An automatic isolation system for the normal fresh air pipeline in the main control room

Abstract

The present invention relates to an automatic isolation system for the normal fresh air pipeline in the main control room. By setting redundant shared normal fresh air pipelines and valves, when a valve on any normal fresh air pipeline fails, it automatically switches to another fresh air pipeline according to the status signal of the valve to ensure the supply of fresh air under normal operating conditions of the air conditioning system in the main control room. The electric isolation valves on any normal fresh air pipeline adopt the power supply method of the same column of power supply. The electric isolation valves on the normal fresh air pipeline adopt the power supply method that the motor power supply and the control power supply are from the same source. The control power supply is converted through the local control box, which can meet the simultaneous operation of the series-type electric isolation valves on any fresh air pipeline. By adopting the automatic isolation system for the normal fresh air pipeline in the main control room disclosed by the present invention, when an accident occurs outdoors, the automatic isolation function can be implemented in a timely and effective manner, ensuring the habitability of the main control room, optimizing the corrosion problem of the shared fresh air pipeline, improving the reliability of the system design, and enhancing the operating safety of the nuclear power plant.

Description

Technical Field

[0001] The invention belongs to the field of nuclear power safety, and particularly relates to an automatic isolation system for a normal fresh air pipeline in a main control room. Background Art

[0002] At present, the air conditioning systems in the main control room are all equipped with only one shared fresh air pipeline. Quick-closing electric isolation valves, regulating valves, check valves and other valves are serially arranged on the normal fresh air pipeline. The serially arranged electric isolation valves are required to meet the single failure criterion, so the normal power supply and the emergency power supplies A and B are respectively powered.

[0003] However, there is a time gap when switching between the normal power supply and the emergency diesel power supply or the SBO diesel power supply. Moreover, when the emergency diesel power supply is switched to the SBO diesel power supply, the power loads of columns A and B cannot be started simultaneously. And according to the principle of no intervention in the first 30 minutes under the SBO condition, the series-type electric isolation valves on the normal fresh air pipeline cannot be started simultaneously. That is, under the SBO condition (when there is no pollution outdoors), the normal fresh air pipeline is in a closed state, and according to the interlock control requirements, the exhaust fan is interlocked and stopped, and the main control room air conditioning system loses normal fresh air, which does not meet the design requirements and affects the habitability function of the main control room.

[0004] Moreover, serious corrosion on the normal fresh air pipeline or any valve failure will cause the normal fresh air pipeline to be unable to supply fresh air normally, affecting the habitability function of the main control room.

[0005] When a fire or toxic gas occurs outdoors, the normal fresh air inlets and exhaust outlets at the main control room pressure boundary cannot be quickly and effectively isolated in time. Summary of the Invention

[0006] Aiming at the defects existing in the prior art, the purpose of the invention is to provide an automatic isolation system for a normal fresh air pipeline in a main control room, which optimizes the corrosion problem of the shared fresh air pipeline concerned in the safety review and the poor habitability function of the main control room, improves the reliability of the system design, and improves the safety of nuclear power plant operation.

[0007] To achieve the above purpose, the technical solution adopted by the invention is: an automatic isolation system for a normal fresh air pipeline in a main control room, including at least two normal fresh air pipelines and a power control part. An electric isolation valve, a balance valve and a check valve are arranged on any one of the normal fresh air pipelines, and the balance valve and the check valve are both serially connected with the electric isolation valve on the same normal fresh air pipeline.

[0008] Further, at least two serially connected electric isolation valves are arranged on any one of the normal fresh air pipelines.

[0009] Further, the system further includes detectors disposed at the normal fresh air inlets, and the detectors include smoke detectors and toxic gas detectors.

[0010] Further, the detectors are interlocked with the electric isolation valves. When a fire or toxic gas release occurs outdoors, the detectors emit signals to interlock and close the electric isolation valves and exhaust fans on the normal fresh air pipelines.

[0011] Further, electric isolation valves are serially disposed on the exhaust air pipelines where the exhaust fans are located.

[0012] Further, at least two serially connected electric isolation valves disposed on any of the normal fresh air pipelines are powered by the same column of power supply, and the electric isolation valves on different normal fresh air pipelines are powered by different columns of power supply.

[0013] Further, the power supply includes a normal power supply, an emergency diesel engine power supply, and an SBO diesel engine power supply.

[0014] Further, the power control part includes a first power distribution panel, an electric control box, a second power distribution panel, and a DCS cabinet. Both the first power distribution panel and the second power distribution panel are 380V normal / emergency power distribution panels, the electric control box is a 220V electric control box, and the first power distribution panel and the second power distribution panel are of the same root and origin.

[0015] Further, the DCS cabinet controls the conversion of the 380V power in the first power distribution panel into 220V power in the electric control box.

[0016] Further, the electric isolation valves are quick-closing electric isolation valves.

[0017] The effects of the present invention are as follows: By adopting an automatic isolation system for the normal fresh air pipelines in the main control room disclosed by the present invention, by setting redundant valves on the fresh air pipelines, the technical problem that fresh air cannot be supplied to the inhabitable area in the main control room when any valve on the shared fresh air pipeline fails can be solved; by setting redundant fresh air pipelines, the technical problem that the shared fresh air pipelines are easily corroded and fresh air cannot be supplied to the inhabitable area in the main control room once the corrosion is serious can be solved; by setting detectors at the fresh air inlets, when a fire or toxic gas release occurs outdoors, the inhabitable boundary of the main control room can be automatically isolated in a timely and effective manner according to the detection signals fed back by the detectors, ensuring the habitability of the main control room. The electric isolation valves on any normal fresh air pipeline adopt the power supply method of the same column of power supply, and the electric isolation valves on the normal fresh air pipeline adopt the power supply method that the motor power supply and the control power supply are of the same root and origin, that is, both the motor power supply and the control power supply are powered by the same bus, and the control power supply is converted through the local control box, which can solve the problem that the series isolation valves powered by columns A and B on the shared fresh air pipeline cannot be opened simultaneously, ensuring the normal supply of fresh air. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 FIG. 1 is a schematic structural diagram of an automatic isolation system for a normal fresh air pipeline in a main control room according to Embodiment 1 of the present invention;

[0019] Figure 2 is Figure 1 FIG. 2 is a schematic diagram of a power control part of an automatic isolation system for a normal fresh air pipeline in a main control room shown in FIG. 1;

[0020] Wherein: 1 - electric isolation valve, 2 - electric isolation valve, 3 - balance valve, 4 - check valve, 5 - electric isolation valve, 6 - electric isolation valve, 7 - balance valve, 8 - check valve, 9 - detector, 10 - electric isolation valve, 11 - electric isolation valve, 12 - exhaust fan, 13 - first power distribution panel, 14 - DCS cabinet, 15 - second power distribution panel, 16 - electric control box. DETAILED DESCRIPTION OF THE INVENTION

[0021] The present invention will be further described below with reference to the drawings and specific embodiments.

[0022] Embodiment 1

[0023] As Figure 1 shown, this embodiment provides an automatic isolation system for a normal fresh air pipeline in a main control room, including at least two normal fresh air pipelines. At least two series-connected quick-closing type electric isolation valves are provided on any normal fresh air pipeline to meet mechanical redundancy. A balance valve and a check valve are provided on any normal fresh air pipeline, and the balance valve and the check valve are both connected in series with the quick-closing type electric isolation valve on the same normal fresh air pipeline.

[0024] In this embodiment, the normal fresh air pipeline is relative to the emergency fresh air pipeline.

[0025] In this embodiment, the automatic isolation system for the normal fresh air pipeline in the main control room includes two normal fresh air pipelines. Two quick-closing type electric isolation valves are connected in series on each of the two normal fresh air pipelines, and the quick-closing type electric isolation valves are 1, 2, 5, and 6 respectively.

[0026] The balance valve 3 and the check valve 4 are connected in series with the quick-closing type electric isolation valves 1 and 2, and the balance valve 7 and the check valve 8 are connected in series with the quick-closing type electric isolation valves 5 and 6.

[0027] The system further includes a detector 9 installed at the normal fresh air inlet. The detector includes a smoke detector and a toxic gas detector. When a fire or toxic gas release occurs outdoors, based on the detector 9 installed at the normal fresh air inlet, the electric isolation valves 1, 2, 5, and 6 on the normal fresh air pipeline are interlocked to close, and the exhaust fan 12 is interlocked to close according to the closing signal of the electric isolation valve, isolating the pressure boundary of the main control room to ensure the habitability function of the main control room. Electric isolation valves 10 and 11 are serially arranged on the exhaust air pipeline.

[0028] Among them, the electric isolation valves 1, 2, 5, and 6 are respectively powered by the power supplies of column A and column B. The power supplies of column A and column B include normal power supply, emergency diesel engine power supply, and SBO diesel engine power supply. As Figure 2 shown, the control part of the automatic isolation system for the normal fresh air pipeline of the main control room air conditioning system includes: the first power distribution panel 13, the electric control box 16, the second power distribution panel 15, and the DCS cabinet 14. Both the first power distribution panel 13 and the second power distribution panel 15 are 380V normal / emergency power distribution panels, and the electric control box 16 is a 220V electric control box. That is, the electric isolation valves 1, 2, 5, and 6 are mainly powered by the 220V isolation valve spring coil control power supply and the 380V isolation valve motor power supply. Among them, the first power distribution panel 13 and the second power distribution panel 15 belong to the same root and the same source of power, and the power supply columns of the series-type electric isolation valves are the same, ensuring the consistency of the power loading timing under any working condition, that is, ensuring that the series-type electric isolation valves on the same normal fresh air pipeline can be opened or closed simultaneously. Moreover, the 220V control power supply required by the isolation valve spring coil only needs to be converted by the DCS cabinet 14 from the 380V power supply in the first power distribution panel 13 in the electric control box 16, and the 380V power supply required by the isolation valve motor is provided by the 380V distribution panel of the same root and the same source, simplifying the power supply and control principle.

[0029] It can be seen from the above embodiments that for an automatic isolation system for the normal fresh air pipeline of the main control room disclosed in the present invention, due to the provision of redundant shared normal fresh air pipelines, when a valve (including an isolation valve, a regulating valve, or a check valve) on any normal fresh air pipeline fails, it automatically switches to another fresh air pipeline according to the status signal of the valve. When any fresh air pipeline is severely corroded, it can be switched to another fresh air pipeline to ensure the supply of fresh air under normal conditions for the main control room air conditioning system.

[0030] The electric isolation valves on any normal fresh air pipeline adopt the power supply method of the same column of power supply, and are configured with an emergency diesel engine power supply and an SBO diesel engine power supply. The electric isolation valves on the normal fresh air pipeline adopt the power supply method of the same root and the same source for the motor power supply and the control power supply, that is, both the motor power supply and the control power supply are powered by the same bus, and the control power supply is converted through the local control box, which can meet the simultaneous operation of the series-type electric isolation valves on any fresh air pipeline.

[0031] The system described in the present invention is not limited to the embodiments described in the specific embodiments. Those skilled in the art can obtain other embodiments based on the technical solutions of the present invention, which also belong to the scope of the technical innovation of the present invention.

Claims

1. An automatic isolation system for the normal fresh air pipeline in the main control room, Characterized in that: It includes at least two normal fresh air pipelines and a power control part. An electric isolation valve, a balance valve and a check valve are arranged on any one of the normal fresh air pipelines. The balance valve and the check valve are both connected in series with the electric isolation valve on the same normal fresh air pipeline; at least two series-connected electric isolation valves are arranged on any one of the normal fresh air pipelines; the system also includes a detector arranged at the normal fresh air inlet, and the detector is interlocked with the electric isolation valve. When it is detected that a fire or the release of toxic gas occurs outdoors, the detector emits a signal to interlock and close the electric isolation valve and the exhaust fan on the normal fresh air pipeline; at least two series-connected electric isolation valves arranged on any one of the normal fresh air pipelines are powered by the same column of power supply. The electric isolation valves on the normal fresh air pipelines adopt the power supply method that the motor power supply and the control power supply are from the same source, that is, both the motor power supply and the control power supply are powered by the same busbar, and the control power supply is converted through the local control box. The electric isolation valves on different normal fresh air pipelines are powered by different columns of power supply.

2. An automatic isolation system for the normal fresh air pipeline in the main control room according to claim 1, Characterized in that: The detector includes a smoke detector and a toxic gas detector.

3. An automatic isolation system for the normal fresh air pipeline in the main control room according to claim 2, Characterized in that: An electric isolation valve is connected in series on the exhaust air pipeline where the exhaust fan is located.

4. An automatic isolation system for the normal fresh air pipeline in the main control room according to claim 1, Characterized in that: The power supply includes a normal power supply, an emergency diesel engine power supply and an SBO diesel engine power supply.

5. An automatic isolation system for the normal fresh air pipeline in the main control room according to claim 1, Characterized in that: The power control part includes a first power distribution panel, an electric control box, a second power distribution panel and a DCS cabinet. The first power distribution panel and the second power distribution panel are both 380V normal / emergency power distribution panels. The electric control box is a 220V electric control box. The first power distribution panel and the second power distribution panel are from the same source.

6. An automatic isolation system for the normal fresh air pipeline in the main control room according to claim 5, Characterized in that: The DCS cabinet controls the conversion of the 380V power supply in the first power distribution panel into 220V power supply in the electric control box.

7. An automatic isolation system for the normal fresh air pipeline in the main control room according to claim 1, Characterized in that: The electric isolation valve is a quick-closing type electric isolation valve.

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