Radio frequency identification (RFID)-based wireless passive temperature measurement system and wind power gear box system

Abstract

The invention relates to an RFID-based wireless passive temperature measurement system and a wind power gear box system, and the system comprises a temperature sensor which comprises a temperature measurement chip and a sensor antenna; the reader is in communication connection with the temperature sensor, and the reader comprises a reader antenna which is used for transmitting a radio frequency signal; wherein the temperature sensor is a passive sensor arranged on the shaft surface of the high-speed rotating shaft, the reader antenna is an array antenna, the sensor antenna is a directional antenna, and the directional antenna generates an induced current through the radio frequency signal. And enough energy is provided for the temperature measurement chip in a short time when the temperature measurement chip rotates at a high speed for temperature measurement. Through the sensor antenna adopting a directional antenna and the reader antenna adopting an array antenna, the system has a higher link margin in a high-speed rotating complex operation environment, the link margin is received by the temperature measurement chip in a short time, and the problem that the energy obtained by the temperature measurement chip is insufficient during temperature measurement of a high-speed rotating shaft is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless monitoring, and in particular to a wireless passive temperature measurement system and a wind power gearbox system based on RFID. Background Art

[0002] The temperature of the high-speed shaft in the wind turbine gearbox is measured, and the temperature data obtained during the operation of the high-speed shaft is used to diagnose whether the wind turbine gearbox has a fault. However, it is often difficult to measure the temperature of the high-speed shaft.

[0003] In the related art, systems related to temperature measurement include: a wired temperature measurement system with a pulley, a wireless temperature measurement system with an active sensor, and a wireless temperature measurement system with a passive sensor.

[0004] For the wired temperature measurement system with a pulley, the installation and wiring of the system are complicated and not suitable for temperature measurement of a high-speed rotating shaft when it is running at high speed. For active sensors, the battery needs to be replaced after it is exhausted before it can be used, or a self-powered module needs to be designed. Due to the need for a battery module, the sensor is large in size, which has a certain impact on the operation of the high-speed shaft, and it is not convenient to install it on the shaft surface of the high-speed shaft. For passive sensors, the complexity of the high-speed shaft operating environment (oil, metal, high-speed rotation, etc.) makes the energy received by the passive sensors in the related art insufficient to complete the temperature measurement. Summary of the invention

[0005] In order to overcome the problems existing in the related art, the present disclosure provides a wireless passive temperature measurement system and a wind power gearbox system based on RFID.

[0006] According to a first aspect of an embodiment of the present disclosure, the present disclosure provides an RFID-based wireless passive temperature measurement system, comprising: a temperature sensor, comprising a temperature measuring chip and a sensor antenna; and a reader, which is communicatively connected to the temperature sensor, the reader comprising a reader antenna for transmitting a radio frequency signal; wherein the temperature sensor is a passive sensor arranged on the shaft surface of a high-speed rotating shaft, and the reader antenna is an array antenna and the sensor antenna is a directional antenna, the directional antenna generates an induced current through the radio frequency signal to provide sufficient energy for the temperature measuring chip in a short time when measuring temperature during high-speed rotation.

[0007] In some embodiments, the temperature measuring chip is welded and fixed to the sensor antenna.

[0008] In some embodiments, the directional antenna is a microstrip patch antenna that is resistant to metal interference and is used to adjust the impedance matching between the directional antenna and the temperature measurement chip.

[0009] In some embodiments, the temperature sensor is fixed to the shaft surface of the high-speed rotating shaft by glue and / or tape.

[0010] In some embodiments, the reader antenna is fixed in position and one is provided; and the temperature sensor rotates with the high-speed rotating shaft and one or more is provided.

[0011] In some embodiments, the reader further comprises a coaxial cable, wherein the reader antenna is located outside the reader and is electrically connected to the reader via the coaxial cable.

[0012] In some embodiments, the RFID-based wireless passive temperature measurement system further includes: a processing terminal; and a Zigbee module electrically connected to the processing terminal, wherein the Zigbee module is used to wirelessly transmit the data information collected by the reader to the processing terminal.

[0013] According to a second aspect of an embodiment of the present disclosure, the present disclosure provides a wind turbine gearbox system, comprising: a wind turbine gearbox comprising a high-speed rotating shaft; and an RFID-based wireless passive temperature measurement system as described in the first aspect, used to enable the temperature measuring chip to obtain energy in a short time during high-speed rotating temperature measurement.

[0014] In some embodiments, the wind turbine gearbox further comprises a box body, wherein the high-speed rotating shaft is located in the box body, the reader antenna is fixed in the box body, and the reader is located outside the box body.

[0015] In some embodiments, the high speed rotating shaft includes a bearing.

[0016] The technical solution provided by the embodiments of the present disclosure may include the following beneficial effects: by using a wireless passive temperature sensor, the influence of wiring and battery volume on the operation of a high-speed rotating shaft is avoided. At the same time, by using a sensor antenna with a directional antenna and a reader antenna with an array antenna, the system has a higher link margin in a complex operating environment of high-speed rotation, and can be received by the temperature measurement chip in a short time, so as to solve the problem that the temperature measurement chip cannot accurately and real-time measure the temperature due to insufficient energy when measuring the temperature of a high-speed rotating shaft. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present disclosure and, together with the description, serve to explain the principles of the present disclosure.

[0018] Figure 1 is a communication connection schematic diagram of a wireless passive temperature measurement system based on RFID according to an exemplary embodiment;

[0019] Figure 2 is a schematic structural diagram of an array antenna according to an exemplary embodiment;

[0020] Figures 3 to 5 These are the reflection coefficients in oil, bottom metal, and side metal environments, respectively. DETAILED DESCRIPTION

[0021] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0022] According to an embodiment of the present invention, the RFID-based wireless passive temperature measurement system is suitable for application in a wind turbine gearbox system, which includes a high-speed rotating shaft 50. In the present invention, unless otherwise specified, axial, radial and circumferential directions refer to the axial, radial and circumferential directions of the high-speed rotating shaft 50, respectively.

[0023] In order to solve the above technical problems, the present invention provides a wireless passive temperature measurement system based on RFID, such as Figure 1 As shown, the RFID-based wireless passive temperature measurement system is applied to a wind power gearbox system to monitor and obtain temperature data of a high-speed rotating shaft 50 in real time and accurately during high-speed operation.

[0024] The RFID-based wireless passive temperature measurement system includes a temperature sensor 10 , a reader 20 , a Zigbee module 30 and a processing terminal 40 .

[0025] The basic working principle of RFID is as follows: after the tag enters the magnetic field, it receives the radio frequency signal sent by the reader and uses the energy obtained by the induced current to send out the product information stored in the chip.

[0026] It can be seen that in the embodiment of the present disclosure, RFID refers to the temperature sensor 10 (equivalent to the above-mentioned tag) and the reader 20 (equivalent to the above-mentioned reader) being connected via wireless communication to transmit signals or data. The reader 20 transmits a radio wave (also known as electromagnetic wave, radio frequency signal) energy of a specific frequency to the temperature sensor 10 to drive the temperature sensor 10 to send out the internal signal or data.

[0027] Specifically, the temperature sensor 10 may include at least a temperature measuring chip and a sensor antenna 11 electrically connected to the temperature measuring chip. The reader 20 may include a reader antenna 21, which may be used to generate and transmit radio frequency signals for energy transmission and signal transmission.

[0028] The temperature sensor 10 may be a passive sensor, that is, no additional battery or cable is required to power the temperature sensor 10, and the temperature sensor 10 is fixed to the shaft surface of the high-speed rotating shaft 50 and rotates with the rotation of the high-speed rotating shaft 50. In some embodiments, the temperature sensor 10 may be fixed to the shaft surface of the high-speed rotating shaft 50 by glue and / or a tape 12, an adhesive tape, a binding tape, etc. The glue or tape prevents the temperature sensor 10 from being detached and facilitates the installation and removal of the temperature sensor 10.

[0029] The temperature sensor 10 is a wireless passive sensor. Compared with an active sensor, the wireless passive sensor does not require the installation of additional equipment, reduces the use of cables, avoids complex wiring, and is more suitable for the high-speed rotation environment of the high-speed rotating shaft 50. In addition, the wireless passive sensor does not need to install batteries, which reduces the weight and volume of the batteries, has little impact on the operation of the high-speed rotating shaft 50, is easy to install, and does not need to worry about running out of power, avoiding frequent battery replacement.

[0030] Furthermore, the reader antenna 21 is an array antenna and the sensor antenna 11 is a directional antenna. The directional antenna generates an induced current by receiving the radio frequency signal transmitted by the reader antenna 21, thereby providing sufficient energy for the temperature measuring chip in a short time when measuring temperature at high speed rotation, so that the temperature measuring chip transmits the temperature signal to the reader 20.

[0031] In this embodiment, when the sensor antenna 11 is aligned with the reader antenna 21 in the circumferential and radial directions, the energy received by the sensor antenna 11 is maximum. However, since the temperature sensor 10 rotates at a high speed with the high-speed rotating shaft 50, the sensor antenna 11 obtains energy in a very short time. Therefore, it is necessary to receive sufficient energy in a short time to measure the temperature of the high-speed rotating shaft 50. Therefore, a directional antenna with anti-metal interference function is used as the sensor antenna 11, and an array antenna with a higher gain is used as the reader antenna 21 (also called a reading antenna) for this purpose.

[0032] The directional antenna is a microstrip patch antenna that is resistant to metal interference. The working environment of the high-speed rotating shaft 50 includes oil and metal. The directional antenna that is resistant to metal interference can remove interference to receive more energy. The microstrip patch antenna is a structural form of a directional antenna. The microstrip patch antenna can realize the miniaturization of the sensor antenna 11. As can be seen from the above content, the temperature measurement chip is welded on the directional antenna and needs to achieve conjugate matching (also known as impedance matching) with the directional antenna. The microstrip patch antenna can be used to adjust the impedance matching between the directional antenna and the temperature measurement chip.

[0033] In addition, polyphenylene sulfide (hereinafter referred to as PPS) material can be used as the shell of the temperature sensor 10, and the temperature measuring chip and directional antenna are located inside the shell. PPS is a new type of high-performance thermoplastic resin with the advantages of high mechanical strength, high temperature resistance, chemical resistance, flame retardancy, good thermal stability, and excellent electrical properties.

[0034] The array antenna is an antenna system composed of many identical single antennas (such as symmetrical antennas) arranged in a certain pattern, also known as an antenna array. The independent units that make up the antenna array are called array elements or antenna units. Array antennas are often large in size. In order to reduce the size, materials with higher dielectric constants (such as ceramics) are used as the substrate of the array antenna. Taking into account the size and beam width, a 2x2 patch array antenna (linear polarization) is used as the reader antenna 21 (such as Figure 2 shown).

[0035] like Figures 3 to 5 The reflection coefficients of the directional antenna and array antenna of the above type obtained by HFSS simulation in different situations (oil, bottom metal, side metal) are shown. From the results, this type of sensor antenna 11 and reader antenna 21 are suitable for complex environments with oil, a large amount of metal and high-speed rotation.

[0036] Since the oil, bottom metal and side metal have little effect on the microstrip patch antenna, the link margin can be estimated. Formula 1 is the transmission loss formula, the frequency used is 902MHz-928MHz, and the distance between the reader antenna 21 and the sensor antenna 11 is assumed to be 5 meters (in fact, it is often less than 0.5 meters). Formula 2 uses the total transmission power of the reader antenna 21 (the peak gain obtained by simulation is 7.2dBi), the line loss of 5 meters RG316 (coaxial) is about 5.5dB, and the energy from the transmitter is 1W. Formula 3 is the sensor sensitivity formula, the peak gain of the outlet sensor antenna 11 is 3.5dBi, the sensitivity of the chip is 16dBm, the polarization loss is 3dB, and the efficiency of RF to DC is assumed to be 50% (3dB). Formula 4 is the link margin formula. According to the calculation results, its link margin is 19.7dB.

[0037] L=32.4+L d (dB)+L f (dB) = 32.4 + 20lgd + 20lgf ≈ 25.5dB Formula 1

[0038] P total transmit =P t -Loss line +G reader antenna =31.7dBm Formula 2

[0039] S sensor=S chip +G sensor antenna -Loss RF to DC -Loss polarization =13.5dBm Formula 3

[0040] F=P total transmit +S sensor -L=19.7dB Formula 4

[0041] It can be seen that by adopting the sensor antenna 11 of a directional antenna and the reader antenna 21 of an array antenna, the system has a higher link margin in a complex operating environment of high-speed rotation, and is received by the temperature measuring chip in a short time, thereby solving the problem of insufficient energy obtained by the temperature measuring chip when measuring the temperature of the high-speed rotating shaft 50.

[0042] In some embodiments, the temperature measuring chip is welded and fixed to the sensor antenna 11. The welding connection can not only fix the temperature measuring chip and the sensor antenna 11, but also electrically connect the two, so that the temperature measuring chip can receive the induced current induced by the sensor antenna 11, and transmit the collected temperature signal or other data through the sensor antenna 11. In this way, additional wiring and fixing devices are reduced, the volume of the temperature sensor 10 is reduced as much as possible, and the influence on the high-speed rotating shaft 50 rotating at high speed is avoided.

[0043] In some embodiments, the reader antenna 21 is fixed and one is provided; and the temperature sensor 10 rotates with the high-speed rotating shaft 50 and one or more are provided, wherein the number of temperature sensors 10 arranged depends on the cost and the size and structure of the high-speed rotating shaft 50 itself.

[0044] The position of the reader antenna 21 is aligned with the temperature sensor 10, especially with the sensor antenna 11 in the temperature sensor 10 in the radial direction of the high-speed rotating shaft 50. When the directional antenna of the temperature sensor 10 rotates with the high-speed rotating shaft 50, when the overlapping area with the array antenna of the reader antenna 21 is the largest, the energy generated by the directional antenna is also the largest.

[0045] In addition, if multiple directional antennas are arranged, they can be arranged at equal or unequal intervals along the circumference of the high-speed rotating shaft 50 to obtain the temperature of each preset position along the circumference of the high-speed rotating shaft 50, thereby more comprehensively and specifically monitoring the temperature of the high-speed rotating shaft 50 to accurately predict whether a fault occurs and the location where it occurs. In addition, multiple temperature sensors 10 can also be arranged at intervals along the axial direction.

[0046] In some embodiments, Figure 1As shown, the reader 20 also includes a coaxial cable 22, wherein the reader antenna 21 is located outside the reader 20 and is electrically connected to the reader 20 through the coaxial cable 22. Specifically, the wind turbine gearbox includes a housing, the reader antenna 21 and the reader 20 are separately arranged, and the reader antenna 21 is located in the housing, so that the sensor antenna 11 receives energy and receives the temperature signal of the temperature measurement chip. The reader 20 can be located outside the housing through the coaxial cable 22, so that the collected or acquired temperature signal is transmitted to the external processing terminal 40, and the reader 20 is prevented from occupying the volume in the housing of the wind turbine gearbox.

[0047] In some embodiments, the RFID-based wireless passive temperature measurement system also includes a processing terminal 40 and a Zigbee module 30. The Zigbee module 30 is electrically connected to the processing terminal 40. The Zigbee module 30 is used to receive the data signal collected and transmitted by the reader 20, and wirelessly transmit the data information to the processing terminal 40 for processing.

[0048] Among them, the Zigbee module 30 is a new technology for deploying wireless sensor networks, which belongs to a communication protocol and can perform short-distance, low-rate wireless data transmission. In some other embodiments, other wireless communication protocols can also be used between the processing terminal 40 and the reader 20, which are not listed here one by one.

[0049] Based on the same inventive concept, the present disclosure provides a wind power gearbox system, including: a wind power gearbox including a high-speed rotating shaft 50; and a wireless passive temperature measurement system based on RFID as described above, which is used to enable the temperature measuring chip to obtain energy in a short time during high-speed rotating temperature measurement.

[0050] In some embodiments, the wind turbine gearbox further includes a box body (not shown in the figure), wherein the high-speed rotating shaft 50 is located in the box body, the reader antenna 21 is fixed in the box body, and the reader 20 is located outside the box body.

[0051] In some embodiments, the high-speed rotating shaft 50 includes a bearing, that is, the RFID-based wireless passive temperature measurement system can be applied not only to the high-speed rotating shaft, but also to the high-speed rotating bearing to measure the temperature of the high-speed rotating shaft 50 bearing.

[0052] In addition, the RFID-based wireless passive temperature measurement system can also be compatible and applied to other high-speed rotation or non-high-speed rotation environments. The RFID-based wireless passive temperature measurement system has a wide range of applications, which are not listed here one by one.

[0053] The specific manner in which the functions implemented in the wind turbine gearbox in the above embodiment have been described in detail in the embodiment of the RFID-based wireless passive temperature measurement system, and will not be elaborated here.

[0054] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the specification and practicing the invention disclosed herein. This application is intended to cover any modification, use or adaptation of the present disclosure, which follows the general principles of the present disclosure and includes common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the following scope of rights.

[0055] It should be understood that the present disclosure is not limited to the precise structures that have been described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the scope of the appended claims.

Claims

1. A wireless passive temperature measurement system based on RFID, characterized in that: include: A temperature sensor (10), comprising a temperature measurement chip and a sensor antenna (11); as well as A reader (20) is communicatively connected to the temperature sensor (10), wherein the reader (20) comprises a reader antenna (21) for transmitting a radio frequency signal; The temperature sensor (10) is a passive sensor arranged on the surface of a high-speed rotating shaft (22), the reader antenna (21) is an array antenna, and the sensor antenna (11) is a directional antenna. The directional antenna generates an induced current through the radio frequency signal to provide sufficient energy for the temperature measuring chip in a short time during high-speed rotating temperature measurement.

2. The RFID-based wireless passive temperature measurement system according to claim 1, characterized in that: The temperature measuring chip is welded and fixed to the sensor antenna (11).

3. The RFID-based wireless passive temperature measurement system according to claim 1, characterized in that: The directional antenna is a microstrip patch antenna that is resistant to metal interference and is used to adjust the impedance matching between the directional antenna and the temperature measurement chip.

4. The RFID-based wireless passive temperature measurement system according to claim 1, characterized in that: The temperature sensor (10) is fixed to the shaft surface of the high-speed rotating shaft (22) by means of glue and / or a tape (12).

5. The RFID-based wireless passive temperature measurement system according to claim 1, characterized in that: The reader antenna (21) is fixed in position and is provided in one piece; and The temperature sensor (10) rotates with the high-speed rotating shaft (22) and one or more temperature sensors are provided.

6. The RFID-based wireless passive temperature measurement system according to claim 1, characterized in that: The reader (20) further comprises a coaxial cable (21), The reader antenna (21) is located outside the reader (20) and is electrically connected to the reader (20) via the coaxial cable (21).

7. The RFID-based wireless passive temperature measurement system according to claim 1, characterized in that: Also includes: Processing terminal (40); as well as A Zigbee module (30) is electrically connected to the processing terminal (40), and the Zigbee module (30) is used to wirelessly transmit the data information collected by the reader (20) to the processing terminal (40).

8. A wind power gearbox system, characterized in that: include: A wind power gearbox, comprising a high-speed rotating shaft (22); The RFID-based wireless passive temperature measurement system according to any one of claims 1 to 7 is used to enable the temperature measurement chip to obtain energy in a short time when measuring temperature during high-speed rotation.

9. The wind turbine gearbox system according to claim 8, characterized in that: The wind power gearbox also includes a box body, The high-speed rotating shaft (22) is located inside the box, the reader antenna (21) is fixed inside the box, and the reader (20) is located outside the box.

10. The wind power gearbox system according to claim 8, characterized in that: The high-speed rotating shaft (22) includes a bearing.

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