacitor 9. A series of three-pole tripping coil 10 is connected to the bridge diagonal on the minus side of the extinguishing capacitor 9 auxiliary air switch and its third pole 11, one of the contacts of which is connected to the minus of the power source. The circuit breaker uses an extinguishing resistor consisting of two parts, with part 12 connected to the source minus and part 12 to the anodes of blocking diodes 13 and 14, each of which is connected by a cathode to the corresponding contact of the vacuum arc chamber 1 at the points of thyristor 4 -5 and 7-6, respectively.

The switch works as follows.

In the on position of the cones of the vacuum arcing chamber 1 and the contacts 2 and 3 of the auxiliary three-pole air switch, the current can flow through them in both the forward and reverse directions. In both cases, when a command to disconnect from the control circuit is received, thyristors 5 and 7 are switched off during forward current, or thyristors 4 and 6 during reverse flow, while the precharged switching capacitor 9 is discharged in the circuit through the contacts of the vacuum arcing chamber 1 and coil 8 induction-dynamic drive of their opening. In a transient disconnection mode, the current flows from the contacts of the vacuum chamber 1 to the switching capacitor 9, which then recharges and disconnects the load circuit from the source. To facilitate the tripping process, the current in the source circuit is briefly switched to a nonlinear current-limiting resistor 12, which, when the current flows, increases the shearing resistance and thereby facilitates the process of opening the circuit that shunts the source for the duration of the trip. With this current, limited

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part of the nonlinear resistor 12,

flows through pins 2 and 11) n: and of a powerful three-pole air switching unit, the third pole 3 of which also opens simultaneously with the contacts of the other two poles and, in addition to extinguishing resistor, carries out the quenching of magnetic energy, the reserve circuit of the disconnected. The nonlinear dependence of the active resistance of the nonlinear resistor part 12 on the flow time and the amount of current to be switched off in the circuit makes it easier: the switching process is due to the smoothness of its growth. When the forward and reverse currents are disconnected, the opening of the contacts 2, 3 and 11 of the auxiliary switching device occurs after the flow-.

 current to the breaking coil 10

which causes the opening drive of the apparatus to be triggered with some delay relative to the moment of opening of the contacts of the vacuum interrupter chamber 1. The shutdown process ends with extinguishing — the arc of the auxiliary three-pole air commutation apparatus due to the flow of current through a part of the non-linear cut-off. Torah. The reverse current is also disconnected in the same way, with contact 2 becoming extinguished, and contact 3 breaking.

5 The switch is not polarized and provides fast-acting disconnection of both direct and reverse currents of traction load and short circuits in the power supply circuits of contact networks with two-sided power at voltages of 275, 600 and 850 V. The switch can be used for protect semiconductor converters as well

 for partitioning contact networks. The installation of such switches on the rolling stock provides the ability to switch the circuit n recovery modes. High tacitability and fastness; the action of the switch is provided by the presence of a shunt circuit with arcless contact switching by the arc arcing chamber, and

5 also by the presence of a current-limiting and quenching part of a non-linear resistor, which provides a significant increase in active resistance during short-term current flow at the moment of source shunting and the circuit being disconnected. The reliability of the current shutdown combined by the switching system is ensured by the presence of an auxiliary three-pole air circuit breaker, the shutdown current of which corresponds to the protection actuation setting. The switch provides a real visible break of the current circuit and fully meets the requirements of safety engineering during operation and repair in underground conditions.

Claims (3)

1. A DC switch containing a vacuum arrester shunted by a quenching circuit composed of an auxiliary key element, a pre-charged switching capacitor, an induction-dynamic drive for opening the contacts of the vacuum arcing chamber, a nonlinear resistor, an auxiliary switching device and diode blocking, characterized in that , in order to expand functionality by disabling direct and. reverse currents and improving the safety of service, an induction-dynamic drive of breaking the contacts of the vacuum interrupter chamber and a pre-charged capacitor are connected sequentially to the diagonal of the additional bridge, consisting of four key elements in the form of thyristors, bypassing the contacts of the vacuum arrester chamber, which the blocking diodes and the quenching resistor are connected to the minus of the power source, and to the diagonal of the bridge from the minus side is pre-charged th commutating capacitor and the cathodes of the thyristors connected thereto connected serial chain consisting of a trip coil additionally introduced auxiliary switch and its power contacts, and the current-limiting resistor, the other end connected to negative power source. 2. The switch according to claim 1, characterized in that the auxiliary switch is tri-pole, and its other two contacts are connected in series through the contacts of the vacuum interrupter chamber. 3. The switch according to paragraphs. 1 and 2, characterized in that the quenching resistor is made non-linear. SU „„ 1111211 1,111