阅读说明：本技术 变压器差动保护信号转换电路 (Transformer differential protection signal conversion circuit ) 是由 臧维乔 方金土 张烨 张明月 陶滔 王熙 潘东辉 章振宇 马斌 吴品 于 2021-09-28 设计创作，主要内容包括：本公开属于核电技术领域,具体涉及一种变压器差动保护信号转换电路。本公开中,电容与第一继电器的线圈并联,形成并联子模块,并联子模块的一端接地,并联子模块的另一端通过第一反向二极管与第四端子连接；第一开关的输入端通过第二反向二极管与第一电源连接,第一开关的第一输出端连接在并联子模块与第一反向二极管之间,第一开关的第二输出端与第三端子连接；第二开关的输入端与第一端子连接,第二开关的第一输出端与第二端子连接,第二开关的第二输出端为开路；本公开的变压器差动保护信号转换电路在捕获差动脉冲信号后将其转换为常闭合触点信号并对外输出,从而使得火灾报警系统及时接收到差动保护信号。(The disclosure belongs to the technical field of nuclear power, and particularly relates to a transformer differential protection signal conversion circuit. In the disclosure, a capacitor is connected in parallel with a coil of a first relay to form a parallel sub-module, one end of the parallel sub-module is grounded, and the other end of the parallel sub-module is connected with a fourth terminal through a first reverse diode; the input end of the first switch is connected with the first power supply through a second backward diode, the first output end of the first switch is connected between the parallel sub-module and the first backward diode, and the second output end of the first switch is connected with a third terminal; the input end of the second switch is connected with the first terminal, the first output end of the second switch is connected with the second terminal, and the second output end of the second switch is open; the transformer differential protection signal conversion circuit converts differential pulse signals into normally closed contact signals after capturing the differential pulse signals and outputs the normally closed contact signals to enable a fire alarm system to receive the differential protection signals in time.)

1. A transformer differential protection signal conversion circuit, comprising: the circuit comprises a first power supply, a first relay, a capacitor, a first backward diode, a second backward diode and a first terminal row, wherein the first relay is used for controlling a first switch and a second switch to act, and the first terminal row comprises a first terminal, a second terminal, a third terminal and a fourth terminal;

the capacitor is connected with a coil of the first relay in parallel to form a parallel sub-module, one end of the parallel sub-module is grounded, and the other end of the parallel sub-module is connected with the fourth terminal through the first reverse diode;

the input end of the first switch is connected with the first power supply through the second backward diode, the first output end of the first switch is connected between the parallel submodule and the first backward diode, and the second output end of the first switch is connected with the third terminal;

an input end of the second switch is connected with the first terminal, a first output end of the second switch is connected with the second terminal, and a second output end of the second switch is open;

under the condition that the third terminal and the fourth terminal are not input with a transformer differential protection signal of a fire alarm system, the first relay is in a power-off state, the input end of the first switch is connected with the second output end of the first switch, and the input end of the second switch is connected with the second output end of the second switch;

under the condition that the third terminal and the fourth terminal input a transformer differential protection signal of a fire alarm system, the capacitor is charged and supplies power to the first relay, the first relay is powered on, so that the input end of the first switch is connected with the first output end of the first switch, the input end of the second switch is connected with the first output end of the second switch, the first terminal is communicated with the second terminal, and a normally-closed signal is output to the fire alarm system.

2. The transformer differential protection signal conversion circuit according to claim 1, wherein the capacitance of the capacitor is between 0.00001 and 0.00002 farad, and the discharge time of the capacitor is between 30 and 50 milliseconds.

3. The transformer differential protection signal conversion circuit of claim 1, further comprising a first indicator light connected in parallel with the first relay.

4. The transformer differential protection signal conversion circuit of claim 1, further comprising: a second relay, a third switch, a second terminal row comprising a fifth terminal and a sixth terminal;

a coil of the second relay is connected with the second power supply, and the second power supply is used for supplying power to the fire alarm system;

under the condition that the second power supply supplies power, the second relay is in a power-on state, and the second switch is closed, so that the fifth terminal and the sixth terminal are connected to output a normally-closed signal;

under the condition that the second power supply does not supply power, the second relay is in a power-off state, and the second switch is switched off, so that an open-circuit output normally-open signal is formed between the fifth terminal and the sixth terminal.

5. The transformer differential protection signal conversion circuit of claim 1, further comprising a second indicator light connected in parallel with the second relay.

6. The transformer differential protection signal conversion circuit of claim 1, further comprising: the power supply comprises a third power supply, a fourth power supply, a normally open switch, a chip, a variable resistor and a diode;

the third power supply is connected with the first input end of the chip through the normally open switch;

the fourth power supply is connected with the second input end of the chip through the variable resistor;

the output end of the chip is connected with the anode of the diode, and the cathode of the diode is connected to the coil of the first relay;

when the normally open switch is closed, the power supply inputs a trigger signal to the first input end, the output end of the chip outputs a pulse signal, the pulse signal is used for simulating a differential protection signal of the transformer, and the pulse width of the pulse signal is changed along with the resistance value of the variable resistor.

7. The transformer differential protection signal conversion circuit of claim 1, further comprising a first jumper connected between the diode and the first relay.

8. The transformer differential protection signal conversion circuit of claim 1, further comprising a second jumper connected between the second power source and the second relay.

Technical Field

The invention belongs to the technical field of nuclear power, and particularly relates to a transformer differential protection signal conversion circuit.

Background

The differential protection signal is a leakage protection signal of the transformer. When the differential protection signal is triggered, the transformer is powered off, so that the protection effect is achieved, and accidents such as electric leakage deterioration and fire disasters are prevented. The differential protection signal is a very short contact signal, the transformer power supply is immediately disconnected when the signal is triggered, and the differential protection signal disappears immediately, and the duration is generally about 50ms (millisecond).

The fire alarm system connects the detectors, modules and other devices in series through bus communication to form a loop, and the fire alarm controller completes communication in a mode of polling the devices in the loop one by one. In the design of industrial fields of nuclear power plants, thermal power plants and the like, a transformer differential protection signal is introduced into a fire alarm system, and when the transformer differential protection signal is triggered, the transformer differential protection signal can be used as early warning of fire alarm in a transformer area and can also participate in fire-fighting linkage control in the transformer area. However, in the related art, the loop inspection cycle of the fire alarm system is much longer than the millisecond level, and the differential protection signal cannot be captured by the fire alarm system module at a large probability when triggered, so how to effectively capture the differential protection signal by the fire alarm system becomes an urgent problem to be solved.

Disclosure of Invention

In order to overcome the problems in the related art, a transformer differential protection signal conversion circuit is provided.

According to an aspect of the embodiments of the present disclosure, there is provided a transformer differential protection signal conversion circuit, including: the circuit comprises a first power supply, a first relay, a capacitor, a first backward diode, a second backward diode and a first terminal row, wherein the first relay is used for controlling a first switch and a second switch to act, and the first terminal row comprises a first terminal, a second terminal, a third terminal and a fourth terminal;

the capacitor is connected with a coil of the first relay in parallel to form a parallel sub-module, one end of the parallel sub-module is grounded, and the other end of the parallel sub-module is connected with the fourth terminal through the first reverse diode;

the input end of the first switch is connected with the first power supply through the second backward diode, the first output end of the first switch is connected between the parallel submodule and the first backward diode, and the second output end of the first switch is connected with the third terminal;

an input end of the second switch is connected with the first terminal, a first output end of the second switch is connected with the second terminal, and a second output end of the second switch is open;

under the condition that the third terminal and the fourth terminal are not input with a transformer differential protection signal of a fire alarm system, the first relay is in a power-off state, the input end of the first switch is connected with the second output end of the first switch, and the input end of the second switch is connected with the second output end of the second switch;

under the condition that the third terminal and the fourth terminal input a transformer differential protection signal of a fire alarm system, the capacitor is charged and supplies power to the first relay, the first relay is powered on, so that the input end of the first switch is connected with the first output end of the first switch, the input end of the second switch is connected with the first output end of the second switch, the first terminal is communicated with the second terminal, and a normally-closed signal is output to the fire alarm system.

In one possible implementation, the capacitance of the capacitor is between 0.00001 and 0.00002 farad and the discharge time of the capacitor is between 30 and 50 milliseconds.

In a possible implementation manner, the transformer differential protection signal conversion circuit further includes a first indicator light, and the first indicator light is connected in parallel with the first relay.

In one possible implementation manner, the transformer differential protection signal conversion circuit further includes: a second relay, a third switch, a second terminal row comprising a fifth terminal and a sixth terminal;

a coil of the second relay is connected with a power supply of the fire alarm system;

under the condition that the second power supply supplies power, the second relay is in a power-on state, and the second switch is closed, so that the fifth terminal and the sixth terminal are connected to output a normally-closed signal;

under the condition that the second power supply does not supply power, the second relay is in a power-off state, and the second switch is switched off, so that an open-circuit output normally-open signal is formed between the fifth terminal and the sixth terminal.

In a possible implementation manner, the transformer differential protection signal conversion circuit further includes a second indicator light, and the second indicator light is connected in parallel with the second relay.

In one possible implementation manner, the transformer differential protection signal conversion circuit further includes: the power supply comprises a third power supply, a fourth power supply, a normally open switch, a chip, a variable resistor and a diode;

the third power supply is connected with the first input end of the chip through the normally open switch;

the fourth power supply is connected with the second input end of the chip through the variable resistor;

the output end of the chip is connected with the anode of the diode, and the cathode of the diode is connected to the coil of the first relay;

when the normally open switch is closed, the power supply inputs a trigger signal to the first input end, the output end of the chip outputs a pulse signal, the pulse signal is used for simulating a differential protection signal of the transformer, and the pulse width of the pulse signal is changed along with the resistance value of the variable resistor.

In one possible implementation manner, the transformer differential protection signal conversion circuit further includes a first jumper connected between the diode and the first relay.

In a possible implementation manner, the transformer differential protection signal conversion circuit further includes a second jumper connected between the second power supply and the second relay.

The beneficial effect of this disclosure lies in: according to the transformer differential protection signal conversion circuit, the circuit structures of the first power supply, the first relay, the capacitor, the first reverse diode, the second reverse diode and the first terminal bar are matched, so that the transformer differential protection signal conversion circuit can convert differential pulse signals into normally closed contact signals after capturing the differential pulse signals and output the normally closed contact signals outwards, and a fire alarm system can receive the differential protection signals in time; in addition, the capacitor is fully charged in the signal capturing process and supplies power to the first relay, so that the power-on time of the relay can be properly prolonged, the phenomenon that a gate is not in place in the power-on control process of the first relay is effectively prevented, and the success rate of signal capturing is ensured; furthermore, the output circuit of the normally closed signal is independent of the power supply circuit of the first relay, so that the situation that the differential signal does not disappear to form an internal circuit after the differential signal triggers the first switch to be closed is effectively avoided, and the stability of the circuit is improved.

Drawings

Fig. 1 is a schematic diagram illustrating a transformer differential protection signal conversion circuit according to an exemplary embodiment.

In the figure:

u1, a first power supply; u2, a second power supply; u3, third power supply; u4, a fourth power supply; relay2, first Relay; relay1, second Relay; c6, capacitance; d1, a first backward diode; d4, a second backward diode; d6, a diode; j2, first terminal row; j1, second terminal row; JP1, first jumper; JP2, second jumper; LED1, first indicator light; LED2, a second indicator light; U2A, chip; j2-2, a first terminal; j2-3, a second terminal; j2-4 third terminal; j2-5, a fourth terminal; j2-4, a third terminal; j2-5, a fourth terminal; s1, a reset switch; s2, normally open switch.

Detailed Description

The invention is described in further detail below with reference to the figures and the embodiments.

Fig. 1 is a schematic diagram illustrating a transformer differential protection signal conversion circuit according to an exemplary embodiment. As shown in fig. 1, the transformer differential protection signal conversion circuit includes: the Relay type power supply comprises a first power supply U1, a first Relay2, a capacitor C6, a first reverse diode D1, a second reverse diode D4 and a first terminal row J2, wherein the first Relay Relay2 is used for controlling the actions of a first switch (t1, t2, t3) and a second switch (t4, t5, t6), the first switch and the second switch can be single-pole double-throw switches, and the first terminal row J2 comprises a first terminal J2-2, a second terminal J2-3, a third terminal J2-4 and a fourth terminal J2-5;

the capacitor C6 is connected with a coil of the first Relay2 in parallel to form a parallel sub-module, one end of the parallel sub-module is grounded, and the other end of the parallel sub-module is connected with a fourth terminal J2-5 through a first reverse diode D1;

the input end t1 of the first switch is connected with a first power supply U1 through a second reverse diode D4, the first output end t2 of the first switch is connected between the parallel sub-module and the first reverse diode D1, and the second output end t3 of the first switch is connected with a third terminal J2-4;

the input end t4 of the second switch is connected with the first terminal J2-2, the first output end t5 of the second switch is connected with the second terminal J2-3, and the second output end J2-3 of the second switch is open;

the third terminal J2-4 and the fourth terminal J2-5 can be connected to a monitoring module of the fire alarm system, when the monitoring module of the fire alarm system does not input a transformer differential protection signal, the first Relay2 is in a power-off state, the input end t1 of the first switch is connected with the second output end t3 of the first switch through a barrier of the first switch, and the input end t4 of the second switch is connected with the second output end t6 of the second switch through a barrier of the second switch.

In case that the fire alarm system monitoring module inputs the transformer differential protection signal through the third terminal J2-4 and the fourth terminal J2-5, the capacitor C6 is charged, and supplies power to the first Relay2, the first Relay2 is electrified, so that the gates of the first switch and the second switch are actuated, the input end t1 of the first switch is connected with the first output end t2 of the first switch, and the input terminal t4 of the second switch is connected with the first output terminal t5 of the second switch, so that the first power source U1 is communicated with the first Relay2 to continuously supply power to the first Relay2, and the input terminal t4 of the second switch is continuously connected with the first output terminal t5 of the second switch, therefore, the first terminal and the second terminal are communicated, and the normally closed signal is continuously output to the fire alarm system, so that the fire alarm system can timely receive the differential protection signal.

In a possible implementation manner, the transformer differential protection signal conversion circuit further includes a reset switch S1, the reset switch S1 is a normally closed switch, and is connected between the input terminal t1 of the first switch and the first backward diode D4, and in a case where the input terminal t1 of the first switch is connected to the first output terminal t2 of the first switch, the transformer differential protection signal conversion circuit may be reset by turning off the reset switch S1.

According to the transformer differential protection signal conversion circuit, the circuit structures of the first power supply, the first relay, the capacitor, the first reverse diode, the second reverse diode and the first terminal bar are matched, so that the transformer differential protection signal conversion circuit can convert differential pulse signals into normally closed contact signals after capturing the differential pulse signals and output the normally closed contact signals outwards, and a fire alarm system can receive the differential protection signals in time; in addition, the capacitor is fully charged in the signal capturing process and supplies power to the first relay, so that the power-on time of the relay can be properly prolonged, the phenomenon that a gate is not in place in the power-on control process of the first relay is effectively prevented, and the success rate of signal capturing is ensured; furthermore, the output circuit of the normally closed signal is independent of the power supply circuit of the first relay, so that the situation that the differential signal does not disappear to form an internal circuit after the differential signal triggers the first switch to be closed is effectively avoided, and the stability of the circuit is improved.

In one possible implementation, the capacitance of the capacitor is between 0.00001 and 0.00002 farad and the discharge time of the capacitor is between 30 and 50 milliseconds. Because the shortest signal of the differential signal is 50ms, the capacitance of the capacitor is between 0.00001 and 0.00002, the full charge of the capacitor is ensured within 50ms, in addition, the discharge time of the capacitor is 30 to 50ms, and because the action time of the relay is about 20 ms, the relay can not work when the voltage is too low, and the tail sound of the discharge is invalid, the discharge time of the capacitor between 30 to 50ms fully ensures the power supply requirement of the relay for completing the action.

In a possible implementation manner, the transformer differential protection signal conversion circuit further includes a first indicator light LED1, the first indicator light LED1 is connected in parallel with the first Relay2, and the first indicator light can indicate whether the transformer differential protection signal is input or not.

In one possible implementation manner, the transformer differential protection signal conversion circuit further includes: a second Relay1, a third switch, a second terminal row J1, the second terminal row J1 including a fifth terminal J1-1 and a sixth terminal J1-5;

a coil of the second Relay Relay1 is connected with a second power supply U2, and the second power supply U2 is used for supplying power for a fire alarm system;

under the condition that the second power supply U2 supplies power, the second Relay Relay1 is in an electrified state, the second switch is closed, so that the fifth terminal and the sixth terminal are connected to output a normally closed signal, and the normally closed signal is used for indicating that the fire alarm system supplies power normally.

Under the condition that the second power supply U2 does not supply power, the second Relay Relay1 is in a power-off state, and the second switch is switched off, so that an open circuit is formed between the fifth terminal and the sixth terminal to output a normally open signal, and the normally open signal is used for indicating that the fire alarm system is powered off.

In a possible implementation manner, the transformer differential protection signal conversion circuit further includes a second indicator light LED2, the second indicator light LED2 is connected in parallel with the second Relay1, and the second indicator light can indicate whether the fire alarm system is powered off or not.

In one possible implementation manner, the transformer differential protection signal conversion circuit further includes: a third power supply U3, a fourth power supply U4, a normally open switch, a chip U2A, a variable resistor and a diode D6; the variable resistor can be a variable resistor module, the variable resistor module can comprise a plurality of resistors and a plurality of dial switches, each resistor is connected with one dial switch in series to form a resistor submodule, the plurality of resistor submodules are connected in parallel to form the variable resistor module, the total resistance value of the variable resistor module can be set by controlling the switch of each resistor submodule, and in addition, the variable resistor can also be a sliding variable resistor.

The third power supply U3 is connected with the first input end of the chip U2A through a normally open switch, and the fourth power supply U4 is connected with the second input end of the chip U2A through a variable resistor;

the output end of the chip U2A is connected with the anode of a diode, and the cathode of the diode is connected with a coil of a first Relay Relay 2;

when the normally open switch is closed, the power supply inputs a trigger signal to the first input end, the output end of the chip U2A outputs a pulse signal, the pulse signal is used for simulating a differential protection signal of the transformer, and the pulse width of the pulse signal is changed along with the resistance value of the variable resistor.

In one possible implementation, the transformer differential protection signal conversion circuit further includes a first jumper JP1, and the first jumper JP1 is connected between the diode and the first Relay 2. In one possible implementation, the transformer differential protection signal conversion circuit further includes a second jumper JP2, and the second jumper JP2 is connected between the second power source U2 and the second Relay 1. Therefore, the first jumper and the second jumper can be controlled to be connected or disconnected according to requirements, and functions of power failure alarm and/or transformer differential triggering and the like are selected.

Having described embodiments of the present disclosure, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The terms used herein were chosen in order to best explain the principles of the embodiments, the practical application, or technical improvements to the techniques in the marketplace, or to enable others of ordinary skill in the art to understand the embodiments disclosed herein.