Automatic oil supplementing device and method for nuclear power emergency diesel generator set

Abstract

The present application relates to a kind of nuclear power emergency diesel generator set automatic oil supplement device and oil supplement method, including automatic oil supplement of lubricating oil, lubricating oil temperature control and the like function, can effectively improve the automation level of emergency diesel generator set, improve the work efficiency of nuclear power station operation personnel.The present application also simultaneously solves the problem that sensor detection is prone to deviation under the condition of jolt and sway, uses the numerical value of sensor in different positions to calculate, adapts the oil quantity monitoring and oil supplement action requirement under different working conditions.

Description

Technical Field

[0001] This invention relates to the field of nuclear power plant fuel replenishment technology, and in particular to an automatic fuel replenishment device and method for nuclear power emergency diesel generator sets. Background Technology

[0002] Nuclear power plants use diesel generator sets as emergency power sources. These units are in a standby state year-round, automatically starting to supply power to critical equipment in the event of a loss of external power to the nuclear island, ensuring the normal operation of critical equipment. In addition, the units undergo regular testing to ensure they can be used normally in emergency situations.

[0003] Currently, the oil pan capacity of nuclear power emergency diesel generator sets is limited and cannot meet the requirement of continuous operation for 72 hours under rated conditions. Therefore, the use of online lubricating oil replenishment devices is necessary. During emergency operation, manual oil replenishment through the unit's built-in lubricating oil filling port is inconvenient and labor-intensive. If lubricating oil is insufficient during unit operation, on-site verification is required, which is also labor-intensive, increasing the unit's operation and maintenance costs at the nuclear power plant and hindering the improvement of the nuclear power plant's safe and economical operation level. Summary of the Invention

[0004] In response to the shortcomings of the existing production technology, the applicant provides a reasonably structured automatic oil replenishment device and method for nuclear power emergency diesel generator sets, which can realize the functions of automatic oil replenishment and oil temperature control of emergency diesel generator sets, and meet the requirement of continuous operation of the unit for 72 hours under rated operating conditions.

[0005] The technical solution adopted in this invention is as follows:

[0006] An automatic oil replenishment device for nuclear power emergency diesel generator sets is used to replenish oil in the oil sump. It includes an oil replenishment tank and a pipeline leading from the oil replenishment tank. A filter, an oil replenishment pump, and a solenoid valve are sequentially installed on the pipeline along the oil flow direction.

[0007] A temperature sensor is installed on the side wall of the lubricating oil replenishment tank, and a sensor array is installed inside the oil pan. The sensor array is used to determine the oil level inside the oil pan.

[0008] At least one coaxially arranged oil baffle is installed inside the oil pan, and the sensor group includes sensors disposed on the inner wall of the oil pan and sensors arranged in a ring array on the oil baffle.

[0009] As a further improvement to the above technical solution:

[0010] Heating cables are wrapped around the outer wall of the lubricating oil replenishment tank.

[0011] The sensors installed on the inner wall of the oil pan include an axially arranged high liquid level sensor and a low liquid level sensor.

[0012] The oil baffle is made of sheet-like or ring-shaped parts.

[0013] The area of ​​the hollow portion of the oil-blocking mesh is less than or equal to the area of ​​the solid portion.

[0014] The device is also equipped with a cable over-temperature protection sensor, which is used to actively cut off the heating circuit when the temperature is too high.

[0015] A method for replenishing fuel using an automatic fuel replenishment device for nuclear power emergency diesel generator sets includes the following steps:

[0016] The temperature sensor collects the low oil level switch signal in the oil pan and sets the replenishment pump to the active position.

[0017] Collect the high oil level switch signal from the oil pan and reset the electric lubricating oil replenishment pump's operating position.

[0018] When the temperature sensor detects a low lubricating oil temperature in the lubricating oil reservoir, it sets the heating cable to the active position; when it detects a high lubricating oil temperature in the reservoir, it resets the heating cable to the active position.

[0019] Once the replenishing pump is activated, the replenishing pump and solenoid valve are opened, and automatic replenishment begins; once the heating cable is activated, the heating cable begins to heat the lubricating oil in the tank.

[0020] When the electric lubricating oil replenishing pump is reset to zero, the replenishing pump and solenoid valve are shut off to stop replenishing oil; when the heating cable is detected to be reset to zero, the heating cable stops heating.

[0021] As a further improvement to the above technical solution:

[0022] The methods for determining the oil level in the oil pan are divided into two categories: bumpy operating conditions and stable operating conditions.

[0023] Under bumpy operating conditions, the controller calculates a theoretical approximation of the fluid level based on signals obtained from sensors on the side wall of the oil pan and from sensors on the oil baffle.

[0024] Under stable operating conditions, the signals emitted by the sensors on the side wall of the oil pan or the oil baffle can be used as control signals.

[0025] The beneficial effects of this invention are as follows:

[0026] Compared with existing technologies, the traditional nuclear power emergency diesel generator set has a limited oil pan capacity, which cannot meet the requirement of continuous operation of the nuclear power emergency unit for 72 hours under rated operating conditions. Therefore, it is necessary to put into use an online lubricating oil replenishment device.

[0027] During emergency operation of the unit, manual oil replenishment is performed through the unit's built-in lubrication port, which is labor-intensive. If the unit lacks lubrication during operation, it can only be confirmed and operated on-site, which is also labor-intensive, increasing the unit's operation and maintenance costs at the nuclear power plant site and hindering the improvement of the nuclear power plant's safe and economical operation level.

[0028] This invention proposes an online automatic lubricating oil replenishment device for nuclear power emergency diesel generator sets and its implementation method, which includes functions such as automatic lubricating oil replenishment and lubricating oil temperature control. It can effectively improve the automation level of emergency diesel generator sets and improve the work efficiency of nuclear power plant operation and maintenance personnel.

[0029] This invention also solves the problem that sensor detection is prone to deviation under bumpy and shaking conditions. It utilizes sensor values ​​from different locations to calculate and adapt to the requirements of oil quantity monitoring and oil replenishment under different working conditions. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the structure of the present invention.

[0031] Figure 2 This is a flowchart illustrating the workflow of the present invention.

[0032] The components include: 1. Lubricating oil replenishment tank; 2. Oil pan; 3. Heating cable; 4. Filter; 5. Breather valve; 6. Oil replenishment pump; 7. Solenoid valve; 8. Temperature sensor; 9. Oil baffle. Detailed Implementation

[0033] The specific embodiments of the present invention will now be described with reference to the accompanying drawings.

[0034] like Figure 1 As shown, the automatic oil replenishment device for nuclear power emergency diesel generator sets in this embodiment is used to replenish oil to the oil pan 2; it includes an oil replenishment tank 1 and a pipeline leading out from the oil replenishment tank 1. A filter 4, an oil replenishment pump 6, and a solenoid valve 7 are sequentially installed on the pipeline along the oil flow direction.

[0035] A temperature sensor 8 is installed on the side wall of the lubricating oil replenishment tank 1, and a sensor group is installed inside the oil pan 2. The sensor group is used to determine the oil level inside the oil pan 2.

[0036] At least one coaxially arranged oil baffle 9 is installed inside the oil pan 2. The sensor group includes sensors disposed on the inner wall of the oil pan 2 and sensors arranged in a ring array on the oil baffle 9.

[0037] The outer wall of the lubricating oil replenishment tank 1 is wrapped with heating cable 3.

[0038] The sensors installed on the inner wall of the oil pan 2 include an axially arranged high liquid level sensor and a low liquid level sensor.

[0039] The oil baffle 9 is made of sheet-like or ring-shaped parts.

[0040] The area of ​​the hollow part of the oil barrier 9 is less than or equal to the area of ​​the solid part.

[0041] The device is also equipped with a cable over-temperature protection sensor, which is used to actively cut off the heating circuit when the temperature is too high.

[0042] The fuel replenishment method using the automatic fuel replenishment device of the nuclear power emergency diesel generator set in this embodiment includes the following steps:

[0043] Temperature sensor 8 collects the low level switch signal of oil pan 2 and sets the oil replenishment pump 6 to the action position.

[0044] Collect the high level switch signal of oil pan 2 and reset the operation position of electric lubricating oil replenishment pump 6;

[0045] When temperature sensor 8 detects a low lubricating oil temperature signal in lubricating oil replenishment tank 1, it sets the heating cable 3 to the operating position; when it detects a high lubricating oil temperature signal in the replenishment tank, it resets the heating cable 3 to the operating position.

[0046] When the activation position of the oil replenishment pump 6 is detected, the oil replenishment pump 6 and the solenoid valve 7 are opened to start automatic oil replenishment; when the activation position of the heating cable 3 is detected, the heating cable 3 starts to heat the lubricating oil in the tank.

[0047] When the electric lubricating oil replenishing pump 6 is reset to zero, the replenishing pump 6 and solenoid valve 7 are turned off to stop replenishing oil; when the heating cable 3 is detected to be reset to zero, the heating cable 3 stops heating.

[0048] The methods for determining the oil level in oil pan 2 are divided into two categories: bumpy operating conditions and stable operating conditions.

[0049] Under bumpy operating conditions, the controller calculates a theoretical approximation of the fluid level based on signals obtained from sensors on the side wall of the oil pan 2 and from sensors on the oil baffle 9.

[0050] Under stable operating conditions, the signals emitted by the sensors on the side wall of the oil pan 2 or the sensors on the oil baffle 9 can be used as control signals.

[0051] The steps to determine the exact amount of oil in oil pan 2 are as follows:

[0052] Under severe vibration conditions, the median of the height of the oil baffle 9 (which receives intermittent signals) and the lowest height sensed by the side wall sensor is used to obtain a theoretical approximation of the actual oil level.

[0053] Under slight bumpy conditions, when all sensors on the oil baffle 9 detect the liquid level signal, they obtain the theoretical approximate value of the actual oil level. At this time, the actual oil level is higher than the height of the oil baffle 9.

[0054] By obtaining the high and low values ​​on the sidewall sensors at each time point, and taking the average or median, a theoretical approximation of the current lubricating oil level can be obtained.

[0055] Under normal and stable operating conditions, the signals emitted by the side wall sensor and the sensor on the oil baffle 9 can be used as control signals.

[0056] This implementation plan refers to Figure 1 and 2 The oil replenishment device includes a lubricating oil replenishment tank 1 for storing lubricating oil; the lubricating oil replenishment tank 1 is wrapped with a heating cable 3, which is used to automatically heat the lubricating oil in the tank.

[0057] The function of the oil replenishment device is to provide lubricating oil to the oil pan 2 of the emergency generator set in a timely manner. The oil pan 2 is equipped with a lubricating oil level sensor, which will promptly sound an alarm when it detects that the oil level in the oil pan 2 is low, and the alarm signal controls the start and stop of the oil replenishment operation.

[0058] A replenishment oil pipeline extends from the lubricating oil replenishment tank 1. Along the lubricating oil flow path on this pipeline are a filter 4, a replenishment oil pump 6, and a solenoid valve 7. One end of the replenishment oil pipeline is connected to the diesel engine filler port at the bottom of the oil pan 2. The replenishment oil pump 6 is electrically driven and is used for automatic replenishment of oil to the generator set.

[0059] A breather valve 5 is installed above the lubricating oil replenishment tank 1 to maintain the air pressure balance inside the tank. During the oil replenishment process, the breather valve 5 is connected to the atmosphere to maintain the air pressure balance between the inside and outside of the tank.

[0060] A temperature sensor 8 is installed on the side wall of the lubricating oil replenishment tank 1. The temperature sensor 8 can control the lubricating oil temperature.

[0061] In this embodiment, the oil inlet of the oil replenishment pump 6 is connected to the lubricating oil filter 4, and the oil outlet is connected to the oil inlet of the oil pan 2 of the nuclear power unit. The oil replenishment pump 6 draws lubricating oil from the oil replenishment tank and then automatically injects it into the oil pan 2 of the nuclear power unit to ensure the normal operation of the unit.

[0062] In this embodiment, the heating cable 3 uses multiple alloy heating wires as the heat source, which are wrapped around the outside of the oil tank to heat the lubricating oil inside the tank; the temperature sensor 8 collects the cable over-temperature sensor signal to prevent the temperature from getting too high and disconnect the power supply of the heating cable 3 in time.

[0063] The above structure is suitable for refueling operations under normal, stable environments. However, in actual operation, the working environment is not necessarily stable. If encountering a turbulent marine environment, the oil in the oil pan 2 and the refueling tank will slosh, causing sensor errors and affecting the determination of the refueling amount. One of the objectives of this invention is to mitigate the impact of unstable external environments on refueling operations and minimize errors in the refueling amount.

[0064] In this invention, an oil baffle 9 is added axially to the oil tank. The function of the oil baffle 9 is to block oil with a high flow rate when it splashes, but it is not very effective for oil with a slow flow rate. Therefore, this invention intervenes in two cases based on the intensity of the sloshing: violent splashing of oil in the tank and slow tilting of oil in the tank.

[0065] The oil baffle 9 can be circular or annular. At least on the circumference of the oil baffle 9, a circumferential array of sensors is set so that the plane on which the oil baffle 9 is located can sense the liquid level.

[0066] The ratio of the hole area to the solid plate area on the oil baffle 9 can be 1:1 or 1:2. The purpose is to effectively prevent some of the oil from splashing. If the hole area is too large, it will not be able to intercept the sloshing oil.

[0067] The annular oil baffle 9 is required to have a certain width to ensure that the lubricating oil can be caught by the oil baffle 9 during the shaking process.

[0068] In this embodiment, a sensor is also installed on the side wall of the oil pan 2 to obtain the liquid level at the side wall. The sensor on the side wall is also arranged in a circumferential manner to obtain the liquid level during sloshing.

[0069] The specific principle for measuring liquid level height, considering the different shaking conditions of the two, is as follows:

[0070] In the event of strong shaking, the oil baffle 9 can provide some protection, confining the oil as much as possible below the layer of oil baffle 9 above the oil level. When the sensor on the oil baffle 9 intermittently receives signals indicating contact with the oil, it can be determined that the lubricating oil level is lower than that layer of oil baffle 9. The approximate value of the actual oil level can be obtained by taking the median of the height of the oil baffle 9 and the lowest height sensed by the side wall sensor.

[0071] During the oil replenishment process, since the oil baffle 9 is set at a slightly higher height, when at least most of the sensors on the oil baffle 9 have detected the liquid level, it proves that a large area of ​​oil has been splashed onto the oil baffle 9 when it was splashed. At this time, the liquid level has approached the height of the oil baffle 9; it can be used in emergency situations under bumpy conditions.

[0072] For slow tilting situations, the sensors evenly distributed in a ring on the oil baffle 9 cannot all detect lubricating oil. Therefore, the system determines to calculate the oil level by averaging the values ​​from the sidewall sensors. By obtaining the high and low values ​​from the sidewall sensors at each time point, the average or median value can be taken to obtain the current lubricating oil level.

[0073] In the case of slight bumps, you can stop adding oil when all the sensors on the oil baffle 9 detect oil. At this time, the oil level is slightly higher than the height of the oil baffle 9, which is also a reasonable amount of oil.

[0074] In a normal and stable environment, the signals emitted by the side wall sensor and the sensor on the oil baffle 9 can be used as control signals.

[0075] The oil baffle 9 intervention structure provided by the present invention can be used in the oil pan 2 to accurately identify the remaining oil level in the oil pan 2, and can also be applied in the oil tank to identify the remaining oil level in the oil tank.

[0076] In this embodiment, the heating cable 3 wound around the outer wall of the lubricating oil replenishment tank 1 can be in one or more segments. Each segment of the heating cable 3 has several turns. If a single segment of the heating cable 3 is used, it is positioned near the bottom of the tank to ensure that it does not dry-burn due to low oil levels. If multiple segments are used, all segments can be heated simultaneously when there is a lot of oil; if the oil level gradually decreases, the heating cable 3 below the liquid level will be heated.

[0077] The operating status of the heating cables 3 is controlled by the temperature sensor 8 on the side wall of the lubricating oil replenishment tank 1. After the temperature sensor 8 obtains the lubricating oil level based on the built-in sensor, it determines which sets of heating cables 3 should be used for heating. The purpose of using multiple sets of heating cables 3 is to accelerate the heating rate and make the temperature rise of the oil in the tank more uniform throughout.

[0078] In this embodiment, the oil filling position at the oil pan 2 is set at the bottom of the oil pan 2, rather than being injected from top to bottom. This is to prevent the oil from splashing upwards when it falls. If it falls on the sensor, it can easily cause misreading of the sensor and affect the monitoring accuracy.

[0079] The oil replenishment method using the above-mentioned oil replenishment device includes the following steps:

[0080] Step 1:

[0081] Temperature sensor 8 collects the low level switch signal of oil pan 2 and sets the oil replenishment pump 6 to the action position.

[0082] Collect the high level switch signal of oil pan 2 and reset the operation position of electric lubricating oil replenishment pump 6;

[0083] When temperature sensor 8 detects a low lubricating oil temperature signal in lubricating oil replenishment tank 1, it sets the heating cable 3 to the operating position; when it detects a high lubricating oil temperature signal in the replenishment tank, it resets the heating cable 3 to the operating position.

[0084] Step 2:

[0085] When the activation position of the oil replenishment pump 6 is detected, the oil replenishment pump 6 and the solenoid valve 7 are opened to start automatic oil replenishment; when the activation position of the heating cable 3 is detected, the heating cable 3 starts to heat the lubricating oil in the tank.

[0086] Step 3:

[0087] When the electric lubricating oil replenishing pump 6 is reset to zero, the replenishing pump 6 and solenoid valve 7 are turned off to stop replenishing oil; when the heating cable 3 is detected to be reset to zero, the heating cable 3 stops heating.

[0088] The purpose of this invention is to provide an automatic oil replenishment method that, under the premise of being able to meet the requirements of automatic oil replenishment, can select the corresponding parameters of the sensor under conditions such as slight bumps, severe bumps, and slow tilting, and calculate the current liquid level height through the controller to determine the amount of remaining oil in the oil pan 2.

[0089] The device provided by this invention is not only suitable for diesel engine oil pan refueling, but theoretically, it can be applied to any container that needs refueling. Compared to conventional land-based refueling devices, the refueling device of this invention can also be used for container refueling on offshore platforms.

[0090] The above description is an explanation of the present invention and not a limitation thereof. The scope of the present invention is defined by the claims. Within the scope of protection of the present invention, any form of modification may be made.

Claims

1. An automatic fuel replenishment device for nuclear power emergency diesel generator sets, characterized in that: Used for replenishing oil to the oil pan (2); includes an oil replenishment tank (1) and a pipeline leading out from the oil replenishment tank (1), wherein a filter (4), an oil replenishment pump (6), and a solenoid valve (7) are sequentially arranged along the oil flow direction on the pipeline. A temperature sensor (8) is installed on the side wall of the lubricating oil replenishment tank (1), and a sensor group is installed inside the oil pan (2). The sensor group is used to determine the oil level inside the oil pan (2). At least one coaxially arranged oil baffle (9) is installed inside the oil pan (2). The sensor group includes a sensor installed on the inner wall of the oil pan (2) and a sensor arranged in a ring array on the oil baffle (9). The outer wall of the lubricating oil replenishment tank (1) is wrapped with a heating cable (3).

2. The automatic fuel replenishment device for nuclear power emergency diesel generator sets as described in claim 1, characterized in that: The sensors installed on the inner wall of the oil pan (2) include an axially arranged high liquid level sensor and a low liquid level sensor.

3. The automatic fuel replenishment device for nuclear power emergency diesel generator sets as described in claim 1, characterized in that: The oil baffle (9) is made of sheet-like or ring-shaped parts.

4. The automatic fuel replenishment device for nuclear power emergency diesel generator sets as described in claim 3, characterized in that: The area of ​​the hollow part of the oil-blocking mesh (9) is less than or equal to the area of ​​the solid part.

5. The automatic fuel replenishment device for nuclear power emergency diesel generator sets as described in claim 1, characterized in that: The device is also equipped with a cable over-temperature protection sensor, which is used to actively cut off the heating circuit when the temperature is too high.

6. A method for replenishing fuel using the automatic fuel replenishment device for nuclear power emergency diesel generator sets as described in claim 1, characterized in that, Includes the following steps: Temperature sensor (8) collects the low level switch signal of oil pan (2) and sets the oil replenishment pump (6) to the action position; Collect the high level switch signal of the oil pan (2) and reset the operation position of the electric lubricating oil replenishment pump (6); When the temperature sensor (8) collects a low lubricating oil temperature signal in the lubricating oil replenishment tank (1), it sets the heating cable (3) to the action position; when it collects a high lubricating oil temperature signal in the replenishment tank, it clears the heating cable (3) to the action position. When the activation position of the oil replenishment pump (6) is detected, the oil replenishment pump (6) and the solenoid valve (7) are opened to start automatic oil replenishment; when the activation position of the heating cable (3) is detected, the heating cable (3) starts to heat the lubricating oil in the tank; When the electric lubricating oil replenishing pump (6) is reset to zero, the replenishing pump (6) and solenoid valve (7) are turned off to stop replenishing oil; when the heating cable (3) is detected to be reset to zero, the heating cable (3) stops heating.

7. The oil replenishment method as described in claim 6, characterized in that, The methods for determining the oil quantity in the oil pan (2) are divided into two categories: bumpy operating conditions and stable operating conditions. Under bumpy conditions, the controller calculates a theoretical approximate value of the liquid level height based on the signals obtained from the sensors on the side wall of the oil pan (2) and the sensors on the oil baffle (9). Under stable operating conditions, the signals emitted by the sensors on the side wall of the oil pan (2) or the sensors on the oil baffle (9) can be used as control signals.

Images