A variable operating condition regulating residual pressure recovery device and system

Abstract

The present invention relates to the field of industrial fluid residual pressure recovery, and specifically relates to a variable-condition regulating residual pressure recovery device and system, which includes an impeller and a power generation device installed on a shaft. The upper end surface and the lower end surface of the permanent magnet rotor of the power generation device are provided with a first annular groove and a second annular groove, and a first pressure guiding hole communicating with the first annular groove is machined on the upper end cover of the stator; a second pressure guiding hole is provided on the side wall of the lower connecting pipe; the first pressure guiding hole and the second pressure guiding hole are connected through a first pressure guiding pipe; and a third pressure guiding hole communicating with the second annular groove is machined on the lower end cover of the stator; a fourth pressure guiding hole is provided on the side wall of the upper connecting pipe; the third pressure guiding hole and the fourth pressure guiding hole are connected through a second pressure guiding pipe. A pressure difference is formed between the high-pressure chamber of the first annular groove and the low-pressure chamber of the second annular groove, generating an axial force acting on the permanent magnet rotor. This axial force is opposite to the axial force generated by the impeller and is used to balance the axial force generated by the impeller, reduce the axial force of the permanent magnet rotor, and reduce the load on the rolling bearing.

Description

Technical Field

[0001] The present invention relates to the field of industrial fluid residual pressure recovery, and more specifically, to a variable-condition regulated residual pressure recovery device and system, which is an intelligent regulated and highly efficient residual pressure recovery device applicable to all working conditions of an industrial circulating cooling water system. Background Art

[0002] Industrial circulating cooling water systems are relatively common utility engineering systems with a very wide range of applications, covering various fields such as petrochemical, coal chemical, iron and steel, and fine chemical industries. In existing industrial circulating cooling water systems, both design institutes and manufacturers of cooling circulating water pumps have designed a large safety margin in the system. Also, due to the elevation difference between the high-position heat exchanger and the cooling tower, the return water pressure of the circulating cooling water system is relatively high. Most traditional cooling tower circulating water systems have a remaining pressure of 6 - 20 m in the return water, and it is necessary to reduce the return water pressure by reducing the opening of the return water valve to meet the demand for circulating cooling water to enter the cooling tower, as shown in Figure 1 . In order to reduce production costs, factories have started using water turbines to replace valves for pressure reduction in recent years to achieve the energy-saving goal of recovering the residual pressure of the return water.

[0003] From the public literature and the actual experience of the inventor, it is known that there are the following 5 ways to recover the residual pressure of circulating cooling water return. Recovery method 1: Install a water turbine 52 at the original position of the cooling tower fan motor to drive the fan to work, and retain the reducer, as shown in Figure 2 ; Recovery method 2: Install a water-driven fan (the water turbine is directly connected to the fan) on the cement platform of the original reducer, as shown in Figure 3 ; Recovery method 3: When the shaft power of the water turbine and the fan does not match, install a compensation motor (auxiliary motor 24) on the basis of the water-driven fan, as shown in Figure 4 ; Recovery method 4: The water turbine drives an external independent vertical generator 53 to generate electricity and connect to the grid, as shown in Figure 5 ; Recovery method 5: The water turbine drives an external independent horizontal generator to generate electricity and connect to the grid, as shown in Figure 6 .

[0004] For the solutions of water turbine driving the fan (recovery methods 1, 2, and 3), the installation position of the water turbine is at the top of the cooling tower more than 10 meters above the ground, which is inconvenient for installation, maintenance, etc. In addition, in winter or when the temperature is relatively low, the cooling tower fan stops running, and during this period, the purpose of recovering residual pressure and saving energy cannot be achieved. More importantly, when the water turbine or the compensation motor fails during operation, the cooling tower fan will not be able to run, resulting in a decrease in the heat dissipation capacity of the cooling tower and affecting normal production;

[0005] Both Recovery Method 1 and Recovery Method 2 are solutions where the turbine directly drives the fan. This solution can only be chosen to drive the fan when the shaft power output by the turbine is greater than the shaft power required by the fan and there is a certain surplus. Additionally, after the device has been operating for many years, it is common for the system pipe resistance to increase, the recovery pressure to drop, the heat transfer effect of the pipeline scaling to decline, the need to increase the circulation volume, the heat transfer efficiency of the cooling tower to decline, and the need to increase the air volume of the cooling tower. However, the increase in the circulation volume and the increase in the system pipe resistance will both lead to a drop in the return water pressure, causing the water head of the turbine to decrease, the output shaft power to decrease, the fan speed to decrease, and the air volume of the cooling tower to decrease, which cannot meet the demand for increasing the air volume of the cooling tower in the system, thus affecting the system process operation index and normal production. Moreover, when the turbine fails, the cooling tower fan will not be able to operate, and the decrease in the heat dissipation capacity of the cooling tower will also affect the system process operation index and normal production.

[0006] The emergence of Recovery Method 3 is to overcome some of the drawbacks of Recovery Method 1 and Recovery Method 2. By installing a compensating motor, it can make up for the situation where the shaft power output by the turbine is less than the shaft power required by the fan and the recovery pressure drops after the device has been operating for many years, and it can also achieve the situation of increasing the air volume of the cooling tower. However, for the above situation, the power margin of the configured compensating motor is very large. During normal operation, the compensating motor operates at a low power, and the operating efficiency and operating power factor of the compensating motor are very low. Additionally, when the compensating motor fails or the turbine fails, the cooling tower fan cannot operate at the designed speed or cannot operate, and the decrease in the heat dissipation capacity of the cooling tower will affect the system process operation index and normal production.

[0007] Recovery Method 4 and Recovery Method 5 completely overcome the shortcomings of Recovery Method 1, Recovery Method 2, and Recovery Method 3, and effectively solve the problems of the decrease in the heat dissipation capacity of the cooling tower caused by the failure of the turbine or the compensating motor during operation; the surplus pressure cannot be recovered during the shutdown of the cooling fan; the power margin of the compensating motor is too large; and after the device has been operating for many years, the speed of the turbine driving the fan decreases, resulting in a decrease in the heat dissipation capacity of the cooling tower.

[0008] However, during the one-year operation cycle of the circulating cooling water system, the operating flow rate and operating pressure need to be adjusted within a large range with the change of the air temperature, and the turbine needs to efficiently match these working conditions. The water turbine generator set of Recovery Method 4 cannot efficiently adapt to these adjusted working conditions, resulting in poor operating stability and energy-saving effect when the water turbine generator set operates away from the design point. Moreover, the water turbine of Recovery Method 4 is an axial flow water turbine. Due to the lack of an axial force balance structure inside, it can only be adapted to the surplus pressure recovery with a water head ≤ 10m.

[0009] Recovery method 5 is a horizontally installed mixed flow turbine, which can be designed with a movable guide vane structure to adjust the operating flow rate. However, the turbine generator set of recovery method 5 occupies too large an area, requires civil construction of a concrete foundation, has many pipe elbows, and has large water diversion losses, resulting in high overall investment costs. Summary of the invention

[0010] Therefore, the purpose of the present invention is to maximize the recovery of the return water residual pressure energy of the circulating cooling water system under all operating conditions without affecting the process operation of the circulating cooling water system, and to optimize the process operation mode of the circulating cooling water system (intelligent adjustment), and to invent a full-condition intelligent adjustment and high-efficiency residual pressure recovery equipment that occupies a small area and is easy to install, repair and maintain.

[0011] The present invention is realized by the following technical scheme: a variable working condition regulating residual pressure recovery device, comprising an impeller and a generator installed on a shaft, the generator comprising a permanent magnet rotor and a stator coil rotating simultaneously with the impeller, the impeller and the generator installed in a stator housing; a stator upper end cover is provided at the top of the stator housing, and a stator lower end cover is provided at the bottom;

[0012] The top of the stator upper end cover is connected with an upper connecting pipe, and the lower end of the stator lower end cover is connected with a lower connecting pipe;

[0013] The upper end surface of the permanent magnet rotor is provided with a first annular groove, and the upper end cover of the stator is processed with a first pressure-introducing hole connected with the first annular groove;

[0014] The side wall of the lower connecting pipe is provided with a second pressure-introducing hole; the first pressure-introducing hole and the second pressure-introducing hole are connected through a first pressure-introducing pipe, and the high pressure of the second pressure-introducing hole before decompression is introduced to the first annular groove through the first pressure-introducing pipe to form a high-pressure chamber;

[0015] The lower end surface of the permanent magnet rotor is provided with a second annular groove, and the lower end cover of the stator is processed with a third pressure-introducing hole connected with the second annular groove;

[0016] The side wall of the upper connecting tube is provided with a fourth pressure-introducing hole; the third pressure-introducing hole and the fourth pressure-introducing hole are connected through a second pressure-introducing tube, and the low pressure of the fourth pressure-introducing hole after decompression is led to the second annular groove through the second pressure-introducing tube to form a low-pressure chamber.

[0017] Furthermore, a supporting hub is provided in the lower connecting tube, the supporting hub is fixed to the inner wall of the lower connecting tube through a rib plate, and the lower end of the shaft is fixed in the supporting hub.

[0018] Furthermore, the stator coil includes a stator core fixed in a stator housing, and a stator winding installed in the stator core.

[0019] Furthermore, a main terminal box of the generator is installed on the outer wall of the stator housing.

[0020] Further, the impeller includes an impeller hub and impeller blades disposed on the impeller hub. The impeller hub is mounted on the shaft through a rolling bearing; a bearing locking nut is provided on the shaft above the rolling bearing; a bearing oil seal is provided on the shaft below the rolling bearing, and a mechanical seal is provided on the shaft below the bearing oil seal.

[0021] Further, movable guide vanes are evenly distributed on the circumference of the shaft below the impeller. Both ends of the movable guide vane are rotating shafts. One of the rotating shafts is in mating connection with a corresponding shaft hole on the support hub of the lower connecting pipe, and the other rotating shaft is in mating connection with a corresponding shaft hole on the outer wall of the lower end cover of the stator;

[0022] A swivel ring is provided on the outer wall of the lower end cover of the stator. The swivel ring is connected to the rotating shaft of the movable guide vane through a connecting rod joint bearing;

[0023] The swivel ring is connected to the piston rod of the actuator. The rotation of the swivel ring is driven by the telescopic movement of the piston rod, thereby changing the opening degree of the movable guide vane; the actuator calculates and controls the opening degree of the movable guide vane according to the flow signal, return water pressure signal or return water temperature signal of the liquid flow, so as to realize the intelligent adjustment of the operation flow of the circulating cooling water system.

[0024] Further, the cross-sectional area of the first pressure guiding pipe is more than twice the cross-sectional area of the first pressure guiding hole; the cross-sectional area of the second pressure guiding pipe is more than twice the cross-sectional area of the third pressure guiding hole.

[0025] Further, an upper connecting flange is provided at the top of the upper connecting pipe, and a first lower connecting flange is provided at the bottom of the upper connecting pipe. The upper connecting pipe is connected to the upper end cover of the stator through the first lower connecting flange;

[0026] A second lower connecting flange is provided at the bottom of the lower connecting pipe.

[0027] The present invention also provides a variable working condition regulating residual pressure recovery system, which includes a cooling tower. A cooling tower filler is provided in the cooling tower. A cooling tower water distributor is laid above the cooling tower filler. A fan is provided at the top of the cooling tower. A fan reducer is provided at the lower end of the fan. The fan reducer is connected to a fan motor on the cooling tower through a transmission shaft; the cooling tower water distributor is connected to a return water pipeline, and a variable working condition regulating residual pressure recovery device is installed on the vertical pipeline of the return water pipeline; the permanent magnet rotor of the residual pressure recovery device rotates under the action of the liquid flow along with the impeller, and electric energy is generated in the stator winding. The electric energy is directly used for the fan motor through a grid-connected system installed on site;

[0028] A first valve is provided at the water inlet of the residual pressure recovery device, and a third valve is provided at the water outlet of the residual pressure recovery device;

[0029] A bypass pipeline is provided between the water inlet and the water outlet of the residual pressure recovery device, and a second valve is provided on the bypass pipeline.

[0030] Furthermore, it also includes a grid-connected system installed on-site, which is used to control the operating speed of the residual pressure recovery device for variable working conditions adjustment. When the activity guide vane has different opening degrees, it enables the liquid flow angle to be efficiently matched with the installation angle of the impeller blades.

[0031] Compared with the prior art, the advantages of the present invention are as follows: A pressure difference is formed between the high-pressure chamber of the first annular groove on the upper end face of the permanent magnet rotor and the low-pressure chamber of the second annular groove on the lower end face of the permanent magnet rotor, generating an axial force acting on the permanent magnet rotor. This axial force is opposite to the axial force generated by the impeller, used to balance the axial force generated by the impeller, reduce the axial force of the permanent magnet rotor, reduce the load of the rolling bearing, and increase the selection range of the residual pressure recovery device; The multiple working conditions of the circulating water system are efficiently matched through the combined method of the activity guide vane and variable speed, and the operating conditions can be intelligently adjusted according to the flow signal, return water pressure signal, or return water temperature signal of the liquid flow; The electric energy generated by the residual pressure recovery device is consumed locally. The insufficient or excess electric energy is obtained through the fan motor cable or transmitted to the power grid in reverse, saving the cost of laying a separate cable, and the local consumption of electric energy also reduces the line loss. It has the characteristics of high full-condition operation efficiency, small impact on the process, intelligent adjustment of operating conditions, convenient installation, maintenance, and repair, and can adapt to the wide residual pressure head conditions of 4 - 20m; It is directly installed on the main pipeline of the cooling water return pipe, reducing the resistance loss caused by elbows and having a small floor area. Brief Description of the Drawings

[0032] Figure 1 It is a three-dimensional schematic diagram of the layout of the circulating water system in the prior art by reducing pressure through the return water valve.

[0033] Figures 2 - 6 It is a three-dimensional schematic diagram of the layout of the residual pressure recovery method of the circulating water system in the prior art.

[0034] Figure 7 It is a three-dimensional schematic diagram of the layout of the residual pressure recovery device for variable working condition adjustment of the present invention.

[0035] Figure 8 It is a three-dimensional sectional view of the residual pressure recovery device for variable working condition adjustment of the present invention.

[0036] Figure 9 It is a three-dimensional sectional view of the residual pressure recovery device for variable working condition adjustment of the present invention with a small opening degree (small flow condition) of the activity guide vane.

[0037] Figure 10 It is a partial sectional view of the residual pressure recovery device for variable working condition adjustment of the present invention.

[0038] Figure 11Schematic diagram of electric energy transmission for the variable operating condition regulating and residual pressure recovery system of the present invention;

[0039] Figure 12 Schematic diagram of the intelligent regulation of the operating condition for the variable operating condition regulating and residual pressure recovery system of the present invention;

[0040] Wherein: shaft 1, permanent magnet rotor 2, stator housing 3, upper stator cover 4, lower stator cover 5, movable guide vane 6, rotating shaft 7, swivel ring 8, connecting rod joint bearing 9, actuator 10, lower connecting pipe 11, support hub 12, rib plate 13, upper connecting pipe 14, upper connecting flange 15, first lower connecting flange 16, second lower connecting flange 17, impeller hub 18, impeller blade 19, permanent magnet 20, rolling bearing 21, mechanical seal 22, bearing oil seal 23, auxiliary motor 24, bearing locking nut 25, stator core 26, stator winding 27, main generator junction box 28, first annular groove 29, first pressure tapping hole 30, second pressure tapping hole 31, first pressure tapping pipe 32, second annular groove 33, third pressure tapping hole 34, fourth pressure tapping hole 35, second pressure tapping pipe 36, upper gland 37, lower gland 38, cooling tower 39, cooling tower packing 40, cooling tower water distributor 41, fan 42, fan speed reducer 43, transmission shaft 44, fan motor 45, return water pipeline 46, first valve 47, third valve 48, bypass pipeline 49, second valve 50, fan motor cable 51, water turbine 52, generator 53. Detailed implementation manners

[0041] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0042] For the convenience of description, the direction along the axis will be hereinafter referred to as the axial direction, and the direction perpendicular to the axis will be referred to as the radial direction.

[0043] Reference Figures 8 - 10, this embodiment provides a variable-condition regulating residual pressure recovery device, which includes an impeller and a power generation device installed on a shaft 1. The power generation device includes a permanent magnet rotor 2 and a stator coil that rotate simultaneously with the impeller. The impeller and the power generation device are installed in a stator housing 3; a stator upper end cover 4 is provided at the top of the stator housing 3, and a stator lower end cover 5 is provided at the bottom; the inner diameter of the stator upper end cover 4 is equal to the inner diameter of the permanent magnet rotor 2 (the outer diameter of the impeller blades), and the inner diameter of the stator lower end cover 5 (in the direction close to the permanent magnet rotor 2) is equal to the inner diameter of the permanent magnet rotor 2 (the outer diameter of the impeller blades), so that the permanent magnet rotor 2 rotates between the stator upper end cover 4 and the stator lower end cover 5; an axial gap is formed between the lower end surface of the stator upper end cover 4 and the upper end surface of the permanent magnet rotor 2. This axial gap should be as small as possible on the premise of ensuring no rubbing during operation, generally taking 0.5 - 1.5 mm; an axial gap is formed between the upper end surface of the stator lower end cover 5 and the lower end surface of the permanent magnet rotor 2. This axial gap should be as small as possible on the premise of ensuring no rubbing during operation, generally taking 0.5 - 1.5 mm;

[0044] A first annular groove 29 is provided in the middle of the inner diameter and outer diameter of the upper end surface of the permanent magnet rotor 2. At the position of the lower end surface of the stator upper end cover 4 corresponding to the first annular groove 29, a first pressure guiding hole 30 is provided, and a second pressure guiding hole 31 is provided on the side wall of the lower connecting pipe 11; the first pressure guiding hole 30 and the second pressure guiding hole 31 are connected through a first pressure guiding pipe 32; the high pressure of the second pressure guiding hole 31 before pressure reduction is led to the first annular groove 29 through the first pressure guiding pipe 32 to form a high-pressure chamber.

[0045] A second annular groove 33 is provided in the middle of the inner diameter and outer diameter of the lower end surface of the permanent magnet rotor 2. At the position of the upper end surface of the stator lower end cover 5 corresponding to the second annular groove 33, a third pressure guiding hole 34 is provided, and a fourth pressure guiding hole 35 is provided on the side wall of the upper connecting pipe 14; the third pressure guiding hole 34 and the fourth pressure guiding hole 35 are connected through a second pressure guiding pipe 36;

[0046] The low pressure of the fourth pressure guiding hole 35 after pressure reduction is led to the second annular groove 33 through the second pressure guiding pipe 36 to form a low-pressure chamber. A pressure difference is formed between the high-pressure chamber of the first annular groove 29 on the upper end surface of the permanent magnet rotor 2 and the low-pressure chamber of the second annular groove 33 on the lower end surface of the permanent magnet rotor 2, generating an axial force acting on the permanent magnet rotor 2. This axial force is opposite to the axial force generated by the impeller and is used to balance the axial force generated by the impeller, reduce the axial force of the permanent magnet rotor 2, and reduce the load on the rolling bearing 24.

[0047] In this embodiment, in order to ensure that the pressure difference formed between the high-pressure chamber and the low-pressure chamber is sufficient, the cross-sectional area of the first pressure guiding pipe 32 is more than twice the cross-sectional area of the first pressure guiding hole 30; the cross-sectional area of the second pressure guiding pipe 36 is more than twice the cross-sectional area of the third pressure guiding hole 34.

[0048] As a preferred embodiment of this embodiment, the actuator 10 is preferably a pneumatic or electric actuator with a feedback signal, and a positioner with a feedback signal is additionally installed, which can be remotely controlled. The actuator automatically controls the opening of the movable guide vane 6 through the operation of the PLC controller according to the flow signal or the return water pressure signal of the circulating cooling water system operation, so as to change the operation condition of the circulating cooling water system and realize the intelligent adjustment of the operation flow of the circulating cooling water system. When the value of the on-line flowmeter is greater than the given flow, or the value of the on-line return water pressure transmitter is less than the given return water pressure, the PLC controller outputs a command to close the opening of the movable guide vane 6. On the contrary, the PLC controller outputs a command to open the opening of the movable guide vane 6 until the deviation between the value of the on-line flowmeter and the given flow value is within the set range, or the deviation between the value of the on-line return water pressure transmitter and the given return water pressure value is within the set range. According to the use requirements, the flow adjustment or the return water pressure adjustment can also be changed to the return water temperature adjustment (as Figure 12 shown); the actuator 10 is simplified to handwheel adjustment, and the opening of the movable guide vane 6 is manually adjusted through the handwheel. Although the intelligent adjustment of the operation condition of the circulating water system cannot be realized, the equipment cost can be reduced.

[0049] In an embodiment of the present application, a lower connecting pipe 11 is connected to the lower end of the stator lower end cover 5. There is a support hub 12 inside the lower connecting pipe 11. The support hub 12 is fixed to the inner wall of the lower connecting pipe 12 through a rib plate 13. The cross section of the rib plate 13 is a streamline shape conducive to water flow. A shaft 1 is fixed in the inner hole of the support hub 12, and the shaft 1 is a stationary part.

[0050] In another embodiment of the present application, an upper connecting pipe 14 is connected to the top of the stator upper end cover 4, and a lower connecting pipe 11 is connected to the bottom of the stator lower end cover 5 through a flange. An upper connecting flange 15 is provided at the top of the upper connecting pipe 14, and a first lower connecting flange 16 is provided at the bottom of the upper connecting pipe 14. The upper connecting pipe 14 is connected to the stator upper end cover 4 through the first lower connecting flange 16;

[0051] A second lower connecting flange 17 is provided at the bottom of the lower connecting pipe 11. The upper connecting pipe 14 and the lower connecting pipe 11 are connected to the return water pipeline through the upper connecting flange 15 and the second lower connecting flange 17.

[0052] As a specific embodiment of the present application, the impeller includes an impeller hub 18. The outer circumference of the impeller hub 18 is provided with impeller blades 19 for recovering residual pressure energy. A permanent magnet rotor 2 is provided on the outer circumference of the impeller blades 19, and permanent magnets are evenly embedded on the outer circumference of the permanent magnet rotor 2; the impeller hub 18 is installed on the shaft 1 through a rolling bearing 21; along the direction of the water flow ( Figure 8(The direction of the arrow in the figure is the direction of the water flow.) A mechanical seal 22, a bearing oil seal 23, a rolling bearing 24 lubricated with thin oil, and a bearing locking nut 25 are successively installed on the shaft 1; in this embodiment, the rolling bearing 24 uses grease lubrication to reduce the leakage of thin oil lubrication through the bearing oil seal 23; the inner ring of the rolling bearing 24 is installed on the shaft 1, and the outer ring of the rolling bearing 24 is installed in the inner hole of the impeller hub 18;

[0053] The impeller hub 18, the impeller blades 19 for recovering residual pressure energy, and the permanent magnet rotor 2 together form an integral impeller. A stator coil corresponding to the permanent magnet rotor 2 is arranged outside the permanent magnet rotor 2. The stator coil includes a stator iron core 26. The stator iron core 26 is installed in the inner hole of the stator housing 3. The inner diameter of the stator iron core 26 and the outer diameter of the permanent magnet rotor 2 form a radial gap. This radial gap should be as small as possible on the premise of ensuring that the stator iron core 26 and the permanent magnet rotor 2 do not rub during operation, so as to reduce the magnetic circuit air gap, generally taking 1 - 2 mm; the stator winding 27 is installed in the stator iron core 26; the impeller rotates under the action of water flow, and the electric energy generated in the stator coil is directly used by the fan motor through the grid-connected system installed on site. Preferably, a main generator junction box 28 is installed on the outer wall of the stator housing 3 for connecting the power generation device and the grid-connected system.

[0054] In another embodiment of the present application, movable guide vanes 6 are evenly distributed on the circumference of the support hub 12 below the impeller for guiding the water flow into the impeller;

[0055] Both ends of the movable guide vane 6 are rotating shafts 7. One of the rotating shafts 7 is in fit connection with the corresponding shaft hole on the lower connecting pipe support hub 12, and the other rotating shaft 7 is in sealed fit connection with the corresponding shaft hole on the outer wall of the lower end cover of the stator, and the movable guide vane 6 can be driven to rotate by rotating the extending rotating shaft 7;

[0056] A swivel ring 8 is provided on the outer wall of the lower end cover 5 of the stator. The swivel ring 8 is connected to the extending rotating shaft 7 through a connecting rod joint bearing 9; both the connecting rod joint bearing 9 and the swivel ring 8 and the extending rotating shaft 7 are connected in a rotating manner;

[0057] The swivel ring 8 is connected to the piston rod of the actuator 10. The telescopic movement of the piston rod of the actuator 10 will control the swivel ring 8 to rotate around the lower end cover 5 of the stator, driving the structure of the connecting rod joint bearing 9 installed on the swivel ring 8 to act, thereby driving the movable guide vane 6 to rotate, so as to control the opening degree of the movable guide vane 6 and control the liquid flow rate entering the impeller. The change in the opening degree of the movable guide vane 6 changes the angle (liquid flow angle) of the liquid flow entering the impeller blades. In this embodiment, the operating speed of the residual pressure recovery device under variable working conditions can be controlled through the grid-connected system installed on site. At different opening degrees of the movable guide vane 6, different operating speeds are matched to make the liquid flow angle match the impeller blade setting angle efficiently, so that the residual pressure recovery device can operate efficiently under different working conditions, and the speed of the residual pressure recovery device can be adjusted through the grid-connected system.

[0058] In another embodiment of the present application, an upper gland 37 that is beneficial to water flow is provided at the top of the impeller hub 18, and a lower gland 38 that is beneficial to water flow is provided at the bottom of the support hub 12.

[0059] The residual pressure recovery device of the present invention is developed according to the above situation, mainly aiming at the efficient recovery of multi-condition residual pressure in the circulating water system, but is also applicable to other occasions with liquid residual pressure, such as: it can be installed in places with liquid residual pressure such as water channels, ditches, small rivers, dam discharges, etc. where there is a height difference. Taking the industrial circulating cooling water system as an example in this embodiment, a variable-condition regulating residual pressure recovery system includes a cooling tower 39, a cooling tower packing 40 is provided in the cooling tower 39, a cooling tower water distributor 41 is laid above the cooling tower packing 40, a fan 42 is provided at the top of the cooling tower 39, a fan reducer 43 is provided at the lower end of the fan 42, and the fan reducer 43 is connected to the fan motor 45 on the cooling tower 39 through a transmission shaft 44; the cooling tower water distributor 41 is connected to a return water pipe 46, and the return water pipe 46 has a vertical pipe section. The residual pressure recovery device in the above embodiment is installed on the vertical pipe of the return water pipe 46, and it is preferably installed at a position close to the ground or platform in the middle of the water pipe. The closer the installation position is to the ground or platform, the more convenient it is for maintenance. A first valve 47 is provided on the return water pipe 46 in the water inlet direction of the residual pressure recovery device to cut off the incoming flow during the maintenance of the residual pressure recovery device. Although the cooling tower cannot operate when the residual pressure recovery device fails, this method can reduce construction costs, reduce the floor area, and lower the overall cost.

[0060] The permanent magnet rotor 2 rotates with the impeller under the action of water flow to form a rotating magnetic field. The stator coil cuts the magnetic force lines to induce an electromotive force, thus converting the rotational mechanical energy of the impeller into electrical energy, and directly supplying the electrical energy to the fan motor through the grid-connected system installed on-site. When the electrical energy generated by the residual pressure recovery device is greater than the electrical energy required by the fan motor, the excess electrical energy is reversely transmitted through the fan motor cable 51 to other devices in the subnet for consumption, or directly reversely transmitted to the power grid; when the electrical energy generated by the residual pressure recovery device is less than the electrical energy required by the fan motor, power is taken forward through the fan motor cable 51 to make up the electrical energy difference (for the reference of the electrical energy transmission of the liquid flow residual pressure recovery system, see the appendix Figure 11 ). The grid-connected system is used to control the operating speed of the variable-condition regulating residual pressure recovery device, and to efficiently match the liquid flow angle with the impeller blade setting angle at different movable guide vane openings.

[0061] As a preferred embodiment, a third valve 48 is provided on the return water pipe 46 after the liquid passes through the residual pressure recovery device. In order to eliminate the influence on the process when the residual pressure recovery device fails, a bypass pipe 49 is provided between the water inlet and the water outlet of the return water pipe 46 where the residual pressure recovery device is installed, and a second valve 50 is installed on the bypass pipe. When the residual pressure recovery device fails, the second valve 50 on the bypass pipe 49 is used to reduce the pressure to the process requirements.

[0062] Although the embodiments of the present invention have been shown and described, for those of ordinary skill in the art, it can be understood that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A variable-condition regulating residual pressure recovery device, comprising an impeller and a power generation device mounted on a shaft. The power generation device includes a permanent magnet rotor and a stator coil that rotate simultaneously with the impeller. The impeller and the power generation device are mounted inside a stator housing. The top of the stator housing is provided with a stator upper end cover, and the bottom is provided with a stator lower end cover. It is characterized in that: The top of the stator upper end cover is connected with an upper connecting pipe, and the bottom of the stator lower end cover is connected with a lower connecting pipe; The upper end surface of the permanent magnet rotor is provided with a first annular groove, and a first pressure guiding hole communicating with the first annular groove is machined on the stator upper end cover; The side wall of the lower connecting pipe is provided with a second pressure guiding hole; the first pressure guiding hole and the second pressure guiding hole are connected by a first pressure guiding pipe, and the high pressure of the second pressure guiding hole before pressure reduction is led to the first annular groove through the first pressure guiding pipe to form a high-pressure chamber; The lower end surface of the permanent magnet rotor is provided with a second annular groove, and a third pressure guiding hole communicating with the second annular groove is machined on the stator lower end cover; The side wall of the upper connecting pipe is provided with a fourth pressure guiding hole; the third pressure guiding hole and the fourth pressure guiding hole are connected by a second pressure guiding pipe, and the low pressure of the fourth pressure guiding hole after pressure reduction is led to the second annular groove through the second pressure guiding pipe to form a low-pressure chamber; A support hub is arranged inside the lower connecting pipe. The support hub and the inner wall of the lower connecting pipe are fixed together by rib plates. The lower end of the shaft is fixed inside the support hub. Moving guide vanes are evenly distributed on the circumference of the shaft below the impeller. Both ends of the moving guide vanes are rotating shafts. One end of the rotating shaft is connected with a corresponding shaft hole on the support hub, and the other end of the rotating shaft is connected with a corresponding shaft hole on the outer wall of the stator lower end cover; A rotating ring is arranged on the outer wall of the stator lower end cover. The rotating ring is connected with the extending shaft of the moving guide vane through a connecting rod spherical bearing; The rotating ring is connected with the piston rod of the actuator. The rotation of the rotating ring is driven by the telescopic movement of the piston rod, thereby changing the opening degree of the moving guide vane. The actuator calculates and controls the opening degree of the moving guide vane according to the flow signal, the return water pressure signal or the return water temperature signal of the liquid flow through the PLC controller to realize the intelligent regulation of the operating flow of the circulating cooling water system; The cross-sectional area of the first pressure guiding pipe is more than twice the cross-sectional area of the first pressure guiding hole; the cross-sectional area of the second pressure guiding pipe is more than twice the cross-sectional area of the third pressure guiding hole.

2. A variable operating condition regulating residual pressure recovery system, characterized in that: It includes a cooling tower and a grid-connected system installed on site; cooling tower packing is arranged inside the cooling tower. A cooling tower water distributor is laid above the cooling tower packing. A fan is arranged at the top of the cooling tower. A fan speed reducer is arranged at the lower end of the fan. The fan speed reducer is connected with a fan motor on the cooling tower through a transmission shaft; the cooling tower water distributor is connected with a return water pipeline. The variable-condition regulating residual pressure recovery device described in claim 1 is installed on the vertical pipeline of the return water pipeline. The permanent magnet rotor of the residual pressure recovery device rotates under the action of the liquid flow with the impeller, and the electric energy generated in the stator winding is directly used for the fan motor through the grid-connected system installed on site; A first valve is arranged at the water inlet of the residual pressure recovery device, and a third valve is arranged at the water outlet of the residual pressure recovery device; a bypass pipeline is arranged between the water inlet and the water outlet of the residual pressure recovery device, and a second valve is arranged on the bypass pipeline; The grid-connected system is used to control the operating speed of the variable-condition regulating residual pressure recovery equipment, and to match the liquid flow angle with the impeller blade setting angle at different active guide vane openings.

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