Passive wireless wind speed sensor based on flexible inductance structureTechnical Field
The invention relates to a passive wireless wind speed sensor.
Background
The internet of things is developing rapidly, and sensors are an important ring of the internet of things. Typically, the sensor nodes are battery powered and wired, which prevents deployment in inaccessible or hard-to-reach places, frequent battery replacement also increases maintenance costs, and the battery and wiring increase area, which is not conducive to high energy efficiency and high density distribution. Passive wireless sensors are capable of continuous real-time detection, require remote sensor power, and occupy a smaller amount of space in certain harsh and sealed environments where it is difficult to establish a wired connection.
Wind speed sensors have been widely used for decades, and various wind sensors using different principles have been widely studied so far based on Micro Electro Mechanical Systems (MEMS) technology. As the equipment for measuring the wind speed, the wind speed sensor is small and exquisite and light in appearance, convenient to carry and assemble, and capable of conveniently and effectively obtaining wind speed information. The water-based paint is mainly used in the fields of meteorology, agriculture, ships, industry, environmental protection and the like, and is required to be used outdoors for a long time.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the prior art, the passive wireless wind speed sensor based on the flexible inductance structure is provided, and the problem that the existing wind speed sensor cannot meet the miniaturization of the Internet of things technology due to the fact that batteries and wiring are needed is solved.
The technical scheme is as follows: a passive wireless wind speed sensor based on a flexible inductance structure comprises a reading end and a sensor end; the sensor end comprises a first planar spiral inductor and a second planar spiral inductor; the first planar spiral inductor is a flexible planar spiral inductor and is fixed on the surface of a flexible substrate deformed by wind; the substrate where the second planar spiral inductor is located is not deformed when being windy, and the first planar spiral inductor and the second planar spiral inductor form a series loop; the reading end comprises a third plane spiral inductor, the third plane spiral inductor and the second plane spiral inductor keep near magnetic field coupling, and the output end of the third plane spiral inductor is connected with the LCR tester.
The flexible substrate is attached to one surface of the wind tunnel support plate, the top of the flexible substrate extends to the outer side of the end part of the wind tunnel support plate, and the plane center of the first plane spiral inductor is opposite to the end part of the wind tunnel support plate; the third planar spiral inductor is fixed on the other surface of the wind tunnel support plate and is arranged opposite to the second planar spiral inductor.
Furthermore, the first planar spiral inductor and the second planar spiral inductor are both arranged on the same surface of the flexible substrate, a plurality of through holes are formed in the flexible substrate, and the first planar spiral inductor and the second planar spiral inductor are connected in series through a lead which penetrates through the through holes and is located on the other surface of the substrate.
Has the advantages that: (1) according to the invention, the wind speed sensor is realized by taking the flexible inductance structure as a sensor sensitive element, and the flexible inductance with the characteristic of deformation instantaneity is applied to the wind speed sensor, so that the wind speed sensor can monitor wind speed data in real time.
(2) The invention realizes wind speed detection by utilizing the mutual inductance circuit principle, realizes wireless transmission of energy between a reading end and a sensor end, and has no power supply inside the sensor end. The wind speed sensor is miniaturized, low in cost and high in energy efficiency.
(3) The wind speed detection is realized by utilizing the mutual inductance circuit principle, the wireless transmission of data quantity between the reading end and the sensor end is realized, and the reading end is connected with the sensor end through a wireless circuit. So that the wind speed sensor can be applied to harsh and sealed environments where line connections cannot be established.
Drawings
FIG. 1 is a schematic structural diagram of a passive wireless wind speed sensor based on a flexible inductive structure;
FIG. 2 is a schematic diagram of a sensor end structure of a passive wireless wind speed sensor based on a flexible inductive structure;
FIG. 3 is a schematic view of a reading end structure of a passive wireless wind speed sensor based on a flexible inductive structure;
FIG. 4 is a schematic side view of a passive wireless wind speed sensor based on a flexible inductive structure when not exposed to wind;
FIG. 5 is a schematic side view of a passive wireless wind speed sensor based on a flexible inductance structure when the sensor is exposed to wind;
fig. 6 is a schematic diagram of the principle of the mutual inductance circuit of the passive wireless wind speed sensor based on the flexible inductance structure.
Detailed Description
The invention is further explained below with reference to the drawings.
As shown in fig. 1 to 6, a passive wireless wind speed sensor based on a flexible inductive structure includes a reading end, a sensor end, and a windtunnel support plate 8. The sensor terminal comprises a first planarspiral inductor 3, a second planarspiral inductor 2, and aflexible substrate 4. Theflexible substrate 4 is rectangular, and the first planarspiral inductor 3 and the second planarspiral inductor 2 are located on the front surface of theflexible substrate 4 and located at the upper half part and the lower half part respectively. A plurality of throughholes 7 are formed in theflexible substrate 4, and the first planarspiral inductor 3 and the second planarspiral inductor 2 are connected in series through alead 5 which penetrates through the throughholes 7 and is positioned on the reverse side of the substrate to form a loop. Theflexible substrate 4 is partially attached to one surface of the windtunnel support plate 8, and the plane center of the first planarspiral inductor 3 is over against the end position of the windtunnel support plate 8 and serves as a sensitive element to deform when being affected by wind. The substrate where the second planarspiral inductor 2 is located is supported by the windtunnel support plate 8, and does not deform when being subjected to wind.
The reading end comprises a third planarspiral inductor 1, and the third planarspiral inductor 1 is fixed on the other surface of the windtunnel support plate 8 and is opposite to the second planarspiral inductor 2. The third planarspiral inductor 1 and the second planarspiral inductor 2 keep near magnetic field coupling so as to realize wireless transmission of energy and data between the reading end and the sensor end, no power supply is arranged in the sensor end, and the two ends are connected in a wireless way. The output end of the third planarspiral inductor 1 is connected with the LCR tester.
The detection method of the speed sensor comprises the following steps:
the side structures of the wind speed sensor are shown in fig. 4 and 5 when no wind exists or wind exists; the third planarspiral inductor 1 and the second planarspiral inductor 4 on the lower half part of the sensor end are fixed through the windtunnel support plate 8, a certain distance is reserved between the third planarspiral inductor 1 and the second planarspiral inductor 4, the relative position is kept unchanged, a sensor end sensitive element, namely a flexible inductor structure, is vertically faced to the wind direction, the lower half part of the first planarspiral inductor 3 is supported and fixed through the windtunnel support plate 8, when the flexible substrate is bent by wind, the projection area of the inductor on the plane can be reduced, and therefore the inductance value is reduced. When wind blows over the sensor, the equivalent inductance change of theport 6 of the reading end is detected through the LCR tester, as shown in fig. 6, the coupling inductance structure in the circuit is equivalent to a T-shaped structure according to a mutual inductance circuit formula, and the inductance change of the flexible inductance L3 at the sensor end is reversely pushed through the equivalent inductance of the port ab measured through the LCR tester to measure the wind speed.
Compared with the traditional MEMS wind speed sensor, the sensing element of the passive wireless wind speed sensor based on the flexible inductance structure is made of flexible materials, so that the real-time monitoring of wind speed data is realized; the energy and data of the reading end and the sensor end are transmitted wirelessly, no power supply is arranged in the sensor end, and the reading end is connected with the sensor end through a wireless circuit. The wind speed sensor is miniaturized, low in cost, high in energy efficiency and suitable for harsh and sealed environments where line connection cannot be established.
The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and decorations can be made without departing from the principle of the present invention, and these modifications and decorations should also be regarded as the protection scope of the present invention.