Improved PT monitoring and switching device in mining explosion-proof high-voltage power distribution device

Abstract

The utility model discloses an improved PT monitoring switching device in a mining explosion-proof high-voltage power distribution device, which comprises an intermediate relay, a voltage relay, a knob switch and a signal indicating lamp, and is characterized in that a coil of the voltage relay is respectively connected among a secondary side AB phase, a secondary side BC phase and a secondary side LN phase of a PT of a circuit breaker; an auxiliary normally open contact of the voltage relay and the knob switch are connected in parallel and then are connected in series with a coil of the intermediate relay between a secondary side AB phase of the PT of the circuit breaker; an auxiliary normally open contact of the intermediate relay and the signal indicating lamp are connected in series between the secondary side AB phase of the PT of the circuit breaker; an auxiliary normally open contact of the intermediate relay is connected in series to a special bus PT loop; and an auxiliary normally-closed contact of the intermediate relay is connected in series to a PT loop of the circuit breaker. The high-voltage circuit breaker has the advantages that switching between the PT of the high-voltage circuit breaker and the PT special for the bus can be achieved, the fault monitoring function of the PT of the circuit breaker can be achieved, and the power supply reliability is improved.

Description

Technical field:

[0001] The utility model relates to the field of flameproof high-voltage power distribution devices for mines, in particular to an improved PT monitoring switching device in flameproof high-voltage power distribution devices for mines. Background technology:

[0002] At present, for the convenience of use, each high-voltage circuit breaker feeder cabinet in the coal mine is equipped with a PT. However, due to insufficient space in the cabinet, there is no built-in PT in the fuse-contactor circuit. When the high-voltage distribution device is fixedly installed in the coal mine underground substation, in order to meet the needs of various feeder cabinets, a dedicated PT cabinet needs to be set up on the high-voltage bus. At present, this wiring method has the following main disadvantages: (1) A PT parallel switching function is set between the bus-specific PT cabinets, but the circuit breaker feeder cabinet does not lead the PT device signal line from the bus-specific PT, and cannot realize the parallel switching between the built-in PT and the bus-specific PT; (2) Once a problem occurs with the built-in PT of the circuit breaker feeder cabinet, it cannot be discovered in time and the bus-specific PT signal cannot be input, affecting the power supply reliability. Utility model content:

[0003] The purpose of the utility model is to provide an improved PT monitoring switch device in a flameproof high-voltage power distribution device for mines to solve the above-mentioned problems and shortcomings. The device greatly improves the safety and reliability of the power supply system in coal mines.

[0004] The utility model is implemented by the following technical scheme: an improved PT monitoring switching device in a flameproof high-voltage power distribution device for mining, which also includes an intermediate relay, three voltage relays, a knob switch and a signal indicator light. The coils of the three voltage relays are respectively connected between the secondary side AB phase, BC phase and LN phase of the PT provided by the circuit breaker; after the auxiliary normally open contacts of the three voltage relays and the knob switch are connected in parallel, they are connected in series with the coil of the intermediate relay between the secondary side AB phase of the PT provided by the circuit breaker; an auxiliary normally open contact of the intermediate relay and a signal indicator light are connected in series between the secondary side AB phase of the PT provided by the circuit breaker; the four auxiliary normally open contacts of the intermediate relay are connected in series to the busbar dedicated PT circuit; the four auxiliary normally closed contacts of the intermediate relay are connected in series to the PT circuit provided by the circuit breaker.

[0005] The utility model has the advantages that the utility model can switch between the built-in PT of the high-voltage circuit breaker and the dedicated PT of the busbar, and can realize the fault monitoring function of the built-in PT of the circuit breaker, thereby improving the power supply reliability. Description of the drawings:

[0006] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0007] Figure 1 It is a circuit schematic diagram of the utility model.

[0008] Figure 2 It is a schematic diagram of the PT parallel circuit of the utility model circuit breaker feeder cabinet.

[0009] In the figure, 1, intermediate relay, 1' normally open contact of intermediate relay, 1'', normally closed contact of intermediate relay, 2, voltage relay, 2' normally closed contact of voltage relay, 3, voltage relay, 3' normally closed contact of voltage relay, 4, voltage relay, 4' normally closed contact of voltage relay, 5, knob switch, 6, signal indicator light. Specific implementation method:

[0010] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0011] See also Figure 1 to Figure 2, an improved PT monitoring switching device in a flameproof high-voltage power distribution device for mining, including a busbar-specific PT, a circuit breaker-attached PT, and also including a 110V intermediate relay 1, a DY-36 / 160V voltage relay 2, a DY-36 / 160V voltage relay 3, a DY-36 / 160V voltage relay 4, a knob switch 5 and a 110V signal indicator 6; the coils of the voltage relay 2, the voltage relay 3 and the voltage relay 4 are respectively connected between the secondary side AB phase, BC phase and LN phase of the circuit breaker-attached PT; the voltage relay 2, the voltage relay 3 and the voltage relay 4 are respectively connected between the secondary side AB phase, the BC phase and the ... After the auxiliary normally open contacts 2' corresponding to the relay 3 and the voltage relay 4, the normally closed contacts 3' of the voltage relay, the normally closed contacts 4' of the voltage relay and the knob switch 5 are connected in parallel, they are connected in series with the coil of the intermediate relay 1 between the secondary side AB phases of the circuit breaker's built-in PT; an auxiliary normally open contact 1' of the intermediate relay 1 and a signal indicator light 6 are connected in series between the secondary side AB phases of the circuit breaker's built-in PT; the four auxiliary normally open contacts 1' of the intermediate relay 1 are connected in series to the busbar dedicated PT circuit; the four auxiliary normally closed contacts 1'' of the intermediate relay are connected in series to the circuit breaker's built-in PT circuit.

[0012] Turning the knob switch 5 can realize manual switching between the self-contained PT and the bus-specific PT. No matter if there is voltage abnormality at any point of the AB phase, BC phase, or LN phase on the secondary side of the self-contained PT, the intermediate relay 1 can be activated through the auxiliary normally open contact of the voltage relay, and then switched to the bus-specific PT circuit. The self-contained PT of the high-voltage circuit breaker feeder cabinet can be switched with the bus-specific PT cabinet, and the fault monitoring function of the self-contained PT can be realized, which improves the power supply reliability.

[0013] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. An improved PT monitoring switching device in a flameproof high-voltage power distribution device for mining, characterized in that: It includes an intermediate relay, three voltage relays, a knob switch and a signal indicator light. The coils of the three voltage relays are respectively connected between the AB phase, BC phase and LN phase of the secondary side of the PT of the circuit breaker. After the auxiliary normally open contacts of the three voltage relays and the knob switch are connected in parallel, they are connected in series with the coil of the intermediate relay between the AB phase of the secondary side of the PT of the circuit breaker. An auxiliary normally open contact of the intermediate relay and a signal indicator light are connected in series between the AB phase of the secondary side of the PT of the circuit breaker. The four auxiliary normally open contacts of the intermediate relay are connected in series to the busbar dedicated PT circuit. The four auxiliary normally closed contacts of the intermediate relay are connected in series to the PT circuit of the circuit breaker.

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