阅读说明：本技术 一种矿井降温系统安全保护电路及控制方法 (Safety protection circuit of mine cooling system and control method ) 是由 胡家乐 华正 姚广兵 方亮 涂光 韩兴戚 张琪 李晨 于 2020-06-11 设计创作，主要内容包括：一种矿井降温系统安全保护电路及控制方法,涉及煤矿井下降温技术领域,解决如何避免制冷机内波纹铜管冻裂问题；电源正、负极通过微型断路器与线路综合保护装置连接；制冷机远控电路包括远控选择开关、远控合闸按钮、冷冻泵的停机继电器第一常开触点,远控选择开关、远控合闸按钮、线路综合保护装置、高压断路器依次串联后通过微型断路器与电源连接；远控选择开关、冷冻泵的停机继电器第一常开触点、线路综合保护装置、高压断路器依次串联后通过微型断路器与电源连接；制冷机近控电路、线路综合保护装置、高压断路器依次串联后通过微型断路器与电源连接；避免制冷机内波纹铜管冻裂的事故发生,优化制冷系统安全保护功能,提高制冷系统安全。(A safety protection circuit and a control method for a mine cooling system relate to the technical field of underground coal mine cooling and solve the problem of how to avoid the frost cracking of a corrugated copper pipe in a refrigerator; the positive pole and the negative pole of the power supply are connected with the comprehensive circuit protection device through a miniature circuit breaker; the remote control circuit of the refrigerator comprises a remote control selection switch, a remote control closing button and a first normally open contact of a shutdown relay of the refrigeration pump, wherein the remote control selection switch, the remote control closing button, the circuit comprehensive protection device and the high-voltage circuit breaker are sequentially connected in series and then connected with a power supply through a miniature circuit breaker; the remote control selection switch, a first normally open contact of a shutdown relay of the freezing pump, the comprehensive circuit protection device and the high-voltage circuit breaker are sequentially connected in series and then connected with a power supply through the miniature circuit breaker; the refrigerator near control circuit, the line comprehensive protection device and the high-voltage circuit breaker are sequentially connected in series and then connected with a power supply through a miniature circuit breaker; the freezing and cracking accidents of the corrugated copper pipe in the refrigerator are avoided, the safety protection function of the refrigerating system is optimized, and the safety of the refrigerating system is improved.)

1. A safety protection circuit of a mine cooling system is characterized by comprising a 220V power supply, a miniature circuit breaker (10), a line comprehensive protection device (1), a high-voltage circuit breaker (2), a refrigerator remote control circuit and a refrigerator near control circuit; the positive pole and the negative pole of the 220V power supply are connected with the comprehensive circuit protection device (1) through the miniature circuit breaker (10) and used for supplying power to the comprehensive circuit protection device (1); the refrigerator remote control circuit comprises a remote control selection switch (11), a remote control closing button (14) and a first normally open contact (16) of a shutdown relay of a freezing pump, wherein the remote control selection switch (11), the remote control closing button (14), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for starting the remote control refrigerator; the remote control selector switch (11), a first normally open contact (16) of a shutdown relay of the freezing pump, the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for shutdown of the remote control refrigerator; the refrigerator proximity control circuit, the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for starting and stopping the proximity control refrigerator.

2. The mine cooling system safety protection circuit according to claim 1, characterized by further comprising an alarm circuit, wherein the alarm circuit comprises a DC24V power supply, a shutdown relay second normally-open contact (31) of the freezing pump, an intermediate relay (32), an intermediate relay normally-open contact (33) and an alarm electric bell (34), the shutdown relay second normally-open contact (31) of the freezing pump is connected with the intermediate relay (32) in series and then connected to two ends of the DC24V power supply, the intermediate relay normally-open contact (33) is connected with the alarm electric bell (34) in series and then connected to two ends of the DC24V power supply, and the shutdown relay second normally-open contact (31) of the freezing pump is in the same switch state as the shutdown relay first normally-open contact (16) of the freezing pump.

3. The mine cooling system safety protection circuit according to claim 1, wherein the refrigerator proximity control circuit comprises a proximity control selection switch (12), a proximity control closing button (13) and a proximity control opening button (15); the near control selection switch (12), the near control closing button (13), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) and are used for near control starting of the refrigerator; the near-control selector switch (12), the near-control opening button (15), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for the near-control shutdown of the refrigerator.

4. The mine cooling system safety protection circuit according to claim 1, further comprising a quick-break over-temperature and over-voltage protection unit (17), wherein the quick-break over-temperature and over-voltage protection unit (17), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for quick-break, over-temperature and CT over-voltage protection of the circuit.

5. The mine cooling system safety protection circuit according to claim 1, characterized in that the high voltage circuit breaker (2) further comprises a locking unit (24), the positive pole and the negative pole of the 220V power supply are connected with the locking unit (24) through the miniature circuit breaker (10), and when a circuit fault is detected, the locking unit (24) is used for locking the high voltage circuit breaker (2) to prevent the high voltage circuit breaker (2) from being closed in a fault state to cause accidents.

6. The mine cooling system safety protection circuit according to claim 1, characterized in that the type of the line comprehensive protection device (1) is NSP 788.

7. The mine cooling system safety protection circuit according to claim 1, characterized in that the high voltage circuit breaker (2) is a 10kV high voltage vacuum circuit breaker, which is of type zw32-12/630 a.

8. The safety protection circuit of claim 1, wherein the refrigerating machines are two groups of electric refrigerating units, and the refrigerating capacity is not less than 2 x 6 MW.

9. The mine cooling system safety protection circuit of claim 1, wherein the refrigerator model is YKQ2QRK35 DHG.

10. A control method applied to the safety protection circuit of the mine cooling system as claimed in claims 1 to 9, characterized by comprising the following steps:

step one, remotely controlling and starting a refrigerator;

switching on the remote control selection switch 11, pressing the remote control closing button 14, electrifying a closing coil 21 of the high-voltage circuit breaker, closing the high-voltage circuit breaker, and operating the refrigerator, wherein the state switch 22 of the high-voltage circuit breaker is in a closed state;

step two, remotely controlling and stopping the refrigerator;

the remote control selection switch 11 is switched on, when the normally open contact of the freezing pump contactor is closed, the shutdown coil of the refrigerating machine is electrified, the shutdown normally open contact of the refrigerating machine is closed, the output shutdown relay coil is electrified, the first normally open contact 16 of the shutdown relay of the freezing pump is closed, the opening coil 23 of the high-voltage circuit breaker is electrified, the high-voltage circuit breaker is tripped, the refrigerating machine is shut down, and the state switch 22 of the high-voltage circuit breaker is in an open state;

step three: the refrigerator is turned on in a close control way;

closing the close control selection switch 12, pressing a close control closing button 13, electrifying a closing coil 21 of the high-voltage circuit breaker, closing the high-voltage circuit breaker, and operating the refrigerator, wherein the state switch 22 of the high-voltage circuit breaker is in a closed state;

step four: the refrigerator is shut down in a close control manner;

when the close control selection switch 12 is closed and the close control opening button 15 is pressed, the opening coil 23 of the high-voltage circuit breaker is electrified, the high-voltage circuit breaker is tripped, the refrigerator is stopped, and at the moment, the state switch 22 of the high-voltage circuit breaker is in an open state.

Technical Field

The invention belongs to the technical field of underground coal mine temperature reduction, and particularly relates to a safety protection circuit of a mine cooling system and a control method.

Background

The underground coal mine cooling system is provided with a group of heat and electric refrigerating units according to refrigerating capacity, a chilled water circulating pump is installed on the primary side of a ground refrigerating machine room, when the chilled water circulating pump stops running due to faults, a refrigerating unit cannot stop running and still continues to work, and the chilled water circulating pump cannot timely pump out chilled water in the refrigerating unit due to faults, so that the chilled water in the refrigerating unit can be frozen, and a corrugated copper pipe in the unit is frozen. The cost for replacing one corrugated copper pipe (the corrugated copper pipe and labor) is about 1000 yuan, the proportion of the frozen copper pipe caused by one fault is calculated according to 50%, and the economic loss is more than 45 ten thousand yuan; and when the coal mine is produced, once the refrigerating unit stops operating, the temperature of most underground working faces and the temperature of the tunneling head exceed the limit, so that the influence and loss caused by sunstroke of workers and face stop are extremely large.

Therefore, how to solve the problem that the refrigerating unit stops running when the refrigerating pump stops running is urgent, and meanwhile, an alarm is sent to remind an operator to check the fault reason in time and corresponding treatment is made.

Disclosure of Invention

The invention aims to solve the technical problem of how to realize that a refrigerating unit stops running and sends out an alarm signal when a freezing pump stops running, thereby avoiding the occurrence of the accident of frost cracking of a corrugated copper pipe in a refrigerating machine.

The invention solves the technical problems through the following technical scheme.

A safety protection circuit of a mine cooling system is characterized by comprising a 220V power supply, a miniature circuit breaker (10), a line comprehensive protection device (1), a high-voltage circuit breaker (2), a refrigerator remote control circuit and a refrigerator near control circuit; the positive pole and the negative pole of the 220V power supply are connected with the comprehensive circuit protection device (1) through the miniature circuit breaker (10) and used for supplying power to the comprehensive circuit protection device (1); the refrigerator remote control circuit comprises a remote control selection switch (11), a remote control closing button (14) and a first normally open contact (16) of a shutdown relay of a freezing pump, wherein the remote control selection switch (11), the remote control closing button (14), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for starting the remote control refrigerator; the remote control selector switch (11), a first normally open contact (16) of a shutdown relay of the freezing pump, the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for shutdown of the remote control refrigerator; the refrigerator proximity control circuit, the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for starting and stopping the proximity control refrigerator.

First normally open contact (16) of shut down relay through the cryopump and remote control option switch (11), circuit integrated protection device (1), high voltage circuit breaker (2) establish ties in proper order, in case the extrinsic cycle cryopump stop operation, the first normally open contact (16) of shut down relay of cryopump are closed, high voltage circuit breaker (2) separating brake, the refrigerator stops the operation immediately, the occurence of failure of corrugated copper pipe frost crack in the refrigerator has been avoided, refrigerating system's safety protection function has been optimized, very big improvement refrigerating system's safety.

As a further improvement of the technical scheme of the invention, the safety protection circuit of the mine cooling system further comprises an alarm circuit, the alarm circuit comprises a DC24V power supply, a second normally open contact (31) of a shutdown relay of the freezing pump, an intermediate relay (32), a normally open contact (33) of the intermediate relay and an alarm electric bell (34), the second normally open contact (31) of the shutdown relay of the freezing pump is connected with the intermediate relay (32) in series and then connected to two ends of the DC24V power supply, the normally open contact (33) of the intermediate relay is connected with the alarm electric bell (34) in series and then connected to two ends of the DC24V power supply, and the second normally open contact (31) of the shutdown relay of the freezing pump is in the same switch state as the first normally open contact (16) of the shutdown relay of the freezing pump.

As a further improvement of the technical scheme of the invention, the refrigerator near control circuit comprises a near control selection switch (12), a near control closing button (13) and a near control opening button (15); the near control selection switch (12), the near control closing button (13), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) and are used for near control starting of the refrigerator; the near-control selector switch (12), the near-control opening button (15), the line comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then connected with a 220V power supply through a miniature circuit breaker (10) for the near-control shutdown of the refrigerator.

As a further improvement of the technical scheme of the invention, the safety protection circuit of the mine cooling system further comprises a quick-break over-temperature and over-voltage protection unit (17), wherein the quick-break over-temperature and over-voltage protection unit (17), the circuit comprehensive protection device (1) and the high-voltage circuit breaker (2) are sequentially connected in series and then are connected with a 220V power supply through a miniature circuit breaker (10) for quick-break, over-temperature and CT over-voltage protection of the circuit.

As a further improvement of the technical scheme of the invention, the high-voltage circuit breaker (2) further comprises a locking unit (24), the positive pole and the negative pole of the 220V power supply are connected with the locking unit (24) through the miniature circuit breaker (10), and when a circuit fault is detected, the locking unit (24) is used for locking the high-voltage circuit breaker (2) to prevent the high-voltage circuit breaker (2) from being closed in a fault state to cause accidents.

As a further improvement of the technical scheme of the invention, the type of the line comprehensive protection device (1) is NSP 788.

As a further improvement of the technical scheme of the invention, the high-voltage circuit breaker (2) is a 10kV high-voltage vacuum circuit breaker, and the model is zw32-12/630 a.

As a further improvement of the technical scheme of the invention, the refrigerating machines are two groups of electric refrigerating units, and the refrigerating capacity is not lower than 2 multiplied by 6 MW.

As a further improvement of the technical scheme of the invention, the model of the refrigerator is YKQ2QRK35 DHG.

A control method applied to the safety protection circuit of the mine cooling system comprises the following steps:

step one, remotely controlling and starting a refrigerator;

switching on the remote control selection switch 11, pressing the remote control closing button 14, electrifying a closing coil 21 of the high-voltage circuit breaker, closing the high-voltage circuit breaker, and operating the refrigerator, wherein the state switch 22 of the high-voltage circuit breaker is in a closed state;

step two, remotely controlling and stopping the refrigerator;

the remote control selection switch 11 is switched on, when the normally open contact of the freezing pump contactor is closed, the shutdown coil of the refrigerating machine is electrified, the shutdown normally open contact of the refrigerating machine is closed, the output shutdown relay coil is electrified, the first normally open contact 16 of the shutdown relay of the freezing pump is closed, the opening coil 23 of the high-voltage circuit breaker is electrified, the high-voltage circuit breaker is tripped, the refrigerating machine is shut down, and the state switch 22 of the high-voltage circuit breaker is in an open state;

step three: the refrigerator is turned on in a close control way;

closing the close control selection switch 12, pressing a close control closing button 13, electrifying a closing coil 21 of the high-voltage circuit breaker, closing the high-voltage circuit breaker, and operating the refrigerator, wherein the state switch 22 of the high-voltage circuit breaker is in a closed state;

step four: the refrigerator is shut down in a close control manner;

when the close control selection switch 12 is closed and the close control opening button 15 is pressed, the opening coil 23 of the high-voltage circuit breaker is electrified, the high-voltage circuit breaker is tripped, the refrigerator is stopped, and at the moment, the state switch 22 of the high-voltage circuit breaker is in an open state.

The invention has the advantages that:

(1) first normally open contact (16) of shut down relay through the cryopump and remote control option switch (11), circuit integrated protection device (1), high voltage circuit breaker (2) establish ties in proper order, in case the extrinsic cycle cryopump stop operation, the first normally open contact (16) of shut down relay of cryopump are closed, high voltage circuit breaker (2) separating brake, the refrigerator stops the operation immediately, the occurence of failure of corrugated copper pipe frost crack in the refrigerator has been avoided, refrigerating system's safety protection function has been optimized, very big improvement refrigerating system's safety.

(2) An alarm circuit is designed, and when the external circulation refrigerating pump stops operating, the alarm circuit gives an alarm to prompt a worker to maintain in time.

(3) A quick-break overtemperature overvoltage protection unit is designed to protect quick break, overtemperature and CT overvoltage of a circuit.

(4) The locking unit is designed, and when a circuit fault is detected, the locking unit is used for locking the high-voltage circuit breaker to prevent the high-voltage circuit breaker from being closed in a fault state to cause an accident.

(5) The high-voltage circuit breaker is a 10kV high-voltage vacuum circuit breaker with the model of zw32-12/630a, the rated power frequency withstand voltage of the high-voltage vacuum circuit breaker can reach 42kV, the weight is light, and the mechanical life is long.

(6) The line comprehensive protection device is NSP788, and is high in test precision, strong in anti-interference capacity and reliable in protection action.

(7) The refrigerating capacity of the refrigerating machine is 1 multiplied by 6MW, the refrigerating capacity of the two groups of electric refrigerating units is 2 multiplied by 6MW, and 3 refrigerating units are connected in parallel for operation. The two groups of electric refrigerating unit units are manufactured by York corporation, the model is YKQ2QRK35DHG, the power of a refrigerating motor of the model is 1328KW, the voltage grade is 10KV, the refrigerating capacity is large, the operation is stable and reliable, and the electric refrigerating unit is suitable for mines.

Drawings

FIG. 1 is a schematic diagram of a refrigerator high-voltage cabinet control of a safety protection circuit of a mine cooling system according to an embodiment of the invention;

FIG. 2 is an alarm schematic diagram of a safety protection circuit of a mine cooling system according to an embodiment of the invention;

FIG. 3 is a diagram of the electrical main wiring of a refrigerator of the safety protection circuit of the mine cooling system according to the embodiment of the invention;

FIG. 4 is a diagram of the main electrical wiring of a refrigeration pump of the safety protection circuit of the mine cooling system according to the embodiment of the invention;

fig. 5 is a program diagram for stopping a refrigerator by PLC control of a safety protection circuit of a mine cooling system according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments of the present invention, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

The technical scheme of the invention is further described by combining the drawings and the specific embodiments in the specification: