Noise on-line monitoring device for electric power facilities and application method of noise on-line monitoring device

Abstract

The invention discloses a noise on-line monitoring device for electric power facilities and an application method thereof.A host of the noise on-line monitoring device comprises an outdoor rainproof junction box, a waterproof shielding shell and a circuit unit, the waterproof shielding shell is installed in the outdoor rainproof junction box, and the circuit unit is installed in the waterproof shielding shell; a GPS antenna, a communication antenna and a weather station are installed on the outdoor rainproof junction box, a battery pack is installed in the outdoor rainproof junction box, the outdoor microphone array is fixedly installed on the outdoor rainproof junction box or fixedly installed at a factory boundary measuring point of a transformer substation, the outdoor microphone array comprises a plurality of microphones, and the microphones are connected with the outdoor rainproof junction box. And the microphone, the GPS antenna, the communication antenna, the meteorological station and the battery pack are respectively connected with the circuit unit. The device is compact in structure and long in endurance, has an anti-interference monitoring capability, is suitable for online noise monitoring of electric power facilities such as a transformer substation and a converter station, can improve the quality and efficiency of environment-friendly noise monitoring and prevention work of the electric power facilities, and reduces the monitoring cost.

Description

Technical Field

[0001] This invention belongs to the field of acoustic measurement technology, specifically relating to an online noise monitoring device for power facilities and its application method. Background Technology

[0002] With economic and social development, people have increasingly higher requirements for the quality of the acoustic environment, and noise problems from substations, converter stations, and transmission lines are receiving more and more attention. As an important component of the environmental monitoring system, online noise monitoring devices are increasingly used for environmental noise monitoring of power facilities, enabling data acquisition and traceability of noise pollution. In actual substation boundary noise monitoring work, it has been found that measurements are often interfered with by various surrounding environmental noises, such as vehicle noise, residential noise, and industrial noise from factories. These interferences significantly affect measurement accuracy and work efficiency. Therefore, online noise monitoring devices that combine long-term online monitoring and anti-interference capabilities are an effective solution to this problem. Currently, there are two main types of online noise monitoring devices: fixed and mobile. Fixed devices are commonly used for long-term monitoring and evaluation of the acoustic environment. Their disadvantage is that the monitoring equipment requires a fixed power supply for continuous operation, making construction more complex, limiting mobile monitoring, and resulting in higher investment and maintenance costs. Portable noise monitoring devices typically add communication modules and power batteries to conventional noise monitoring equipment, allowing for flexible movement and monitoring. However, they often lack a systematic low-power design; even during periods without data acquisition and transmission, modules may still be operational, leading to rapid energy consumption. They are suitable for short-term monitoring, such as 24 hours or 1-2 days. Furthermore, because anti-interference algorithms are usually complex, requiring powerful circuit boards and consuming significant power, conventional portable noise monitoring devices cannot provide long-term online monitoring and anti-interference capabilities for mobile substation boundary noise monitoring. In general, conventional online noise monitoring devices are usually general-purpose models, primarily for environmental noise monitoring. They typically only require sound pressure level calculations, resulting in limited computing power and difficulty meeting the anti-interference monitoring needs of relevant substation boundary noise monitoring. Alternatively, they may use general-purpose signal acquisition devices with slight modifications for substation boundary noise monitoring, which is cumbersome and inflexible. Summary of the Invention

[0003] The technical problem to be solved by the present invention is to provide a noise online monitoring device and its application method for power facilities that is compact in structure, has long endurance, has anti-interference monitoring capabilities, and is suitable for applications in power facilities such as substations and converter stations, so as to improve the quality and efficiency of environmental noise monitoring and prevention work in power facilities and reduce monitoring costs.

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: An online noise monitoring device for power facilities includes a main unit and an outdoor microphone array. The main unit includes an outdoor rainproof junction box, a waterproof shielding shell, and a circuit unit. The waterproof shielding shell is installed inside the outdoor rainproof junction box, and the circuit unit is installed inside the waterproof shielding shell. A GPS antenna, a communication antenna, and a weather station are respectively installed on the outdoor rainproof junction box. A battery pack is installed inside the outdoor rainproof junction box. The outdoor microphone array is installed and fixed on the outdoor rainproof junction box or fixedly installed at the boundary measurement point of the substation. The outdoor microphone array includes multiple microphones with self-calibration function. The microphones, GPS antenna, communication antenna, weather station, and battery pack are respectively connected to the circuit unit.

[0005] Optionally, the circuit unit includes a processor, a communication and GPS module, an RS485 transceiver, a power management circuit, and a sound acquisition circuit corresponding to each microphone. The processor is connected to the communication and GPS module, the RS485 transceiver, the power management circuit, and the sound acquisition circuit, respectively. The microphone is connected to the sound acquisition circuit. The GPS antenna and the communication antenna are connected to the communication and GPS module, respectively. The weather station is connected to the RS485 transceiver, and the battery pack is connected to the power management circuit to supply power to the circuit unit.

[0006] Optionally, the sound acquisition circuit includes a constant current source, a signal conditioning circuit, an analog-to-digital converter (ADC), and a self-calibration component. The power management circuit supplies power to the microphone through the constant current source. The output terminal of the microphone is connected in sequence through the signal conditioning circuit, the ADC, and the input terminal of the processor. The control terminal of the microphone is connected to the output terminal of the processor through the self-calibration component.

[0007] Optionally, the self-calibration component includes a DC-DC module, a filter, a DC amplification module, a signal generator, an AC amplification module, and an electrostatic exciter. The output of the DC-DC module is sequentially connected to the filter and the DC amplification module to form a DC bias voltage on the electrostatic exciter. The control terminal of the signal generator is connected to the output terminal of the processor. The output terminal of the signal generator is connected to the electrostatic exciter through both the DC amplification module and the AC amplification module to generate a calibration excitation signal. The electrostatic exciter and the sensitive element of the microphone form two electrodes in a capacitor.

[0008] Optionally, the electrostatic exciter is a circular metal plate with holes or a grid.

[0009] Optionally, the outdoor microphone array comprises a telescopic rod, a connecting rod, and a windproof cover connected in sequence. The microphone is installed inside the windproof cover, and the base of the telescopic rod is fixed to an outdoor rainproof junction box or fixedly installed at a measuring point at the boundary of the substation.

[0010] Optionally, the outdoor rainproof junction box is also equipped with a display screen and a button module, which are electrically connected to the circuit unit installed inside the waterproof shielding shell.

[0011] Optionally, the outdoor rainproof junction box is also externally equipped with a solar panel, which is electrically connected to the circuit unit installed inside the waterproof shielding shell, for powering the circuit unit and charging the battery to enable long-term monitoring.

[0012] A method for applying the aforementioned online noise monitoring device for power facilities includes the following steps: S101, the working state of the circuit unit is controlled by the hardware timer in the circuit unit based on the set start time period. If the current time is within the set start time period, the circuit unit is started and the process jumps to step S102; if the current time is outside the start time period, the circuit unit is put into sleep or turned off and the process jumps to step S101. S102 uses an intermittent strategy to perform online noise detection of power facilities at a preset detection cycle.

[0013] Optionally, the online noise detection of power facilities includes: S201, the processor of the control circuit unit enters the energy-saving mode. In the energy-saving mode, the circuit unit detects the noise signal through a designated microphone in the outdoor microphone array and calculates the noise sound pressure level by integration, as well as the wind speed and rainfall measured by the weather station. S202, determine whether the wind speed exceeds the preset wind speed threshold or the rainfall exceeds the preset rainfall threshold. If it does, the meteorological conditions are not met and the test ends. Otherwise, determine whether the noise sound pressure level exceeds the preset threshold. If the noise sound pressure level does not exceed the preset threshold, the test ends. If the noise sound pressure level exceeds the preset threshold, proceed to step S203. S203, the processor of the control circuit unit enters the normal mode, and the circuit unit collects noise data through multiple microphones in the outdoor microphone array in the normal mode. S204, determine whether the communication signal strength of the communication and GPS modules in the circuit unit meets the requirements. If the requirements are met, send the collected noise data to the remote server. If there is unsent noise data in the local cache, send the cached noise data to the remote server as well; otherwise, cache the noise data locally. S205, the remote server uses multiple preset microphone array-based noise detection algorithms to obtain noise detection results from the noise data collected by multiple microphones. If the minimum value of all noise detection results is greater than the preset standard limit, the substation is determined to have excessive noise; if the maximum value of all noise detection results is less than or equal to the preset standard limit, the substation is determined to have compliant noise.

[0014] Compared with existing technologies, the present invention mainly achieves the following beneficial effects: The noise online monitoring device of the present invention adopts a highly integrated integrated structural design, achieving a compact structure suitable for mobile practicality. It employs multiple microphones with self-calibration functions to enable the simultaneous operation of various anti-interference algorithms. It achieves long battery life through the use of low-power control strategies, possessing the advantages of powerful functionality and adaptability to power facility noise monitoring. It also features a compact structure, long battery life, and anti-interference monitoring capabilities. While meeting the requirements for long-term noise monitoring, the noise online monitoring device of the present invention possesses multiple anti-external noise interference monitoring functions, providing a powerful and easy-to-use tool for noise monitoring at the substation boundary in complex environments. It is particularly suitable for online noise monitoring of power facilities such as substations and converter stations, improving the quality and efficiency of environmental noise monitoring and prevention work in power facilities and reducing monitoring costs. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the online noise monitoring device in an embodiment of the present invention.

[0016] Figure 2 This is a schematic diagram of the circuit principle of the online noise monitoring device in an embodiment of the present invention.

[0017] Figure 3 This is a schematic diagram of the circuit principle of the self-calibration component in an embodiment of the present invention.

[0018] Legend: 1. Main unit; 11. Outdoor rainproof junction box; 12. Waterproof shielding shell; 13. Circuit unit; 2. Outdoor microphone array; 21. Telescopic pole; 22. Connecting pole; 23. Windproof cover; 3. GPS antenna; 4. Communication antenna; 5. Weather station; 6. Battery pack; 7. Display screen; 8. Button module; 9. Solar panel. Detailed Implementation

[0019] To enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions of the present invention will be further described in detail below with reference to the accompanying drawings in the embodiments of the present invention.

[0020] like Figure 1As shown, the noise online monitoring device for power facilities in this embodiment includes a main unit 1 and an outdoor microphone array 2. The main unit 1 includes an outdoor rainproof junction box 11, a waterproof shielding shell 12, and a circuit unit 13. The waterproof shielding shell 12 is installed inside the outdoor rainproof junction box 11, and the circuit unit 13 is installed inside the waterproof shielding shell 12. A GPS antenna 3, a communication antenna 4, and a weather station 5 are respectively installed on the outdoor rainproof junction box 11. A battery pack 6 is installed inside the outdoor rainproof junction box 11. The outdoor microphone array 2 is fixedly installed on the outdoor rainproof junction box 11 (or it can be fixedly installed at the boundary measuring point of the substation). The outdoor microphone array 2 includes multiple microphones with self-calibration function. The microphones, GPS antenna 3, communication antenna 4, weather station 5, and battery pack 6 are respectively connected to the circuit unit 13. Figure 2 As shown, the circuit unit 13 in this embodiment includes a processor, a communication and GPS module, an RS485 transceiver, a power management circuit, and sound acquisition circuits corresponding to the microphones. The processor is connected to the communication and GPS module, the RS485 transceiver, the power management circuit, and the sound acquisition circuits. The microphones are connected to the sound acquisition circuits. The GPS antenna 3 and the communication antenna 4 are connected to the communication and GPS module, respectively. The weather station 5 is connected to the RS485 transceiver. The battery pack 6 is connected to the power management circuit to power the circuit unit 13. Furthermore, the circuit unit 13 in this embodiment is equipped with a removable SD card, which can be used to store collected data and calculation results.

[0021] In this embodiment, the STMicroelectronics STM32H743BIT is used as the processor. This processor is a microcontroller based on the ARM Cortex-M7 core, with a maximum clock frequency of 480MHz. The processor supports three low-power modes: sleep mode, stop mode, and standby mode. In standby mode, the current draw is only 5mA, and it can be flexibly switched according to work requirements.

[0022] In this embodiment, the processor communicates wirelessly with the control center via the communication and GPS modules, and uses GPS time synchronization to ensure time synchronization between multiple online noise monitoring devices and between the online noise monitoring devices and the control center. For long-distance data transmission, 4G is the most suitable wireless communication method. Therefore, the communication module in this embodiment uses the EC200S module. The EC200S module is Quectel's recently launched LTE Cat 1 wireless communication module, supporting a maximum downlink rate of 10 Mbps and a maximum uplink rate of 5 Mbps, offering excellent cost-effectiveness. It is also compatible with Quectel's multi-network standard LTE Standard EC200T series, EC2x (EC25, EC21, EC20 R2.1 and EC20-CN) series, EG2x-G (EG21-G and EG25-G) modules, and UMTS / HSPA+ UC200T series modules. The EC200S module also supports standard Mini PCIe packaging to meet the application needs of different industries. Regarding low power consumption, the enhanced sleep mode allows the module to quickly enter sleep mode after transmitting data. Its enhanced sleep mode differs from the normal sleep mode (controlled via AT+QSCLK; details about this AT command are mainly relevant in scenarios with intervals between data transmission and reception. After data transmission and reception are completed, the enhanced sleep mode can quickly enter a sleep state, thereby reducing the overall average power consumption). Given the 4G communication method, the data transmission protocol is planned to be MQTT (Message Queuing Telemetry Transport). MQTT is a lightweight communication protocol based on a publish / subscribe model. Its greatest advantage lies in its ability to provide real-time and reliable messaging services to connected remote devices with minimal code and limited bandwidth. As a low-overhead, low-bandwidth instant messaging protocol, it has wide applications in the Internet of Things, small devices, and mobile applications.

[0023] like Figure 2 As shown, the sound acquisition circuit in this embodiment includes a constant current source, a signal conditioning circuit, an analog-to-digital converter (ADC), and a self-calibration component. The power management circuit supplies power to the microphones via the constant current source. The microphone output is connected sequentially through the signal conditioning circuit, the ADC, and the processor input. The microphone control is connected to the processor output via the self-calibration component. In this embodiment, the outdoor microphone array 2 includes three microphones with self-calibration functionality. The microphones are high-precision condenser microphones, supporting three-channel operation. All are driven by a constant current source and equipped with a self-calibration circuit. The microphones use a 24-bit I2S interface ADC for analog-to-digital conversion.

[0024] like Figure 3 As shown, the self-calibration component in this embodiment includes a DC-DC module, a filter, a DC amplification module, a signal generator, an AC amplification module, and an electrostatic exciter. The configured electrostatic exciter is used for self-calibration design. The output of the DC-DC module forms a DC bias voltage on the electrostatic exciter through the filter and the DC amplification module. The control terminal of the signal generator is connected to the output of the processor. The output of the signal generator is connected to the electrostatic exciter through both the DC amplification module and the AC amplification module to generate a calibration excitation signal. The electrostatic exciter and the sensitive element of the microphone form two electrodes in a capacitor. As an optional implementation, the electrostatic exciter in this embodiment is a circular metal plate with holes or a grid. When a time-varying voltage is applied between the electrostatic exciter and the sensitive element of the microphone, a time-varying electrostatic force is formed on the sensitive element of the microphone. This electrostatic force excites the sensitive element of the microphone, thereby measuring the frequency response of the sensitive element of the microphone. Typically, the circuit generates an 800V high-voltage electric field (800V is the preferred value, which can be adjusted according to the microphone's sensitivity) between the microphone diaphragm and the electrostatic exciter grid, simulating changes in the sound pressure field to obtain the microphone's electrostatic exciter response. At the front end of the excitation section is a DC-DC module that converts the input DC power to 15V DC. During testing, significant ripple was observed in the 15V DC voltage output from the DC-DC module. Analysis revealed that the ripple energy is distributed at the oscillation frequency and its harmonics of the DC-DC module. Since the signal generator output is a small signal, ripple interference must be eliminated. To prevent ripple signal interference with the system, a filter module is connected after the DC-DC module to remove ripple signal interference. After filtering, the ripple is effectively attenuated. In the electrostatic exciter calibration method, an 800V DC bias voltage needs to be applied between the condenser microphone diaphragm and the electrostatic exciter. Therefore, the ripple-attenuated 15V DC outputs as 800V DC after passing through a DC amplifier module. The 15V voltage, after ripple attenuation, is used to drive a signal amplification module with a gain of 40, amplifying the AC signal by 40 times. The amplified 800V DC voltage and the 40-fold amplified signal are then coupled between the electrostatic exciter and the sensitive element (sensing film) of the microphone.

[0025] In this embodiment, the outdoor microphone array 2 includes three microphones with self-calibration function. In use, two of the three microphones are arranged side by side to form a dual-channel microphone array, and the other is arranged inside the substation wall (if there is a physical wall). Based on this, various detection results can be obtained. For example, they include: (1) the directional anti-interference detection result SPL1 obtained by using the method described in Chinese patent application document CN114136434A; (2) the noise monitoring result SPL2 formed by using the time-frequency domain statistical difference between substation noise and interference noise as described in Chinese patent application document CN113932912A; (3) the noise monitoring result SPL3 formed by using the "sound hiding zone" technique as described in Chinese patent application document CN112504439A; (4) the noise monitoring result (SPL0) obtained without any anti-interference algorithm. Ideally, the above four results are the same. However, the results may differ when noise interference occurs from different locations and of different types. The above four results help determine whether a substation exceeds the standard. The judgment method is as follows: if min{SPL0,SPL1,SPL2,SPL3} > standard limit, it is considered exceeding the standard; if max{SPL0,SPL1,SPL2,SPL3} ≤ standard limit, it is considered compliant; in other cases, a comprehensive judgment is made considering the monitoring point location and surrounding environment. Furthermore, for convenient portable use, only one microphone can be used, with both the weather station and the microphone mounted on a telescopic pole for easy placement at the specified height. It should be noted that the monitoring results in this case only include the second and fourth types.

[0026] like Figure 1 As shown, the outdoor microphone array 2 in this embodiment consists of a telescopic rod 21, a connecting rod 22, and a windproof cover 23 connected in sequence. The microphone is installed inside the windproof cover 23, and the root of the telescopic rod 21 is fixed to the outdoor rainproof junction box 11 (or it can be fixedly installed at the boundary measuring point of the substation).

[0027] In this embodiment, the weather station 5 adopts the existing six-element compact weather station, which can collect and observe six major meteorological data such as temperature, humidity, wind speed, wind direction, atmospheric pressure, and rainfall through temperature and humidity sensors, wind sensors, pressure sensors, and humidity sensors. It can also be simplified according to actual scenarios and needs, but it should at least include wind speed and rainfall (amount).

[0028] like Figure 1As shown, the outdoor rainproof distribution box 11 in this embodiment is also equipped with a display screen 7 and a button module 8. The display screen 7 and the button module 8 are electrically connected to the circuit unit 13 installed inside the waterproof shielding shell 12, thereby meeting the user's needs for power on / off, status display, and self-calibration display during interaction. To meet the requirements of low power consumption, the display screen is not always on; it is only available for user operation and display for a few minutes (preferably 2 minutes) after power-on, and then automatically turns off after no operation. This setting meets the user's need for short-term viewing while reducing energy consumption.

[0029] like Figure 1 As shown, in this embodiment, an external solar panel 9 is also installed on the outdoor rainproof junction box 11. The solar panel 9 is electrically connected to the circuit unit 13 installed inside the waterproof shielding shell 12, and is used to power the circuit unit 13 and charge the battery pack 6 for long-term monitoring. Simultaneously, the circuit unit 13 can also use an external power adapter to charge the battery pack 6. The solar panel 9 is optional and is used for long-term (e.g., multiple months) monitoring.

[0030] To achieve long-term, interference-resistant monitoring of substation boundary noise in the presence of external noise interference, while also meeting the requirements of portability and long endurance, the noise online monitoring device for power facilities in this embodiment employs a working mechanism design and low-power control strategy to achieve long endurance. Combining the noise monitoring needs of power facilities such as substations, the device's low-power design is achieved through hardware selection optimization, working mechanism design, and energy management strategies. Furthermore, multiple microphones are used to simultaneously deploy various anti-interference algorithms, thereby achieving long endurance and interference-resistant monitoring. Specifically, this embodiment also provides an application method for the aforementioned noise online monitoring device for power facilities, including the following steps: S101, the working state of the circuit unit 13 is controlled by the hardware timer in the circuit unit 13 based on the set start time period. If the current time is within the set start time period, the circuit unit 13 is started and the process jumps to step S102; if the current time is outside the start time period, the circuit unit 13 is put into sleep or turned off and the process jumps to step S101. S102 uses an intermittent strategy to perform online noise detection of power facilities at a preset detection cycle.

[0031] Given the generally stable noise levels of substations, and the fact that noise limits are typically 10 dB(A) higher during the day than at night, it can be assumed that if the noise level measured at night does not exceed the limit, the daytime noise level will not exceed it either. Therefore, a method can be adopted where the device is activated only during a set activation period at night, and then shut down or sleeps at other times. This significantly reduces the energy consumption of the online noise monitoring device. The default activation period is 10:00 PM to 6:00 AM. Activating only during this period and then shutting down or sleeping at other times reduces energy consumption by 66% compared to continuous 24-hour operation. Furthermore, by using an intermittent strategy with a preset detection cycle for online noise monitoring of power facilities, such as running for 1 minute out of every 10 minutes, power consumption can be reduced by up to 90%.

[0032] As a preferred implementation, considering the differences in substation environments and the influence of factors such as seasons and holidays, to improve the accuracy of the start-up time period setting, a machine learning model can be trained by collecting data from different substations. This model is trained based on meteorological data collected from meteorological station 5 and time information from the collection time, including whether it is a holiday, weekday, month, and date (part or all of these). This allows for the periodic updating of the start-up time period setting in the online noise monitoring device. The presence of holidays, weekdays, months, and dates can all affect human activity patterns, such as changes in population flow and daily routines, thus impacting the noise environment of the substation. A three-layer fully connected neural network can be used, including an input layer, a hidden layer, and an output layer. The input layer has 10 neurons for inputting temperature, humidity, wind speed, wind direction, atmospheric pressure, rainfall, and whether it is a holiday, weekday, month, and date. The output layer has 2 neurons for outputting the start and end times of the start-up time period.

[0033] In this embodiment, online noise detection of power facilities includes: S201, the processor of the control circuit unit 13 enters the energy-saving mode. In the energy-saving mode, the circuit unit 13 detects the noise signal through a designated microphone in the outdoor microphone array 2 and calculates the noise sound pressure level by integration, as well as the wind speed and rainfall measured by the weather station 5. S202, determine whether the wind speed exceeds the preset wind speed threshold or the rainfall exceeds the preset rainfall threshold. If it does, the meteorological conditions are not met and the test ends. Otherwise, determine whether the noise sound pressure level exceeds the preset threshold. If the noise sound pressure level does not exceed the preset threshold, the test ends. If the noise sound pressure level exceeds the preset threshold, proceed to step S203. S203, the processor of the control circuit unit 13 enters the normal mode, and the circuit unit 13 collects noise data through multiple microphones in the outdoor microphone array 2 in the normal mode. S204, determine whether the communication signal strength of the communication and GPS modules in circuit unit 13 meets the requirements. If it does, send the collected noise data to the remote server. If there is unsent noise data in the local cache, send the cached noise data to the remote server as well. Otherwise, cache the noise data locally, such as in various non-volatile or volatile memory. In particular, storing it in non-volatile memory can ensure that the data is not lost. In addition, the communication signal strength of the communication and GPS modules in circuit unit 13 can be checked periodically. If it does, send the cached noise data to the remote server as well. S205, the remote server uses multiple preset microphone array-based noise detection algorithms to obtain noise detection results from the noise data collected by multiple microphones. If the minimum value of all noise detection results is greater than the preset standard limit, the substation is determined to have excessive noise; if the maximum value of all noise detection results is less than or equal to the preset standard limit, the substation is determined to have compliant noise.

[0034] This embodiment provides a novel approach to designing long-term stable noise monitoring devices, achieving a balance between accuracy, stability, battery life, and performance. This method is particularly suitable for noise monitoring at the boundaries of substations and converter stations, improving the efficiency of environmental noise monitoring in power facilities. Through hardware selection optimization, intermittent operation mechanism design, efficient power management, and data transmission strategy optimization, this embodiment constructs a low-power online noise monitoring solution suitable for substations, addressing the pain points of traditional devices such as limited functionality, poor battery life, and inconvenience. While ensuring monitoring accuracy, the online noise monitoring device significantly reduces overall power consumption and extends battery life, adapting to various monitoring scenarios. It possesses high practical value and promising prospects for widespread application in the field of environmental noise online monitoring, providing data support for noise pollution control.

[0035] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principle of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A noise online monitoring device for power facilities, characterized in that, The system includes a main unit (1) and an outdoor microphone array (2). The main unit (1) includes an outdoor rainproof junction box (11), a waterproof shielding shell (12), and a circuit unit (13). The waterproof shielding shell (12) is installed inside the outdoor rainproof junction box (11), and the circuit unit (13) is installed inside the waterproof shielding shell (12). The outdoor rainproof junction box (11) is equipped with a GPS antenna (3), a communication antenna (4), and a weather station (5). The outdoor rainproof junction box (11) is equipped with a battery pack (6). The outdoor microphone array (2) is installed and fixed on the outdoor rainproof junction box (11) or fixedly installed at the boundary measurement point of the substation. The outdoor microphone array (2) includes multiple microphones with self-calibration function. The microphones, GPS antenna (3), communication antenna (4), weather station (5), and battery pack (6) are connected to the circuit unit (13).

2. The noise online monitoring device for power facilities according to claim 1, characterized in that, The circuit unit (13) includes a processor, a communication and GPS module, an RS485 transceiver, a power management circuit, and a sound acquisition circuit corresponding to each microphone. The processor is connected to the communication and GPS module, the RS485 transceiver, the power management circuit, and the sound acquisition circuit, respectively. The microphone is connected to the sound acquisition circuit. The GPS antenna (3) and the communication antenna (4) are connected to the communication and GPS module, respectively. The weather station (5) is connected to the RS485 transceiver. The battery pack (6) is connected to the power management circuit to supply power to the circuit unit (13).

3. The noise online monitoring device for power facilities according to claim 2, characterized in that, The sound acquisition circuit includes a constant current source, a signal conditioning circuit, an analog-to-digital converter (ADC), and a self-calibration component. The power management circuit supplies power to the microphone through the constant current source. The output terminal of the microphone is connected in sequence through the signal conditioning circuit, the ADC, and the input terminal of the processor. The control terminal of the microphone is connected to the output terminal of the processor through the self-calibration component.

4. The noise online monitoring device for power facilities according to claim 3, characterized in that, The self-calibration component includes a DC-DC module, a filter, a DC amplification module, a signal generator, an AC amplification module, and an electrostatic exciter. The output of the DC-DC module forms a DC bias voltage on the electrostatic exciter through the filter and the DC amplification module in sequence. The control terminal of the signal generator is connected to the output terminal of the processor. The output terminal of the signal generator is connected to the electrostatic exciter through the DC amplification module and the AC amplification module respectively to generate a calibration excitation signal. The electrostatic exciter and the sensitive element of the microphone form two electrodes in a capacitor.

5. The noise online monitoring device for power facilities according to claim 4, characterized in that, The electrostatic exciter is a circular metal plate with holes or a grid.

6. The noise online monitoring device for power facilities according to claim 1, characterized in that, The outdoor microphone array (2) consists of a telescopic rod (21), a connecting rod (22), and a windproof cover (23) connected in sequence. The microphone is installed inside the windproof cover (23). The root of the telescopic rod (21) is fixed on the outdoor rainproof junction box (11) or fixedly installed at the boundary measuring point of the substation.

7. The noise online monitoring device for power facilities according to claim 1, characterized in that, The outdoor rainproof junction box (11) is also equipped with a display screen (7) and a button module (8), which are electrically connected to the circuit unit (13) installed in the waterproof shielding shell (12).

8. The noise online monitoring device for power facilities according to claim 1, characterized in that, The outdoor rainproof junction box (11) is also externally equipped with a solar cell array (9), which is electrically connected to the circuit unit (13) installed in the waterproof shielding shell (12) to supply power to the circuit unit (13) and charge the battery pack (6) for long-term monitoring.

9. A method for applying the online noise monitoring device for power facilities as described in any one of claims 1 to 8, characterized in that, Includes the following steps: S101, the working state of the circuit unit (13) is controlled by the hardware timer in the circuit unit (13) based on the set start time period. If the current time is within the set start time period, the circuit unit (13) is started and the process jumps to step S102; if the current time is outside the start time period, the circuit unit (13) is put into sleep or turned off and the process jumps to step S101. S102 uses an intermittent strategy to perform online noise detection of power facilities at a preset detection cycle.

10. The application method of the noise online monitoring device for power facilities according to claim 9, characterized in that, The online noise detection of power facilities includes: S201, the processor of the control circuit unit (13) enters the energy-saving mode. In the energy-saving mode, the circuit unit (13) detects the noise signal and calculates the noise sound pressure level by integrating one of the designated microphones in the outdoor microphone array (2), as well as the wind speed and rainfall measured by the weather station (5). S202, determine whether the wind speed exceeds the preset wind speed threshold or the rainfall exceeds the preset rainfall threshold. If it does, the meteorological conditions are not met and the test ends. Otherwise, determine whether the noise sound pressure level exceeds the preset threshold. If the noise sound pressure level does not exceed the preset threshold, the test ends. If the noise sound pressure level exceeds the preset threshold, proceed to step S203. S203, the processor of the control circuit unit (13) enters the normal mode, and the circuit unit (13) collects noise data through multiple microphones in the outdoor microphone array (2) in the normal mode. S204, determine whether the communication signal strength of the communication and GPS modules in the circuit unit (13) meets the requirements. If it meets the requirements, send the collected noise data to the remote server. If there is unsent noise data in the local cache, send the cached noise data to the remote server together; otherwise, cache the noise data locally. S205, the remote server uses multiple preset microphone array-based noise detection algorithms to obtain noise detection results from the noise data collected by multiple microphones. If the minimum value of all noise detection results is greater than the preset standard limit, the substation is determined to have excessive noise; if the maximum value of all noise detection results is less than or equal to the preset standard limit, the substation is determined to have compliant noise.

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