Hot oil simulation system suitable for converter transformer fire extinguishing test and hot oil heating method

Abstract

The invention discloses a hot oil simulation system suitable for a converter transformer fire extinguishing test and a hot oil heating method, the hot oil simulation system comprises a heating unit, a heat preservation oil storage tank, a main oil tank top oil pool, a right side accident oil pool, a left side accident oil pool and an oil conservator, the heating unit is connected with the heat preservation oil storage tank and can heat the heat preservation oil storage tank; the oil conservator is communicated with the top oil pool of the main oil tank, the heat preservation oil storage tank is communicated with the top oil pool of the main oil tank through a first input pipeline and a first output pipeline, and the heat preservation oil storage tank is connected with the right side accident oil pool and the left side accident oil pool through a second input pipeline. And the right side accident oil pool and the left side accident oil pool are communicated with the heat preservation oil storage tank through a second output pipeline. Compared with the mode of directly heating the oil pool at the top of the main oil tank and the accident oil pools on the two sides by adopting electrical bars after oil injection, the oil temperature control mode that the heating unit firstly heats, then injects oil and then finely adjusts the oil temperature has the advantages of being high in safety, more uniform in oil temperature distribution and the like.

Description

Technical Field

[0001] The invention relates to the technical field of hot oil simulation, and more particularly to a hot oil simulation system and a hot oil heating method suitable for a converter variable fire extinguishing test. Background Art

[0002] UHV converter station is the hub of UHV DC transmission system, and UHV converter transformer is one of the core equipment of UHV converter station. Its safe and stable operation is the basis for the normal operation of UHV DC transmission system. The oil tank of ±800kV UHV converter transformer currently in use is more than 10m long and stores 130t or even more transformer oil. Its scale and oil storage capacity far exceed the conventional oil-immersed transformers targeted by existing fire protection standards. In addition, UHV converter transformers have high operating temperature and high heat. Once a fire occurs, it is easy to form a high-temperature hot oil fire, which is very difficult to extinguish. Existing accident cases have shown that the pipeline and nozzle layout of conventional water spray or foam spray fire extinguishing systems are easily damaged by transformer fire explosions, thereby reducing or losing their fire extinguishing capabilities. Therefore, in the fire protection improvement work of UHV converter stations, it is proposed to use a compressed air foam system with higher fire extinguishing efficiency and better explosion resistance as the main fire extinguishing improvement measure for UHV converter transformers.

[0003] Transformer oil is the main combustible material in converter transformers. According to research, each converter transformer stores 100 to 200 tons of oil. Transformer oil is generally mineral oil, a product of petroleum distillation. Its main components are compounds such as alkanes, cycloalkanes, saturated aromatic hydrocarbons, and unsaturated aromatic hydrocarbons. It is commonly known as square shed oil and is generally a light yellow transparent liquid. According to the national standard "Petrochemical Enterprise Design Fire Protection Code", this product belongs to Class C B combustible liquid.

[0004] Transformer oil is a flammable liquid with good insulation and thermal conductivity, but it has a high flash point (generally greater than 130°C). The flash point (closed cup) of KI50X transformer oil used in UHV converter station transformers is about 138°C and the ignition point is about 153°C. Therefore, under normal conditions, transformer oil cannot be directly ignited by a small ignition source.

[0005] Article 6.4 of the State Grid Standard "General Technical Conditions for Fixed Compressed Air Foam Fire Extinguishing Systems in UHV Converter Stations" (Q / GDW 12033-2020) stipulates the test requirements and methods for fixed compressed air foam fire extinguishing systems and components in UHV converter stations. Q / GDW 12033-2020 stipulates that before the test, 10.2 tons of test fuel must be added to the main oil tank. The test fuel is about 270 mm thick. The oil overflows from both sides. 2.6 tons of test fuel is added to each of the accident oil pools on both sides. The test fuel is about 100 mm thick. 5.0 tons of test fuel is added to the oil pillow. The transformer oil in the main oil tank and the accident oil pools on both sides is heated to 155°C or above, and the oil temperature of the oil pillow is heated to 90°C±5°C, but the specific heating method of the transformer oil is not specified.

[0006] In the past hot oil tests, due to the small scale of the tests, the oil pan was generally heated directly by heating the oil pool with built-in electric heating rods or directly heating the oil pool with gas. These heating methods have considerable limitations for the oil pool scale in Q / GDW 12033-2020. First, because the oil pool is large in area and the amount of oil is large, direct use of electric heating or gas heating requires a lot of power and due to the large heat dissipation surface, it is difficult to achieve the target oil temperature in a short time. Second, high-temperature heating of a large open oil pool is prone to the diffusion of oil vapor in the air, which may cause ignition and explosion, posing a safety risk. Summary of the invention

[0007] The technical problem to be solved by the present invention is how to achieve safe and reliable hot oil state simulation in a converter transformer fire extinguishing test with uniform oil temperature distribution.

[0008] The present invention solves the above technical problems through the following technical means: a hot oil simulation system suitable for a converter transformer fire extinguishing test, comprising a heating unit, an insulated oil storage tank, an oil pool on the top of a main oil tank, a right-side accident oil pool, a left-side accident oil pool, and an oil pillow, wherein the heating unit is connected to the insulated oil storage tank and can heat it; the oil pillow is connected to the oil pool on the top of the main oil tank, the insulated oil storage tank is connected to the oil pool on the top of the main oil tank through a first input pipeline and a first output pipeline, the insulated oil storage tank is connected to the right-side accident oil pool and the left-side accident oil pool through a second input pipeline, and the right-side accident oil pool and the left-side accident oil pool are connected. The side accident oil pool is connected with the insulated oil storage tank through the second output pipeline. The insulated oil storage tank, the main oil tank top oil pool, the right accident oil pool and the left accident oil pool are all equipped with temperature sensors. The heating unit heats the hot oil and injects it into the main oil tank top oil pool, the right accident oil pool and the left accident oil pool. The main oil tank top oil pool, the right accident oil pool and the left accident oil pool are used to detect whether the hot oil temperature therein reaches the set value. If the set value is not reached, the hot oil is circulated to the insulated oil storage tank for heating until the temperature in the main oil tank top oil pool, the right accident oil pool and the left accident oil pool reaches the set value and stops.

[0009] As a preferred technical solution, the heating unit includes a gas-fired hot oil generator, which is connected to the insulated oil storage tank via hot oil pipe one and hot oil pipe two.

[0010] As a preferred technical solution, the heating unit further includes a gas cylinder group and a gas pipeline. The gas cylinder group is connected to the gas hot oil generator through the gas pipeline. A gas control valve is also provided on the gas pipeline.

[0011] As a preferred technical solution, a right side accident oil pool and a left side accident oil pool are respectively provided on both sides of the oil pool on the top of the main oil tank, and the right side accident oil pool and the left side accident oil pool are both connected to the oil pool on the top of the main oil tank.

[0012] As a preferred technical solution, a circulation pump is provided on the first input pipeline, the first output pipeline, the second input pipeline, and the second output pipeline.

[0013] As a preferred technical solution, the first input pipeline includes an oil pipeline 1, on which a hot oil pump 1 is provided, the first output pipeline includes an oil return pipe 1, on which a return oil pump 1 is provided, the second input pipeline includes an oil pipeline 2, on which a hot oil pump 2 is provided, and the second output pipeline includes an oil return pipe 2, on which a return oil pump 2 is provided.

[0014] As an optimal technical solution, the main oil tank top oil pool is provided with a main oil tank top oil pool oil filling port and a main oil tank top oil pool oil return port. The main oil tank top oil pool oil filling port is connected with the insulated oil storage tank through an oil pipeline 1, and the main oil tank top oil pool oil return port is connected with the insulated oil storage tank through an oil return pipe 1. The right-side accident oil pool and the left-side accident oil pool are both provided with accident oil pool oil filling ports on both sides and accident oil pool oil return ports on both sides. The insulated oil storage tank is connected with the accident oil pool oil filling ports on both sides of the right-side accident oil pool through an oil pipeline 2. The insulated oil storage tank is also connected with the accident oil pool oil filling ports on both sides of the left-side accident oil pool through an oil pipeline 2. The accident oil pool oil return ports on both sides of the right-side accident oil pool and the left-side accident oil pool are connected with the insulated oil storage tank through an oil return pipe 2.

[0015] As a preferred technical solution, the right-side accident oil pool is also connected to the left-side accident oil pool through a connecting vessel, and flow meters are provided on the first input pipeline, the first output pipeline, the second input pipeline, and the second output pipeline.

[0016] As a preferred technical solution, an electric heater is connected to the top of the oil pillow.

[0017] A hot oil heating method applicable to a hot oil simulation system for a converter transformer fire extinguishing test comprises the following steps:

[0018] S1. Before the test, inject the test transformer oil into the insulation oil storage tank and the oil pillow respectively. The oil volume in the insulation oil storage tank should be greater than or equal to 16 tons, and the oil volume injected into the oil pillow should be 5 tons;

[0019] S2, cyclically heating the transformer oil in the heat-insulating oil storage tank, pausing after heating to about the first experimental value, and pausing after heating the oil pillow to the second experimental value;

[0020] S3. At the beginning of the test, add oil to the top oil pool of the main oil tank and the right and left accident oil pools until the top oil pool of the main oil tank is filled with 10.2 tons and the right and left accident oil pools are filled with 5.2 tons respectively. Then, determine whether the oil temperature in the top oil pool of the main oil tank, the right and left accident oil pools meets the requirement of not being lower than the set value;

[0021] S4. If the oil temperature in the oil pool at the top of the main oil tank is lower than the set value, the heating unit continues to heat until the oil temperature reaches the set value and then stops heating; if the oil temperature in the right accident oil pool and the left accident oil pool is lower than the set value, the heating unit continues to heat until the oil temperature in the right accident oil pool and the left accident oil pool is higher than the set value and then stops heating;

[0022] S5. When the oil temperatures in the top oil pool of the main oil tank, the right emergency oil pool, the left emergency oil pool and the oil pillow all meet the test conditions, enter the test ignition phase.

[0023] The beneficial effects of the present invention are:

[0024] (1) In the present invention, the oil temperature control method of first heating by the heating unit and then filling the oil and then fine-tuning the oil temperature has the advantages of high safety and more uniform oil temperature distribution, compared with the method of first filling the oil and then directly heating the oil pool on the top of the main oil tank and the accident oil pools on both sides with electric heating rods.

[0025] (2) In the present invention, gas is used to heat the oil pool on the top of the main oil tank and the accident oil pools on both sides. Compared with the use of electric heating, it is easier to achieve a greater heating power and reduce the overall heating time. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the overall structure provided by an embodiment of the present invention;

[0027] Figure numbers: 1. Gas cylinder group; 2. Gas pipeline; 3. Gas control valve; 4. Gas hot oil machine; 5. Hot oil pipe 1; 6. Hot oil pipe 2; 7. Insulated oil storage tank; 8. Hot oil pump 1; 9. Hot oil pump 2; 10. Oil pipeline 1; 11. Oil pipeline 2; 12. Right side accident oil pool; 13. Oil filling port of oil pool on top of main oil tank; 14. Oil filling ports of accident oil pool on both sides; 15. Oil pillow; 16. Electric heater; 17. Hot oil pipeline; 18. Oil pool on top of main oil tank; 19. Oil return port of oil pool on top of main oil tank; 20. Left side accident oil pool; 21. Oil return ports of accident oil pool on both sides; 22. Return oil pipe 1; 23. Return oil pipe 2; 24. Return oil pump 1; 25. Return oil pump 2. DETAILED DESCRIPTION

[0028] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] Example 1

[0030] See also Figure 1 A hot oil simulation system suitable for a converter transformer fire extinguishing test comprises a gas hot oil machine 4, an insulated oil storage tank 7, an oil pool 18 on the top of a main oil tank, a right accident oil pool 12, a left accident oil pool 20, an oil pillow 15, and an electric heater 16. The gas hot oil machine 4 is connected to the insulated oil storage tank 7. The oil stored in the insulated oil storage tank 7 can be transported to the gas hot oil machine 4 for heating and then transported to the insulated oil storage tank 7 again. The insulated oil storage tank 7 is connected to the oil pool 18 on the top of the main oil tank through a first input pipeline. The oil pool 18 on the top of the main oil tank is connected to the insulated oil storage tank 7 through a first output pipeline. The insulated oil storage tank 7 is connected with the right accident oil pool 12 and the left accident oil pool 20 through a second input pipeline. The right accident oil pool 12 and the left accident oil pool 20 are connected with the insulated oil storage tank 7 through a second output pipeline. The insulated oil storage tank 7, the main oil tank top oil pool 18, the right accident oil pool 12, the left accident oil pool 20 and the oil pillow 15 are all provided with temperature sensors. The oil pillow 15 is connected with the main oil tank top oil pool 18 through a hot oil pipeline 17. An electric heater 16 is fixed on the oil pillow 15, and the electric heater 16 heats the hot oil in the oil pillow 15.

[0031] See also Figure 1The gas hot oil machine 4 is connected to the insulated oil storage tank 7 through the hot oil pipe 1 5 and the hot oil pipe 2 6. One end of the hot oil pipe 1 5 and the hot oil pipe 2 6 is connected to the gas hot oil machine 4, and the other end is connected to the insulated oil storage tank 7. The hot oil pipe 1 5 is used to transport the heated stored oil to the insulated oil storage tank 7, and the hot oil pipe 2 6 is used to transport the stored oil in the insulated oil storage tank 7 to the gas hot oil machine 4 for heating. The gas hot oil machine 4 can be a high-power oil filter machine directly purchased from the market, or it can be a specially designed gas burner-oil heat exchanger.

[0032] See also Figure 1 , the first input pipeline, the first output pipeline, the second input pipeline, and the second output pipeline are all provided with a circulation pump, wherein the first input pipeline includes an oil delivery pipeline 10, on which a hot oil pump 8 is provided, the first output pipeline includes a return oil pipeline 22, on which a return oil pump 24 is provided, the second input pipeline includes an oil delivery pipeline 11, on which a hot oil pump 9 is provided, and the second output pipeline includes a return oil pipeline 23, on which a return oil pump 25 is provided;

[0033] The right side accident oil pool 12 and the left side accident oil pool 20 are respectively located on both sides of the main oil tank top oil pool 18, the plane where the bottom of the main oil tank top oil pool 18 is located is located above the plane where the bottom of the right side accident oil pool 12 and the left side accident oil pool 20 are located, and the plane where the top of the main oil tank top oil pool 18 is located is located below the plane where the bottom of the oil pillow 15 is located, and the bottoms of the right side accident oil pool 12 and the left side accident oil pool 20 are also connected through a connecting vessel, so that the oil volume of the right side accident oil pool 12 and the left side accident oil pool 20 is equivalent;

[0034] The main oil tank top oil pool 18 is provided with a main oil tank top oil pool oil filling port 13 and a main oil tank top oil pool oil return port 19. The main oil tank top oil pool oil filling port 13 is connected with the insulated oil storage tank 7 through an oil pipeline 10, and the main oil tank top oil pool oil return port 19 is connected with the insulated oil storage tank 7 through an oil return pipe 22. The right accident oil pool 12 and the left accident oil pool 20 are both provided with accident oil pool oil filling ports 14 on both sides and accident oil pool oil return ports 21 on both sides. The insulated oil storage tank 7 is connected with the accident oil pool oil filling ports 14 on both sides of the right accident oil pool 12 through an oil pipeline 2 11. The insulated oil storage tank 7 is also connected with the accident oil pool oil filling ports 14 on both sides of the left accident oil pool 20 through an oil pipeline 2 11. The accident oil pool oil return ports 21 on both sides of the right accident oil pool 12 and the left accident oil pool 20 are connected with the insulated oil storage tank 7 through an oil return pipe 23.

[0035] See also Figure 1The hot oil pump 1 8 and the hot oil pump 2 9 are respectively provided with flow counting functions or flow meters are arranged on the oil pipeline 10 and the oil pipeline 2 11. The flow of the return oil pump 24 should be the same as that of the hot oil pump 1 8 and have a flow counting function or a flow meter is arranged on the return oil pipe 1 22. The flow of the return oil pump 25 should be the same as that of the hot oil pump 2 9 and should have a flow counting function or a flow meter is arranged on the return oil pipe 23. The flow meters are commercially available.

[0036] See also Figure 1 The gas hot oil machine 4 is connected to the gas bottle group 1 through the gas pipeline 2, which is used to provide gas for the gas hot oil machine 4. The gas pipeline 2 is provided with a gas control valve 3, which can control the opening and closing of the gas pipeline 2 and the flow rate.

[0037] The test hot oil heating method comprises the following steps:

[0038] S1. Before the test, inject the test transformer oil into the insulation oil storage tank 7 and the oil pillow 15 respectively. The amount of oil injected into the insulation oil storage tank 7 should be greater than or equal to 16 tons, and the amount of oil injected into the oil pillow 15 should be 5 tons;

[0039] S2, open the gas control valve 3 and the gas hot oil generator 4, circulate and heat the transformer oil in the heat-insulating oil storage tank 7, pause after heating to about 170°C, and maintain the temperature within 170±5°C for standby, turn on the electric heater 16 to heat the oil pillow 15 to 90°C, pause, and maintain the temperature at 90±5°C for standby;

[0040] S3. At the beginning of the test, turn on the hot oil pump 1 8 and the hot oil pump 2 9 to fill the main oil tank top oil pool 18, the right side accident oil pool 12, and the left side accident oil pool 20 with oil respectively; when the main oil tank top oil pool 18, the right side accident oil pool 12, and the left side accident oil pool 20 are filled with 10.2 tons and 5.2 tons respectively, use the temperature sensor to determine whether the oil temperature in the main oil tank top oil pool 18, the right side accident oil pool 12, and the left side accident oil pool 20 meets the requirement of not less than 155°C;

[0041] S4. If the oil temperature in the oil pool 18 on the top of the main oil tank is lower than 155°C, the gas control valve 3, the gas hot oil generator 4, the hot oil pump 1 8 and the return oil pump 24 are opened at the same time until the oil temperature in the oil pool 18 on the top of the main oil tank is higher than 155°C and then stop; if the oil temperature in the right accident oil pool 12 and the left accident oil pool 20 is lower than 155°C, the gas control valve 3, the gas hot oil generator 4, the hot oil pump 2 9 and the return oil pump 2 25 are opened at the same time until the oil temperature in the right accident oil pool 12 and the left accident oil pool 20 is higher than 155°C and then stop;

[0042] S5. When the oil temperatures in the main oil tank top oil pool 18, the right side emergency oil pool 12, the left side emergency oil pool 20 and the oil pillow 15 all meet the test conditions, the test ignition stage can be entered.

[0043] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A hot oil simulation system suitable for commutation variable fire extinguishing test, characterized in that: It includes a heating unit, an insulated oil storage tank, an oil pool on the top of the main oil tank, a right-side emergency oil pool, a left-side emergency oil pool, and an oil pillow. The heating unit is connected to the insulated oil storage tank and can heat it; the oil pillow is connected to the oil pool on the top of the main oil tank, the insulated oil storage tank is connected to the oil pool on the top of the main oil tank through a first input pipeline and a first output pipeline, the insulated oil storage tank is connected to the right-side emergency oil pool and the left-side emergency oil pool through a second input pipeline, and the right-side emergency oil pool and the left-side emergency oil pool are connected to the insulated oil storage tank through a second output pipeline The insulated oil storage tank, the oil pool on the top of the main oil tank, the right emergency oil pool, and the left emergency oil pool are all equipped with temperature sensors; the heating unit heats the hot oil and injects it into the oil pool on the top of the main oil tank, the right emergency oil pool, and the left emergency oil pool. The hot oil temperature in the oil pool on the top of the main oil tank, the right emergency oil pool, and the left emergency oil pool is detected to see if it reaches the set value. If it does not reach the set value, the hot oil is circulated to the insulated oil storage tank for heating until the temperature in the oil pool on the top of the main oil tank, the right emergency oil pool, and the left emergency oil pool reaches the set value.

2. A hot oil simulation system suitable for converter fire extinguishing test according to claim 1, characterized in that: The heating unit includes a gas hot oil generator, which is connected to the heat-insulating oil storage tank through a first hot oil pipe and a second hot oil pipe.

3. A hot oil simulation system suitable for converter fire extinguishing test according to claim 2, characterized in that: The heating unit further comprises a gas cylinder group and a gas pipeline. The gas cylinder group is connected to the gas hot oil generator via the gas pipeline. A gas control valve is also provided on the gas pipeline.

4. The hot oil simulation system for converter fire extinguishing test according to claim 1 is characterized in that: A right side emergency oil pool and a left side emergency oil pool are respectively provided on both sides of the oil pool on the top of the main oil tank, and the right side emergency oil pool and the left side emergency oil pool are both connected to the oil pool on the top of the main oil tank.

5. The hot oil simulation system for converter fire extinguishing test according to claim 1 is characterized in that: The first input pipeline, the first output pipeline, the second input pipeline, and the second output pipeline are provided with a circulation pump.

6. The hot oil simulation system for converter fire extinguishing test according to claim 5, characterized in that: The first input pipeline includes an oil pipeline 1, on which a hot oil pump 1 is provided. The first output pipeline includes an oil return pipe 1, on which a return oil pump 1 is provided. The second input pipeline includes an oil pipeline 2, on which a hot oil pump 2 is provided. The second output pipeline includes an oil return pipe 2, on which a return oil pump 2 is provided.

7. The hot oil simulation system for converter transformer fire extinguishing test according to claim 6, characterized in that: The top oil pool of the main oil tank is provided with an oil filling port of the top oil pool of the main oil tank and an oil return port of the top oil pool of the main oil tank. The oil filling port of the top oil pool of the main oil tank is connected with the insulated oil storage tank through an oil pipeline 1, and the oil return port of the top oil pool of the main oil tank is connected with the insulated oil storage tank through an oil return pipe 1. The right-side accident oil pool and the left-side accident oil pool are both provided with accident oil filling ports on both sides and accident oil return ports on both sides. The insulated oil storage tank is connected with the accident oil filling ports on both sides of the right-side accident oil pool through an oil pipeline 2, and the insulated oil storage tank is also connected with the accident oil filling ports on both sides of the left-side accident oil pool through an oil pipeline 2. The accident oil return ports on both sides of the right-side accident oil pool and the left-side accident oil pool are connected with the insulated oil storage tank through an oil return pipe 2.

8. The hot oil simulation system for converter transformer fire extinguishing test according to claim 1 is characterized in that: The right side accident oil pool is also connected to the left side accident oil pool through a communicating vessel. Flow meters are provided on the first input pipeline, the first output pipeline, the second input pipeline, and the second output pipeline.

9. The hot oil simulation system for converter fire extinguishing test according to claim 1, characterized in that: The top of the oil pillow is connected with an electric heater.

10. A hot oil heating method suitable for a hot oil simulation system for a converter transformer fire extinguishing test according to any one of claims 1 to 9, characterized in that: The steps include: S1. Before the test, inject the test transformer oil into the insulation oil storage tank and the oil pillow respectively. The oil volume of the insulation oil storage tank should be greater than or equal to 16 tons, and the oil volume injected into the oil pillow should be 5 tons. S2, circulate heating the transformer oil in the heat-insulating oil storage tank, pause after heating to about the first experimental value, and pause after heating the oil pillow to the second experimental value; S3. At the start of the test, add oil to the main tank top oil pool and the right and left accident oil pools until the main tank top oil pool is filled with 10.2 tons and the right and left accident oil pools are filled with 5.2 tons respectively. Then, determine whether the oil temperatures in the main tank top oil pool, the right and left accident oil pools meet the requirement of not being lower than the set value. S4. If the oil temperature in the oil pool at the top of the main oil tank is lower than the set value, the heating unit continues to heat the oil until it reaches the set value and then stops heating. If the oil temperature in the right emergency oil pool or the left emergency oil pool is lower than the set value, the heating unit continues to heat the oil until the oil temperature in the right emergency oil pool or the left emergency oil pool exceeds the set value and then stops heating. S5. When the oil temperatures in the top oil pool of the main oil tank, the right emergency oil pool, the left emergency oil pool and the oil pillow all meet the test conditions, enter the test ignition phase.

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