CN221597065U - Transformer outlet cabinet control device - Google Patents
Transformer outlet cabinet control device Download PDFInfo
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- CN221597065U CN221597065U CN202323575247.XU CN202323575247U CN221597065U CN 221597065 U CN221597065 U CN 221597065U CN 202323575247 U CN202323575247 U CN 202323575247U CN 221597065 U CN221597065 U CN 221597065U
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- 230000006698 induction Effects 0.000 claims description 4
- 238000012423 maintenance Methods 0.000 abstract description 8
- 238000012544 monitoring process Methods 0.000 description 9
- 238000000034 method Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000001514 detection method Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 239000003990 capacitor Substances 0.000 description 1
- 239000000306 component Substances 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 238000013461 design Methods 0.000 description 1
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Abstract
The utility model discloses a transformer outlet cabinet control device.A second normally open auxiliary contact and a coil of a transformer cabinet door interlocking relay are connected in series between a secondary side power supply anode and a secondary side power supply cathode; the normally closed contact of the transformer cabinet door interlocking relay and the coil of the closing locking relay are connected in series between the anode of the secondary side power supply and the cathode of the secondary side power supply; and the switching-on output end of the microcomputer protection module is connected with a normally open contact of a switching-on latching relay, the other end of the normally open contact of the switching-on latching relay is connected with one end of a switching-on coil, and the other end of the switching-on coil is connected with the negative electrode of a secondary side power supply. The utility model can improve the safety of the transformer during maintenance.
Description
Technical Field
The utility model relates to the field of transformer protection, in particular to a transformer outlet cabinet control device.
Background
It is a common practice to configure primary and secondary devices in an electrical power system, where the primary devices include transformers, bus bars, circuit breakers, lines, voltage and current transformers, and the like. The secondary equipment includes various protection and monitoring devices.
Because the transformer is a core component in each power system, various faults and abnormal operation states of the power systems can occur in the operation of the power systems, and the relay protection device can reflect the faults or abnormal operation states of the electric elements in the power systems and act on the circuit breaker to trip or send out signals. For example, protection and measurement of the transformer are achieved through secondary current loops of current transformers on both high and low voltage sides of the transformer.
Microcomputer protection is widely applied in China, and has become a main type of relay protection device. Since the electric quantity of different objects to be protected varies, and the protection scheme formulated according to the electric quantity varies, microcomputer protection is generally classified into line protection, transformer protection, motor protection, capacitor protection, generator protection, bus protection, and the like according to the object to be protected.
The diversity of protection device types makes protection device more pertinent, comprehensive to the protection of various equipment, but has also increased the degree of difficulty of operation maintenance, mainly because the design of circuit structure is too numerous complicated, the node process that needs to pass through in the operation process, lead to transformer outlet cabinet when the trouble takes place trip time relatively longer, although plays the effect of protection at last, because the response time of tripping operation is long can make each electrical component in the system bear some harm in this time, for example the harm that the temperature risees and produces etc. therefore, the protection of current transformer outlet cabinet still remains to be improved. In addition, the cabinet door switch state of the transformer is not generally interlocked with the secondary side circuit, and in the actual operation process, if the cabinet door of the transformer is in an open state and no power is cut off, corresponding potential safety hazards exist for operators approaching the transformer.
Disclosure of utility model
The utility model provides a transformer outlet cabinet control device which can improve the safety of a transformer during maintenance.
The transformer outlet cabinet control device comprises a primary circuit and a secondary circuit, wherein the primary circuit comprises a breaker, a current transformer and a primary side bus, the breaker comprises a main switch, a tripping coil for the breaker, a closing coil for the breaker, a first normally open auxiliary contact and a second normally open auxiliary contact, the main switch is connected in series with the primary side bus, and the current transformer is matched with the bus;
The secondary circuit comprises a secondary side power supply anode, a secondary side power supply cathode, a microcomputer protection module and a closing control switch, wherein a current induction input end of the microcomputer protection module is connected with a current transformer, a tripping output end of the microcomputer protection module is connected with one end of a first normally open auxiliary contact, the other end of the first normally open auxiliary contact is connected with one end of a tripping coil, the other end of the tripping coil is connected with the secondary side power supply cathode, and the closing control switch is connected with a closing input end of the microcomputer protection module; still include transformer cabinet door interlocking relay, closing close locking relay, wherein:
The second normally open auxiliary contact and a coil of the transformer cabinet door interlocking relay are connected in series between the anode of the secondary side power supply and the cathode of the secondary side power supply;
The normally closed contact of the transformer cabinet door interlocking relay and the coil of the closing locking relay are connected in series between the anode of the secondary side power supply and the cathode of the secondary side power supply;
and the switching-on output end of the microcomputer protection module is connected with a normally open contact of a switching-on latching relay, the other end of the normally open contact of the switching-on latching relay is connected with one end of a switching-on coil, and the other end of the switching-on coil is connected with the negative electrode of a secondary side power supply.
Further, the circuit breaker further comprises a third normally closed auxiliary contact connected in series with the coil of the closing latching relay.
Further, the circuit breaker further comprises a fourth normally closed auxiliary contact, and the fourth normally closed auxiliary contact is connected with the normally open contact of the closing latching relay in series.
Further, the secondary circuit further comprises a first temperature control normally open contact of the transformer and a first signal relay, one end of the first temperature control normally open contact of the transformer is connected with the positive electrode of the secondary side power supply, the other end of the first temperature control normally open contact of the transformer is connected with one end of the first signal relay, and the other end of the first signal relay is connected with the input end of the microcomputer protection module.
Further, the secondary circuit further comprises a transformer second temperature control normally open contact and a second signal relay, one end of the transformer second temperature control normally open contact is connected with the positive electrode of the secondary side power supply, the other end of the transformer second temperature control normally open contact is connected with one end of the second signal relay, and the other end of the second signal relay is connected with the negative electrode of the secondary side power supply.
When the circuit breaker is in a combined state, the second normally open auxiliary contact is closed, and the coil of the transformer cabinet door interlocking relay is electrified, so that the lock combined with the transformer cabinet door is in a closed state, and the transformer cabinet door cannot be opened at the moment. When the circuit breaker is in an open state, the second normally open auxiliary contact is opened, so that the coil of the transformer cabinet door interlocking relay is electrified, the lock combined with the transformer cabinet door is in an open state, the transformer cabinet door can be opened at the moment, and maintenance personnel can enter the transformer room to overhaul the transformer. Therefore, after the interlocking relay of the transformer cabinet door is connected to the secondary circuit, maintenance personnel can only enter the transformer room to operate after the breaker is disconnected, so that the safety of the maintenance personnel is improved.
Drawings
Fig. 1 is a schematic structural diagram of a primary circuit of a transformer outlet cabinet control device.
Fig. 2 is a schematic structural diagram of a secondary circuit of a transformer outlet cabinet control device.
Fig. 3 is a schematic diagram of the switching of the circuit breaker to tripping as required in the closed state.
Fig. 4 is a schematic diagram of switching to closing as required with the circuit breaker in the open state.
The reference symbols in the drawings: the transformer comprises a current transformer A, a primary side bus M, a main switch DL, a tripping coil Y2, a closing coil Y3, a first normally-open auxiliary contact D11, a second normally-open auxiliary contact D12, a third normally-closed auxiliary contact D13, a fourth normally-closed auxiliary contact D14, a fifth normally-closed auxiliary contact D15, a secondary side power positive pole +KM, a secondary side power negative pole-KM, a microcomputer protection module U, a current induction input end XT1, a tripping output end XT2, a closing input end XT3, a closing output end XT4, a closing control switch K1, a coil Y1 of a closing latching relay, a normally-open contact Y11 of the closing latching relay, a first temperature-control normally-open contact WJ1, a first signal relay XJ1, a second temperature-control normally-open contact WJ2, a second signal relay XJ2, a coil WDS of a transformer cabinet door interlocking relay and a transformer cabinet door interlocking normally-closed contact LK.
Detailed Description
As shown in fig. 1 and 2, the transformer outlet cabinet control device comprises a primary circuit and a secondary circuit, wherein the primary circuit comprises a breaker, a current transformer A and a primary bus M, the breaker comprises a main switch DL, a tripping coil Y2 for the breaker, a closing coil Y3 for the breaker, a first normally open auxiliary contact D11 and a second normally open auxiliary contact D12, the main switch DL is connected in series with the primary bus M, and the current transformer A is matched with the bus M.
The secondary circuit comprises a secondary side power supply positive electrode +KM, a secondary side power supply negative electrode-KM, a microcomputer protection module U and a closing control switch K1, wherein the microcomputer protection module U is of a PMF702A type, the microcomputer protection module U is respectively connected with the secondary side power supply positive electrode +KM and the secondary side power supply negative electrode-KM, a current induction input end XT1 of the microcomputer protection module U is connected with a current transformer A, a tripping output end XT2 of the microcomputer protection module U is connected with one end of a first normally open auxiliary contact D11, the other end of the first normally open auxiliary contact D11 is connected with one end of a tripping coil Y2, and the other end of the tripping coil Y2 is connected with the secondary side power supply negative electrode-KM.
The closing control switch K1 is connected with a closing input end XT3 of the microcomputer protection module U. When the closing control switch K1 is closed, a control signal for closing the main switch DL of the circuit breaker is sent out, and the microcomputer protection module U outputs a closing instruction according to the closing control signal.
The transformer outlet cabinet control device also comprises a transformer cabinet door interlocking relay and a closing locking relay, wherein the transformer cabinet door interlocking relay is provided with a coil WDS and a normally closed contact LK, and the closing locking relay is provided with a coil Y3 and a normally open contact Y11. The second normally open auxiliary contact D12 and a coil WDS of the transformer cabinet door interlocking relay are connected in series between the positive pole +KM of the secondary side power supply and the negative pole-KM of the secondary side power supply, and the normally closed contact LK of the transformer cabinet door interlocking relay and a coil Y1 of the closing locking relay are connected in series between the positive pole +KM of the secondary side power supply and the negative pole-KM of the secondary side power supply.
And a closing output end XT4 of the microcomputer protection module U is connected with a normally open contact Y11 of a closing latching relay, the other end of the normally open contact Y11 of the closing latching relay is connected with one end of a closing coil Y3, and the other end of the closing coil Y3 is connected with a secondary side power supply negative electrode-KM.
The circuit breaker also comprises a third normally closed auxiliary contact D13, and the third normally closed auxiliary contact D13 is connected with a coil Y1 of the closing latching relay in series. And the power supply or the power failure of the coil Y1 of the switching latching relay is correspondingly controlled through the third normally closed auxiliary contact D13.
The circuit breaker also comprises a fourth normally closed auxiliary contact D14, and the fourth normally closed auxiliary contact D14 is connected with a normally open contact Y11 of the closing latching relay in series. And corresponding control is formed on a loop where the switching coil Y3 is located through the fourth normally closed auxiliary contact D14.
The circuit breaker further comprises a fifth normally-closed auxiliary contact D15, one end of the fifth normally-closed auxiliary contact D15 is connected with a sixth output end XT6 of the microcomputer protection module U, the other end of the fifth normally-closed auxiliary contact D15 is connected with one end of a fourth normally-closed auxiliary contact D14, the sixth output end XT6 of the microcomputer protection module U, the fifth normally-closed auxiliary contact D15 and the fourth normally-closed auxiliary contact D14, and a normally-open contact Y11 and a closing coil Y3 of the closing latching relay form a second combined gate loop. The fourth output end XT4 is used as a common output end for switching on, and the sixth output end XT6 is used as a standby output end for switching on.
The switching-on output end XT4 of the microcomputer protection module U, the fourth normally closed auxiliary contact D14, the normally open contact Y11 of the switching-on latching relay and the switching-on coil Y3 form a first combined switch loop.
The microcomputer protection device further comprises a tripping control switch K2, one end of the tripping control switch K2 is connected with the positive pole +KM of the secondary side power supply, and the other end of the tripping control switch K2 is connected with the closing input end XT7 of the microcomputer protection module U. The tripping control switch K2 and the closing control switch K1 are button switches.
The secondary circuit further comprises a first temperature control normally open contact WJ1 of the transformer and a first signal relay XJ1, one end of the first temperature control normally open contact WJ1 of the transformer is connected with the positive pole +KM of the secondary side power supply, the other end of the first temperature control normally open contact WJ1 of the transformer is connected with one end of the first signal relay XJ1, and the other end of the first signal relay XJ1 is connected with the input end XT5 of the microcomputer protection module U.
The temperature sensor (not shown in the figure) is arranged in the transformer, the temperature sensor detects the temperature of the transformer, the temperature sensor transmits detected temperature signals to the temperature monitoring module (not shown in the figure), the temperature monitoring module judges whether the detected temperature signals exceed a set threshold value according to actual measurement temperature signals provided by the temperature sensor, in the embodiment, at least a first temperature threshold value and a second temperature threshold value are arranged in the temperature monitoring module, when the detected temperature exceeds the first temperature threshold value, the temperature monitoring module controls the first temperature control normally open contact WJ1 to be closed, so that the first signal relay XJ1 is powered on, the microcomputer protection module U records the overtemperature condition, and the microcomputer protection module U of the PMF702A type is provided with a display screen and a query button and can query corresponding records so as to enable equipment maintenance personnel to perform corresponding maintenance according to conditions.
The secondary circuit further comprises a transformer second temperature control normally open contact WJ2 and a second signal relay XJ2, one end of the transformer second temperature control normally open contact WJ2 is connected with the positive pole +KM of the secondary side power supply, the other end of the transformer second temperature control normally open contact WJ2 is connected with one end of the second signal relay XJ2, and the other end of the second signal relay XJ2 is connected with the negative pole-KM of the secondary side power supply.
When the detected temperature exceeds a second temperature threshold, the temperature monitoring module controls the second temperature control normally open contact WJ2 to be closed, so that the second signal relay XJ2 is electrified, and the microcomputer protection module U records the over-temperature condition.
The working process of the utility model is as follows:
As shown in fig. 3, after the circuit breaker is closed, the circuit breaker is powered on, the main switch DL is closed, the transformer connected with the primary bus M can be powered on, the third normally closed auxiliary contact D13 of the circuit breaker is opened, the fourth normally closed auxiliary contact D14 is opened, the fifth normally closed auxiliary contact D15 is opened, and the second normally open auxiliary contact D12 is closed, the coil WDS of the transformer cabinet door interlock relay is powered on, the normally closed contact LK of the transformer cabinet door interlock relay is opened, the coil Y1 of the closing latching relay is in a power-off state, the normally open contact Y11 of the closing latching relay is opened, the loop where the closing coil Y3 is located is in an open state, in addition, when the circuit breaker is powered on, the first normally open auxiliary contact D11 is closed, and the loop where the trip coil Y2 is located is in a closed state, but since the trip output end XT2 of the microcomputer protection module U does not output a control voltage at this time, the trip coil Y2 is in a power-off state.
The current transformer a provides the sampled current signal to the microcomputer protection module U, and the microcomputer protection module U determines whether the current on the primary side bus M exceeds a set threshold, for example, the set threshold is 50A, if the current exceeds the set threshold, it is determined that the primary side has an overcurrent condition, at this time, the microcomputer protection module U controls the circuit breaker to be opened, the microcomputer protection module U outputs a voltage signal through the trip output terminal XT2, the voltage of the voltage signal adopts 220V, and the trip coil Y2 is powered on because the loop where the trip coil Y2 is located is in a closed state, thereby enabling the main switch DL of the circuit breaker to be in an open state.
Similarly, if the temperature detection signal of the transformer received by the temperature monitoring module exceeds the first temperature threshold, for example, 90 ℃, the temperature monitoring module controls the first temperature control normally open contact WJ1 to be closed, then the microcomputer protection module U outputs a voltage signal through the trip output terminal XT2, the voltage of the voltage signal is 220V, and the trip coil Y2 is powered on because the loop where the trip coil Y2 is located is in a closed state, so that the main switch DL of the circuit breaker is in an open state.
In addition, if the transformer temperature detection signal received by the temperature monitoring module exceeds the second temperature threshold value, for example, the second temperature threshold value is greater than 70 ℃ and less than 90 ℃, the temperature monitoring module controls the second temperature control normally open contact WJ2 to be closed (at this time, the first temperature control normally open contact WJ1 is in an open state), the second signal relay XJ2 is powered on, and an alarm circuit (not shown in the figure) connected with the normally open contact of the second signal relay XJ2 is connected, for example, to output an alarm signal.
In the tripping process, instead of the self-protection tripping, for example, the tripping control switch K2 may be closed to output a voltage signal from the microcomputer protection module U through the tripping output terminal XT2, and the tripping coil Y2 is powered on because the circuit in which the tripping coil Y2 is located is in a closed state, so that the main switch DL of the circuit breaker is in an open state. I.e. the trip is a manual trip mode of operation.
As shown in fig. 4, after the main switch DL is opened, the whole breaker is powered off, the first normally-open auxiliary contact D11 is opened, the trip coil Y2 is in a powered off state, the third normally-closed auxiliary contact D13 is closed, the fourth normally-closed auxiliary contact D14 is closed, the fifth normally-closed auxiliary contact D15 is closed, and the second normally-open auxiliary contact D12 is opened, the coil WDS of the transformer cabinet door interlocking relay is powered off, the transformer cabinet door interlocking relay normally-closed contact LK is closed, so that the coil Y1 of the closing latching relay is powered on, the normally-open contact Y11 of the closing latching relay is closed, and at this time, the loop where the closing coil Y3 is located is in a closed state. After the fault on the primary side is eliminated, the equipment maintainer selects the first set of contacts or the second set of contacts to switch on the switch-on control switch K1, for example, selects the first set of contacts, and the switch-on output end XT4 of the microcomputer protection module U outputs a voltage signal, for example, 220V voltage, so that current flows through a loop where the switch-on coil Y3 is located, the switch-on coil Y3 is electrified, and the main switch DL is switched on.
Claims (5)
1. The transformer outlet cabinet control device comprises a primary circuit and a secondary circuit, wherein the primary circuit comprises a circuit breaker, a current transformer (A) and a primary side bus (M), the circuit breaker comprises a main switch (DL), a tripping coil (Y2) for the circuit breaker, a closing coil (Y3) for the circuit breaker, a first normally open auxiliary contact (D11) and a second normally open auxiliary contact (D12), the main switch (DL) is connected in series with the primary side bus (M), and the current transformer (A) is matched with the bus (M);
The secondary circuit comprises a secondary side power supply anode (+KM), a secondary side power supply cathode (-KM), a microcomputer protection module (U) and a closing control switch (K1), wherein a current induction input end (XT 1) of the microcomputer protection module (U) is connected with a current transformer (A), a tripping output end (XT 2) of the microcomputer protection module (U) is connected with one end of a first normally open auxiliary contact (D11), the other end of the first normally open auxiliary contact (D11) is connected with one end of a tripping coil (Y2), the other end of the tripping coil (Y2) is connected with the secondary side power supply cathode (-KM), and the closing control switch (K1) is connected with a closing input end (XT 3) of the microcomputer protection module (U); the transformer cabinet door locking relay is characterized by further comprising a transformer cabinet door locking relay and a closing locking relay, wherein:
The second normally open auxiliary contact (D12) and a coil (WDS) of the transformer cabinet door interlocking relay are connected in series between the positive pole (+KM) of the secondary side power supply and the negative pole (-KM) of the secondary side power supply;
The normally closed contact (LK) of the transformer cabinet door interlocking relay and the coil (Y1) of the closing locking relay are connected in series between the positive pole (+KM) of the secondary side power supply and the negative pole (-KM) of the secondary side power supply;
the switching-on output end (XT 4) of the microcomputer protection module (U) is connected with a normally open contact (Y11) of a switching-on locking relay, the other end of the normally open contact (Y11) of the switching-on locking relay is connected with one end of a switching-on coil (Y3), and the other end of the switching-on coil (Y3) is connected with a negative electrode (-KM) of a secondary side power supply.
2. A transformer outlet cabinet control device according to claim 1, characterized in that the circuit breaker further comprises a third normally closed auxiliary contact (D13), the third normally closed auxiliary contact (D13) being connected in series with the coil (Y1) of the closing latching relay.
3. The transformer outlet cabinet control device according to claim 1, characterized in that the circuit breaker further comprises a fourth normally closed auxiliary contact (D14), the fourth normally closed auxiliary contact (D14) being connected in series with the closing latching relay normally open contact (Y11).
4. The transformer outlet cabinet control device according to claim 1, wherein the secondary circuit further comprises a transformer first temperature control normally open contact (WJ 1) and a first signal relay (XJ 1), one end of the transformer first temperature control normally open contact (WJ 1) is connected with the positive pole (+km) of the secondary side power supply, the other end of the transformer first temperature control normally open contact (WJ 1) is connected with one end of the first signal relay (XJ 1), and the other end of the first signal relay (XJ 1) is connected with the input end (XT 5) of the microcomputer protection module (U).
5. The transformer outlet cabinet control device according to claim 1, wherein the secondary circuit further comprises a transformer second temperature-control normally open contact (WJ 2) and a second signal relay (XJ 2), one end of the transformer second temperature-control normally open contact (WJ 2) is connected with the positive pole (+km) of the secondary side power supply, the other end of the transformer second temperature-control normally open contact (WJ 2) is connected with one end of the second signal relay (XJ 2), and the other end of the second signal relay (XJ 2) is connected with the negative pole (-KM) of the secondary side power supply.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202323575247.XU CN221597065U (en) | 2023-12-26 | 2023-12-26 | Transformer outlet cabinet control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202323575247.XU CN221597065U (en) | 2023-12-26 | 2023-12-26 | Transformer outlet cabinet control device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN221597065U true CN221597065U (en) | 2024-08-23 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202323575247.XU Active CN221597065U (en) | 2023-12-26 | 2023-12-26 | Transformer outlet cabinet control device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN221597065U (en) |
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2023
- 2023-12-26 CN CN202323575247.XU patent/CN221597065U/en active Active
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