Wireless sensor node energy collection device based on underground wind energy and use method

Abstract

The invention discloses a wireless sensor node energy collecting device based on underground wind energy. The wireless sensor node energy collecting device comprises a bottom plate, an upstream rotating magnetic force collecting module, a downstream wind-induced vibration energy collecting module, a controller, a battery and a power management circuit. The downstream wind-induced vibration energy collecting module is arranged at a lower air port of the upstream rotating magnetic force collecting module, and wind passes through the upstream rotating magnetic force collecting module and then passes through the downstream wind-induced vibration energy collecting module; when wind passes through the upstream rotary magnetic force collecting module, an upstream interference cylinder is driven to rotate, and a piezoelectric vibrator is excited to vibrate through a magnet block and an excitation magnet block so as to absorb wind energy; when wind passes through the downstream wind-induced vibration energy collection module, the vibration of the downstream cylinder drives the second piezoelectric vibrator to vibrate so as to absorb wind energy. The upstream rotating magnetic force collecting module and the downstream wind-induced vibration energy collecting module are provided, and efficient collection of wind energy in the environment is achieved through mixed use of the two modules.

Description

Technical Field

[0001] The invention relates to the technical field of environmental energy collection, and in particular to a wireless sensor node energy collection device based on underground wind energy and a method of using the device. Background Art

[0002] In order to achieve real-time dynamic monitoring of underground coal mine personnel, equipment, operating environment, etc., and ensure safe production in coal mines, underground coal mine monitoring and surveillance systems have emerged. However, the underground environment of coal mines is complex and changeable. The traditional wired monitoring method has problems such as difficult wiring and cables being easily corroded by the underground environment, and it is no longer sustainable. Wireless sensor networks have the characteristics of flexible deployment and self-power supply, and have been widely used in the status monitoring of electromechanical equipment in coal mines. However, due to the large scale of underground wireless sensor nodes and the harsh service environment, it is difficult for underground workers to replace the batteries of the nodes in time, making it impossible for wireless sensor nodes to achieve long-term monitoring. Therefore, it is necessary to study energy harvesting technology that is suitable for the service condition characteristics of wireless sensor nodes for underground coal mine status monitoring to extend the life of the nodes.

[0003] Environmental energy harvesting technology is a technology that converts available energy in the environment into electrical energy, which can solve the problem of limited node energy. For nodes, they work in the underground area of ​​coal mines. The "Coal Mine Safety Regulations" stipulates the ventilation standards for this area, and the wind speed is 0.25-4m / s. Therefore, piezoelectric vibrators can be used to convert the wind energy in the node service environment into electrical energy to achieve node energy replenishment and further extend the life of the node.

[0004] However, although there is stable wind energy in the service environment of coal mine underground equipment status monitoring nodes, the wind speed is relatively small (v≤4m / s). The existing method of collecting single wind energy based on the principle of wind-induced vibration has the problem of low energy collection efficiency, and it is difficult to effectively collect low-speed wind energy in the node service environment. Summary of the invention

[0005] In view of the deficiencies in the prior art, the present invention provides a wireless sensor node energy collection device based on underground wind energy and a method of use to solve the technical problem that the prior art cannot efficiently collect wind energy in coal mines.

[0006] The present invention provides a wireless sensor node energy collection device based on downhole wind energy, comprising: a bottom plate, an upstream rotating magnetic force collection module, a battery and a power management circuit; the upstream rotating magnetic force collection module comprises: a rotating shaft fixing bracket, a wind blade, an upstream interference cylinder, a piezoelectric vibrator, a piezoelectric vibrator fixing bracket, a rotating shaft, a magnet block and an excitation magnet block;

[0007] Two rotating shaft fixing brackets are vertically arranged on the bottom plate; the rotating shaft penetrates into the upstream interference cylinder along the axis of the upstream interference cylinder, and both ends of the rotating shaft are mounted on the rotating shaft fixing brackets; the fan blades are arranged at both ends of the rotating shaft, and the rotating shaft is driven to rotate with the wind; the piezoelectric vibrator fixing bracket is vertically arranged on the bottom plate below the upstream interference cylinder; the piezoelectric vibrator is fixed on the piezoelectric vibrator fixing bracket at one end in the form of a cantilever beam, and the output end of the piezoelectric vibrator is connected to the power management circuit; the magnet block is fixed on the side of the suspended end of the piezoelectric vibrator facing the upstream interference cylinder; the excitation magnet block is fixed on the surface of the upstream interference cylinder, corresponding to the position of the magnet block, and rotates with the upstream interference cylinder to periodically magnetically excite the magnet mass block; the output of the power management circuit is respectively connected to the battery and the wireless sensor node.

[0008] Furthermore, the entire piezoelectric vibrator moves up and down along the height direction on the piezoelectric vibrator fixing bracket, and the magnetic moment between the magnet block and the excitation magnet block is adjusted by adjusting the height of the piezoelectric vibrator on the piezoelectric vibrator fixing bracket.

[0009] Furthermore, the wireless sensor node energy collection device based on downhole wind energy also includes: a frequency adjustment component; the frequency adjustment component includes: a mobile control unit and a limiting block, the mobile control unit is fixed on the piezoelectric vibrator fixing bracket, the piezoelectric vibrator passes through the limiting block, and the mobile control unit pushes the limiting block to move back and forth along the extension direction of the piezoelectric vibrator, and the position of the limiting block on the piezoelectric vibrator is the clamping end of the piezoelectric vibrator.

[0010] Furthermore, the wireless sensor node energy collection device based on downhole wind energy also includes: a downstream wind-induced vibration energy collection module; the downstream wind-induced vibration energy collection module is arranged at the downwind position of the upstream rotating magnetic collection module, and the wind first passes through the upstream rotating magnetic collection module and then passes through the downstream wind-induced vibration energy collection module;

[0011] The downstream wind-induced vibration energy collection module includes: a second piezoelectric vibrator, a second piezoelectric vibrator fixing bracket and a downstream cylinder; the second piezoelectric vibrator fixing bracket is vertically arranged on the bottom plate; the second piezoelectric vibrator is fixed on the second piezoelectric vibrator fixing bracket at one end in the form of a cantilever beam, and the output end of the second piezoelectric vibrator is connected to the power management circuit; one end of the downstream cylinder is fixedly connected to the suspended end of the second piezoelectric vibrator, and the downstream cylinder is arranged relative to the upstream interference cylinder in parallel with its axis and at the same height.

[0012] Furthermore, the second piezoelectric vibrator fixing bracket can move on the bottom plate to adjust the distance between the downstream cylinder and the upstream interference cylinder.

[0013] Furthermore, the wireless sensor node energy collection device based on downhole wind energy also includes: a second frequency adjustment component; the second frequency adjustment component includes: a second mobile control unit and a second limiting block, the second mobile control unit is fixed on the second piezoelectric vibrator fixing bracket, the second piezoelectric vibrator passes through the limiting block, and the second mobile control unit pushes the second limiting block to move back and forth along the extension direction of the second piezoelectric vibrator, and the position of the second limiting block on the second piezoelectric vibrator is the clamping end of the second piezoelectric vibrator.

[0014] Furthermore, the magnetic moment between the magnet block and the excitation magnet block ranges from 10 mm to 15 mm, and the smaller the wind speed, the larger the magnetic moment between the magnet block and the excitation magnet block.

[0015] The present invention also provides a method for using a wireless sensor node energy collection device based on underground wind energy, comprising:

[0016] The device is placed in a coal mine, so that the axial heights of the upstream interference cylinder and the downstream cylinder are at half the height of the coal mine, the upstream interference cylinder is on the windward side, and the downstream cylinder is on the leeward side;

[0017] According to the wind speed in the coal mine, the height of the piezoelectric vibrator is adjusted to adjust the magnetic moment between the magnet block and the exciting magnet block.

[0018] Furthermore, the method for using the wireless sensor node energy collection device based on underground wind energy also includes: adjusting the position of the limit block on the piezoelectric vibrator according to the wind speed in the coal mine to adjust the vibration frequency of the piezoelectric vibrator, and / or adjusting the position of the second limit block on the second piezoelectric vibrator to adjust the vibration frequency of the second piezoelectric vibrator.

[0019] Beneficial effects of the present invention:

[0020] The present invention proposes an upstream rotating magnetic force collection module and a downstream wind-induced vibration energy collection module, and the two modules are used in combination to realize efficient collection of wind energy in the environment; the upstream rotating magnetic force collection module triggers energy collection through the rotational motion of a rotatable component, thereby obtaining a periodic piezoelectric signal, and at the same time, when the fluid flows around the upstream interference cylinder, an alternating wake vortex is generated to interfere with the downstream cylinder, thereby affecting the dynamic response of the downstream cylinder, and further affecting the power generation performance of the piezoelectric vibrator. At the same time, when the downstream cylinder meets certain conditions, it will also undergo vortex-induced vibration under the action of the fluid, thereby causing the piezoelectric vibrator to deform and generate electrical energy, thereby solving the problems of low energy collection efficiency and short life of sensor nodes brought about by the traditional single wind energy collection method;

[0021] The present invention establishes the positional relationship of the optimal aspect ratio and the size relationship of the optimal diameter ratio between the upstream rotating magnetic force collection module and the downstream wind-induced vibration energy collection module, and on this basis, selects a reasonable magnetic moment to maximize energy collection.

[0022] When the wind speed changes, the present invention can, on the one hand, change the natural frequency of the piezoelectric vibrator by adjusting the position of the limiting block on the piezoelectric vibrator so that it matches the ambient frequency and maximizes energy collection; on the other hand, the height of the piezoelectric vibrator can be adjusted to adjust the distance between the magnet mass block and the excitation magnet to ensure the rotational motion of the rotatable component, so as to further improve the energy collection efficiency of the upstream rotating magnetic collection module; BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The features and advantages of the present invention will be more clearly understood by referring to the accompanying drawings, which are schematic and should not be construed as limiting the present invention in any way. In the accompanying drawings:

[0024] Figure 1 is a stereoscopic view of a specific embodiment of the present invention;

[0025] Figure 2 It is a front view of a specific embodiment of the present invention;

[0026] Figure 3 is a schematic diagram of the overall structure of the upstream rotating magnetic collection module in a specific embodiment of the present invention;

[0027] Figure 4 is a schematic diagram of the overall structure of a downstream wind-induced vibration energy collection module in a specific embodiment of the present invention;

[0028] Figure 5 is a schematic structural diagram of a piezoelectric vibrator fixing bracket in a specific embodiment of the present invention;

[0029] Figure 6 is a schematic structural diagram of a second piezoelectric vibrator fixing bracket in a specific embodiment of the present invention;

[0030] Figure 7 is a structural schematic diagram of a bearing seat fixing bracket in a specific embodiment of the present invention;

[0031] Figure 8 is a schematic diagram of a simulated flow field in a specific embodiment of the present invention;

[0032] Fig. 9 is a schematic diagram of the power generation voltage under the first group of different aspect ratios in a specific embodiment of the present invention;

[0033] Fig.10 is a schematic diagram of power generation voltage under the second group of different aspect ratios in a specific embodiment of the present invention;

[0034] Fig.11 is a schematic diagram of power generation voltage under different diameter ratios in a specific embodiment of the present invention;

[0035] Fig.12 It is a schematic diagram of the power generation voltage of the piezoelectric vibrator under different magnetic moments in a specific embodiment of the present invention. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means a limitation on the present invention and its application or use. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Unless otherwise specified, the relative arrangement, expressions and numerical values ​​of the components and steps described in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and devices known to ordinary technicians in the relevant fields may not be discussed in detail, but where appropriate, the techniques, methods and devices should be regarded as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values.

[0037] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations).

[0038] like Figure 1 , 2As shown, the present invention provides a wireless sensor node energy collection device based on downhole wind energy, comprising: a bottom plate 1, an upstream rotating magnetic force collection module 3, a downstream wind-induced vibration energy collection module 2, a controller, a battery and a power management circuit; the downstream wind-induced vibration energy collection module 2 is arranged at the downwind position of the upstream rotating magnetic force collection module 3, and the wind first passes through the upstream rotating magnetic force collection module 3 and then passes through the downstream wind-induced vibration energy collection module 2;

[0039] like Figure 3 As shown, the upstream rotating magnetic force collection module 3 includes: a bottom plate 1, a rotating shaft 310 fixing bracket 38, a fan blade 39, an upstream interference cylinder 31, a piezoelectric vibrator 33, a piezoelectric vibrator fixing bracket 32, a rotating shaft 310, a magnet block 34 and an excitation magnet block 35;

[0040] like Figure 7 As shown, two rotating shafts 310 fixing brackets 38 are vertically arranged on the bottom plate 1; the rotating shaft 310 penetrates the upstream interference cylinder 31 along the axis of the upstream interference cylinder 31, and both ends of the rotating shaft 310 are mounted on the rotating shaft 310 fixing brackets 38; the fan blade 39 is a spoon-shaped fan blade 39, which can be 3 blades or 8 blades. The fan blade 39 is arranged at both ends of the rotating shaft 310 through a rubber ring, and the rotating shaft 310 is driven to rotate with the wind to collect wind energy; the piezoelectric vibrator fixing bracket 32 ​​is vertically arranged on the bottom plate 1 below the upstream interference cylinder 31; the piezoelectric vibrator 33 One end of the piezoelectric vibrator is fixed on the piezoelectric vibrator fixing bracket 32 ​​in the form of a cantilever beam, and the output end of the piezoelectric vibrator 33 is connected to the power management circuit; the magnet block 34 is fixed on the side of the suspended end of the piezoelectric vibrator 33 facing the upstream interference cylinder 31; the excitation magnet block 35 is fixed on the surface of the upstream interference cylinder 31, corresponding to the position of the magnet block 34, and rotates with the upstream interference cylinder 31 to periodically magnetically excite the magnet mass block, so that the piezoelectric vibrator 33 produces vibration displacement, thereby converting vibration energy into electrical energy; the output of the power management circuit is respectively connected to the battery and the wireless sensor node.

[0041] like Fig.12 As shown in the figure, the change of the power generation voltage of the piezoelectric vibrator 33 at different magnetic moments, when the magnetic moment decreases from 15mm to 5mm, the amplitude of the power generation voltage increases. This is mainly because when the magnetic moment decreases, the force between the magnets increases. However, due to the low wind speed in the node service environment (v≤4m / s), the too small magnetic moment (d≤5mm) will make the force between the magnets too large, resulting in the system not having enough energy to cross the potential barrier. In this case, the rotation of the spoon-shaped blades is no longer stable, thereby greatly reducing the power generation performance. Therefore, in actual application, it is necessary to adjust the magnetic moment to avoid the reduction of energy collection efficiency due to too small magnetic moment.

[0042] like Figure 5As shown, the piezoelectric vibrator fixing bracket 32 ​​includes: a support frame 321, a motor 313, a screw rod 36, and a piezoelectric vibrator fixing frame 311; the screw rod 36 is vertically arranged, and one end is connected to the output shaft of the motor 313, the piezoelectric vibrator fixing frame 311 moves up and down on the screw rod 1206, and one end of the piezoelectric vibrator 33 is fixed to the upper edge of the piezoelectric vibrator fixing frame 311. The up and down movement of the piezoelectric vibrator fixing frame 311 can change the height of the piezoelectric vibrator 33;

[0043] The frequency adjustment component includes: a mobile control unit and a limiting block 37. The mobile control unit includes: a motor 314, a screw rod 312, and a nut 315. The motor 314 is arranged in the frame of the piezoelectric vibrator fixing frame 311 and moves up and down with the piezoelectric vibrator fixing frame 311; the screw rod 312 is parallel to the extension direction of the piezoelectric vibrator 33, and one end is connected to the motor 314; the nut 315 is screwed on the screw rod 312; the limiting block 37 is fixedly connected to the nut 315; the piezoelectric vibrator 33 passes through the limiting block 37, and the motor 314 rotates the screw rod 312 to push the limiting block 37 connected to the nut 315 to move back and forth along the extension direction of the piezoelectric vibrator 33. The position of the limiting block 37 on the piezoelectric vibrator 33 is the clamping end of the piezoelectric vibrator 33.

[0044] like Figure 4 As shown, the downstream wind-induced vibration energy collection module 2 includes: a second piezoelectric vibrator 22, a second piezoelectric vibrator fixing bracket 23 and a downstream cylinder 21; the second piezoelectric vibrator fixing bracket 23 is vertically arranged on the base plate 1; the second piezoelectric vibrator 22 is fixed at one end to the upper edge of the second piezoelectric vibrator fixing bracket 23 in the form of a cantilever beam, and the output end of the second piezoelectric vibrator 22 is connected to the power management circuit; one end of the downstream cylinder 21 is fixedly connected to the suspended end of the second piezoelectric vibrator 22, and the downstream cylinder 21 and the upstream interference cylinder 31 are arranged parallel to the axis and at the same height relative to each other.

[0045] like Figure 6 As shown, the second frequency adjustment component includes: a second mobile control unit and a limiting block 25, the second mobile control unit includes: a motor 24, a screw rod 26, and a nut 27, the motor 24 is arranged in the second piezoelectric vibrator fixing bracket 23; the screw rod 26 is parallel to the extension direction of the second piezoelectric vibrator 22, and one end is connected to the motor 24; the nut 27 is screwed on the screw rod 26; the limiting block 25 is fixedly connected to the nut 27; the second piezoelectric vibrator 22 passes through the limiting block 25, and the motor 24 rotates the screw rod 26 to push the limiting block 25 connected to the nut 27 to move back and forth along the extension direction of the second piezoelectric vibrator 22, and the position of the limiting block 25 on the second piezoelectric vibrator 22 is the clamping end of the second piezoelectric vibrator 22.

[0046] like Figure 8As shown, it is assumed that the distances between the upstream interference cylinder 31 and the downstream cylinder 21 and the upper and lower boundaries of the fluid domain are both W / 2, and the diameters of the two cylinders are D1 and D2 respectively; the width of the fluid domain is W, and the inlet and outlet are set on the left and right sides respectively. The distances between the upstream interference cylinder 31 and the inlet and the downstream cylinder 21 are set to D and L respectively, where L and D2 are variables, L / D1 is defined as the aspect ratio, and D2 / D1 is defined as the diameter ratio. Obviously, the aspect ratio and the diameter ratio will affect the aerodynamic characteristics around the downstream cylinder 21, and the vibration characteristics of the cylinder under the wake induced effect can be changed by changing the above two variables.

[0047] like Fig. 9 , 10 As shown in the figure, at the same wind speed, the power generation voltage changes under 8 different aspect ratios L / D1. It can be seen that as the aspect ratio L / D1 increases, the power generation voltage first rises slowly, then suddenly increases, and finally decreases, and all show vortex-induced vibration characteristics. This shows that the aspect ratio has a significant impact on the power generation performance, and there is an optimal aspect ratio that makes the overall power generation voltage of the piezoelectric vibrator 33 reach the maximum.

[0048] like Fig.11 As shown in FIG. 1 , under the same wind speed and the best aspect ratio, the effect of different diameter ratios D2 / D1 on the power generation performance of the wind-induced vibration piezoelectric vibrator 33 with an interference cylinder is shown. It can be seen that as the diameter ratio continues to decrease, the power generation voltage of the piezoelectric vibrator 33 shows an overall downward trend. Therefore, in actual application, it is necessary to select a suitable diameter ratio to improve the power generation efficiency.

[0049] In general, when the wind energy flows around the spoon-shaped blade 39 and the upstream interference cylinder 31, on the one hand, the spoon-shaped blade 39 will rotate, thereby driving the upstream interference cylinder 31 on the rotating shaft 310 to rotate synchronously. At this time, the excitation magnet block 35 on the upstream interference cylinder 31 will periodically excite the piezoelectric vibrator 33 with the magnet block 34 fixed at the free end, thereby generating electrical energy; on the other hand, considering that wind-induced vibration is a fluid-solid coupling process of mutual conversion between fluid kinetic energy and vibration energy, that is, when a stable fluid encounters an obstacle during movement, under certain conditions, an alternating vortex will be formed at the tail of the obstacle, and a pressure difference will be generated, thereby forming a periodic resistance, namely the Karman vortex street effect. Therefore, when the fluid flows around the upstream interference cylinder 31, an alternating wake vortex will be generated to interfere with the downstream cylinder 21, thereby affecting the dynamic response of the downstream cylinder 21, and further affecting the power generation performance of the piezoelectric vibrator 33. At the same time, when certain conditions are met, the downstream cylinder 21 itself will also undergo vortex-induced vibration under the action of the fluid, thereby causing the second piezoelectric vibrator 22 to deform and generate electrical energy.

[0050] The present invention also provides a method for using a wireless sensor node energy collection device based on underground wind energy, comprising:

[0051] The device is placed in a coal mine, so that the axial heights of the upstream interference cylinder and the downstream cylinder are at half the height of the coal mine, the upstream interference cylinder is on the windward side, and the downstream cylinder is on the leeward side;

[0052] According to the wind speed in the coal mine, the height of the piezoelectric vibrator is adjusted to adjust the magnetic moment between the magnet block and the exciting magnet block;

[0053] The vibration frequency of the piezoelectric vibrator can also be adjusted by adjusting the position of the limit block on the piezoelectric vibrator according to the wind speed in the coal mine, and / or adjusting the position of the second limit block on the second piezoelectric vibrator to adjust the vibration frequency of the second piezoelectric vibrator.

[0054] The motor and the lead screw can be used to adjust the magnetic moment and the fixed end distance to adapt to the change of wind speed. Since the wind speed in coal mines in different areas is different, the wind speed in coal mines in the same area is relatively stable for a long time, that is, the wind speed in coal mines has the characteristics of regional discreteness and time stability, so the motor and the lead screw do not need to be used frequently. Once properly adjusted according to the local wind speed, the device can maintain stable performance for a long time, thereby reducing maintenance frequency and cost, and improving the reliability and efficiency of the system.

[0055] Before implementing adaptive regulation according to the wind speed in a coal mine, it is necessary to establish a collection of piezoelectric vibrators with optimal power generation performance:

[0056] For the upstream piezoelectric vibrator, it is necessary to establish a relationship model between different wind speeds, different magnetic moments and different fixed distances:

[0057] (1) According to the wind speed range of different scenes in the mine, establish a wind speed set: V 风速 =[v1,v2,…v n ];

[0058] (2) Through experiments, different magnetic moments d 磁矩 =[d1,d2,…d n ] corresponds to the minimum starting wind speed V 最小风速 =[v min1 ,v min2 ,…v minn ], establish different magnetic moments and minimum starting wind speed sets: [d1, d2, …d n ]→[v min1 ,v min2 ,…v minn ];

[0059] (3) When the natural frequency of the piezoelectric vibrator is consistent with or close to the excitation frequency, the power generation performance of the piezoelectric vibrator is the greatest; based on this, it is necessary to obtain the power generation performance of the piezoelectric vibrator at different wind speeds V through experiments. 风速 =[v1,v2,…v n ] corresponds to the optimal fixed distance L of the piezoelectric vibrator = [L1, L2, ... L n ], establish the optimal fixed distance of the piezoelectric vibrator and the current wind speed set: [L1,L2,…L n ]→[v1,v2,…v n ];

[0060] For the downstream piezoelectric vibrator, it is necessary to establish a relationship model between different wind speeds and different fixed distances:

[0061] (1) According to the wind speed range of different scenes in the mine, establish a wind speed set: V 风速 =[v1,v2,…v n ];

[0062] (2) When the natural frequency of the piezoelectric vibrator is consistent with or close to the excitation frequency, the power generation performance of the piezoelectric vibrator is the greatest; based on this, it is necessary to obtain the power generation performance of the piezoelectric vibrator at different wind speeds V through experiments. 风速 =[v1,v2,…v n ] corresponds to the optimal fixed distance S of the piezoelectric vibrator = [S1, S2, ... S n ], establish the optimal fixed distance of piezoelectric vibrator 2 and the current wind speed set: [S1, S2, … S n ]→[v1,v2,…v n ];

[0063] The specific process of adaptive adjustment is as follows:

[0064] Step A1: According to the collected voltage, the ambient wind speed v and the excitation frequency f are obtained. The specific implementation steps are as follows:

[0065] Step A11: using the comparator of the microprocessor to convert the simple sine wave voltage generated by the piezoelectric vibrator into a square wave voltage;

[0066] Step A12: Detect the high and low pulse periods of the square wave voltage within a unit time;

[0067] Step A13: Derived from the calculated pulse period, the frequency of the excitation force on the piezoelectric vibrator is derived, and then the wind speed of the current surrounding environment is obtained;

[0068] Step A2: Adaptively adjust the magnetic moment and natural frequency of the upstream piezoelectric vibrator. The specific implementation steps are as follows:

[0069] Step A21: Adjust the magnetic moment of the piezoelectric vibrator: According to the wind speed obtained by the voltage signal, the optimal magnetic moment is obtained by looking up the corresponding table in the above-established relationship model. If the current magnetic moment is within the reasonable range of the optimal magnetic moment, no adjustment is required; if the current magnetic moment is outside the reasonable range of the optimal magnetic moment, it is necessary to use a motor and a lead screw to adjust the magnetic moment of the piezoelectric vibrator in the height direction until it reaches the optimal state;

[0070] Step A22: Adjust the natural frequency of the piezoelectric vibrator: According to the frequency of the excitation force on the piezoelectric vibrator obtained by the voltage, the optimal fixed distance is obtained by looking up the corresponding table in the above established relationship model. If the current fixed distance is within the reasonable range of the optimal fixed distance, no adjustment is required; if the current fixed distance is outside the reasonable range of the optimal fixed distance, it is necessary to use the motor and the lead screw to adjust the fixed position of the limit block on the piezoelectric vibrator in the horizontal direction;

[0071] Step A23: adaptively adjust the natural frequency of the downstream piezoelectric vibrator. The specific implementation steps are as follows:

[0072] According to the frequency of the excitation force on the piezoelectric vibrator obtained according to the voltage, the optimal fixed distance is obtained by looking up the corresponding table in the relationship model established above. If the current fixed distance is within the reasonable range of the optimal fixed distance, no adjustment is required; if the current fixed distance is outside the reasonable range of the optimal fixed distance, it is necessary to use a motor and a screw to adjust the fixed position of the limiting block on the piezoelectric vibrator in the horizontal direction.

[0073] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A wireless sensor node energy collection device based on underground wind energy, characterized in that: include: baseplate, upstream rotating magnetic collection module, battery, and power management circuitry; The upstream rotating magnetic force collection module includes: a rotating shaft fixing bracket, a fan blade, an upstream interference cylinder, a piezoelectric vibrator, a piezoelectric vibrator fixing bracket, a rotating shaft, a magnet block and an excitation magnet block; Two rotating shaft fixing brackets are vertically arranged on the bottom plate; the rotating shaft penetrates the upstream interference cylinder along the axis of the upstream interference cylinder, and both ends of the rotating shaft are mounted on the rotating shaft fixing brackets; the fan blades are arranged at both ends of the rotating shaft, and the rotating shaft is driven to rotate with the wind; the piezoelectric vibrator fixing bracket is vertically arranged on the bottom plate below the upstream interference cylinder; one end of the piezoelectric vibrator is fixed on the piezoelectric vibrator fixing bracket in the form of a cantilever beam, and the output end of the piezoelectric vibrator is connected to the power management circuit; The magnet block is fixed on the side of the suspended end of the piezoelectric vibrator facing the upstream interference cylinder; the excitation magnet block is fixed on the surface of the upstream interference cylinder, corresponding to the position of the magnet block, and rotates with the upstream interference cylinder to periodically magnetically excite the magnet mass block; the output of the power management circuit is respectively connected to the battery and the wireless sensor node.

2. The wireless sensor node energy collection device based on underground wind energy according to claim 1, characterized in that: The entire piezoelectric vibrator moves up and down along the height direction on the piezoelectric vibrator fixing bracket, and the magnetic moment between the magnet block and the excitation magnet block is adjusted by adjusting the height of the piezoelectric vibrator on the piezoelectric vibrator fixing bracket.

3. The wireless sensor node energy collection device based on underground wind energy according to claim 1 or 2, characterized in that: Also includes: Frequency regulation components; The frequency adjustment component includes: a mobile control unit and a limiting block. The mobile control unit is fixed on the piezoelectric vibrator fixing bracket. The piezoelectric vibrator passes through the limiting block. The mobile control unit pushes the limiting block to move back and forth along the extension direction of the piezoelectric vibrator. The position of the limiting block on the piezoelectric vibrator is the clamping end of the piezoelectric vibrator.

4. The wireless sensor node energy collection device based on underground wind energy as claimed in claim 1, characterized in that: Also includes: Downstream wind-induced vibration energy collection module; The downstream wind-induced vibration energy collection module is arranged at the downwind position of the upstream rotating magnetic collection module, and the wind first passes through the upstream rotating magnetic collection module and then passes through the downstream wind-induced vibration energy collection module; The downstream wind-induced vibration energy collection module includes: a second piezoelectric vibrator, a second piezoelectric vibrator fixing bracket and a downstream cylinder; the second piezoelectric vibrator fixing bracket is vertically arranged on the bottom plate; the second piezoelectric vibrator is fixed on the second piezoelectric vibrator fixing bracket at one end in the form of a cantilever beam, and the output end of the second piezoelectric vibrator is connected to the power management circuit; one end of the downstream cylinder is fixedly connected to the suspended end of the second piezoelectric vibrator, and the downstream cylinder is arranged relative to the upstream interference cylinder in parallel with its axis and at the same height.

5. The wireless sensor node energy collection device based on underground wind energy as claimed in claim 4, characterized in that: The second piezoelectric vibrator fixing bracket can move on the bottom plate to adjust the distance between the downstream cylinder and the upstream interference cylinder.

6. The wireless sensor node energy collection device based on underground wind energy as claimed in claim 4 or 5, characterized in that: Also includes: a second frequency adjustment component; The second frequency adjustment component includes: a second movable control unit and a second limiting block. The second movable control unit is fixed on the second piezoelectric vibrator fixing bracket. The second piezoelectric vibrator passes through the limiting block. The second movable control unit pushes the second limiting block to move back and forth along the extension direction of the second piezoelectric vibrator. The position of the second limiting block on the second piezoelectric vibrator is the clamping end of the second piezoelectric vibrator.

7. The wireless sensor node energy collection device based on underground wind energy according to claim 1 or 2, characterized in that: The magnetic moment between the magnet block and the exciting magnet block ranges from 10 mm to 15 mm. The smaller the wind speed, the larger the magnetic moment between the magnet block and the exciting magnet block.

8. A method for using a wireless sensor node energy collection device based on downhole wind energy, applicable to the wireless sensor node energy collection device based on downhole wind energy as claimed in any one of claims 1 to 7, characterized in that: The method comprises: The device is placed in a coal mine, so that the axial heights of the upstream interference cylinder and the downstream cylinder are at half the height of the coal mine, the upstream interference cylinder is on the windward side, and the downstream cylinder is on the leeward side; According to the wind speed in the coal mine, the height of the piezoelectric vibrator is adjusted to adjust the magnetic moment between the magnet block and the exciting magnet block.

9. The method for using the wireless sensor node energy collection device based on underground wind energy as claimed in claim 8, characterized in that: Also includes: According to the wind speed in the coal mine, the position of the limit block on the piezoelectric vibrator is adjusted to adjust the vibration frequency of the piezoelectric vibrator, and / or the position of the second limit block on the second piezoelectric vibrator is adjusted to adjust the vibration frequency of the second piezoelectric vibrator.

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