Air-water cooler for wind turbines

Abstract

The present invention discloses an air-water cooler for a wind turbine generator, which belongs to the field of electrical technology and comprises a heat exchanger installed outside a nacelle of a wind turbine generator set and a water jacket installed outside the generator. The water jacket is connected to the heat exchanger through a circulation pipe to form a circulation loop. A propeller is rotatably installed in the circulation pipe, and the propeller is transmission-connected to a rotating shaft of the generator. The rotating shaft is driven to drive the propeller to rotate so as to realize a closed-loop circulation of the cooling liquid in the circulation pipe. The air-water cooler provided by the present invention, by transmission-connecting the propeller arranged in the circulation pipe with the rotating shaft of the generator, the circulation of the cooling liquid can be realized by driving the propeller to rotate through the rotating shaft, without relying on a circulation pump, thereby ensuring that during the rotation of the rotating blades of the wind turbine generator set, the cooling liquid is always in a circulation state and the generator is continuously cooled.

Description

Technical Field

[0001] The invention relates to a cooling device in the field of electrical technology, and in particular discloses an air-water cooler for a wind turbine generator. Background Art

[0002] The cooling system of a wind turbine is an important component of a wind power generation system. The quality of the cooling system is directly related to whether the wind turbine can operate safely and efficiently for a long time. The design of the cooling solution is flexible and diverse. Currently, wind turbines in mass production mostly use forced air cooling and liquid cooling. Among them, wind turbines with smaller power mostly use forced air cooling. Medium and large wind turbines generally need to use circulating liquid cooling to meet cooling requirements due to their large heat dissipation.

[0003] For example, the patent with announcement number CN201781375U, with announcement date of 2011-03-30, discloses a centralized water cooling device for wind turbines, comprising a water cooling unit, a circulating pump connected to the output port of the water cooling unit, a cooling medium delivery pipe connected to the output port of the circulating pump, and a cooling medium recovery pipe connected to the input port of the water cooling unit; a plurality of cooling devices are also connected in parallel between the output port of the cooling medium delivery pipe and the input port of the cooling medium recovery pipe; the plurality of cooling devices are respectively arranged in a plurality of corresponding wind turbines; the external radiators in the water cooling unit are centrally arranged to improve the adjustment ability of the cooling device, effectively save the energy consumption of the cooling device, and reduce the operating cost of the fan; it has a large refrigeration capacity and can meet the heat dissipation requirements of megawatt-class wind turbines; the number of external radiators can be adjusted according to actual conditions to improve operating efficiency.

[0004] The existing air-to-water cooler circulates the coolant to the heat exchange part, such as the cooling water jacket arranged outside the generator for heat exchange. The coolant flows through the water jacket to take away the heat generated by the generator and flows into the external heat exchanger. The external heat exchanger contacts the air for heat exchange, and the hot air after the heat exchange is taken away by the air flow. In this way, the circulation of the coolant is completely dependent on the circulation pump. Once the circulation pump fails, the operation of the wind turbine must be stopped and the circulation pump must be repaired, which affects the normal power generation. Summary of the invention

[0005] The purpose of the present invention is to provide an air-water cooler for a wind turbine generator.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] The air-water cooler for wind turbines comprises a heat exchanger installed outside the nacelle of the wind turbine and a water jacket installed outside the generator. The water jacket is connected to the heat exchanger through a circulation pipe to form a circulation loop. A propeller is installed in the circulation pipe for rotation. The propeller is connected to the shaft of the generator for transmission. The shaft is driven to drive the propeller to rotate to realize the closed-loop circulation of the coolant in the circulation pipe.

[0008] The above-mentioned air-water cooler has a connecting shaft arranged in the cabin parallel to the rotating shaft of the generator, one end of the connecting shaft is connected to the rotating shaft through a belt drive, and the other end of the connecting shaft extends into the circulation pipe and is fixedly connected to the propeller.

[0009] In the above-mentioned air-water cooler, a guide vane sleeve is connected in series at the position corresponding to the propeller on the circulation pipe, and an inlet pipe and an outlet pipe are connected to the guide vane sleeve. The inlet pipe is arranged along the axial direction of the guide vane sleeve, and the outlet pipe is arranged along the tangent direction of the guide vane sleeve.

[0010] The above-mentioned air-water cooler and heat exchanger are installed on the top of the cabin.

[0011] The above-mentioned air-water cooler has a pressure relief component connected in series on the circulation pipe.

[0012] In the above-mentioned air-water cooler, the pressure relief component is a pressure relief valve connected in series on the circulation pipe.

[0013] The pressure relief assembly of the air-to-water cooler includes a water storage barrel, a piston is arranged in the water storage barrel, and an elastic member is arranged in the water storage barrel for maintaining the piston in contact with the liquid surface of the coolant at all times.

[0014] In the above-mentioned air-water cooler, the lower part of the water storage barrel is connected with a drain pipe, and the height of the drain pipe is at the lowest point of the circulation loop.

[0015] The above-mentioned air-to-water cooler has a linear drive mechanism disposed in the water storage barrel, and an air hole is disposed on the upper portion of the water storage barrel. When the linear drive mechanism stops, the piston can float up and down in the water storage barrel. When the linear drive mechanism starts, the piston is driven to move up and down in the water storage barrel. A valve is connected in series to one end of the circulation pipe connected to the water storage barrel, and the valve can switch the connection between the circulation pipe and the water storage barrel to connection with the outside world.

[0016] The above-mentioned air-to-water cooler has a water inlet and a water outlet on the water storage barrel. The water inlet is higher than the water outlet, and the water outlet is higher than the drain pipe. The water outlet end of the heat exchanger is connected with the water inlet of the water storage barrel. The water outlet of the water storage barrel is connected with the water inlet pipe of the guide vane sleeve through a circulation pipe. The valve is installed at the position where the circulation pipe is connected to the water inlet.

[0017] In the above technical scheme, the air-water cooler provided by the present invention is connected to the rotating shaft of the generator by a propeller arranged in a circulation pipe. The circulation of the coolant can be achieved by driving the propeller to rotate through the rotating shaft without relying on a circulation pump, thereby ensuring that the coolant is always in a circulation state and continuously dissipates heat to the generator during the rotation of the rotating blades of the wind turbine set. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0019] Figure 1 A schematic diagram of installing an air-to-water cooler in a cabin according to an embodiment of the present invention;

[0020] Figure 2 A cross-sectional view of a water storage barrel when the piston provided in an embodiment of the present invention is at a first height;

[0021] Figure 3 A cross-sectional view of a water storage barrel when the piston provided in an embodiment of the present invention is at a second height;

[0022] Figure 4 A top view of the positional relationship between the generator and the connecting shaft provided in an embodiment of the present invention;

[0023] Figure 5 A partial cross-sectional view of a guide vane sleeve provided in an embodiment of the present invention;

[0024] Figure 6 The embodiment of the present invention provides Figure 2 The enlarged schematic diagram at A in the middle;

[0025] Figure 7 The embodiment of the present invention provides Figure 3 The enlarged schematic diagram of point B in the middle;

[0026] Figure 8 A schematic diagram of the structure of a suspension block provided in an embodiment of the present invention.

[0027] Description of reference numerals:

[0028] 1. Nacelle; 11. Gearbox; 12. Rotating blades; 2. Heat exchanger; 3. Generator; 31. Water jacket; 32. Rotating shaft; 4. Circulating pipe; 5. Propeller; 6. Guide vane sleeve; 61. Water inlet pipe; 62. Water outlet pipe; 7. Connecting shaft; 71. Belt; 8. Water storage tank; 801. Extrusion rod; 802. Chute; 81. Piston; 811. Through hole; 812. Suspension block; 8121 , pin hole; 8122, guide hole; 813, mounting groove; 814, guide rod; 82, first spring; 83, telescopic rod; 84, drain pipe; 85, air hole; 86, valve; 87, electric push rod; 88, water inlet hole; 89, water outlet hole; 9, limit piece; 91, limit pin; 911, pin head; 912, pin body; 92, limit rod; 93, second spring; 94, third spring. DETAILED DESCRIPTION

[0029] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0030] In the description of the present invention, unless otherwise specified, "multiple" means two or more than two; the terms "upper", "lower", "left", "right", "inner", "outer", "front end", "rear end", "head", "tail" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "connected" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0031] like Figure 1-Figure 8 As shown, the air-water cooler for the wind turbine 3 provided in the embodiment of the present invention comprises a heat exchanger 2 installed outside the nacelle 1 of the wind turbine set, and a water jacket 31 installed outside the generator 3. The water jacket 31 is connected to the heat exchanger 2 through a circulation pipe 4 to form a circulation loop. A propeller 5 is rotatably installed in the circulation pipe 4. The propeller 5 is transmission-connected to the rotating shaft 32 of the generator 3. The rotating shaft 32 is driven to drive the propeller 5 to rotate to realize the closed-loop circulation of the coolant in the circulation pipe 4.

[0032] Specifically, the wind turbine generator 3 includes an iron tower for support, a cabin 1 is installed on the upper end of the iron tower, and a rotating blade 12 is rotatably installed at one end of the cabin 1. Figure 1As shown, the interior of the nacelle 1 is equipped with components such as a gearbox 11 and a generator 3, wherein the input end of the gearbox 11 is connected to the rotating blades 12 through a transmission shaft, and the output end of the gearbox 11 is connected to the rotating shaft 32 of the generator 3. In this way, when the rotating blades 12 are driven to rotate by wind, the power can be transmitted to the gearbox 11 through the transmission shaft, and then transmitted to the rotating shaft 32 of the generator 3 after the gearbox 11 changes speed, and the conversion of mechanical energy into electrical energy is realized by using the law of electromagnetic induction; the air-water cooler proposed by the present invention has a main structure The heat exchanger 2 includes a heat exchanger 2, a water jacket 31, and a circulation pipe 4, wherein the heat exchanger 2 is installed outside the cabin 1 so that the heat exchanger 2 can be in contact with the outside air, so that the heat can be taken away by the flow of air while performing heat exchange, and the water jacket 31 is sleeved on the outer shell of the generator 3, the water jacket 31 is cylindrical, and the inner cavity of the water jacket 31 is spirally provided with a spiral pipe, the water outlet end of the heat exchanger 2 is connected to the water inlet pipe 61 of the spiral pipe on the water jacket 31 through the circulation pipe 4, and the water outlet pipe 62 of the spiral pipe is connected to the heat exchanger 2 through another circulation pipe 4. The water inlet end of the heat exchanger 2 is connected to the water inlet end of the heat exchanger 2, so as to form a circulation loop. The heat exchanger 2, the circulation pipe 4 and the spiral pipe are all filled with coolant. In order to prevent the coolant from freezing in cold areas, ethylene glycol aqueous solution can be used as the coolant. Different from the prior art, a propeller 5 is rotatably installed in the circulation pipe 4, and the propeller 5 is transmission-connected to the rotating shaft 32 of the generator 3. In this way, when the output shaft of the gear box 11 drives the rotating shaft 32 of the generator 3 to rotate, it can also drive the propeller 5 in the circulation pipe 4 to rotate, so that the coolant can be in the above-mentioned circulation loop. Continuously circulate and perform heat exchange, thereby achieving the purpose of cooling the generator 3; obviously, in actual use, the heat dissipation of the gear box 11 can also be achieved through the air-water cooler, such as installing an oil cooler (not shown in the figure) on the part of the circulation pipe 4 between the heat exchanger 2 and the water jacket 31, and continuously circulate the lubricating oil in the gear box 11 to the oil cooler through the oil pipe, and then circulate from the oil cooler to the gear box 11 to form a closed oil circuit, and cool the lubricating oil through the heat exchange between the oil cooler and the coolant in the circulation pipe 4.

[0033] The air-water cooler provided by the present invention is configured to connect the propeller 5 arranged in the circulation pipe 4 with the rotating shaft 32 of the generator 3 in a transmission manner. The circulation of the coolant can be achieved by driving the propeller 5 to rotate through the rotating shaft 32 without relying on a circulation pump, thereby ensuring that the coolant is always in a circulation state and continuously dissipates heat to the generator 3 during the rotation of the rotating blades 12 of the wind turbine set.

[0034] Furthermore, a connecting shaft 7 is provided in the cabin 1 parallel to the rotating shaft 32 of the generator 3, one end of the connecting shaft 7 is connected to the rotating shaft 32 via a belt 71, and the other end of the connecting shaft 7 extends into the circulation pipe 4 and is fixedly connected to the propeller 5.

[0035] Specifically, a connecting shaft 7 is rotatably installed in the cabin 1, and the connecting shaft 7 is arranged parallel to the rotating shaft 32 of the generator 3, and one end of the connecting shaft 7 is transmission-connected to the rotating shaft 32. Optionally, one end of the connecting shaft 7 and the corresponding position on the rotating shaft 32 are both provided with pulleys, and the same transmission belt 71 is provided on the outside of the two pulleys, so that when the rotating shaft 32 rotates, the connecting shaft 7 can be driven to rotate synchronously. Obviously, the connecting shaft 7 and the rotating shaft 32 can also be transmitted through a gear set or other transmission structure, which is not repeated here; when the connecting shaft 7 rotates driven by the rotating shaft 32, it drives the propeller 5 arranged in the circulation pipe 4 to rotate, and the coolant in the circulation pipe 4 is driven to flow through the propeller 5, wherein the structure of the propeller 5 is the same as the impeller of the water pump.

[0036] Preferably, a guide vane sleeve 6 is connected in series at a position corresponding to the propeller 5 on the circulation pipe 4, and an inlet pipe 61 and an outlet pipe 62 are connected to the guide vane sleeve 6. The inlet pipe 61 is arranged along the axial direction of the guide vane sleeve 6, and the outlet pipe 62 is arranged along the tangential direction of the guide vane sleeve 6.

[0037] Specifically, Figure 1 and Figure 4 and Figure 5 As shown, the circulation pipe 4 is connected in series with a guide vane sleeve 6, which has the same structure as the pump casing of the water pump. The guide vane sleeve 6 is connected with an inlet pipe 61 and an outlet pipe 62 (both connected to the circulation pipe 4). The inlet pipe 61 is installed along the axial direction of the guide vane sleeve 6, and the outlet pipe 62 is installed along the tangential direction of the guide vane sleeve 6. Obviously, in order to avoid interference between the connecting shaft 7 and the circulation pipe 4, Figure 1 In the embodiment, the connecting shaft 7 extends from the left side of the guide vane sleeve 6 into the guide vane sleeve 6 and is connected to the propeller 5 , while the water inlet pipe 61 is arranged on the right side of the guide vane sleeve 6 .

[0038] Furthermore, the heat exchanger 2 is installed on the top of the nacelle 1 .

[0039] Specifically, in order to minimize the obstruction to the air flowing toward the heat exchanger 2, in the present embodiment, the heat exchanger 2 is installed on the top of the cabin 1 to prevent the air flowing toward the heat exchanger 2 from being obstructed by the cabin 1 or the iron tower. In addition, in order to facilitate the inspection or maintenance of the heat exchanger 2, an inspection window (not shown in the figure) is provided on the top wall of the cabin 1 corresponding to the position of the heat exchanger 2, and the inspector can reach the top of the cabin 1 through the inspection window.

[0040] In another embodiment of the present invention, a pressure relief component is connected in series to the circulation pipe 4 .

[0041] Specifically, in actual use, due to the large temperature difference between summer and winter, especially in the north, the pressure inside the circulation pipe 4 is different in summer and winter during use. If the circulation pipe 4 is completely filled with coolant, it will easily cause excessive pressure in the circulation pipe 4 when the temperature is high in summer, such as above 35°, causing damage to the joints of the circulation pipe 4 and causing leakage. If the circulation pipe 4 is not completely filled with coolant, bubbles will exist in the circulation pipe 4, and the thermal conductivity of the coolant is greater than that of the air, which will reduce the heat transfer effect at the location of the bubbles and affect the use effect of the air-water cooler. In this embodiment, a pressure relief component is connected in series to the circulation pipe 4. Optionally, the pressure relief component is a pressure relief valve (not shown in the figure) connected in series to the circulation pipe 4. With this arrangement, when the pressure in the circulation pipe 4 increases in summer, the pressure relief of the pressure relief valve protects the pipeline of the circulation pipe 4, especially the joints of the circulation pipe 4 from leakage.

[0042] Furthermore, the pressure relief assembly includes a water storage barrel 8, a piston 81 is arranged in the water storage barrel 8, and an elastic member for maintaining the piston 81 always in contact with the liquid surface of the coolant is arranged in the water storage barrel 8.

[0043] Specifically, in the above embodiment, the pressure relief component is a pressure relief valve connected in series to the circulation pipe 4. However, when the pressure relief valve is in use, it realizes pressure relief by discharging air or coolant in the circulation pipe 4. This will cause the coolant in the circulation pipe 4 to gradually decrease as the number of pressure relief times increases. Although the amount of reduction is very small relative to the total amount of coolant, it will still cause bubbles in the circulation pipe 4, thereby affecting the use effect of the air-to-water cooler. In this embodiment, the pressure relief component includes a water storage tank 8, such as Figure 1As shown, the water storage barrel 8 is arranged in the cabin 1, and a piston 81 is arranged inside the water storage barrel 8, the piston 81 is arranged in the middle of the water storage barrel 8, and an elastic member for maintaining the position of the piston 81 in the water storage barrel 8 is arranged on the upper part of the water storage barrel 8, so that the piston 81 is always in contact with the liquid surface of the coolant. Optionally, the elastic member is a first spring 82 arranged on the upper part of the water storage barrel 8. In this embodiment, the two ends of the first spring 82 are respectively in contact with the top inner wall of the water storage barrel 8 and the upper surface of the piston 81, and a telescopic rod 83 is arranged between the piston 81 and the top inner wall of the water storage barrel 8. The first spring 82 is sleeved on the outside of the telescopic rod 83, the upper end of the telescopic rod 83 is connected to the top inner wall of the water storage barrel 8, and the lower end of the telescopic rod 83 is connected to the piston 81. Through the guidance of the telescopic rod 83 for the first spring 82, The position of the first spring 82 is limited, and two connecting holes for connecting to the circulation pipe 4 are opened on the water storage barrel 8 below the piston 81, so that the circulation pipe 4 can form a circulation loop with the lower space of the water storage barrel 8; with such a configuration, since the piston 81 can float up and down in the water storage barrel 8, and the lower surface of the piston 81 can always be in contact with the liquid surface of the coolant under the limitation of the first spring 82, when the coolant expands due to the increase in temperature and causes the pressure in the circulation pipe 4 to increase, the piston 81 will slide in the water storage barrel 8 to the side where the first spring 82 is located, that is, the upper part of the water storage barrel 8, under the pressure of the coolant, thereby making room for a certain amount of space, thereby reducing the probability of leakage at the connection positions of the circulation pipe 4 and the water storage barrel 8, the circulation pipe 4 and the heat exchanger 2, the water jacket 31 and the above-mentioned guide vane sleeve 6.

[0044] Furthermore, a drain pipe 84 is connected to the lower part of the water storage barrel 8, and the height of the drain pipe 84 is at the lowest point of the circulation loop.

[0045] Specifically, in actual use, although ethylene glycol itself has good antifreeze, anti-corrosion and heat conduction properties, as time goes by, the additives in the coolant will gradually be consumed, the chemical properties will change, and pollutants will accumulate. These factors will affect the efficiency of the cooling system. Therefore, the coolant needs to be replaced regularly to ensure the cooling effect of the air-water cooler on the generator 3. In order to facilitate the discharge of the coolant in the circulation pipe 4 and the water storage barrel 8, the lower part of the water storage barrel 8 is connected to a drain pipe 84, and the drain pipe 84 connects the lower part of the water storage barrel 8 with the outside world, such as Figure 2 As shown, the height of the drain pipe 84 is lower than the height of the circulation pipe 4, the heat exchanger 2 and the water jacket 31, so that the coolant can be discharged under the action of gravity. During the use of the air-to-water cooler, the drain pipe 84 is in a closed state, and a manual valve or an electric control valve can be used to achieve the closure of the drain pipe 84.

[0046] In another embodiment of the present invention, a linear drive mechanism is provided in the water storage barrel 8, and an air hole 85 is provided on the upper part of the water storage barrel 8. When the linear drive mechanism stops, the piston 81 can float up and down in the water storage barrel 8. When the linear drive mechanism starts, the piston 81 is driven to move up and down in the water storage barrel 8. One end of the circulation pipe 4 connected to the water storage barrel 8 is connected in series with a valve 86. The valve 86 can switch the connection between the circulation pipe 4 and the water storage barrel 8 to the outside world. For example, the valve 86 is a three-way valve, one of which is connected to the external environment.

[0047] Furthermore, a water inlet hole 88 and a water outlet hole 89 (the above-mentioned connecting holes) are provided on the water storage barrel 8. The water inlet hole 88 is higher than the water outlet hole 89, and the water outlet hole 89 is higher than the drain pipe 84. The water outlet end of the heat exchanger 2 is connected with the water inlet hole 88 of the water storage barrel 8. The water outlet hole 89 of the water storage barrel 8 is connected with the water inlet pipe 61 of the guide vane sleeve 6 through the circulation pipe 4. The valve 86 is installed at the position where the circulation pipe 4 is connected to the water inlet hole 88.

[0048] Furthermore, the linear drive mechanism includes an electric push rod 87 fixedly connected to the water storage barrel 8, the electric push rod 87 is arranged along the axial direction of the piston 81, the output end of the electric push rod 87 is fixedly connected to a telescopic rod 83, the lower end of the telescopic rod 83 is connected to the piston 81, and the outside of the telescopic rod 83 is covered with a first spring 82.

[0049] Specifically, during the process of replacing the coolant, the air-water cooler is in a pause state. In order to avoid excessive heating of the generator 3 and the like, and for safety reasons, during the process of replacing the coolant, the rotating blades 12 will be stopped by a brake installed in the nacelle 1, so that the rotating shaft 32 of the generator 3 is in a stopped state. In the above embodiment, since the circulation of the coolant is driven by the rotating shaft, when the rotating blades 12 stop, the rotating shaft and the rotating shaft 32 of the generator 3 both lose power and stop, which will cause the coolant in the circulation pipe 4 to be unable to be completely discharged. Even if the coolant discharge port is set at the lowest point of the circulation loop, some coolant will still exist in the bending section in the heat exchanger 2 and the water jacket 31; in this embodiment, an electric push rod 87 is provided inside the water storage barrel 8, such as Figure 2 and Figure 3 As shown, the electric push rod 87 is arranged along the axial direction of the piston 81. Different from the above-mentioned embodiment, in this embodiment, the telescopic rod 83 is fixed to the output end of the electric push rod 87, and the end of the telescopic rod 83 away from the electric push rod 87 is connected to the piston 81. The first spring 82 is sleeved on the outside of the telescopic rod 83. When the telescopic rod 83 is at the maximum extension, the two ends of the first spring 82 are in contact with the end of the electric push rod 87 and the piston 81 respectively. In addition, the water storage barrel 8 is provided with a water inlet hole 88 and a water outlet hole 89. Figure 2 and Figure 3As shown, the water inlet 88 is arranged higher than the water outlet 89, and the water outlet 89 is higher than the drain pipe 84, and the water outlet end of the heat exchanger 2 is connected with the water inlet 88 through the circulation pipe 4, and the water inlet pipe 61 of the liquid guide pipe is connected with the water outlet 89 through the circulation pipe 4, and the valve 86 is installed at one end of the circulation pipe 4 connected to the water inlet 88. Preferably, the valve 86 is a solenoid valve.

[0050] During the use of the air-water cooler, the electric push rod 87 is kept at the maximum extension, and at this time the piston 81 is above the water inlet hole 88 on the water storage barrel 8, and the telescopic rod 83 is at the maximum extension. At this time, if the coolant expands, the piston 81 can be pushed up and the telescopic rod 83 can be contracted, thereby increasing the storage space for the coolant in the water storage barrel 8 to reduce the pressure in the circulation pipe 4; and when the coolant needs to be replaced, the drain pipe 84 is first opened to release the coolant in the water storage barrel 8. When no coolant flows out of the water storage barrel 8, it indicates that only the coolant in the heat exchanger 2 and the bending section in the water jacket 31 has not been discharged. At this time, by switching the valve 86, the circulation pipe 4 corresponding to the valve 86 is no longer connected to the water inlet hole 88 of the water storage barrel 8, but is connected to the external environment, and the drain pipe 84 is closed. At this time, the electric push rod 87 is started, so that the electric push rod 87 pulls the piston 81 to move upward in the water storage barrel 8 through the telescopic rod 83. As the piston 81 continues to move upward, the pressure in the lower space of the water storage barrel 8 decreases, and the coolant remaining in the heat exchanger 2 and the water jacket 31 will be pressed into the lower part of the water storage barrel 8 for temporary storage under the action of the external air pressure, and then the drain pipe 84 is opened to discharge it. During the upward movement of the piston 81, the air in the upper part of the water storage barrel 8 will be squeezed and discharged outward through the air hole 85, and then the above process is repeated repeatedly. As the electric push rod 87 drives the piston 81 to move up and down in the water storage barrel 8 for many times, until the coolant remaining in the heat exchanger 2 and the water jacket 31 is completely discharged into the water storage barrel 8 and the remaining coolant is released through the drain pipe 84, new coolant can be added to the water storage barrel 8.

[0051] Furthermore, a through hole 811 is opened on the piston 81 along its own axial direction, and a suspended block 812 is arranged in the through hole 811. The suspended block 812 has a first position and a second position relative to the piston 81. A limiting member 9 is arranged in the piston 81, and the limiting member 9 is used to lock the suspended block 812 in the first position. The piston 81 has a first height and a second height in the water storage barrel 8. When the piston 81 is at the first height, the limiting member 9 releases the lock on the suspended block 812, and an extrusion rod 801 is arranged at a position corresponding to the second height in the water storage barrel 8.

[0052] Specifically, in the above embodiment, although the coolant in the circulation pipe 4, the heat exchanger 2 and the water jacket 31 can be completely discharged, it is not convenient to completely fill the circulation pipe 4, the heat exchanger 2 and the water jacket 31 with the coolant when adding new coolant; in this embodiment, a through hole 811 is opened on the piston 81, such as Figure 2 and Figure 3 As shown, the through hole 811 is opened along the axial direction of the piston 81, and a suspension block 812 is arranged in the through hole 811. The cross section of the suspension block 812 is T-shaped. Figures 6 to 8 As shown, the middle part of the suspension block 812 extends into the through hole 811. The suspension block 812 can be made of foam plastic material such as polyethylene or polystyrene foam. The suspension block 812 has a first position and a second position relative to the piston 81: when the liquid level of the coolant in the water storage barrel 8 is lower than the surface where the piston 81 is connected to the telescopic rod 83 ( Figure 2 and Figure 3 When the upper surface of the piston 81 in the drawing is shown, the suspension block 812 will contact the surface of the piston 81, thereby blocking the port of the through hole 811. At this time, the suspension block 812 is in the first position relative to the piston 81. When the liquid level of the coolant in the water storage barrel 8 is higher than the surface where the piston 81 and the telescopic rod 83 are connected, the suspension block 812 will be moved away from the piston 81 due to the buoyancy, so that the through hole 811 connects the upper and lower sides of the piston 81. At this time, the suspension block 812 is in the second position relative to the piston 81 or between the first position and the second position.

[0053] A limiting member 9 is further provided in the piston 81. Optionally, the limiting member 9 includes a limiting pin 91 provided along the radial direction of the piston 81. The limiting pin 91 can slide along its own axial direction in the piston 81. The limiting pin 91 includes a pin head 911 with a right-angle trapezoidal cross section and a pin body 912 with a rectangular cross section. The hypotenuse of the pin head 911 corresponds to one end of the suspension block 812 in the through hole 811, that is, at Figure 2 and Figure 3 In the view, the hypotenuse of the pin head 911 is inclined upward and cooperates with one end of the suspension block 812 in the through hole 811. The pin head 911 and the pin body 912 are connected as a whole through the limit rod 92. One end of the limit rod 92 is inserted into the pin body 912 and can be retracted into the pin body 912. Preferably, the limit rod 92 is a square rod body to prevent the pin head 911 and the pin body 912 from rotating relative to each other, which causes the angle of the inclined surface of the pin head 911 to deviate. The outer part of the limit rod 92 is sheathed with a second spring 93, and the second spring 93 is between the pin head 911 and the pin body. 912, and a third spring 94 for maintaining the overall position of the limit pin 91 is arranged in the piston 81. Optionally, an annular protrusion is formed on the outer wall of the pin body 912 along its circumference. A placement groove 813 for accommodating the third spring 94 is provided in the piston 81. The third spring 94 is placed in the placement groove 813, and a pin hole 8121 is provided in the portion of the suspension block 812 in the through hole 811. The pin hole 8121 cooperates with the pin head 911. In addition, during the stroke of the piston 81 moving axially along the water storage barrel 8, the piston 81 has a first height and a second height, such as Figure 2 and Figure 3As shown, the first height is lower than the second height, and when the piston 81 is at the first height, the extension of the electric push rod 87 is the largest, and when the piston 81 is at the second height, the electric push rod 87 is in a fully retracted state, an inclined groove 802 is provided at a position corresponding to the first height in the water storage barrel 8, and an extrusion rod 801 is provided at a position corresponding to the second height in the water storage barrel 8, the extrusion rod 801 is provided along the radial direction of the water storage barrel 8, and the extrusion rod 801 extends to just above the suspension block 812;

[0054] When the piston 81 is at the first height, the limit pin 91 corresponds to the inclined groove 802. At this time, the pin body 912 of the limit pin 91 extends into the inclined groove 802 under the elastic force of the third spring 94, and the pin head 911 is completely removed from the pin hole 8121 provided on the suspension block 812. That is, at this time, the limit pin 91 releases the lock on the suspension block 812.

[0055] When the piston 81 is driven to move from the first height to the second height, the pin body 912 is guided by the inclined groove 802 to gradually move toward the inside of the piston 81 and push the pin head 911 to move into the through hole 811. At this time, the following conditions exist:

[0056] If the suspension block 812 is at the first position at this time, the pin head 911 can extend into the pin hole 8121 on the suspension block 812 and lock the suspension block 812 at the first position;

[0057] If the suspension block 812 is not in the first position due to the buoyancy of the coolant (the suspension block 812 may be between the first position and the second position or in the second position due to the height of the coolant), the pin head 911 is blocked by the side wall of the suspension block 812 and cannot continue to extend into the through hole 811. At this time, the pin head 911 squeezes the limit rod 92 to move into the pin body 912 and squeezes the second spring 93 to deform.

[0058] When the piston 81 moves up to near the second height, if the suspension block 812 is in the first position, the suspension block 812 just contacts the extrusion rod 801 when the piston 81 moves to the second height;

[0059] When the piston 81 moves up to a position close to the second height, if the suspension block 812 is not in the first position, it will move from the second position to the first position under the obstruction of the squeezing rod 801 and be locked by the pin head 911. During this process, since the pin head 911 extends into the through hole 811, after the squeezing rod 801 blocks the suspension block 812, when the piston 81 continues to move to the second height, one end of the suspension block 812 in the through hole 811 squeezes the inclined surface of the pin head 911, causing the pin head 911 to move toward the pin body 912 and squeeze the second spring 93 to deform. When the pin head 911 is directly opposite to the pin hole 8121, it will extend into the pin hole 8121 under the action of the elastic force of the second spring 93 to lock the suspension block 812.

[0060] In the process of driving the piston 81 to move from the first height to the second height to draw the residual coolant in the circulation pipe 4, the heat exchanger 2 and the water jacket 31 to the lower part of the water storage barrel 8, since the liquid level of the coolant in the water storage barrel 8 is lower than the piston 81 (the coolant in the lower part of the water storage barrel 8 may also be completely discharged), at this time, the suspension block 812 is in the first position, and as the pressure in the lower part of the water storage barrel 8 gradually decreases, the suspension block 812 can fit more closely with the surface of the piston 81 to cover the through hole 811, thereby ensuring that the lower cavity of the water storage barrel 8 (the water storage barrel 8 is divided into an upper cavity and a lower cavity by the piston 81, Figure 2 and Figure 3 In the figure, the upper cavity is located above the piston 81, and the lower cavity is located below the piston 81) to form negative pressure;

[0061] When adding new coolant, the electric push rod 87 contracts and drives the piston 81 to move from the first height to the second height. The electric push rod 87 is closed before the suspension block 812 contacts the extrusion rod 801, so as to keep the piston 81 between the first height and the second height. At this height, the extrusion rod 801 does not squeeze the suspension block 812 to the first position, that is, the suspension block 812 can float under the buoyancy of the coolant so that the through hole 811 can connect the upper cavity and the lower cavity. The staff adds coolant into the upper cavity of the water storage barrel 8 through the air hole 85. In this process In the embodiment, the suspension block 812 moves from the first position to the second position under the action of buoyancy, and the coolant flows from the upper cavity to the lower cavity through the through hole 811. After the lower cavity is completely filled with coolant, the electric push rod 87 continues to shrink to the shortest state, so that the piston 81 continues to move to the second height. The suspension block 812 is squeezed to the first position by the squeezing rod 801, and the suspension block 812 is locked in the first position with the stop pin 91. Then, the electric push rod 87 extends and drives the piston 81 to move from the second height to the first height. In this process, the suspension block 812 remains in the first position. The piston 81 is in the position and blocks one end of the through hole 811 connected to the upper cavity. The coolant in the lower cavity is squeezed by the piston 81 into the circulation pipe 4, the heat exchanger 2 and the water jacket 31. In the process of the piston 81 moving from the second height to the first height, the coolant is continuously added to the upper cavity through the air hole 85. When the piston 81 moves to the first height, the suspension block 812 is in the unlocked state and moves from the first position to the second position under the buoyancy of the coolant. At this time, the electric push rod 87 contracts and drives the piston 81 to move from the first height to the second height again. Since the upper cavity and the lower cavity are in In the connected state, the coolant in the upper cavity can enter the lower cavity through the through hole 811 to ensure that the coolant in the lower cavity is always filled, thereby preventing the coolant in the circulation pipe 4 from flowing back into the lower cavity. When the piston 81 moves to the second height again, the suspension block 812 moves to the first position under the restriction of the extrusion rod 801 and is locked by the limit pin 91. The electric push rod 87 is then extended to drive the piston 81 from the second height to the first height, and this process is repeated many times until the lower cavity, the circulation pipe 4, the heat exchanger 2 and the water jacket 31 are completely filled with coolant.

[0062] In a specific implementation, the air hole 85 opened on the water storage barrel 8 can be located at the top of the water storage barrel 8. During the process of filling the coolant, both the upper cavity and the lower cavity can be filled with the coolant, so that the coolant can be replenished from the upper cavity to the lower cavity in time, and the moving distance of the piston 81 (the height difference between the first height and the second height) can be close to the maximum telescopic amount of the electric push rod 87; obviously, in order to facilitate the filling of the coolant, the coolant can fill the circulation pipe 4, the water jacket 31 and the heat exchanger 2, and an overflow hole can be set at the high point of the circulation loop, that is, the corresponding position on the heat exchanger 2, and whether the coolant flows out from the overflow hole can determine whether the coolant fills the circulation pipe 4, the heat exchanger 2 and the water jacket 31.

[0063] Preferably, in order to prevent the suspension block 812 from deviating or even escaping from the through hole 811 during the suspension process, a guide rod 814 is provided on the piston 81 to limit the suspension block 812. The guide rod 814 passes through the upper part of the suspension block 812 and is connected to the piston 81, and the guide rod 814 and the extrusion rod 801 are staggered front and back to avoid interference. A guide hole 8122 matching the guide rod 814 is provided at a position corresponding to the guide rod 814 on the suspension block 812. The diameter of the guide hole 8122 is larger than the diameter of the guide rod 814. A stopper is formed at the upper end of the guide rod 814 along its own circumference. The diameter of the stopper is larger than the diameter of the guide hole 8122 to prevent the suspension block 812 from escaping from the guide rod 814. In addition, the diameter of the portion of the suspension block 812 extending into the through hole 811 is smaller than the diameter of the through hole 811 to prevent the suspension block 812 from being unable to float when it is in the first position.

[0064] The above description is only by way of illustration of certain exemplary embodiments of the present invention. It is undoubted that those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. An air-water cooler for a wind turbine generator, comprising a heat exchanger installed outside the nacelle of the wind turbine generator set and a water jacket installed outside the generator, wherein the water jacket is connected to the heat exchanger through a circulation pipe to form a circulation loop, and is characterized in that: A propeller is installed for rotation in the circulation pipe, and the propeller is transmission-connected to the rotating shaft of the generator. The rotating shaft is driven to drive the propeller to rotate to realize the closed-loop circulation of the coolant in the circulation pipe. A connecting shaft is arranged in the cabin parallel to the rotating shaft of the generator, one end of the connecting shaft is connected to the rotating shaft through a belt drive, and the other end of the connecting shaft extends into the circulation pipe and is fixedly connected to the propeller. A pressure relief assembly is connected in series on the circulation pipe, and the pressure relief assembly includes a water storage barrel, a piston is arranged in the water storage barrel, and an elastic member for maintaining the piston in contact with the liquid surface of the coolant at all times is arranged in the water storage barrel, a drain pipe is connected to the lower part of the water storage barrel, and the height of the drain pipe is at the lowest point of the circulation loop, a linear drive mechanism is arranged in the water storage barrel, and an air hole is arranged on the upper part of the water storage barrel. When the linear drive mechanism stops, the piston can float up and down in the water storage barrel. When the linear drive mechanism is started, the piston is driven to move up and down in the water storage barrel. A first valve is connected in series to one end of the circulation pipe connected to the water storage barrel. The first valve can switch the connection between the circulation pipe and the water storage barrel to the outside world. A through hole is opened along the axial direction of the piston. A suspension block is arranged in the through hole. The suspension block has a first position relative to the piston. A limit piece is arranged in the piston. The limit piece is used to lock the suspension block in the first position. When the liquid level of the coolant in the water storage barrel is lower than the surface where the piston is connected to the telescopic rod, the suspension block is in the first position relative to the piston. The suspension block contacts the surface of the piston and blocks the port of the through hole. When the liquid level of the coolant in the water storage barrel is higher than the surface where the piston is connected to the telescopic rod, the suspension block is affected by buoyancy and moves away from the piston so that the through hole connects the upper and lower sides of the piston.

2. The air-water cooler for a wind turbine generator according to claim 1, characterized in that: A guide vane sleeve is connected in series at a position corresponding to the propeller on the circulation pipe, and a water inlet pipe and a water outlet pipe are connected to the guide vane sleeve. The water inlet pipe is arranged along the axial direction of the guide vane sleeve, and the water outlet pipe is arranged along the tangent direction of the guide vane sleeve.

3. The air-water cooler for a wind turbine generator according to claim 1, characterized in that: The heat exchanger is installed on the top of the nacelle.

4. The air-water cooler for a wind turbine generator according to claim 2, characterized in that: The pressure relief assembly is a pressure relief valve connected in series on the circulation pipe.

5. The air-water cooler for a wind turbine generator according to claim 2, characterized in that: The water storage barrel is provided with a water inlet hole and a water outlet hole. The water inlet hole is higher than the water outlet hole, and the water outlet hole is higher than the drain pipe. The water outlet end of the heat exchanger is connected with the water inlet hole of the water storage barrel, and the water outlet hole of the water storage barrel is connected with the water inlet pipe of the guide vane sleeve. The first valve is installed at the position where the circulation pipe is connected to the water inlet hole.

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