Low-water-head water turbine with flow guide wing bionic blades

Abstract

The invention discloses a low-water-head water turbine with a flow guide wing bionic blade, which is provided with a variable pitch system for adjusting an included angle between a runner blade and an incoming flow direction, and a deflection control system for adjusting an included angle between a guide vane arranged on a bulb body and the incoming flow direction, the water flow impact acting force on the blades can be changed through the water flow impact acting force, the water flow impact acting force on the blades can be changed through the water flow impact acting force, and the water flow impact acting force on the blades can be changed through the water flow impact acting force. In addition, the blade of the runner of the hydraulic turbine set is the blade with the wave-shaped front edge, and a section protruding outwards is arranged in a pipeline for containing the bulb body and the runner, so that the water energy utilization rate of the hydraulic turbine set is further increased. The blade adopts a sine curve-shaped waveform front edge, and the structure simulates a convex shape on a fin-shaped limb of an underwater organism, so that the resistance in water is reduced, and the water energy utilization rate of a water turbine set is increased.

Description

Technical Field

[0001] The invention belongs to the technical field of bulb tubular turbines, and in particular relates to a low-head turbine with guide wing bionic blades. Background Art

[0002] Hydropower is a low-carbon, environmentally friendly green energy source. Due to its abundant hydropower resources, hydropower offers advantages over other forms of green energy, including simple site selection, high power generation, and stable output. However, traditional turbines also suffer from the drawback of requiring a high starting head, meaning they can only start when there is a significant difference in upstream and downstream water levels. This limitation limits the turbine's applicability and results in a certain amount of water energy wasted during operation. To address this issue, low-head turbines have emerged. The bulb-through turbine is the latest development in the low-head turbine field. This type of turbine features a generator enclosed in a bulb-shaped housing resembling an incandescent light bulb, with the bulb end at the front. The turbine runner is mounted at the rear socket of the bulb, with its rotating shaft coaxial with the central axis of the bulb housing. Both the bulb housing and runner are housed in a pipe, through which water flows from front to back, driving the turbine. This type of turbine has a large bulb-shaped shell at the center, so this type of unit is vividly called a bulb-shaped cross-flow turbine.

[0003] The structural characteristics of a bulb-type tubular turbine dictate a high water velocity through the pipe. However, the resistance encountered by the runner equipped with traditional blades increases significantly as the speed increases, preventing the runner from reaching high speeds. This limits the turbine's water energy utilization. Furthermore, because the water in the pipe is constantly flowing, the runner speed is difficult to adjust. If the generator fails and the electromagnetic torque output reaches zero, and the runner cannot be shut down in time, the runner speed increases rapidly, reaching the runaway speed. The runaway speed is approximately 1.7 to 2.6 times the rated speed of the turbine unit. At this speed, the rotating components of the unit are subjected to significant centrifugal forces, potentially damaging components such as the generator rotor and turbine runner. This problem reduces the operational safety of bulb-type tubular turbines. Furthermore, the high runner speed generates numerous cavitation bubbles during rotation. These bubbles explode when they strike the blades, impacting the blade assembly and causing cavitation. Therefore, improvements to bulb-type tubular turbines are necessary to improve their water energy utilization and control the runner speed.

[0004] Research has addressed the safety issues of bulb-type tubular turbines. For example, Chinese patent application number 202311515773.9, titled "Bulb-type tubular turbine unit with runaway protection," incorporates guide vanes onto a bulb-shaped housing. These vanes are distributed circumferentially around the housing and are fixed to a rotating shaft. Half of the shaft engages the guide vanes, while the other half passes through the housing and connects to a drive mechanism within the housing. To reduce the runner speed, the drive mechanism adjusts the angle between the guide vanes and the flow direction, reducing the cross-sectional area through which water can flow, thereby reducing the runner speed. While the turbine described in this invention can achieve a certain degree of runner speed control, the blades are fixed relative to the hub, making it impossible to change the angle between the blade pressure surface and the incoming flow direction. Consequently, the turbine's speed control is limited. Furthermore, this turbine fails to increase the unit's water energy utilization or reduce cavitation caused by bubbles on the runner blades. Summary of the Invention

[0005] The purpose of the present invention is to provide a bulb-through-type turbine with guide vane bionic blades. The turbine unit is equipped with guide vanes on a bulb-shaped shell, referred to as the bulb body, so that the water flow rate flowing through the turbine unit is adjustable. In addition, the blades on the turbine unit runner have been redesigned to have better drag reduction capabilities, and the runner has variable pitch capabilities. In this way, the turbine unit can have a higher water energy utilization rate and better controllability than traditional bulb-through-type turbines.

[0006] The technical solution adopted in the present invention is as follows:

[0007] The invention comprises a bulb body, a hub, blades and a generator, wherein the generator is accommodated in the bulb body and the outer shell is fixed relative to the bulb body, a plurality of blades are mounted on the hub, all of which are circumferentially distributed around the central axis of the hub, and the hub and the blades together constitute a runner of a water turbine unit; a plurality of guide vanes are mounted on the bulb body, all of which are circumferentially distributed around the central axis of the bulb body; the bulb body, the guide vanes and the runner are all accommodated in a pipeline of the water turbine unit, with the incoming flow direction being rearward, one end of the round head of the bulb body facing forward, and its position is fixed relative to the pipeline, an opening for sleeved hub is provided at the rear of the bulb body, the front half of the hub is sleeved in the bulb body, and the rear half extends from the opening of the bulb body, and there is no gap between the outer surface of the hub and the side wall of the opening of the bulb body; the hub is coaxial with the central axis of the bulb body, and the pipeline is also coaxial with the hub and the central axis of the bulb body, and the hub is connected to the generator power; the water turbine comprises a control system, and the control system comprises sensors, Controller and actuator, the sensor is connected to the controller signal, used to monitor the turbine status parameters and transmit the monitoring signal to the controller; the controller is connected to the actuator signal, the controller determines the turbine status through the received monitoring signal, and then sends a command signal to the actuator according to the status; the actuator is a first drive motor and a second drive motor, the first drive motor is used to drive the deflection control mechanism to operate, and the second drive motor is used to drive the pitch mechanism to operate; the guide vane power is connected to the deflection control mechanism, and the deflection control mechanism can change the angle between the guide vane chord and the incoming flow direction; the blade power is connected to the pitch mechanism, and the pitch mechanism can change the angle between the blade chord and the incoming flow direction; the leading edge of the blade has a tooth-like structure, and its contour conforms to the morphological characteristics of the sine function curve. The part of the leading edge of the blade protruding forward is recorded as a convex node, with the direction away from the center axis of the hub as the outside, and the convex node size is larger the farther away from the center axis of the hub.

[0008] In the prior art, the blades used in the runners of bulb-through turbines are conventional blades, and the runners lack a variable pitch function. The turbine unit of the present invention has an overall structure similar to that of conventional bulb-through turbines, but with the addition of guide vanes to block incoming flow, the redesigned runner blades, and the runner with variable pitch adjustment capability. Considering that the water level and flow rate in rivers are constantly changing, these changes in hydrological conditions will affect the flow rate of water passing through the turbine unit. The presence of guide vanes regulates the flow rate of the water in the turbine unit, keeping the generator output power as close to the rated value as possible. This increases the turbine unit's adaptability to changing hydrological conditions and prevents wear and even material failure of key components such as the blades and telescopic transmission rods. Furthermore, the leading edge shape of the turbine unit of the present invention is designed to mimic the shape of the flippers of aquatic animals such as whales and turtles. Although both are used for paddling and maintaining balance, unlike the fins of fish, the flippers of animals like whales and turtles contain bones, while fish fins do not. A fish fin is merely a thin sheet, while flippers are much thicker due to the presence of bones. Under the same conditions, flippers experience much greater resistance when moving through water. To achieve a survival advantage, flipper-equipped animals like whales and sea turtles have evolved a wavy, concave-convex structure on the leading edge of their flippers over time. This structure offers excellent drag reduction in water. Compared to a straight leading edge, a concave-convex leading edge facilitates the conformation of incoming flow to the flipper surface, reducing the vortices generated when the incoming flow separates from the surface. The turbine blades of the present invention utilize a flat surface with a wavy leading edge, minimizing the water resistance encountered by the runner during rotation. Furthermore, given that the linear velocities of the inner and outer portions of the runner blades differ during rotation, with the outer portion experiencing a much faster linear velocity, the knobs closer to the outer end are larger. Relatively speaking, among all regular shapes, knobs with a sinusoidal shape are more effective at reducing drag than other shapes. Therefore, the knobs on the leading edge of the blades of the present invention utilize a sinusoidal shape, balancing drag reduction with ease of processing. In addition, the wavy structure of the leading edge reduces the vortex generated when the incoming flow separates from the surface, and cavitation will be generated in the vortex. Therefore, the leading edge waveform reduces cavitation while reducing drag, thereby reducing the cavitation phenomenon caused by the cavitation bursting on the blade surface when it hits the blade.

[0009] Further optimization, the blade is a flat plate, and the shape of the leading edge contour is specifically as follows: the leading edge contour shape corresponds to the shape of a function curve, and the function is recorded as the leading edge function. The line connecting the innermost and outermost points of the leading edge is taken, and the total length of the line is set as X. Then the line is regarded as a range corresponding to the independent variable of the leading edge function, and the position of the innermost point of the leading edge is recorded as 0, the position of the outermost point is recorded as X, and the position of any point on the line is recorded as x, 0≤x≤X, then each position x will have a corresponding dependent variable y; assuming that the number of convex nodes on the leading edge is M, the leading edge function curve is divided into M segments, and the first M-1 segments contain a convex node and a concave node, and the concave node is the part of the leading edge that is concave backward; in the first M-1 segments, the convex nodes are all on the inside of the concave node, and the last segment has only one convex node. The connection between the two adjacent segments is the zero point, that is, the corresponding dependent variable y=0, and the connection between the convex node and the concave node in the same segment is also the zero point; the corresponding formula for the convex node curve is Where k is the stage number, k=1,2,…,M, Δk is the compensation amount, at the zero point at the beginning of each stage, there is A is the sine coefficient, which is determined by the chord length of the blade (14) corresponding to the position x; assuming that the zero point at the junction of the convex and concave nodes in each segment is x k , then the corresponding formula for the concave node is y=sin(xx k +π). This function curve shape can meet the requirements of the leading edge shape while having a simple structure. In addition, the size of the sine coefficient A is determined by the blade chord length corresponding to the position x. In this way, the convex section corresponding to the longer blade chord length protrudes forward a greater distance, which is more conducive to the drag reduction characteristics of the blade.

[0010] A further optimization involves fixedly attaching a guide vane to the suction side of the blade, the rearward-facing side. The guide vane is a flat blade, parallel to the blade and fixed relative to the blade. Projecting the guide vane onto the suction side in a direction perpendicular to the blade, the projection is close to both the trailing and outer edges of the blade. As mentioned previously, cavitation is generated in the vortex that forms when the incoming flow separates from the blade surface. Therefore, minimizing the separation of the incoming flow from the blade surface can reduce cavitation and thus alleviate cavitation. For turbine runner blades, the pressure side, or the side facing the incoming flow, is always in contact with the incoming flow. On the suction side, the incoming flow flows from the leading edge of the blade into the suction side under the negative pressure created by the blade's rotation. Due to the backward flow inertia of the incoming flow, the incoming flow does not remain in contact with the suction surface after entering it, and typically separates from the suction surface before reaching the trailing edge. In order to avoid the separation of the incoming flow from the suction surface as much as possible, the part of the suction surface close to the trailing edge and the outer edge needs to be equipped with guide vanes parallel to the blades to keep the incoming flow parallel to the blades. The installation position is close to the outer edge because the incoming flow will move outward under the action of centrifugal force.

[0011] Further optimization, the wheel hub can slide in the front and rear directions in the open opening of the bulb body; the generator is connected to the wheel hub through a telescopic transmission rod, the telescopic transmission rod includes a front half and a rear half, the rear half of which can be telescoped in the front half, the front end of the telescopic transmission rod is coaxially fixedly connected to the generator rotor, the rear half is fixed relative to the wheel hub, and the telescopic transmission rod as a whole is coaxial with the central axis of the wheel hub; a pressure sensing assembly is installed at the front end of the wheel hub, the pressure sensing assembly includes a sliding rod, a sliding sleeve, a pressure sensor and an elastic member, the elastic member is sleeved on the sliding rod, the front end of the elastic member is fixedly connected to the sliding sleeve, the rear end is fixedly connected to the pressure sensor, the rear end of the sliding rod is also fixedly connected to the pressure sensor, the front end is inserted into the sliding sleeve, the sliding sleeve is sleeved on the sliding rod and can slide on the sliding rod, the front end of the sliding sleeve is fixedly equipped with a slider, and when the front end of the sliding rod is inserted into the deepest part of the sliding sleeve, the elastic member is in a naturally extended state; the pressure sensor is the control system sensor, and multiple pressure sensing assemblies are distributed circumferentially around the telescopic transmission rod; the bulb body also accommodates a fixed disk, and the center of the fixed disk is opened There is a second transmission hole, and the fixed plate is sleeved on the front half of the telescopic transmission rod through the second mounting hole, and the relative position of the fixed plate and the bulb body is fixed; a slide is provided on the rear side of the fixed plate, the slide is annular, and the central axis of the ring is coaxial with the telescopic transmission rod. The slider is embedded in the slide and can slide in the slide. When the turbine unit is running, the slider cannot be separated from the slide; the pressure sensing assembly also includes a mounting member, the mounting member is provided with a first transmission hole, the mounting member is sleeved on the rear half of the telescopic transmission rod through the first transmission hole, and the pressure sensor is fixedly mounted on the front side of the mounting member; a mounting seat is fixedly installed in the front opening of the hub, and a third transmission hole is provided in the mounting seat for passing the telescopic transmission rod. The rear half of the telescopic transmission rod is passed through the third transmission hole, and there is no contact between the mounting seat and the telescopic transmission rod; the rear side of the mounting member is in contact with the front side of the mounting seat and is fixedly connected; a limit cover is fixedly installed on the outer edge of the hub opening, the limit cover is tubular, its central axis is coaxial with the hub, and the outer diameter of the limit cover is larger than the open diameter of the bulb body.

[0012] By monitoring the overall force exerted by the incoming flow on the turbine runner, it is possible to directly determine whether the force exerted on the runner is excessive, thereby effectively assessing the safety status of the turbine unit. Directly monitoring the overall pressure exerted on the runner is a better indicator of the turbine unit's status than monitoring the incoming flow velocity. Under the impact of the incoming flow, the runner moves backward. The fixed plate, connected through the slideway, slider, and sleeve, exerts a pulling effect on all elastic members. Although the turbine unit of the present invention includes multiple pressure sensors, these pressure sensors do not monitor individually, but instead obtain an overall force value under the pulling of the elastic members. Because the force exerted by the water flow is so strong, a single pressure sensor may not be able to measure an accurate value. Because the runner is continuously rotating under the impact of the incoming flow, the pressure sensing assembly also rotates accordingly. At this time, the turbine unit will not tilt in the direction of any pressure sensor. This principle is similar to that of a gyroscope. Therefore, the pressure detection method of the turbine unit of the present invention is accurate and reasonable.

[0013] Further optimization has been made, with the pipeline consisting of a water inlet pipe, a runner cover, and a draft tube. The order of the three parts from front to back is water inlet pipe, draft tube, and runner cover, with their central axes coaxial and adjacent parts fixedly connected. Both the water inlet pipe and the runner cover are straight pipes, and the inner diameter of the runner cover is no larger than that of the water inlet pipe. The draft tube wall is outwardly convex, and the cross-section of the wall along the circumference is an arch. This structure allows the incoming flow to reduce pressure and increase flow rate when it reaches the draft tube, before entering the runner cover housing the runner. To maintain a high flow rate, the diameter of the runner cover must be equal to or smaller than that of the water inlet pipe. This allows the incoming flow to have a greater driving effect on the runner, increasing the water energy utilization rate of the turbine unit.

[0014] Further optimization, the specific structure of the pitch mechanism is as follows: a plurality of mounting openings are opened on the hub in the circumferential direction around the central axis, the number of the mounting openings is the same as the number of blades, a base is correspondingly installed in each mounting opening, and the base and the mounting opening are assembled through bearings; a limit plate is fixedly installed on the outer surface of the base, the inner surface of the limit plate is in contact with the base and at the same time in contact with the outer surface of the hub, a mounting frame is fixedly installed on the outer surface, and the blades are fixedly installed on the limit plate through the mounting frame; a connecting rod is fixedly connected to the inner side of the base, the connecting rod is a straight rod and is perpendicular to the inner side of the base; a connecting hole is opened at one end of the connecting arm, and a hinged seat is installed at the other end, the central axis of the connecting hole is perpendicular to the length direction of the connecting arm, and the connecting rod is not perpendicular to the inner side of the base One end of the base connection is passed through the connecting hole, the surface of the connecting rod fits the hole wall and the connecting rod can rotate and slide in the connecting hole; the wheel hub also accommodates an adjustment seat, and a plurality of connecting rods are fixedly installed on the adjusting seat, one end of the connecting rod is connected to the adjusting seat, and the other end is fixedly installed with a connecting head. The number of connecting rods is the same as the number of blades, and all connecting rods are circumferentially distributed around the adjusting seat, and the connecting head is hinged to the articulated seat, and the bottom of the articulated seat is rotatably connected to the end face of the connecting arm; an adjustment hole is opened in the center of the adjusting seat, and the wheel hub also accommodates a second drive motor, the relative position of the second drive motor housing and the wheel hub is fixed, and the rotor of the second drive motor is inserted in the adjustment hole and fixedly connected to the adjustment seat.

[0015] When the angles between the blades and the incoming flow direction are different, the incoming flow forces on the blades are also different. When the incoming flow velocity is high, in order to prevent the turbine unit from being damaged due to the excessively fast rotation speed of the runner, the blades need to have the ability to adjust the pitch. In the turbine unit of the present invention, the angle and orientation adjustment of all blades are achieved synchronously through the rotation of the adjustment seat, which not only reduces the complexity of the pitch system, but also ensures that the angles and orientations of all blades are consistent, avoiding the failure of the pitch system to cause different blade angles and orientations, thereby causing uneven centrifugal force on the runner and causing damage to parts in the turbine unit. The limit plate fixedly installed on the outer surface of the base is to facilitate the installation of the blades and prevent the base from being inserted too shallowly or too deeply into the installation opening.

[0016] Further optimization, the specific structure of the deflection control mechanism is as follows: the guide vane is a flat plate, each guide vane is provided with a mounting hole, the central axis of the mounting hole is parallel to the surface of the guide vane, each guide vane is fixedly connected to a guide vane shaft, and the outer half of the guide vane shaft is embedded in the mounting hole; a plurality of through-holes are provided on the bulb body, the inner half of the guide vane shaft passes through the through-holes and is inserted into the bulb body, all the guide vane shafts are circumferentially distributed around the central axis of the bulb body, and the through-holes correspond one-to-one to the guide vanes and the guide vane shafts; the bulb body accommodates a driving shaft and a fixed shaft, the front end of the fixed shaft is fixedly connected to the inner surface of the bulb body, and the rear end is sleeved in the center hole of the second bevel gear and the second bevel gear can be relatively The fixed shaft rotates with the rear end of the drive shaft coaxially fixedly connected to the rotor of the first drive motor. The first drive motor is housed within the bulb body, and the first drive motor housing is fixedly mounted relative to the bulb body. The front end of the drive shaft is sleeved within the center hole of the second bevel gear and fixedly connected to the second bevel gear. The center axes of the drive shaft and the fixed shaft are both coaxial with the center axis of the bulb body. The fixed shaft has a receiving hole corresponding to the guide vane shaft, and the inner end of the guide vane shaft is inserted into the receiving hole and can rotate relative to the receiving hole. The first bevel gear is sleeved on the inner half of each guide vane shaft. The first bevel gear and the guide vane shaft are fixed relative to each other, and all first bevel gears mesh with the second bevel gear. Like the pitch control mechanism, the deflection control mechanism also has the advantage of ensuring the consistent angular position of all guide vanes and synchronized adjustment of the angular position of all guide vanes. To simplify the control system, no sensor is used to monitor the angular position of the guide vanes. The deflection control mechanism adopts open-loop control. Each time the controller issues a command to the deflection control mechanism, it records the angular position of the guide vanes after the command is executed.

[0017] Further optimization is required, with the control system sensors including a flow rate sensor, an angle sensor, a pressure sensor, a speed meter, and a power meter. The flow rate sensor is fixedly mounted on the outer surface of the hub, in front of the base. The angle sensor is fixedly mounted on the mounting bracket. The speed meter and power meter are fixedly mounted within the bulb body, respectively monitoring the generator's rotor speed and output power. All sensors transmit corresponding monitoring data to the controller in real time. The control system prevents component damage when the incoming flow rate is too high and increases the overall efficiency of the turbine unit when the incoming flow rate is low, allowing the turbine unit of the present invention to continuously maintain optimal operating conditions.

[0018] For further optimization, each mounting frame is fixed with an angle sensor, and each angle sensor corresponds to a unique serial number. All angle sensors are connected to the controller signal and transmit monitoring data to the controller at the same time. If there is inconsistency in the monitoring data of multiple angle sensors at the same time, the controller will determine that the turbine unit has failed and mark the blade corresponding to the monitoring data and other inconsistent angle sensors as a faulty blade. As mentioned above, when the angle position of a blade in the runner is different from that of other blades, the runner will be eccentric due to uneven force on the blade, and the components in the turbine unit may be damaged or accelerate aging and wear. In order to avoid such situations, each blade in the runner must have a corresponding angle sensor to monitor its angle position. When a blade has a problem, the control system will immediately issue a warning reminder, so that the operator can promptly detect abnormalities in the operating status of the turbine unit.

[0019] The beneficial effects of the method of the present invention are:

[0020] 1. The turbine unit of the present invention uses blades with corrugated leading edges and an outwardly protruding section is provided in the pipe that accommodates the bulb body and the runner, thereby increasing the water energy utilization rate of the turbine unit;

[0021] 2. The turbine unit is equipped with a variable pitch mechanism, which enables the angle between the blades and the incoming flow direction to be adjusted, making the turbine unit more adaptable to hydrological conditions;

[0022] 3. The turbine unit is equipped with a deflection control mechanism, which enables the angle between the guide vane and the incoming flow direction to be adjusted. When the incoming flow velocity is high, it can resist the incoming flow to avoid damage to the turbine unit, thereby increasing the safety of the turbine unit.

[0023] 4. The existence of the control system enables the turbine unit of the present invention to have higher power generation efficiency when the incoming flow velocity is slow, and plays a protective role for the device when the incoming flow velocity is fast, thereby having more superior overall performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the overall structure of the water turbine unit of the present invention when the guide vanes are fully closed;

[0025] Figure 2 A schematic diagram of the overall structure of the water turbine unit of the present invention when the guide vanes are fully opened;

[0026] Figure 3 Overall schematic diagram of the guide vane deflection control mechanism;

[0027] Figure 4 Schematic diagram of the blade shape in the runner of a water turbine unit;

[0028] Figure 5 Overall schematic diagram of the blade pitch mechanism in the turbine runner;

[0029] Figure 6 Schematic diagram of the combined structure of the turbine runner and pressure sensor assembly;

[0030] Figure 7 Schematic diagram of the exploded structure of the turbine runner and pressure sensor assembly;

[0031] Figure 8 Schematic diagram of the overall structure of the pressure sensing component. DETAILED DESCRIPTION

[0032] To make the purpose, technical solution, and advantages of the method of the present invention more clear, the technical solution of the present invention will be clearly and completely described below through specific embodiments. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0033] Example 1:

[0034] A low-head turbine with biomimetic guide vane blades comprises a bulb body 1, an inlet pipe 2, a runner cover 3, a guide pipe 4, guide vanes 5, a hub 10, and a generator 20. The generator 20 is housed within the bulb body 1, its housing fixedly connected to the bulb body 1. Six blades 14 are circumferentially distributed around the central axis of the impeller hub 10. The hub 10 and blades 14 together constitute the turbine runner. The inlet pipe 2, the runner cover 3, and the guide pipe 4 together form a pipeline that accommodates the bulb body 1 and the runner. With the incoming flow directed rearward, the pipeline comprises, from front to back, the inlet pipe 2, the guide pipe 4, and the runner cover 3. The central axes of the three sections are coaxial, and adjacent sections are fixedly connected. The water inlet pipe 2 and the rotor housing 3 are straight tubes of equal diameter, with the direction closest to the central axis of the bulb body 1 as the inner direction. The flow guide pipe 4 is a rotating body with an outwardly convex tube wall. The cross-section along the circumference of the tube wall is an arcuate shape. Six guide vanes 5 are distributed circumferentially around the central axis of the bulb body 1. The bulb body 1 has a rounded end facing forward. The position of the bulb body 1 relative to the pipe is secured by two crossbars. One end of each crossbar is fixedly connected to the outer surface of the bulb body 1 and the other end is fixedly connected to the inner wall of the water inlet pipe 2. The rear of the bulb body 1 has an opening for the hub 10. The front half of the hub 10 fits within the bulb body 1, while the rear half extends out of the opening. The front end of the hub 10 also has an opening. The hub 10 is coaxial with the central axis of the bulb body 1, and the pipe is also coaxial with the hub 10 and the central axis of the bulb body 1. There is no gap between the outer surface of the hub 10 and the side wall of the opening of the bulb body 1, and the hub 10 can slide forward and backward within the opening. The overall appearance and structure of the turbine unit is as follows Figure 1 and Figure 2 shown.

[0035] exist Figure 1In the figure, the guide vanes 5 are flat blades of uniform thickness, shaped like an isosceles trapezoid, with the shorter base of the trapezoid on the inside. Each guide vane 5 has a mounting hole. The central axis of the mounting hole lies on the symmetry plane of the guide vane 5 and is parallel to the line connecting the upper and lower bases of the isosceles trapezoid. The mounting hole passes through the guide vane 5, and each guide vane 5 is fixedly connected to a guide vane shaft 6. The outer half of the guide vane shaft 6 is inserted into the mounting hole. The bulb body 1 has six through-holes, through which the inner half of the guide vane shaft 6 is inserted into the bulb body 1. All guide vane shafts 6 are circumferentially distributed around the central axis of the bulb body 1 and all guide vane shafts 6 are located in the same plane. The bulb body 1 contains a driving shaft 9 and a fixed shaft 60. The central axes of the driving shaft 9 and the fixed shaft 60 are both coaxial with the central axis of the bulb body 1. The front end of the fixed shaft 60 is fixedly connected to the inner surface of the bulb body 1, and the rear end is inserted into the central hole of the second bevel gear 8, and the second bevel gear 8 can rotate relative to the fixed shaft 60. The rear end of the driving shaft 9 is fixed and coaxially connected to the rotor of the first driving motor. The first driving motor is a stepping motor, which is housed in the bulb body 1 and the outer shell is fixedly connected to the bulb body 1. The front end of the driving shaft 9 is inserted into the central hole of the second bevel gear 8 and fixedly connected to the second bevel gear 8. Six receiving holes corresponding to the guide vane shaft 6 are provided on the fixed shaft 60. The inner end of the guide vane shaft 6 is inserted into the receiving holes, and the guide vane shaft 6 can rotate relative to the receiving holes. The first bevel gear 7 is sleeved on the inner half of all the guide vane shafts 6. The relative position of the first bevel gear 7 and the guide vane shaft 6 is fixed, and all the first bevel gears 7 are engaged with the second bevel gear 8. The deflection control mechanism of the guide vane 5 is as shown in the figure. Figure 3 shown.

[0036] The blade 14 is also a flat blade with uniform thickness. Its leading edge is a tooth-like structure, the trailing edge contour is a straight line, and the outer edge contour is an outwardly convex arc. The chord length of the blade 14 gradually increases from the inside to the outside. The leading edge contour shape conforms to the shape characteristics of the sine function curve, specifically: the leading edge contour shape corresponds to the shape of a certain function curve, and the function is recorded as the leading edge function. A line is taken between the innermost and outermost points of the leading edge, and the total length of the line is set as X. The line is then regarded as a range corresponding to the leading edge function independent variable, and the position of the innermost point of the leading edge is recorded as 0, the position of the outermost point is recorded as X, and the position of any point on the line is recorded as x, 0≤x≤X, then each position x will have a corresponding dependent variable y; assuming that the number of convex nodes on the leading edge is M, the leading edge function curve is divided into M segments, and the first M-1 segments contain a convex node and a concave node, and the concave node is the part of the leading edge that is concave backward; in the first M-1 segments, the convex nodes are all on the inside of the concave node, and the last segment has only one convex node. The connection between the two adjacent segments is the zero point, that is, the corresponding dependent variable y=0, and the connection between the convex node and the concave node in the same segment is also the zero point; the corresponding formula for the convex node curve is Where k is the stage number, k=1,2,…,M, Δk is the compensation amount, at the zero point at the beginning of each stage, there is A is the sine coefficient, which is determined by the chord length of the blade (14) corresponding to the position x; assuming that the zero point at the junction of the convex and concave nodes in each segment is x k , then the corresponding formula for the concave node is y=sin(xx k +π). In this embodiment, the leading edge function has a total of six segments, and the size of A is 0.1 times the chord length of the blade corresponding to the x position. A mounting rod is welded on the suction surface of the blade 14, that is, the side facing away from the incoming flow direction. One end of the mounting rod is connected to the blade 14, and the other end is welded to the guide wing 141. The guide wing 141 is a flat blade with a shape that is narrow inside and wide outside. The outer edge is an arc convex outward, and the other three edges are straight lines. The outer edge curve of the guide wing 141 is the same as the outer edge curve of the blade 14. A guide wing 141 is welded on each blade 14, and the guide wing 141 is distributed parallel to the blade 14, so that the guide wing 141 is projected on the suction surface in a direction perpendicular to the suction surface of the blade 14, and the projection is close to the trailing edge and outer edge of the blade 14 at the same time.

[0037] The hub 10 has six mounting openings circumferentially around the central axis, each housing a corresponding base 12. Base 12 and the mounting openings are assembled via bearings. The outer side of base 12 is fixedly connected to a limit plate 11. Limit plate 11 is circular and has a diameter larger than that of base 12. The inner surface of limit plate 11 is connected to base 12 and contacts the outer surface of hub 10. A mounting bracket 13 is fixedly mounted on the outer surface of limit plate 11, coaxial with the central axis of base 12. In this embodiment, mounting bracket 13 comprises two parallel flat plates perpendicular to the outer surface of limit plate 11. The inner ends of blades 14 are clamped between these two plates and connected to the plates. An angle sensor 19 is fixedly mounted on the plates. A connecting rod 102 is fixedly connected to the inner side of base 12. Connecting rod 102 is a straight rod perpendicular to the inner side of base 12. The connecting arm 101 has a connecting hole at one end and a hinged seat at the other end. The bottom of the hinged seat is rotatably connected to the end of the connecting arm 101. The central axis of the connecting hole is perpendicular to the length of the connecting arm 101. The connecting rod 102 is inserted into the connecting hole and can slide and rotate in the connecting hole. The wheel hub 10 also accommodates an adjustment seat 100. In this embodiment, the main body of the adjustment seat 100 is a regular hexagonal disc. Six connecting rods are fixedly connected to the adjustment seat 100. One end of the connecting rod is connected to the corner of the regular hexagon, and the other end is fixedly equipped with a connecting head. The connecting rods are circumferentially distributed around the axis of the adjustment seat 100, and the length direction of the connecting rod is parallel to the extension direction of the edge of the regular hexagon. The connecting head is hinged to the hinged seat. The center of the adjustment seat 100 has an adjustment hole. The wheel hub 10 also accommodates a second drive motor. The housing of the second drive motor is fixedly connected to the wheel hub 10, and the rotor of the second drive motor is inserted into the adjustment hole and fixedly connected to the adjustment seat 100. The above structure is a pitch mechanism for controlling the pitch of blades 14. The overall schematic diagram of the pitch mechanism is as follows: Figure 5 shown.

[0038] The wheel hub 10 transmits power to the generator 20 via a telescopic transmission rod 21. The telescopic transmission rod 21 includes a front half and a rear half, with the rear half being retractable within the front half. The front end of the telescopic transmission rod 21 is coaxially fixedly connected to the rotor of the generator 20, and the rear end is fixedly connected to the wheel hub 10, with its central axis coaxial with the central axis of the wheel hub 10. A pressure sensing assembly 16 is mounted at the front end of the wheel hub 10. The pressure sensing assembly 16 comprises a slide rod 160, a sleeve 161, a pressure sensor 162, and an elastic member 163. In this embodiment, the elastic member 163 is a spring, which is sleeved on the slide rod 160. The front end of the spring is fixedly connected to the sleeve 161, and the rear end is fixedly connected to the pressure sensor 162. The rear end of the slide rod 160 is fixedly connected to the pressure sensor 162. The front end of the spring is inserted into the sleeve 161. The sleeve 161 can slide along the slide rod 160, but the slide rod 160 cannot pass through the sleeve 161. When the slide rod 160 is inserted into the sleeve 161 at its deepest point, the spring is in a naturally extended state. A slider 1610 is fixedly mounted on the front end of the sleeve 161. A fixed disk 17 is mounted on the front half of the telescopic transmission rod 21. A second transmission hole is defined in the center of the fixed disk 17. The fixed disk 17 is coaxial with the central axis of the telescopic transmission rod 21. A slideway 170 is defined on the rear side of the fixed disk 17. The slideway 170 is annular, with its central axis coaxial with the fixed disk 17. The slider 1610 can slide in the slideway 170 and cannot be disengaged from the slideway 170 when the turbine unit is in operation. The pressure sensing assembly 16 also includes a mounting member. In this embodiment, the mounting member is a mounting disk with a first transmission hole defined in the center of the mounting disk. The mounting disk is coaxial with the telescopic transmission rod 21 and is mounted on the rear half of the telescopic transmission rod 21 through the first transmission hole. A pressure sensor 162 is fixedly mounted on the front side of the mounting disk. In this embodiment, there are six pressure sensors 162, all of which are circumferentially distributed around the central axis of the mounting disk. A mounting seat 103 is fixedly mounted in the front opening of the hub 10. The rear side of the mounting plate is in contact with and fixedly connected to the front side of the mounting seat 103. In this embodiment, the mounting seat 103 is disc-shaped, with a third transmission hole in the center for passing the telescopic transmission rod 21. The edge is fixedly connected to the hub 10, and there is no contact between the mounting seat 103 and the telescopic transmission rod 21. A limit cover 164 is fixedly mounted on the outer edge of the hub 10 opening. The limit cover 164 is tubular, and its central axis is coaxial with the hub 10. The outer diameter of the limit cover 164 is larger than the open diameter of the bulb body 1. The distribution of the turbine runner and the pressure sensor assembly 16 is shown in the figure. Figure 6 and Figure 7 As shown, the overall structure diagram of the pressure sensing component 16 is as shown in Figure 8 shown.

[0039] When there is no incoming flow in the turbine pipeline, the hub 10 is in its original position, and the elastic member 163 is in a naturally stretched state. When there is incoming flow in the pipeline, the incoming flow impacts the turbine runner, exerting pressure on the runner. Under this impact, the runner moves backward, and the hub 10 slides backward relative to its original position. At this time, the fixed plate 17 and the slideway 170 remain stationary, while the mounting plate, the mounting seat 103, the slide rod 160, and the pressure sensor 162 move backward synchronously with the hub 10. Because the hub 10 rotates under the impact of the incoming flow, the aforementioned components also rotate synchronously with the hub 10. The sleeve 161 and the slider 1610 also rotate synchronously with the hub 10 but do not move backward. As a result, the elastic member 163 is stretched and exerts an elastic force. The pressure sensor 162 monitors the elastic force in the elastic member 163. When the impact force of the incoming flow decreases, the hub 10 will gradually move closer to the original position under the action of the elastic member 163 , and the limiting cover 164 can prevent the hub 10 from escaping from the opening of the bulb body 1 .

[0040] The hydraulic turbine unit of the present invention has a control system comprising a flow rate sensor 18, an angle sensor 19, a pressure sensor 162, a rotational speed meter, a power meter, and a controller. The flow rate sensor 18 is fixedly mounted on the outer surface of the hub 10 and positioned in front of the blades 14. The flow rate sensor 18, angle sensor 19, and pressure sensor 162 are all signal-connected to the controller. The three controllers transmit three physical quantities, namely, the flow rate on the hub 10 surface, the orientation angle of the blades 14, and the water pressure acting on the runner, in the form of signals in real time to the controller. The rotational speed meter and power meter are used to monitor the rotational speed and output power of the generator 20, respectively. Both the rotational speed meter and the power meter are signal-connected to the controller and transmit the rotational speed and output power of the generator 20 in real time to the controller in the form of signals. The system also includes a first drive motor and a second drive motor. The controller is connected to the two drive motors by signals. During the operation of the turbine unit, the controller will combine the above five signals to make a judgment on the current operating status of the turbine unit, and send command signals to the first drive motor and the second drive motor based on the judgment results to adjust the status of the guide vanes 5 and the blades 14, and record the azimuth angle of the guide vanes 5 after adjustment. When the output power of the generator 20 is lower than the rated power, the controller will send a signal to rotate the guide vanes 5 to a position parallel to the incoming flow direction, and the blades 14 to a position where the force of the incoming flow is the largest. When the output power of the generator 20 is higher than the rated power, the controller will send a signal to rotate the guide vanes 5 to a position perpendicular to the incoming flow direction, and the blades 14 to a position parallel to the incoming flow direction. When the guide vane 5 is in a position parallel to the incoming flow direction, it is in a fully open position, and when it is in a position perpendicular to the incoming flow direction, it is in a fully closed position. The states of the fully open position and the fully closed position are as follows: Figure 2 and Figure 1 shown.

[0041] Example 2:

[0042] In this embodiment, there are six mounting brackets 13, each equipped with an angle sensor 19. Each angle sensor 19 is assigned a unique serial number and is connected to a controller signal, transmitting the azimuth angle of the corresponding blade 14 to the controller in real time. If the azimuth angle data uploaded by any of the six angle sensors 19 is inconsistent with the others, the controller will indicate a turbine runner fault and the serial number of the faulty blade 14. The remainder of this embodiment is consistent with that described in Example 1.

[0043] It is understandable that the number of the guide vanes 5 and blades 14 may be other than six.

[0044] It is understandable that the flow guide tube 4 may also be a straight tube.

[0045] It is understandable that the bulb body 1 can also be fixed to the position of the turbine unit pipe in other ways.

[0046] It is understandable that the water turbine unit may not have the pressure sensing component 16, or the pressure sensing component 16 may also be in the form of other structures.

[0047] It is understandable that the guide vane 5 may also be of other shapes, and the mechanism for adjusting the azimuth angle of the guide vane 5 may also be of other structural forms.

[0048] It is understandable that the mounting bracket 13 may also be in other forms as long as it can fix the blade 14 relative to the limiting plate 11 .

[0049] It is understandable that the sine coefficient A may also have other values.

[0050] It is understandable that the blade 14 may not have the guide wing 141 .

[0051] It is understood that the control system may include more sensors, or fewer sensors, as well as other types of sensors.

Claims

1. A low-head turbine with bionic guide vane blades, characterized by: The invention comprises a bulb body (1), a hub (10), blades (14) and a generator (20), wherein the generator (20) is accommodated in the bulb body (1) and the outer shell is fixed relative to the bulb body (1); a plurality of blades (14) are mounted on the hub (10), all of which are circumferentially distributed around the central axis of the hub (10); the hub (10) and the blades (14) together constitute a turbine runner; a plurality of guide vanes (5) are mounted on the bulb body (1), all of which are circumferentially distributed around the central axis of the bulb body (1); the bulb body (1), the guide vanes (5) and the runner are all accommodated In the pipeline of the water turbine unit, the incoming flow is backward, one end of the bulb body (1) is forward, and its position is fixed relative to the pipeline. The rear part of the bulb body (1) is provided with an opening for sleeve-mounting a hub (10). The front half of the hub (10) is sleeved in the bulb body (1), and the rear half extends out of the opening of the bulb body (1). There is no gap between the outer surface of the hub (10) and the side wall of the opening of the bulb body (1); the hub (10) is coaxial with the central axis of the bulb body (1), and the pipeline is also coaxial with the central axis of the hub (10) and the bulb body (1). The hub (10) is connected to the generator (20) in a power connection. The turbine comprises a control system, which comprises a sensor, a controller and an actuator. The sensor is connected to the controller signal and is used to monitor the turbine state parameters and transmit the monitoring signal to the controller. The controller is connected to the actuator signal and determines the turbine state through the received monitoring signal and then sends a command signal to the actuator according to the state. The actuator comprises a first drive motor and a second drive motor, the first drive motor is used to drive the deflection control mechanism to operate, and the second drive motor is used to drive the pitch mechanism to operate. The guide vane (5) is connected to the deflection control mechanism by power, and the deflection control mechanism can change the angle between the chord line of the guide vane (5) and the incoming flow direction. The blade (14) is connected to the pitch mechanism by power, and the pitch mechanism can change the angle between the chord line of the blade (14) and the incoming flow direction. The leading edge of the blade (14) is a tooth-like structure, and its contour conforms to the morphological characteristics of a sine function curve. The portion of the leading edge of the blade (14) protruding forward is recorded as a convex node. With the direction away from the central axis of the hub (10) as the outside, the convex node size is larger the further outward the distribution position is.

2. A low-head turbine with guide vane bionic blades according to claim 1, characterized in that: The blade (14) is a flat plate, and the shape of its leading edge profile is specifically as follows: the leading edge profile shape corresponds to the shape of a function curve, and the function is recorded as the leading edge function. A line is taken between the innermost and outermost points of the leading edge, and the total length of the line is set as X. The line is then regarded as a range corresponding to the leading edge function independent variable, and the position of the innermost point of the leading edge is recorded as 0, the position of the outermost point is recorded as X, and the position of any point on the line is recorded as x, 0≤x≤X, then each position x will have a corresponding dependent variable y; assuming that the number of convex nodes on the leading edge is M, the leading edge function curve is divided into M segments, and the first M-1 segments each contain a convex node and a concave node, and the concave node is the part of the leading edge that is concave backward; in the first M-1 segments, the convex nodes are all on the inner side of the concave node, and the last segment has only one convex node. The connection point of the two adjacent segments is zero, that is, the corresponding dependent variable y=0, and the connection point of the convex node and the concave node in the same segment is also zero; the corresponding formula of the convex node curve is Where k is the stage number, k=1,2,…,M, Δk is the compensation amount, at the zero point at the beginning of each stage, there is A is the sine coefficient, which is determined by the chord length of the blade (14) corresponding to the position x; assuming that the zero point at the junction of the convex and concave nodes in each segment is x k , then the corresponding formula for the concave node is y=sin(xx k +π).

3. A low-head turbine with guide vane bionic blades according to claim 2, characterized in that: A guide wing (141) is fixedly connected to the suction surface of the blade (14), that is, the rearward side. The guide wing (141) is a flat blade, distributed parallel to the blade (14) and fixed relative to the blade (14). When the guide wing (141) is projected onto the suction surface in a direction perpendicular to the suction surface of the blade (14), the projection is located at a position close to both the trailing edge and the outer edge of the blade (14).

4. A low-head turbine with guide vane bionic blades according to claim 3, characterized in that: The hub (10) can slide in the front-back direction in the opening of the bulb body (1); the generator (20) is connected to the hub (10) through a telescopic transmission rod (21); the telescopic transmission rod (21) includes a front half and a rear half, and the rear half can be telescoped in the front half. The front end of the telescopic transmission rod (21) is coaxially fixedly connected to the rotor of the generator (20), and the relative position of the rear half and the hub (10) is fixed. The telescopic transmission rod (21) is coaxial with the central axis of the hub (10); a pressure sensing component (16) is installed at the front end of the hub (10), and the pressure sensing component (16) includes a sliding rod (160), a sliding sleeve (161), a pressure sensor (162) and an elastic member (163), and the elastic member (163) is sleeved. On the slide rod (160), the front end of the elastic member (163) is fixedly connected to the slide sleeve (161), and the rear end is fixedly connected to the pressure sensor (162). The rear end of the slide rod (160) is also fixedly connected to the pressure sensor (162). The front end is inserted into the slide sleeve (161). The slide sleeve (161) is sleeved on the slide rod (160) and can slide on the slide rod (160). A slider (1610) is fixedly installed at the front end of the slide sleeve (161). When the front end of the slide rod (160) is inserted into the deepest part of the slide sleeve (161), the elastic member (163) is in a naturally extended state. The pressure sensor (162) is the control system sensor. A plurality of pressure sensing components (16) are circumferentially distributed around the telescopic transmission rod (21). The bulb body (1) further houses a fixed disk (17), a second transmission hole is provided at the center of the fixed disk (17), the fixed disk (17) is sleeved on the front half of the telescopic transmission rod (21) through the second mounting hole, and the fixed disk (17) and the bulb body (1) are fixed in relative position; a slideway (170) is provided on the rear side surface of the fixed disk (17), the slideway (170) is annular, and the central axis of the ring is coaxial with the telescopic transmission rod (21), and a slider (1610) is embedded in the slideway (170) and can slide in the slideway (170), and the slider (1610) cannot be separated from the slideway (170) when the turbine unit is running; the pressure sensor assembly (16) also includes a mounting member, a first transmission hole is provided on the mounting member, and the mounting member is mounted through the first transmission hole. The hole sleeve is arranged on the rear half of the telescopic transmission rod (21), and the pressure sensor (162) is fixedly mounted on the front side of the mounting piece; a mounting seat (103) is fixedly mounted in the front opening of the wheel hub (10), a third transmission hole for passing the telescopic transmission rod (21) is opened in the mounting seat (103), the rear half of the telescopic transmission rod (21) is passed through the third transmission hole, and there is no contact between the mounting seat (103) and the telescopic transmission rod (21); the rear side of the mounting piece is fitted with and fixedly connected to the front side of the mounting seat (103); a limiting cover (164) is fixedly mounted on the outer edge of the opening of the wheel hub (10), the limiting cover (164) is tubular, the central axis of which is coaxial with the wheel hub (10), and the outer diameter of the limiting cover (164) is larger than the open diameter of the bulb body (1).

5. A low-head turbine with guide vane bionic blades as claimed in claim 4, characterized in that: The pipeline is composed of three parts: a water inlet pipe (2), a rotor cover (3), and a flow guide pipe (4). The three parts are arranged in the order of the water inlet pipe (2), the flow guide pipe (4), and the rotor cover (3) from front to back. The central axes of the three parts are coaxial, and any two adjacent parts are fixedly connected. The water inlet pipe (2) and the rotor cover (3) are both straight pipes, and the inner diameter of the rotor cover (3) is not larger than the inner diameter of the water inlet pipe (2). The wall of the flow guide pipe (4) is convex outward, and the cross-sectional shape of the wall along the circumferential direction is arc-shaped.

6. A low-head turbine with guide vane bionic blades as claimed in claim 5, characterized in that: The specific structure of the pitch mechanism is as follows: a plurality of mounting openings are provided on the hub (10) in a circumferential direction around the central axis, the number of the mounting openings being the same as the number of the blades (14), a base (12) being correspondingly provided in each mounting opening, and the base (12) and the mounting opening being assembled through a bearing; a limiting plate (11) is fixedly provided on the outer surface of the base (12), the inner surface of the limiting plate (11) is in contact with the base (12) and the outer surface of the hub (10), a mounting frame (13) is fixedly provided on the outer surface, and the blades (14) are fixedly provided on the limiting plate (11) through the mounting frame (13); a connecting rod (102) is fixedly provided on the inner side surface of the base (12), the connecting rod (102) is a straight rod and is perpendicular to the inner side surface of the base (12), and the central axis of the connecting rod (102) does not coincide with the central axis of the base (12); a connecting hole is provided at one end of the connecting arm (101), and a hinge seat is provided at the other end The end of the connecting rod (102) that is not connected to the base (12) is passed through the connecting hole, and the connecting rod (102) can rotate and slide in the connecting hole; the wheel hub (10) also accommodates an adjustment seat (100), and a plurality of connecting rods are fixedly installed on the adjustment seat (100), and the number of the connecting rods is the same as the number of the blades (14). One end of the connecting rod is fixedly connected to the adjustment seat (100), and the other end is fixedly installed with a connecting head, and the number of the connecting rods is the same as the number of the blades (14). All the connecting rods are circumferentially distributed around the adjustment seat (100), and the connecting head is hinged to the hinge seat, and the bottom of the hinge seat is rotatably connected to the end face of the connecting arm (101); an adjustment hole is opened in the center of the adjustment seat (100), the second drive motor is accommodated in the wheel hub (10), and the relative position of the motor housing and the wheel hub (10) is fixed, and the rotor of the second drive motor is inserted into the adjustment hole and fixedly connected to the adjustment seat (100).

7. A low-head turbine with guide vane bionic blades as claimed in claim 6, characterized in that: The specific structure of the deflection control mechanism is as follows: the guide vane (5) is a flat plate, each guide vane (5) is provided with a mounting hole, the central axis of the mounting hole is parallel to the surface of the guide vane (5), each guide vane (5) is fixedly connected to a guide vane shaft (6), and the outer half of the guide vane shaft (6) is embedded in the mounting hole; a plurality of through holes are provided on the bulb body (1), the inner half of the guide vane shaft (6) passes through the through holes and is inserted into the bulb body (1), all the guide vane shafts (6) are circumferentially distributed around the central axis of the bulb body (1), and the through holes correspond to the guide vanes (5) and the guide vane shafts (6) one by one; the bulb body (1) contains a driving shaft (9) and a fixed shaft (60), the front end of the fixed shaft (60) is fixedly connected to the inner surface of the bulb body (1), and the rear end is sleeved in the central hole of the second bevel gear (8), and the second bevel gear (8) can be relatively The fixed shaft (60) rotates, and the rear end of the driving shaft (9) is coaxially fixedly connected to the rotor of the first driving motor. The first driving motor is accommodated in the bulb body (1) and the motor housing is fixedly installed relative to the bulb body (1). The front end of the driving shaft (9) is sleeved in the center hole of the second bevel gear (8) and is fixedly connected to the second bevel gear (8). The center axes of the driving shaft (9) and the fixed shaft (60) are coaxial with the center axis of the bulb body (1). The fixed shaft (60) is provided with a receiving hole corresponding to the guide vane shaft (6). The inner end of the guide vane shaft (6) is inserted into the receiving hole and the guide vane shaft (6) can rotate relative to the receiving hole. The inner half sections of all the guide vane shafts (6) are sleeved with the first bevel gear (7), the first bevel gear (7) is fixedly connected to the guide vane shaft (6), and all the first bevel gears (7) are meshed with the second bevel gear (8).

8. A low-head turbine with guide vane bionic blades as claimed in claim 7, characterized in that: The control system sensors include a flow rate sensor (18), an angle sensor (19), a pressure sensor (162), a rotation speed meter and a power meter, wherein the flow rate sensor (18) is fixedly mounted on the outer surface of the hub (10), and the flow rate sensor (18) is located in front of the base (12), the angle sensor (19) is fixedly mounted on the mounting frame (13), and the rotation speed meter and the power meter are fixedly mounted in the bulb body (1), and are respectively used to monitor the rotor speed and output power of the generator (20); all sensors transmit corresponding monitoring data to the controller in real time.

9. A low-head turbine with guide vane bionic blades as claimed in claim 8, characterized in that: An angle sensor (19) is fixedly mounted on each mounting frame (13), and each angle sensor (19) corresponds to a unique serial number. All angle sensors (19) are connected to the controller signal and simultaneously transmit monitoring data to the controller. If the monitoring data of multiple angle sensors (19) at the same time are inconsistent, the controller will determine that a fault has occurred in the turbine unit and mark the blade (14) corresponding to the angle sensor (19) whose monitoring data is inconsistent with that of other inconsistent angle sensors as a faulty blade.

Images