CN201188538Y

CN201188538Y - Alarm device for current deviation of juxtaposition operation transformers

Info

Publication number: CN201188538Y
Application number: CNU2008200209125U
Authority: CN
Inventors: 李�诚; 沈兴玉; 牛纪民
Original assignee: ZIBO HUALIAN MINING CO Ltd
Current assignee: Shandong Hualian Mining Co Ltd
Priority date: 2008-04-17
Filing date: 2008-04-17
Publication date: 2009-01-28
Anticipated expiration: 2018-04-17

Abstract

The utility model discloses a current deviation warning device of parallel-operation transformers, which comprises current mutual inductors, thermorelays and a warner. The current deviation warning device is characterized in that three current mutual inductors are respectively arranged on a three-phase interbus between two parallel-operation transformers; the outputs of the three current mutual inductors are respectively connected with three thermorelays and a current indicator in series; the normally open contacts of the three thermorelays are connected into a warner circuit after being connected in parallel; power is supplied for the warner through a fuse plug, and the output of the warner is connected with a warning electric bell or a warning signal long-transmitting circuit. The utility model solves the problem that because the overcurrent of a mine transformer can not be found in time, the transformer operating with overload can be damaged, and the utility model can be widely used for security protection for parallel-operation transformers of mining corporations.

Description

Paired running transformer current deviation alarm device

Technical field

The utility model relates to a kind of warning device, relates in particular to a kind of paired running transformer current deviation alarm device.

Background technology

Transformer is the important electric equipment in the power network, because the time of continuous operation is long, in order to make the transformer safety and economic operation and to improve the reliability and the flexibility of powering, is in operation usually with two or above parallel operation of transformers.Parallel operation of transformers, a winding with two or above transformer is connected in parallel on the bus of same voltage exactly, and secondary winding is connected in parallel on the bus of another voltage and moves.Its meaning is: when a transformer broke down, other transformer of paired running still can continue operation, to guarantee the electricity consumption of responsible consumer; Or the spare transformer of going up can be earlier when transformer need overhaul in parallel, the transformer interruption maintenance that will overhaul again can guarantee the scheduled overhaul of transformer can guarantee uninterrupted power supply again, improves the reliability of power supply.

The transformer of paired running, when need off-the-line transformer or inactive transformer, should be according to the actual load situation, estimate whether might cause the overload of a transformer, and should check the actual load electric current, might cause under the overladen situation of transformer, transformer is forbidden to carry out the off-the-line operation.

Present mining electric equipment is branch, the combined floodgate of two parallel operation of transformers of interconnection switch control, can not detect the deviation of its load current, if wherein one quit work, it is bigger than normal to load, can make another transformer cause damage, thereby influence safe power supply because of long-time overload operation.

The utility model content

The technical problems to be solved in the utility model is: the paired running transformer current deviation alarm device of in time reporting to the police when designing transformer running current, the overload operation of two paired runnings of a kind of real-time monitoring.

The technical solution of the utility model is: a kind of paired running transformer current deviation alarm device, comprise current transformer, thermal relay and alarm, it is characterized in that: three described current transformers are installed on respectively on two three-phase interbus between the paired running transformer, the output of three described current transformers is connected in series three thermal relays and electric current dial gauge respectively, insert described alarm loop after the normally opened contact parallel connection of three thermal relays, described alarm is exported electric bell taking alarm through the fuse single phase power supply.

Further, described alarm also comprises an alarm signal teletransmission circuit of being made up of auxiliary relay, and described auxiliary relay coils from parallel connection of coils is at warning electric bell two ends, its normally opened contact output alarm remote transfer signal.

The utility model compared with the prior art, have circuit simple, check easily, highly sensitive, advantage that expense is low, practical.

Description of drawings

Fig. 1 is the structure electrical schematic diagram of embodiment of the present utility model.

CTA, CTB, CTC among the figure: current transformer, FR: thermal relay, A1, A2, A3: electric current dial gauge, FU: fuse, DL: electric bell, KA: auxiliary relay.

Embodiment

The utility model is described in further detail below in conjunction with accompanying drawing.

In Fig. 1 electrical schematic diagram of the present utility model, three current transformer CTA, CTB, CTC is installed on respectively that two paired running transformer #1 become and the three-phase interbus of #2 between becoming on, one end of three described current transformers is connected to each other directly ground connection of back, other end output is connected in series three thermal relay FR and electric current dial gauge A1 respectively, A2, ground connection behind the A3, insert described alarm loop after the normally opened contact parallel connection of three thermal relays, alarm through fuse FU by three phase supply A, B, any phase among the C is C phase single phase power supply as shown in fig. 1, gets back to interbus N line behind the output serial connection warning electric bell DL.

In addition, also comprise an alarm signal teletransmission circuit of being made up of auxiliary relay KA, the coils from parallel connection of coils of auxiliary relay KA is at warning electric bell DL two ends, its normally opened contact output alarm remote transfer signal.

When interconnection switch is closed among the figure, two transformer #1 become and the flexible interbus parallel running excessively of #2, if wherein one quits work, then all load will be born by another transformer, by observing three current transformer CTA, CTB, CTC output current Table A 1, A2, the electric current indication of A3, just can detect the deviation of knowing load current, if this moment, load was bigger, load current has surpassed the setting operating current of transformer, because having designed the output of threephase current transformer is connected in series respectively by thermal relay FR, then when instrument transformer output current any moves set point greater than thermal relay, thermal relay FR action, its normally opened contact closure, the alarm loop is charged, and warning electric bell DL sends warning, realize warning function on the spot, auxiliary relay KA coil is charged simultaneously, and it inserts the normally opened contact closure of warning output loop, realizes the remote alarms function.

The utility model has solved mining transformer and can not in time find because of overcurrent, causes the problem of transformer overload operation damage, can be widely used in the safeguard protection of mining firm's parallel running transformer.

Claims

1, a kind of paired running transformer current deviation alarm device, comprise current transformer, thermal relay and alarm, it is characterized in that: three described current transformers are installed on respectively on two three-phase interbus between the paired running transformer, the output of three described current transformers is connected in series three thermal relays and electric current dial gauge respectively, insert described alarm loop after the normally opened contact parallel connection of three thermal relays, described alarm is exported electric bell taking alarm through the fuse single phase power supply.

2, paired running transformer current deviation alarm device according to claim 1, it is characterized in that: described alarm also comprises an alarm signal teletransmission circuit of being made up of auxiliary relay, described auxiliary relay coils from parallel connection of coils is at warning electric bell two ends, its normally opened contact output alarm remote transfer signal.