CN101183808A - Internal cooling self-circulation evaporative cooling wind turbine stator structure - Google Patents

Abstract

An inner-cooled self-circulation evaporative cooling wind power generator stator structure, the motor stator adopts hollow wires, or solid wires and hollow cooling copper rods (311) are installed in the stator slot, and the hollow stator wires (or hollow cooling copper rods) The cooling channel and the insulating joint (202), the gas collecting ring (204), the liquid collecting ring (201), and the air condenser (206) higher than the stator wire form a closed cooling channel, and the liquid is injected into the cooling channel to evaporate and cool medium. When the motor is running, the heat of the motor is transmitted to the liquid evaporative cooling medium, and the temperature of the liquid evaporative cooling medium rises accordingly. When the temperature of the medium reaches the saturation temperature under the corresponding pressure, the liquid evaporative cooling medium vaporizes, phase changes and absorbs heat, forming gas. The medium gas rises obliquely along the cooling channel and enters the air condenser 206, where it exchanges heat with the external natural wind, condenses and liquefies, and returns to the cooling channel of the stator hollow wire or the cooling copper rod for the next step. cycle.

Description

Internal cooling self-circulation evaporative cooling wind turbine stator structure

technical field

The invention relates to a stator structure of a megawatt-level and above large-scale direct-drive and semi-direct-drive wind power generators, in particular to an inner-cooled self-circulation evaporative cooling direct-drive and semi-direct-drive wind power generator.

Background technique

Wind power generation is the most mature technology in the utilization of renewable energy. In today's world energy crisis is becoming more and more serious, wind power generation has received great attention, and wind power generation technology has developed very rapidly. Wind power generation is through the rotation of the wind wheel under the action of wind force, the wind energy is converted into the mechanical energy of the wind wheel, which drives the generator to generate electricity. The schematic diagram of the structure of a large-scale direct-drive wind power generator is shown in Figure 1. It is mainly composed of an impeller 10 driven by the wind to generate power, a generator body 20 whose rotor follows the rotation of the impeller to generate electricity, and the impeller and the generator body are placed on a high-altitude platform. The supporting tower 30 constitutes.

At present, the power of wind power generators commonly used has exceeded the MW level, and the maximum can reach more than 5MW. When the wind turbine is running, losses will inevitably occur, mainly including core loss, winding loss, mechanical loss, etc. Most of these losses will eventually turn into heat, which will increase the temperature of various parts of the motor. Therefore, in order to ensure the long-term safe operation of the wind turbine, it is necessary to effectively cool the motor. Currently operating wind turbines generally adopt forced air cooling and liquid cooling cooling methods.

Forced air cooling refers to the cooling effect achieved by setting a fan inside the wind turbine to force blow air to the various components in the motor. The air-cooling system has a simple structure, low initial investment and operating costs, and is convenient for management and maintenance. However, its cooling effect is greatly affected by the temperature, and the cooling capacity is small. At the same time, because the engine room must be kept ventilated, wind, sand and moisture will erode the motor components, which will adversely affect the reliability of the motor and the working life of the motor. In addition, due to the low cooling capacity, it is generally only applied to wind turbines with a power below 750kW.

For wind turbines with large power, in order to make the motor work normally, a large amount of heat generated by the motor must be taken away in time to ensure the normal operating temperature of the motor. Currently, liquid cooling is mostly used for cooling. The basic structure of the liquid cooling system is to set a closed cooling passage on the main heat-generating parts of the motor (stator, control frequency converter, etc.), and use a cooling pump to make the liquid cooling medium flow through the cooling passage continuously. Absorbs heat, which then flows to an external radiator to dissipate the heat. The liquid cooling medium is mainly water, and the thermal conductivity of water is about 20 times that of air. Using water as the cooling medium will greatly improve the cooling effect. Its cooling effect is much better than air cooling.

However, the existing cooling methods for wind turbines have their own insurmountable shortcomings:

i Forced air cooling: the ventilation system of the motor is added, the wind friction loss is large, and the efficiency of the motor is low; the cooling is uneven, due to the relationship between the cooling passage, the stator core, winding and other structural components cannot be uniformly cooled; the cooling efficiency is low, making the motor Reduced power density, increased volume and weight; high noise, poor sealing performance of the motor, easy to be eroded by external dust and moisture, and reduce the service life of the motor.

ii Liquid cooling: Wind turbines work on towers that are tens of meters or even hundreds of meters above the ground, and must withstand the severe cold of minus 40°C in winter. The liquid cooling medium is mainly water, and antifreeze must be added to prevent the water from freezing. This antifreeze medium is highly corrosive to steel. Therefore, the cooling channel of the motor must be made of anti-corrosion stainless steel or other materials, or undergo cumbersome anti-corrosion treatment. These have greatly increased the processing difficulty of large-scale wind turbines and increased the cost. In addition, the long-term operation, due to the continuous penetration of water, can easily cause short circuits in the motor stator, and the safety and reliability of wind turbines have been seriously challenged. .

Evaporative cooling technology uses the principle of evaporative cooling medium liquid to vaporize and absorb heat to cool the motor. It is an efficient cooling method. Compared with traditional cooling methods, the latent heat of vaporization is large, the required flow rate is small, the temperature difference is small, and the cooling is uniform and comprehensive. The evaporative cooling medium has high insulation, is non-flammable and non-explosive, and has no corrosive effect on motor materials. It can directly cool the heating parts of the motor, such as motor wires and iron cores, quickly and reliably, ensuring the safe operation of the motor. Chinese patent 200510086794.9 "A Wind Power Generator Stator" adopts the stator structure of the immersion evaporative cooling wind power generator, that is, the stator parts of the motor are all immersed in the evaporative cooling medium for cooling. This cooling method is more suitable for motors with smaller diameters. For a motor with a larger diameter, if the immersion evaporative cooling structure is used, the reliability of the seal will be deteriorated. At the same time, a large amount of cooling medium is required, which greatly increases the cost of the motor. The diameter of the stator of direct-drive and semi-direct-drive wind turbines generally exceeds 2 meters, which is not suitable for immersion evaporative cooling structures.

Contents of the invention

The purpose of the present invention is to overcome the shortcomings of low cooling efficiency of the traditional air-cooling method and the need for anti-freezing in the water-cooling method. Aiming at large-scale direct-drive and semi-direct-drive wind power generation, an internal cooling self-circulating evaporative cooling wind power generator using evaporative cooling technology is proposed. Generator stator structure. The invention makes full use of the unique structural features of the large wind power generator to realize self-circulation evaporative cooling.

The present invention adopts following technical scheme:

The invention adopts pipeline internal cooling evaporative cooling technology, and the motor stator adopts hollow wires, or adopts solid wires and installs hollow cooling copper rods in the stator groove, and the cooling channel is connected with insulating joints, gas collecting ring pipes, liquid collecting ring pipes, And the air condenser whose installation position is higher than the stator wire of the connected motor forms a closed cooling channel. Liquid evaporative cooling medium is injected into the cooling channel. When the motor is running, the heat of the motor is transmitted to the liquid evaporative cooling medium. When the temperature of the medium reaches the saturation temperature under the corresponding pressure, the liquid evaporative cooling medium vaporizes, phase changes and absorbs heat, and forms gas. The medium gas rises obliquely along the cooling channel and enters the air condenser. In the air condenser, Exchange heat with external natural wind, condense and liquefy, return to the stator hollow wire, or the cooling channel of the hollow cooling copper rod for the next cycle, forming a self-circulation of evaporative cooling with internal cooling of the stator without external power.

In order to prevent the blades from colliding with the towers they support when rotating, large wind turbines require a sufficient safety distance between the blades and the towers. When designing, the impellers are raised by 3 to 5 degrees, and the wind power connected to the impellers The fuselage of the aircraft is also inclined vertically by 3 to 5 degrees, with the front high and the rear low. The hollow wire in the stator slot of the motor is also high at the front and low at the back. When the evaporative cooling medium in the hollow wire is heated and turned into gas, the gas will rise due to the low density of the medium gas, and enter the air condenser from the front end of the motor through the gas collecting ring. Then it condenses into a liquid and enters the hollow wire from the back end of the motor through the liquid ring pipe to form a circulation. The front of the motor is high and the rear is low, which provides the self-circulation power of the evaporative cooling cooling system and realizes self-circulation cooling.

The invention mainly includes stator hollow wire, hollow cooling copper rod, insulating joint, gas collecting ring pipe, liquid collecting ring pipe, air condenser and other components, and two structural modes of stator hollow wire or hollow cooling copper rod can be adopted:

1. The structure of the stator hollow wire: The stator hollow wire is a copper hollow wire with a square outer section, a round hole in the middle, and insulation on the outside of the wire. According to the design requirements of the motor stator winding, the stator hollow wire is uniformly fixed in the stator slot of the motor stator core along the circumference. The copper section of the hollow wire is the current channel section through which the current passes. The hollow cross section of the hollow wire is the cross section of the cooling channel, through which the evaporative cooling medium flows. The two ends of the wire are electrically connected with copper wires welded between the stator hollow wires in other stator slots according to the wiring requirements of the motor winding to form the end of the motor. There are cooling channel joints at both ends of the hollow conductor, and a sealed cooling channel is formed through the insulating joint and the outside. When the motor is working, the current generated by the generator passes through the hollow wire in the motor slot to generate heat, which is taken away by the evaporative cooling medium flowing in the hollow cooling channel of the hollow wire. In order to ensure that the working temperature of the motor remains within the allowable range of insulation. In addition, the heat generated by the hysteresis loss of the stator core of the motor when the motor is working can also conduct part of the heat through the stator hollow wire to the evaporative cooling medium to achieve partial cooling of the motor core.

2. The structure of the hollow cooling copper rod: the hollow cooling copper rod used in the present invention is used for cooling the motor when the stator adopts a solid wire. Its structure is similar to that of the stator hollow wire. It is hollow copper, with a square outer section and a round hole in the middle. The hollow section is the section of the cooling channel through which the evaporative cooling medium flows. There are cooling channel joints at both ends, forming a sealed cooling channel through insulating joints and the outside. When the hollow cooling copper rod is installed, it is installed in the middle of the solid conductor, and its two sides are in close contact with the solid conductor through the insulating layer to facilitate heat conduction. When the motor is working, the heat generated by the solid wire in the motor slot is conducted to the hollow cooling copper rod through the insulating layer, and then carried out through the phase change of the evaporative cooling medium in the hollow cooling copper rod.

The insulating joint used in the present invention is made of high-strength insulating material, and its tail end is connected with the gas collecting ring pipe or liquid collecting ring pipe through an insulating hose, and its front end is airtightly connected with the cooling channel joint welded on the hollow wire, and the motor The cooling medium channel of each hollow wire in the stator slot is connected and sealed with the outer gas collecting ring pipe and liquid collecting ring pipe to realize electro-hydraulic separation. The number of insulating joints is designed according to the number of hollow wires in the stator slot.

The gas-collecting ring pipe of the present invention is a large-diameter steel hollow circular pipe, and the diameter of the pipe is φ100--φ200mm according to the power of the motor. The larger the power, the thicker the pipe diameter. The gas collecting ring pipe is fixed on the front end of the stator core. According to the number of stator hollow wires, weld the joints at the corresponding positions along the circumference of the gas collecting ring, fix and seal the insulating hose, and connect the insulating joint at the other end of the insulating hose to the cooling channel of each hollow wire. The top of the gas collection ring is connected to the air inlet of the evaporative cooling air condenser through a pipe, and the medium gas generated by the evaporative cooling medium in the hollow wire cooling channel in the stator core slot enters the gas collection ring and passes through the gas collection ring. Rise up, enter the upper air condenser, and pass the heat out through the condenser.

The liquid collecting ring pipe in the present invention is a steel hollow ring pipe with a diameter of φ50mm, and the liquid collecting ring pipe is fixed on the rear end of the stator core. According to the number of stator hollow wires, weld joints at corresponding positions along the circumference of the liquid collecting ring, fix and seal the insulating hose, and connect the insulating joint at the other end of the insulating hose to the cooling channel of each hollow wire. The top of the collecting ring pipe is connected to the liquid return port of the evaporative cooling air condenser through a pipe, and the medium condensed by exchanging heat with the external air in the air condenser flows down the collecting ring pipe and is evenly distributed to each stator slot Stator hollow wires carry out the next cooling cycle, and a liquid inlet valve is set at the bottom of the liquid collection ring for adding and discharging evaporative cooling medium.

The air condenser in the present invention is a plate-fin or tube-fin condenser specially designed for evaporative cooling. The secondary cooling of the air condenser adopts the forced air cooling method, which can be realized in two ways: one is realized by an external additional fan, which needs to consume part of the power and increase part of the maintenance workload; the other case is, when conditions permit In some cases, the air condenser is placed on the top windward side outside the engine room of the generator set, and the natural wind is used as the secondary cooling air source. This makes full use of the external conditions when the wind turbine is working, that is, when the external wind force is strong, the cooling capacity of the condenser is also large, just as the power generated by the wind turbine is also large, and the heat generated by the generator is also large. When the external wind force is small, the cooling capacity of the condenser is small, just as the power generated by the wind turbine is also small, and the heat generated by the generator is also small. The external wind force can be fully utilized, and an exhaust valve is installed on the top of the air condenser to discharge the air in the cooling channel and reduce the pressure of the evaporative cooling system in case of failure.

The evaporative cooling medium used in the present invention is an evaporative cooling medium that is highly insulating, non-flammable and non-explosive, has a suitable boiling point, stable physical and chemical properties, and meets environmental protection requirements, such as Fla, 4310, 3000, etc. Since the wind turbine is in the open air, the ambient temperature in summer will reach 45°C. Under the sun, the temperature of the wind turbine itself can reach above 50°C. The medium used has a boiling point of about 70°C at room temperature, which can ensure The generator evaporative cooling system has a strong cooling capacity.

Compared with air cooling, the boiling heat transfer coefficient of the present invention when the evaporative cooling medium boils is several times or even tens of times higher than the convective heat transfer coefficient of single-phase fluid; Insulation, heat-generating components such as stator windings can pass through the evaporative cooling medium from the inside, and the cooling is uniform, comprehensive and rapid without local overheating. At the same time, the freezing point of the evaporative cooling medium is far below minus 45°C, so there is no problem of antifreezing in winter. Self-circulating evaporative cooling does not need a cooling pump at all, and can achieve maintenance-free operation.

The above-mentioned advantages of the present invention make it have broad application prospects in the field of wind power generators, especially in the field of large-scale permanent magnet direct-drive and semi-direct drive wind power generators.

Description of drawings

Figure 1 is a schematic diagram of the structure of a large direct-drive wind power generator, in the figure: 10 impellers, 20 generator bodies, 30 towers;

Figure 2a is a schematic diagram of the cooling structure of the internal cooling evaporative cooling wind turbine, in the figure: 201 liquid collecting ring pipe, 202 insulating joint, 203 hollow wire, 204 gas collecting ring pipe, 205 intake pipe, 206 air condenser, 207 stator Shell, 209 stator core, 210 liquid return pipe;

Figure 2b is a partial enlargement of the hollow wire joint. In the figure: 204 gas collecting ring pipe, 202 insulating joint, 203 hollow wire, 209 stator core, 213 coolant channel;

Figure 3a is a schematic diagram of the stator structure, in the figure: 31 iron core slot section, 203 hollow wire, 209 stator core;

Figure 3b is a schematic cross-sectional view of the stator structure, which is the right view of the A-A section in Figure 3a, in the figure: 31 iron core slot section;

Figure 3c is one of the schematic diagrams of the cross-sectional view of the stator core slot, in which: 203 hollow wire, 213 hollow wire coolant channel, 313 hollow wire insulating material, 314 slot wedge;

Figure 3d The second schematic diagram of the cross-sectional view of the stator core slot, 331 hollow cooling copper rod, 332 hollow cooling copper rod cooling liquid channel, 333 solid wire, 334 solid wire insulation material;

Figure 3e Schematic diagram of stator hollow wire structure; 213 hollow wire cooling liquid channel, 341 cooling channel connector;

Fig. 4 Sectional view of gas collecting ring pipe, 41 interface of insulating joint, 42 interface of air intake pipe;

Figure 5 Schematic diagram of the insulating joint structure; 51 ring pipe interface, 52 wire interface;

Fig. 6 Schematic diagram of grouping of motor cooling system. The figure is divided into three groups, and each dotted box is a subsystem;

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

FIG. 1 is a schematic structural diagram of a wind power generator. As shown in FIG. 1 , the wind power generator is mainly composed of three parts: a wind wheel 10 , a wind power generator body 20 , and a tower 30 . The wind generator body 20 is fixed on the tower 30, and its rotor rotates under the drive of the wind wheel 10. The rotor and the stator convert the mechanical energy of the rotor rotation into electrical energy through electromagnetic induction, and output current from the stator winding terminals. Due to the requirements of the mechanical structure between the wind turbine tower 30 and the blades of the impeller 10, the wind turbine impeller 10 is usually raised by 3-5 degrees, so that the wind generator body 20 connected to the impeller 10 is also raised by 3-5 degrees. Utilizing this structural feature, the present invention can realize unpowered self-circulation internal cooling evaporative cooling.

The present invention mainly includes stator hollow wire 203, hollow cooling copper rod 331, stator core 209, insulating joint 202, gas collecting ring pipe 204, liquid collecting ring pipe 201, air inlet pipe 205, air condenser 206 and other components.

The structure of the stator core 209, stator slots, and hollow conductors 203 is shown in Figure 3a and Figure 3b. The stator core 209 is made of laminated silicon steel sheets. Stator teeth and stator slots, hollow wires 203 are fixed in the stator slots, the cross section of which is shown in Figure 3c. The structure of the hollow wire is shown in Figure 3e. The hollow wire is a square copper tube, and the section in the motor stator slot is square. There is a circular hole in the middle for the cooling liquid channel 213, and there are cooling channel nozzles 341 at both ends to connect with the outside world. . There is an insulating material 313 between the hollow wires 203 and between the hollow wires 203 and the stator core 209 , and the hollow wires 203 are fixed by slot wedges 314 at the slots of the stator.

FIG. 4 is a schematic cross-sectional view of the gas collecting ring pipe 204, and the gas collecting ring pipe 204 is fixed at the front end of the stator. The diameter of the gas collecting ring pipe 204 is basically the same as the diameter of the slot of the stator core 209, corresponding to each slot there is an air inlet pipe interface 42, and the gas collecting ring pipe 204 passes through the insulating joint 202 and the hollow wire 203 in the stator slot. The cooling channel 213 is connected, the ring pipe interface 51 of the insulating joint 202 is connected with the insulating joint interface 41 of the gas collecting ring pipe 204, and the wire interface 52 of the insulating joint 202 is connected with the cooling channel nozzle 341 of the hollow wire 203 to form a closed cooling system. The channel is connected to the air condenser 206 through the inlet pipe interface 42 through the inlet pipe 205 .

The liquid collecting ring pipe 201 is similar in structure to the gas collecting ring pipe 204, and is installed at the rear end of the motor stator. Its top is connected to the air condenser 206 through the liquid return pipe 210, and then connected to the cooling channel nozzle at the rear end of the hollow wire 203 in the stator slot through the insulating joint 202, which acts as a liquid cooling medium cooled in the air condenser 206 Flow back into the cooling channel of the hollow wire 203 for the next cycle.

Fig. 5 is a structural schematic diagram of the insulating joint 202, the insulating joint 202 is made of high-strength insulating material, and is installed between the stator hollow wire 203 and the gas collecting ring pipe 204, or is installed between the stator hollow wire 203 and the liquid collecting ring pipe , its function is to connect the cooling channel, and prevent the current on the stator wire from flowing to the metal gas collector pipe 204 or liquid collector pipe 201, so as to isolate the current and the cooling liquid. The ring pipe interface 51 of the insulating joint 202 of the present invention is connected to the gas collecting ring pipe 204 or the liquid collecting ring pipe 201 through an insulating hose, and the wire interface 52 of the insulating joint 202 is airtightly connected with the cooling channel nozzle 341 on the hollow wire 203, The cooling medium channel of each hollow wire 203 in the stator slot of the motor is connected and sealed with the gas collecting ring pipe 204 and the liquid collecting ring pipe 201 to realize electro-hydraulic separation. The number of insulating joints 202 is determined by the number of hollow conductors in the stator slot. In FIG. 5 , the annular pipe interface 51 is connected to the gas collecting annular pipe 204 (or the liquid collecting annular pipe 201 ), and the wire interface 52 is connected to a plurality of stator hollow wires 203 .

The air condenser 206 of the present invention is a plate-fin or tube-fin condenser specially used for evaporative cooling. The cooling medium gas enters the air condenser 206 through the intake pipe, exchanges heat with the external secondary cooling air (generated by natural wind or fan) through the fins in the condenser 206, condenses into liquid, and then flows into the hollow conductor 203 through the liquid return pipe 210 for the next cycle.

The present invention has the following two implementation modes for different stator wires:

(1) Hollow wire self-circulation evaporative cooling

As shown in Fig. 2a, b, the stator hollow wire 203 of the wind power generator is uniformly fixed in the stator slot of the stator core 209 along the circumference. The stator hollow wire 203 is a copper hollow wire with a square outer section, a round hole in the center, and insulation on the outside of the wire. The copper part of the hollow wire 203 is a current channel through which the current passes. The central hole of the hollow wire 203 is a cooling channel through which the evaporative cooling medium flows. The front end of the cooling passage of the hollow wire 203 is connected to the gas collecting ring pipe 204 fixed on the front end of the motor stator through the insulating joint 202, and the rear end of the cooling passage of the hollow wire 203 is connected to the liquid collecting ring pipe 201 fixed on the rear end of the motor stator through the insulating joint 202 , the gas collecting ring pipe 204 is connected to the air condenser 206 fixed on the top of the stator housing 207 through the air inlet pipe 205, the air inlet surface of the air condenser 206 faces forward, and the external natural wind is used as the secondary cooling medium, and the air condenser 206 Condensate the evaporative cooling medium gas to cool the motor. The air condenser 206 is connected to the liquid collection ring pipe 201 through the liquid return pipe 210, and each connection end is sealed, thereby forming a closed cooling channel of the wind turbine stator conductor internal cooling evaporative cooling system. Inject liquid evaporative cooling medium into this closed cooling passage from the liquid inlet valve at the lower part of the liquid collecting ring pipe 201. The central hole cooling channel is filled with evaporative cooling liquid medium.

When the external wind increases and the impeller rotates, the wind generator starts to work, the motor stator winding generates current, outputs electric energy, and generates electromagnetic loss at the same time, the motor starts to heat up, and the temperature of the hollow wire 203 in the motor slot starts to rise. The evaporative cooling liquid medium in the middle cooling channel 213 of the hollow wire 203 absorbs the heat generated by the motor, and the temperature rises. When its temperature reaches the evaporation temperature, it continues to absorb heat to turn part of the medium into steam. Because the gas density is small, these gases will flow smoothly. The cooling channel 213 rises. Because the wind power generator is raised 3-5 degrees, the motor stator is placed at an inclination of 3-5 degrees in the horizontal direction, and the front end of the motor stator is higher than the rear end. Therefore, the vapor of the evaporative cooling medium will follow the cooling channel 213 in the hole of the hollow wire 203, obliquely Up through the insulating joint 202 into the front end of the gas ring pipe 204, then continue upward in the gas ring pipe 204, through the inlet pipe 205, into the air condenser 206, in the air condenser 206, the heat of the evaporation cooling medium gas is absorbed The external strong natural wind takes it away, condenses again, becomes liquid, flows down the liquid outlet pipe 210, enters the liquid collecting ring pipe 201 at the rear end of the motor stator, and then enters the hollow wire 203 center hole from the rear end through the insulating joint 202 at the other end The cooling channel 213 performs the next cycle, and so on, so as to realize the cooling of the motor.

This cooling method is suitable for wind turbines with large power and fewer stator winding turns.

(2) Solid wire self-circulation evaporative cooling

When the stator winding adopts solid wire 333, self-circulation evaporative cooling can also be realized. Its basic schematic diagram is similar to that in Figure 2, except that the hollow wire in Figure 2 is replaced by a hollow cooling copper rod. Figure 3d is a cross-sectional view of the stator slot of a self-circulating evaporative cooling motor with solid wires as the stator. As shown in Figure 3d, the structure of a row of vertical hollow cooling copper rods 331 placed in the middle of the stator slot is similar to that of the hollow wires shown in Figure 3e , is copper hollow, with a round hole in the middle, the central hole is a cooling channel, and the cooling channel flows an evaporative cooling medium. Only due to the difference in motor capacity, the diameter of the cooling channel 332 in the middle of the hollow cooling copper rod 331 is different. The solid wires 333 constituting the motor winding are closely arranged on both sides of the hollow cooling copper rod 331 in the stator slot. The outer surface of each solid wire 333 is wrapped with an insulating layer 334, and one side of the solid wire 333 is closely connected to the cooling copper rod 331 through the insulating layer 334. contact for heat transfer. The hollow cooling copper rod 331 constitutes a closed cooling channel through the insulating joint 202, the gas collecting ring pipe 204, the liquid collecting ring pipe 201, the gas outlet pipe, the liquid discharge pipe, and the air condenser 206, and the cooling channel is filled with an evaporative cooling liquid medium , to ensure that the cooling channel 332 of the hollow cooling copper rod is filled with medium.

When the motor is working, the motor generates heat, and the heat is transferred to the hollow cooling copper rod 331 through the contact surface of the solid wire 333 and the hollow cooling copper rod 331. The evaporative cooling medium inside the cooling channel 332 of the hollow cooling copper rod absorbs heat and the temperature rises. The evaporative cooling medium gas is generated, and the gas rises obliquely upward along the hole in the cooling channel 332 of the hollow cooling copper rod 331, enters the gas collecting ring pipe 204 at the front end of the motor stator, and then continues upward in the gas collecting ring pipe 204, passing through the intake pipe, Into the air condenser 206, in the air condenser 206, the heat of the evaporative cooling medium gas is taken away by the external strong natural wind, condensed again, becomes liquid, flows down the liquid outlet pipe, and enters the liquid collection ring pipe at the rear end of the motor stator 201, and then enter the cooling channel 332 of the hollow cooling copper rod 331 from the rear end to perform the next cycle, and so on, so as to realize the cooling of the motor.

This cooling method is suitable for wind turbines with a large number of stator winding turns.

The self-circulating evaporative cooling system formed by the above two methods can self-regulate with changes in the external environment. When the external wind force is weak, the motor generates less power and generates less heat, the cooling medium evaporates less, and the required condenser condensation capacity is also smaller, and at this time the condenser condensation capacity is also smaller. When the external wind force is strong, the power generated by the motor is large, the calorific value is large, the evaporation of the cooling medium is large, and the condensing capacity of the condenser is also large. At this time, due to the increase of the external wind force, the condensing capacity of the condenser is also large. increase in magnitude. Make full use of wind energy resources.

In the above two methods, when the power of the motor is too large and the heat generated by the motor is large, if a single air condenser is used, the volume and weight of the condenser will be large, and installation on the top of the motor will cause some problems. At this time, the motor cooling system can be divided into several separate systems, and the air condenser of the motor is also divided into several correspondingly, which are installed at a position higher than the cooling wire in the circumferential direction of the motor stator shell, as shown in Figure 6. It is divided into three groups in the figure, each group of air condenser and its corresponding (dotted circle) stator slot inner conductor form a self-circulating evaporative cooling system, and the difference from the above method is only the respective gas collection ring pipe and liquid collection ring pipe It is no longer a whole circular tube, but only an arc tube with a corresponding length.

Claims (5)

1. stator structure of inner cooling type self-circulation vaporization cooling wind power generator, comprise stator core (209), stator slot, stator conductor, it is characterized in that also comprising gas collection endless tube (204), air inlet pipe (205), liquid collecting endless tube (201), aerial condenser (206); Stator can adopt hollow conductor (203) or solid conductor to add hollow cooling copper rod (202) structure; Hollow conductor (203) is copper hollow conductor, and outer cross section is square, and circular hole is opened at the center, is insulated in the outside; The copper part of hollow conductor (203) is a current channel, and central duct is the cooling duct, cooling duct flow evaporation coolant; Stator core (209) inner headed face is tooth, groove structure, is stator tooth and stator slot alternately along interior round week, and hollow conductor (203) is fixed in the stator slot, carves (314) at stator rabbet by groove and fixes; There is insulating material (313) to be separated by between the hollow conductor (203) and between hollow conductor (203) and the stator core (209); Gas collection endless tube (204) is fixed in the motor stator front end; The diameter of gas collection endless tube (204) is consistent with the diameter of stator core 209 slot part positions, gas collection endless tube (204) is by hollow conductor (203) the inner cooling channel conducting in insulating joint (202) and the stator slot, form airtight cooling duct, be connected with aerial condenser (206) through air inlet pipe (205) by air inlet pipe interface (42); Insulating joint (202) is installed between stator hollow conductor (203) and the gas collection endless tube (204), or is installed between stator hollow conductor (203) and the liquid collecting endless tube (201); The tail end of insulating joint (202) is connected with gas collection endless tube (204) or liquid collecting endless tube (201) by flexible insulated hose, its front end connects with cooling duct on the hollow conductor (203) that mouth is airtight to be connected, and the coolant guiding channel of every hollow conductor (203) in the motor stator slot is connected with liquid collecting endless tube (201) with gas collection endless tube (204) and seals.

2. inner cooling type self-circulation vaporization cooling wind power generator according to claim 1, when it is characterized in that stator conductor adopts hollow conductor, hollow conductor (203) evenly is fixed in the stator slot of stator core (209) along circumference; The cooling duct front end of hollow conductor (203) is connected with the gas collection endless tube (204) that is fixed in the stator front end by insulating joint (202), the rear end, cooling duct of hollow conductor (203) is connected with the liquid collecting endless tube (201) that is fixed in the motor stator rear end by insulating joint (202), gas collection endless tube (204) is connected with the aerial condenser (206) that is fixed in stator case (207) top by air inlet pipe (205), aerial condenser (206) air intake surface face forward, utilize outside natural wind as the secondary coolant, in aerial condenser (206),, realize motor is cooled off to the evaporative cooling medium condensation of gas; Aerial condenser (206) is connected with liquid collecting endless tube (201) by liquid back pipe (210), and each link sealing forms the airtight cooling duct of aerogenerator stator conductor inner-cooled evaporative cooling system thus.

3. inner cooling type self-circulation vaporization cooling wind power generator according to claim 1, when it is characterized in that stator winding adopts solid conductor (333), hollow cooling copper rod (331) places in the middle of the stator slot, solid conductor (333) is closely arranged on stator slot hollow core cooling copper rod (331) both sides, the outer surface of every solid conductor (333) is enclosed with insulating barrier (334), and the one side of solid conductor (333) closely contacts with cooling copper rod (331) by insulating barrier (334); Hollow cooling copper rod (331) is by airtight cooling ducts of formation such as insulating joint (202) and gas collection endless tube (204), liquid collecting endless tube (201), escape pipe, discharging tube, aerial condenser devices (206).

4. according to claims 1 described inner cooling type self-circulation vaporization cooling wind power generator, it is characterized in that aerial condenser (206) is positioned over top windward side outside the cabin of generating set.

5. according to claims 1 described inner cooling type self-circulation vaporization cooling wind power generator, when the motor cooling system that it is characterized in that high-power wind-driven generator is divided into several separate payment, aerial condenser (206) is also corresponding be divided into several; Aerial condenser (206) be installed on motor stator shell circumferencial direction be higher than cool off the position of stator conductor, each aerial condenser (206) and its corresponding stator slot internal stator lead are formed a self-loopa evaporative cooling system.

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