Surface acoustic wave sensor temperature measurement and distance measurement integrated device in switch cabinet

Abstract

The invention discloses a temperature measurement and distance measurement integrated device for surface acoustic wave sensors in a switch cabinet, and relates to the field of measurement, and the temperature measurement and distance measurement integrated device for the surface acoustic wave sensors in the switch cabinet comprises a sensor unit which is used for transmitting frequency signals to a signal collector through two surface acoustic wave sensors with different working frequencies at the same time, the two frequency signals reflect temperature information and distance information of the switch cabinet where the two surface acoustic wave sensors are located; compared with the prior art, the system has the beneficial effects that by using the two surface acoustic wave sensors, both temperature measurement and distance measurement are realized, the distance value of the sensor corresponding to the temperature value can be accurately obtained, the problem of signal interference of multiple sensors is solved, and the accuracy and reliability of temperature monitoring in the switch cabinet are improved; the two surface acoustic wave sensors are integrated in the same chip and share the substrate, the electrode and the antenna, each sensor can measure the temperature and the phase and estimate the distance, and the number and complexity of the sensors are reduced.

Description

Technical Field

[0001] This invention relates to the field of measurement, specifically to an integrated device for temperature and distance measurement using a surface acoustic wave sensor inside a switch cabinet. Background Technology

[0002] Switchgear is a crucial component of power systems, and monitoring its internal temperature is essential for ensuring the safe operation of power equipment. While traditional surface acoustic wave (SAW) sensors can achieve real-time monitoring of the internal temperature of switchgear, the limited shielding and isolation of the switchgear makes them prone to crosstalk between sensor signals. In multi-sensor environments, the measured signal may exhibit multiple sensor peaks, making it difficult to accurately identify whether the signal originates from a nearby sensor within the same cavity or from a sensor in an adjacent cavity. This reduces the accuracy and reliability of the monitoring, necessitating improvements. Summary of the Invention

[0003] The purpose of this invention is to provide an integrated device for temperature and distance measurement using a surface acoustic wave sensor in a switch cabinet, so as to solve the problems mentioned in the background art.

[0004] To achieve the above objectives, the present invention provides the following technical solution:

[0005] A surface acoustic wave sensor integrated device for temperature and distance measurement in a switch cabinet includes:

[0006] The sensor unit is used to simultaneously send frequency signals to the signal acquisition unit through two surface acoustic wave sensors with different operating frequencies. The two frequency signals reflect the temperature and distance information of the switch cabinet where the two surface acoustic wave sensors are located.

[0007] The signal acquisition unit is used to acquire two frequency signals, output them to the signal processing module, and estimate the distance to the sensor by the phase difference between the two frequency signals, obtain the distance value, and output it to the signal processing module.

[0008] The signal processing module is used to calculate the temperature value of the sensor based on the offset of the two frequency signals relative to the operating frequencies of the two surface acoustic wave sensors; and outputs the temperature value and distance value to the data transmission module.

[0009] The data transmission module is used to transmit the obtained temperature and distance values ​​to the monitoring system;

[0010] The output of the sensor unit is connected to the input of the signal acquisition unit, the output of the signal acquisition unit is connected to the input of the signal processing module, the output of the signal processing module is connected to the input of the data transmission module, and the output of the data transmission module is connected to the input of the monitoring system.

[0011] As a further aspect of the present invention, the operating frequency ratio of the two surface acoustic wave sensors is 11:10 to 15:10.

[0012] As a further aspect of the present invention, the operating frequencies of the two surface acoustic wave sensors are 480 MHz and 433 MHz, respectively.

[0013] As a further embodiment of the present invention: two surface acoustic wave sensors are integrated into the same chip, sharing a substrate, electrodes, and antenna.

[0014] As a further aspect of the present invention: the signal acquisition unit has a built-in phase difference measurement module. The phase difference measurement module performs signal demodulation based on the least squares algorithm, calculates the phase difference between two frequency signals, and then estimates the distance to the sensor.

[0015] As a further aspect of the present invention: the monitoring system analyzes the temperature and distance information of the switch cabinet where the two surface acoustic wave sensors are located in real time based on temperature and distance values.

[0016] As a further aspect of the present invention: the monitoring system displays data, including the acquired temperature values, distance values, and the temperature and distance information of the switchgear obtained through real-time analysis.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows: The present invention achieves both temperature measurement and distance measurement by using two surface acoustic wave sensors, which can accurately determine the distance value of the sensor corresponding to the temperature value, solve the problem of multi-sensor signal interference, and improve the accuracy and reliability of temperature monitoring inside the switch cabinet; the two surface acoustic wave sensors are integrated in the same chip, sharing the substrate, electrodes and antenna, and each sensor can measure both temperature and phase to estimate distance, reducing the number and complexity of sensors. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of an integrated surface acoustic wave sensor for temperature and distance measurement in a switch cabinet. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0020] Please see Figure 1 A surface acoustic wave sensor integrated device for temperature and distance measurement in a switch cabinet, comprising:

[0021] The sensor unit is used to simultaneously send frequency signals to the signal acquisition unit through two surface acoustic wave sensors with different operating frequencies. The two frequency signals reflect the temperature and distance information of the switch cabinet where the two surface acoustic wave sensors are located.

[0022] The signal acquisition unit is used to acquire two frequency signals, output them to the signal processing module, and estimate the distance to the sensor by the phase difference between the two frequency signals, obtain the distance value, and output it to the signal processing module.

[0023] The signal processing module is used to calculate the temperature and distance of the sensors based on the offset of two frequency signals relative to the operating frequencies of the two surface acoustic wave (SAW) sensors. The details are as follows: First, the signal processing module estimates the instantaneous frequencies fH and fL of the high-frequency and low-frequency echoes through frequency measurement. Subtracting their respective nominal frequencies fH0 = 480 MHz and fL0 = 433 MHz yields ΔfH and ΔfL. The temperature T is then calculated using the temperature-frequency ratio of the two SAW devices. Simultaneously, a cosine-sine matrix is ​​constructed for the two baseband echo sequences within the same sliding window. The least squares algorithm is used to estimate the high-frequency phase φH and the low-frequency phase φL in one step. After phase unwrapping, the difference Δφ = φH - φL is taken. The distance is then calculated using τ = Δφ / [2π(fH - fL)] and d = cτ / 2. Finally, the temperature T and distance d are packaged and sent to the data transmission module.

[0024] The data transmission module is used to transmit the obtained temperature and distance values ​​to the monitoring system;

[0025] The output of the sensor unit is connected to the input of the signal acquisition unit, the output of the signal acquisition unit is connected to the input of the signal processing module, the output of the signal processing module is connected to the input of the data transmission module, and the output of the data transmission module is connected to the input of the monitoring system.

[0026] In a specific embodiment: Please refer to Figure 1 Due to the dynamic influence of temperature and distance, the actual output frequency ratio of the two surface acoustic wave (SAW) sensors will deviate from the operating frequency ratio of the two SAW sensors. This deviation is analyzed to achieve temperature and distance measurement functions. The sensor unit integrates two SAW sensors, one high-frequency and one low-frequency, both integrated into the same chip. The high-frequency SAW sensor operates at 480MHz, and the low-frequency SAW sensor operates at 433MHz; both are used for temperature and phase measurement. The signal acquisition unit receives the high-frequency and low-frequency signals sent by the sensor unit, calculates the phase difference through the phase difference measurement module, and then estimates the sensor distance. The signal processing module calculates the temperature value based on the frequency changes of the high-frequency and low-frequency signals. The data transmission module sends the processed temperature and distance values ​​to the monitoring system, which performs real-time analysis and display of the data.

[0027] In this embodiment: Please refer to Figure 1 The operating frequency ratio of the two surface acoustic wave sensors is 11:10 to 15:10.

[0028] The frequency ratio range is designed primarily based on the collaborative measurement requirements of dual-frequency signals. The frequency ratio between the high-frequency (e.g., 480MHz) and low-frequency (e.g., 433MHz) sensors must meet the following conditions: the high-frequency signal is more sensitive to temperature changes, while the low-frequency signal exhibits better phase stability during long-distance transmission. A ratio of 11:10 to 15:10 ensures that the frequency offset difference between the two signals is sufficient for temperature calculation while avoiding signal interference caused by frequencies being too close. Furthermore, this range ensures that the phase difference measurement resolution meets the millimeter-level ranging accuracy requirements within the switchgear.

[0029] In this embodiment: Please refer to Figure 1 The two surface acoustic wave sensors operate at frequencies of 480 MHz and 433 MHz, respectively.

[0030] The 480MHz high-frequency design improves temperature detection sensitivity, as the propagation speed of high-frequency surface acoustic waves is more significantly affected by temperature; the 433MHz low-frequency design optimizes signal penetration and anti-attenuation capabilities, making it suitable for long-distance transmission in metal-shielded environments within switch cabinets; both frequencies belong to the ISM band, requiring no additional spectrum license application and having lower hardware implementation costs; the dual-frequency combination can also eliminate environmental noise and improve the signal-to-noise ratio through differential processing.

[0031] In this embodiment: Please refer to Figure 1 Two surface acoustic wave sensors are integrated into the same chip, sharing a substrate, electrodes, and antenna.

[0032] The integrated design and shared structure significantly reduce sensor size (suitable for confined spaces in switch cabinets), while also lowering power consumption and hardware costs. Dual sensors on the same chip have consistent environmental parameters (such as substrate temperature stress), eliminating measurement errors caused by differences in installation location. Furthermore, the integrated design simplifies the interface complexity of the signal acquisition unit and improves system reliability.

[0033] In this embodiment: Please refer to Figure 1The signal acquisition unit has a built-in phase difference measurement module. This module uses a least squares algorithm to demodulate the signal, calculate the phase difference between two frequency signals, and then estimate the distance to the sensor. Details are as follows: After obtaining the high-frequency and low-frequency echoes, the signal acquisition unit directly establishes a cosine-sine matrix from the complex baseband sampling sequences xH[n] and xL[n]. It then uses a first least squares algorithm to obtain the respective phases φH and φL, unwrappes the signals, and takes the difference Δφ = φH - φL. Finally, it converts this difference into the distance from the sensor to the read / write antenna using d = c·Δφ / [4π(fH0 - fL0)], thus completing the distance measurement.

[0034] The least squares algorithm can effectively suppress phase measurement deviations caused by electromagnetic interference and multipath effects in the switch cabinet by minimizing the sum of squared errors.

[0035] In this embodiment: Please refer to Figure 1 The monitoring system analyzes the temperature and distance information of the switch cabinet where the two surface acoustic wave sensors are located in real time based on temperature and distance values.

[0036] Real-time analysis can instantly identify faults such as abnormal temperatures (e.g., overheating of contacts), and can further trigger early warnings by setting thresholds to prevent switchgear from overheating and exploding.

[0037] In this embodiment: Please refer to Figure 1 The monitoring system displays the acquired temperature and distance values, as well as the temperature and distance information of the switchgear obtained through real-time analysis.

[0038] The system visually displays temperature and distance values, which can help maintenance personnel quickly locate the abnormal temperature points when abnormal temperatures are detected.

[0039] The working principle of this invention is as follows: The sensor unit simultaneously sends frequency signals to the signal acquisition unit through two surface acoustic wave (SAW) sensors with different operating frequencies. The two frequency signals reflect the temperature and distance information of the switchgear where the two SAW sensors are located. The signal acquisition unit collects the two frequency signals, outputs them to the signal processing module, and estimates the distance between the sensors by the phase difference between the two frequency signals, obtaining the distance value, and outputting it to the signal processing module. The signal processing module calculates the temperature value of the sensors based on the offset of the two frequency signals relative to the operating frequencies of the two SAW sensors. The temperature value and distance value are output to the data transmission module. The data transmission module transmits the obtained temperature value and distance value to the monitoring system.

[0040] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and not restrictive.

[0041] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A surface acoustic wave sensor integrated device for temperature and distance measurement in a switch cabinet, characterized in that, The integrated surface acoustic wave sensor for temperature and distance measurement in the switch cabinet includes: The sensor unit is used to simultaneously send frequency signals to the signal acquisition unit through two surface acoustic wave sensors with different operating frequencies. The two frequency signals reflect the temperature and distance information of the switch cabinet where the two surface acoustic wave sensors are located. The signal acquisition unit is used to acquire two frequency signals, output them to the signal processing module, and estimate the distance to the sensor by the phase difference between the two frequency signals, obtain the distance value, and output it to the signal processing module. The signal processing module is used to calculate the temperature value of the sensor based on the offset of the two frequency signals relative to the operating frequencies of the two surface acoustic wave sensors; and outputs the temperature value and distance value to the data transmission module. The data transmission module is used to transmit the obtained temperature and distance values ​​to the monitoring system; The output of the sensor unit is connected to the input of the signal acquisition unit, the output of the signal acquisition unit is connected to the input of the signal processing module, the output of the signal processing module is connected to the input of the data transmission module, and the output of the data transmission module is connected to the input of the monitoring system.

2. The integrated surface acoustic wave sensor temperature and distance measurement device for switchgear as described in claim 1, characterized in that, The operating frequency ratio of the two surface acoustic wave sensors is 11:10 to 15:

10.

3. The integrated surface acoustic wave sensor temperature and distance measurement device for switchgear as described in claim 2, characterized in that, The two surface acoustic wave sensors operate at frequencies of 480 MHz and 433 MHz, respectively.

4. The integrated surface acoustic wave sensor temperature and distance measurement device for switchgear as described in any one of claims 1 to 3, characterized in that, Two surface acoustic wave sensors are integrated into the same chip, sharing a substrate, electrodes, and antenna.

5. The integrated surface acoustic wave sensor temperature and distance measurement device for switchgear as described in claim 1, characterized in that, The signal acquisition unit has a built-in phase difference measurement module. The phase difference measurement module demodulates the signal based on the least squares algorithm, calculates the phase difference between two frequency signals, and then estimates the distance to the sensor.

6. The integrated surface acoustic wave sensor temperature and distance measurement device for switchgear as described in claim 1, characterized in that, The monitoring system analyzes the temperature and distance information of the switch cabinet where the two surface acoustic wave sensors are located in real time based on temperature and distance values.

7. The integrated surface acoustic wave sensor temperature and distance measurement device for switchgear as described in claim 1, characterized in that, The monitoring system displays data, including the acquired temperature and distance values, as well as the temperature and distance information of the switchgear obtained through real-time analysis.

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