A tunnel lighting device powered by direct current photovoltaic and implementation method

Abstract

The application discloses a tunnel lighting device and a realization method of direct-current photovoltaic power supply, comprising a plurality of tunnel lighting systems, each of which works independently, and each of which is assigned with a unique address number according to different areas of the tunnel; each of the tunnel lighting systems comprises an MCU unit and a power unit, the power unit comprises a photovoltaic power generation panel, the photovoltaic power generation panel is connected with a voltage transformation and stabilization module, and the power supply supplies power to each unit after the voltage transformation and stabilization module; the MCU unit is connected with a sound wave detection unit, an infrared communication unit, an LED constant current dimming unit, a storage medium and an illumination sensing unit, the LED constant current dimming unit is connected with an LED lamp, and an illumination curve is stored in the storage medium. The application has the following advantages: a low-cost cluster infrared communication mode is adopted, the shortcomings of short infrared transmission distance and strong transmission directivity are overcome, a problematic node is automatically isolated, and a communication interruption problem does not occur.

Description

Technical Field

[0001] This invention relates to a DC photovoltaic-powered tunnel lighting device and its implementation method, belonging to the technical field of tunnel lighting systems. Background Technology

[0002] Tunnels are a crucial component of transportation infrastructure, playing a vital role, especially in the construction of underground spaces in mountainous areas and cities. Tunnels shorten distances, avoid steep gradients, improve traffic efficiency, and are of great significance to urban development and transportation.

[0003] The main challenge facing tunnel lighting systems today is how to maximize energy conservation, emission reduction, and economic benefits while ensuring tunnel lighting performance and safe driving.

[0004] The characteristic of tunnel lighting is that it is bright during the day and dark at night, so that the illuminance inside and outside the tunnel is similar, and drivers will not experience visual discomfort when entering and exiting the tunnel. The better the sunlight during the day, the higher the illuminance inside the tunnel, and the greater the energy consumption. However, daytime is also the peak period for photovoltaic power generation. Using photovoltaic power generation for tunnel lighting has huge economic and social benefits. At night, the energy consumption is relatively low, and the electricity generated and stored during the day can be utilized.

[0005] To avoid driving safety hazards caused by sudden changes in light and darkness when drivers enter and exit tunnels, and to prevent visual fatigue from prolonged driving inside tunnels, high requirements are placed on tunnel lighting performance. At different sections of the tunnel, the illuminance must be dynamically adjusted according to the external illuminance, with a gradual change in illuminance from the tunnel entrance, transition section, middle section, to the exit section. In the absence of traffic, the illuminance should be reduced or even turned off to achieve energy conservation and extend the lifespan of the lighting equipment.

[0006] With the upgrading of tunnel lighting technology, the past manual adjustment of illuminance has gradually shifted to automation. Emerging technologies include wired communication methods such as LAN and RS485, and wireless communication methods such as 2.4G wireless network and Bluetooth, to adjust the illuminance of tunnel lighting. Traffic flow is generally detected by using geomagnetic sensors, lidar, etc., and traffic flow information is sent to the base station information center through the Internet of Things, and then the base station controls the switching on and off of tunnel lighting.

[0007] Existing illuminance adjustment technologies require the transmission of massive amounts of data over a network to adjust the parameters of each lamp in real time. This necessitates complex communication equipment. Wired communication methods, such as LAN and RS485, require the laying of wired communication cables and the installation of relay communication equipment, resulting in high costs and complicated maintenance. If a communication cable malfunctions, tunnel lighting will become uncontrollable. Wireless communication methods, such as 2.4G and Bluetooth, are prone to interference and disconnections. Reconnection after a disconnection takes a long time, often resulting in adjustment delays and lags in response, which are detrimental to driving safety.

[0008] Existing technologies for traffic flow control, such as magnetic sensors and lidar, rely on IoT communication. However, these methods are not only costly and cannot be installed at high densities, but also suffer from network outages, control delays, and potential driving safety hazards. While infrared data transmission is a low-cost communication technology, its short transmission distance (typically a few meters) and strong directionality (requiring both transmitter and receiver to be aligned) make it difficult to apply in tunnel traffic.

[0009] To address the above issues, sound waves generated during vehicle traffic in tunnels can be used to directly detect traffic flow and trigger lighting equipment. This can reduce costs and avoid disconnection without needing a network connection. However, the environment in tunnels is complex, and various noises such as wind noise and thunder can interfere with the sound waves of traffic flow, causing traffic flow to be undetectable or to be falsely triggered when there is no traffic flow. Summary of the Invention

[0010] The technical problem this invention aims to solve is to address the above-mentioned shortcomings by providing a DC photovoltaic-powered tunnel lighting device. This device uses acoustic wave detection to identify vehicles entering the tunnel, recognizing specific frequencies of traffic to overcome environmental noise interference and accurately determine traffic flow information. For tunnel communication, it employs a low-cost cluster infrared communication method, overcoming the shortcomings of short infrared transmission distance and strong directivity, and automatically isolating problematic nodes to prevent communication interruptions. Furthermore, it uses a pre-storage medium to store a large amount of repetitive information in each lighting unit, avoiding time delays caused by massive information interaction.

[0011] To solve the above technical problems, the present invention adopts the following technical solution:

[0012] A DC photovoltaic-powered tunnel lighting device includes several tunnel lighting systems, each of which operates independently and is assigned a unique address number depending on the area in which it is installed in the tunnel.

[0013] Each tunnel lighting system includes an MCU unit and a power supply unit. The power supply unit includes a photovoltaic panel, which is connected to a transformer and voltage regulator module. The power supply is then used to power each unit after passing through the transformer and voltage regulator module. The MCU unit is connected to an acoustic detection unit, an infrared communication unit, an LED constant current dimming unit, a storage medium, and an illuminance sensing unit. The LED constant current dimming unit is connected to an LED lamp, and the illuminance curve is stored in the storage medium.

[0014] The illuminance sensing unit is installed below the LED light to detect and provide feedback on the illuminance of the tunnel lighting system.

[0015] The infrared communication unit can receive and send data. The adjacent tunnel lighting systems are installed close together. One infrared communication unit can communicate with multiple infrared communication units at the same time. When one of them fails, it can bypass the faulty infrared communication unit and communicate without affecting the infrared communication of the entire tunnel.

[0016] The tunnel lighting device also includes a lux meter, which is installed outside the tunnel and transmits the tunnel external illuminance information sequentially to each tunnel lighting system via an infrared communication unit. Each tunnel lighting system retrieves its own storage medium illuminance adjustment curve and adjusts its own illuminance according to the tunnel external illuminance.

[0017] Furthermore, the acoustic wave detection unit includes a transistor Q1. The base of transistor Q1 is connected to one end of resistor R2 and one end of capacitor C1. The other end of resistor R2 is connected to VCC power supply. The other end of capacitor C1 is connected to one end of inductor L1. The other end of inductor L1 is connected to one end of resistor R1 and one end of low-frequency acoustic wave pickup element MIC. The other end of resistor R1 is connected to VCC power supply. The other end of low-frequency acoustic wave pickup element MIC is grounded. The emitter of transistor Q1 is grounded. The collector of transistor Q1 is connected to one end of resistor R3 and the CNT terminal of MCU unit. The other end of resistor R3 is connected to VCC power supply.

[0018] Furthermore, the infrared communication unit includes an infrared communication demodulation and receiving circuit, which includes a comparator OP1. The input terminal of the comparator OP1 is connected to one end of a capacitor C4 and one end of a variable resistor R8. The other end of the capacitor C4 is connected to the DIN terminal of the MCU unit. The non-inverting output terminal of the comparator OP1 is connected to the sliding terminal of a sliding resistor R6. One end of the other two ends of the sliding resistor R6 is grounded, and the other end is connected to one end of a capacitor C2. The other end of the capacitor C2 is connected to one end of a variable resistor R5 and the collector of a transistor Q2. The emitter of the transistor Q2 is connected to one end of a resistor R7, and the other end of the resistor R7 is grounded. The base of the transistor Q2 is connected to one end of an infrared receiver IRR. The other end of the infrared receiver IRR is connected to one end of a variable resistor R4. The other ends of the variable resistor R4 and the other end of the variable resistor R5 are connected to the VCC power supply. The inverting output terminal of the comparator OP1 is connected to one end of a capacitor C3 and the other end of a variable resistor R8. The other end of the capacitor C3 is grounded.

[0019] Furthermore, the infrared communication unit also includes an infrared communication modulation and transmission circuit, which includes a comparator OP2. The non-inverting output terminal of the comparator OP2 is connected to one end of a variable resistor R9, and the other end of the variable resistor R9 is connected to the DOUT terminal of the MCU unit. The inverting output terminal of the comparator OP2 is connected to one end of a capacitor C5 and one end of a variable resistor R10. The input terminal of the comparator OP2 is connected to the other end of a variable resistor R10 and one end of a variable resistor R11. The other end of the variable resistor R11 is connected to one end of an infrared emitting diode IRF, and the other end of the infrared emitting diode IRF is grounded.

[0020] Furthermore, the illuminance sensing unit includes resistors R12 and R13. One end of resistor R12 is connected to one end of resistor R13 and the LF terminal of the MCU unit, the other end of resistor R13 is grounded, and the other end of resistor R12 is connected to one end of photoresistor RG. The other end of photoresistor RG is connected to the VCC power supply.

[0021] A method for implementing a DC photovoltaic-powered tunnel lighting device includes the following steps:

[0022] Step S101: Use infrared trunking communication. After completion, proceed to step S102.

[0023] Step S102: Receive sound wave signals and extract sound wave signals of a specific frequency as the vehicle enters the area;

[0024] Step S103: Determine whether a vehicle approaching sound wave signal is received. If received, proceed to step S104; otherwise, proceed to step S105.

[0025] In step S105, when no acoustic signal is received, the MCU unit's CNT terminal is at a low level, the MCU unit's PWM terminal output duty cycle is 0%, the LED constant current dimming unit output power is 0, and the LED light is not lit. After completion, return to continue executing step S102.

[0026] Step S104: Receive infrared communication signals from the adjacent group's tunnel lighting system in the same row. After completion, proceed to step S106.

[0027] Step S106: Determine whether an infrared communication signal is received within the sampling time. If it is received, proceed to step S110; otherwise, proceed to step S107.

[0028] Step S107: Receive infrared communication signals from another column of the same tunnel lighting system. After completion, proceed to step S108.

[0029] Step S108: Extract the infrared communication signal from another column of the same tunnel lighting system. After completion, proceed to step S110.

[0030] Step S109: Extract the address number of the infrared communication unit fault and send the fault address number to the alarm terminal to remind it to repair in time.

[0031] Step S110, Illuminance curve management, retrieve the illuminance curve in the storage medium, extract the illuminance parameters, and proceed to step S111 after completion;

[0032] Step S111: The MCU unit generates the PWM duty cycle value according to the illuminance curve, and then proceeds to step S112.

[0033] Step S112: When the CNT terminal of the MCU unit is high, the PWM terminal of the MCU unit outputs a PWM duty cycle signal with a certain duty cycle. The LED constant current dimming unit outputs power to light up the LED. When the vehicle enters, the tunnel lighting system unit within tens of meters in front of the vehicle will light up, and the tunnel lighting system behind the vehicle will turn off after a few seconds. After completion, proceed to step S113.

[0034] Step S113: Detect the brightness of LED lights in each tunnel lighting system. Each tunnel lighting system is equipped with an illuminance sensing unit installed below the LED light to detect and provide feedback on the current illuminance of the tunnel lighting system. A photoresistor RG, resistors R12 and R13 are connected in series to form a voltage divider circuit. The MCU unit calculates the voltage based on the voltage at the illuminance feedback LF terminal. When the photoresistor RG is illuminated, its resistance will decrease as the illuminance increases. The voltage on the LF terminal of the MCU unit changes, and the MCU unit can obtain the illuminance of its own LED. After completion, it proceeds to step S114.

[0035] Step S114: Determine whether the illuminance is qualified. If it is qualified, continue to step S112; otherwise, proceed to step S115.

[0036] Step S115: When the illuminance does not meet the requirements, the voltage on the LF terminal of the MCU unit will also deviate. The MCU unit obtains the illuminance deviation value, adjusts the PWM duty cycle, and adjusts the output power of the LED constant current dimming unit to make the illuminance of the LED lamps in the tunnel lighting system meet the requirements. After completion, proceed to step S116.

[0037] Step S116: Determine whether the illuminance is lower than the threshold. If it is not lower than the threshold, return to step S112. If it is lower than the threshold, proceed to step S117.

[0038] Step S117: The LED lights of the tunnel lighting system send the tunnel lighting system address number to the fault terminal.

[0039] Furthermore, the specific steps of the infrared trunking communication are as follows:

[0040] Each tunnel lighting system is equipped with an infrared communication demodulation receiving circuit on the left and an infrared communication modulation transmitting circuit on the right. The infrared receiving circuit receives information sent by the adjacent tunnel lighting system on the left, and the infrared transmitting circuit sends information to the adjacent tunnel lighting system on the right.

[0041] To avoid communication interruption due to the failure of a single infrared communication unit, the tunnel lighting system adopts a double-row installation method, with each unit installed in different areas from the tunnel entrance to the tunnel exit according to a unique address number. The address numbering adopts a row number + column number format.

[0042] The second group of tunnel lighting systems receives infrared data from the first group of tunnel lighting systems, sends it to the third group of tunnel lighting systems, and then continues to send it to the next group of tunnel lighting systems until all tunnel lighting systems in the tunnel can receive infrared data. Each pair of parallel tunnel lighting systems in each group can communicate with any one of the two tunnel lighting systems in the adjacent group. In this way, if a tunnel lighting system experiences a communication failure, the other tunnel lighting system can continue to work and send the address number of the failure to the alarm terminal to remind it to repair it in time.

[0043] A lux meter is installed outside the tunnel to detect the illuminance outside the tunnel. During each sampling time, the illuminance data outside the tunnel is sent to the first group of tunnel lighting systems at the tunnel entrance through an infrared communication unit. The first group of tunnel lighting systems receives the data and simultaneously sends the illuminance data outside the tunnel to the second group of tunnel lighting systems, and so on. All tunnel lighting systems inside the tunnel acquire the illuminance data outside the tunnel within a few seconds.

[0044] After acquiring the external illuminance data of the tunnel, the MCU unit retrieves the illuminance curve from its local storage medium, generates a PWM duty cycle, and connects it to the LED constant current dimming unit through the PWM terminal to adjust the illuminance of the LED lamp.

[0045] Furthermore, the specific communication process of the infrared communication unit in the infrared trunking communication is as follows:

[0046] The variable resistor R4 and the infrared receiver tube IRR are connected in series to provide the base signal current for the transistor Q2. The infrared receiver tube IRR receives the infrared communication signal. When there is no infrared light, the infrared receiver tube IRR is in a high-impedance state, the base current of the transistor Q2 is very small, the transistor Q2 works in the cutoff region, the collector of the transistor Q2 is at a high level, the high level is coupled through the capacitor C2, the voltage is divided by the sliding resistor R6, and the non-inverting input of the comparator OP1 is at a high level.

[0047] When infrared light shines on the transistor, the resistance of the infrared receiver tube IRR decreases significantly, the base current of transistor Q2 increases, transistor Q2 operates in the saturation region, the collector and emitter of transistor Q2 are turned on, and the voltage is pulled low through resistor R7. The collector of transistor Q2 becomes low level, and the low level is coupled through capacitor C2. The voltage is divided by sliding resistor R6, and the non-inverting input of comparator OP1 is low level.

[0048] Infrared light from a 38kHz frequency infrared pulse shines onto the infrared receiver tube IRR. The high and low levels at the non-inverting input of comparator OP1 change with the sign of the infrared pulse. Comparator OP1, capacitor C3, and variable resistor R8 form an inverting demodulator, which demodulates the signal by reversing the phase to meet the signal phase requirements of the communication system. The output of comparator OP1 is connected to the DIN terminal of the MCU unit. The high and low level changes correspond to the digital signal being decoded by the MCU unit.

[0049] The MCU unit outputs a digital signal pulse from its DOUT terminal. The high and low levels of the pulse are limited by the variable resistor R9 and applied to the non-inverting input of comparator OP2. Comparator OP2, capacitor C5, and variable resistor R11 form an inverting modulator. After the pulse signal at the non-inverting input of comparator OP2 is inverted, it is current-limited at the output of comparator OP2 by the variable resistor R11. The infrared emitting diode IRF lights up when the level is high and turns off when the level is low. Through the switching of high and low levels, the infrared emitting diode IRF emits a digital signal encoded by the MCU unit.

[0050] Furthermore, in step S102, receiving the sound wave signal and extracting the sound wave signal of the vehicle entering a specific frequency, the specific steps are as follows:

[0051] The low-frequency sound wave pickup element MIC is a unidirectional microphone, and its sensing sound wave direction is towards the vehicle's driving direction. Resistor R1 is a power supply bias resistor.

[0052] When no vehicle enters, the low-frequency acoustic wave pickup element MIC has no acoustic wave signal and is in a high-impedance state. Capacitor C1 is charged through resistor R2 and the low-frequency acoustic wave pickup element MIC, providing a saturated base voltage to transistor Q1. Transistor Q1 is in a saturated conduction state, and the collector and emitter of transistor Q1 are connected. The collector of transistor Q1 is at a low level, and the CNT terminal of the MCU unit is at a low level. Resistor R3 is a current-limiting resistor, which limits the collector saturation current of transistor Q1 to not exceed the rated current of transistor Q1.

[0053] When a vehicle enters, the low-frequency sound wave pickup element MIC picks up a sound wave signal of sufficient intensity and converts it into an electrical signal of the same frequency. Inductor L1 and capacitor C1 are connected in series to form a low-pass / band-pass filter circuit. According to the low-pass filter formula... By properly setting the values ​​of inductor L1 and capacitor C1, only low-frequency electrical signals between 150Hz and 180Hz can pass through, while electrical signals below 150Hz and above 180Hz are blocked. Electrical signals below 150Hz are isolated by capacitor C1, and electrical signals above 180Hz are blocked by inductor L1. The electrical signal couples into the base of transistor Q1, and its negative half-cycle signal causes transistor Q1 to exit the saturation region and be cut off. The collector and emitter of transistor Q1 are connected in a high-impedance state, and the collector of transistor Q1 is at a high level. The CNT terminal of the MCU unit is at a high level.

[0054] When the vehicle drives away, the sound wave signal weakens and disappears, and capacitor C1 is recharged. After a period of time, the length of time is determined by resistor R2 and capacitor C1. The larger the product of the two, the longer the time. The base voltage of transistor Q1 rises and it operates in saturation conduction state. The collector and emitter of transistor Q1 are connected, and the collector of transistor Q1 is at a low level. The CNT terminal of the MCU unit becomes low level again.

[0055] Furthermore, the illuminance curve management in step S110 is specifically as follows:

[0056] Each tunnel lighting system is assigned a unique address number based on the area it is installed in within the tunnel. Each system is equipped with a storage medium that stores the illuminance curve data and card number of the current tunnel lighting system. Through the one-to-one correspondence between the card number and the address number, data can be exchanged with the MCU unit of the current tunnel lighting system, and the illuminance of the current tunnel lighting system can be adjusted through the LED constant current dimming unit.

[0057] The illuminance curves of tunnel lighting systems installed in different areas are different. Each tunnel lighting system distributed in different areas has a unique illuminance curve. The illuminance curve is pre-written with data through a storage medium and interacts with the MCU unit. The illuminance of the current tunnel lighting system is adjusted by the LED constant current dimming unit. When the illuminance outside the tunnel changes, the illuminance data outside the tunnel is transmitted to each tunnel lighting system through the infrared communication unit. Based on their respective illuminance curves, each tunnel lighting system adjusts the LED luminous power to emit the required illuminance.

[0058] The present invention adopts the above technical solution and has the following technical effects compared with the prior art:

[0059] By employing acoustic detection to identify vehicles entering the tunnel, specific frequencies of vehicle traffic are identified, overcoming interference from environmental noise and accurately determining traffic flow information. For tunnel communication, a low-cost cluster infrared communication method is used, overcoming the shortcomings of short infrared transmission distance and strong transmission directionality, and automatically isolating problematic nodes to prevent communication interruptions. At the same time, a pre-storage medium is used to store a large amount of repetitive information in each lighting unit in advance, avoiding time delays caused by massive information interaction. Attached Figure Description

[0060] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. In all the drawings, similar elements or parts are generally identified by similar reference numerals. In the drawings, the elements or parts are not necessarily drawn to scale.

[0061] Figure 1 This is a circuit diagram of a DC photovoltaic-powered tunnel lighting device according to the present invention;

[0062] Figure 2 This is a schematic diagram of the layout of the tunnel lighting system in this invention;

[0063] Figure 3 This is a flowchart illustrating the implementation method of the DC photovoltaic-powered tunnel lighting device in this invention. Detailed Implementation

[0064] Examples, such as Figure 1 As shown, a DC photovoltaic-powered tunnel lighting device includes several tunnel lighting systems, each of which operates independently and is densely installed in different areas of the tunnel. It can detect sound waves generated during vehicle travel and trigger the lighting of the area tens of meters in front of the vehicle. When the vehicle passes, the lighting automatically turns off.

[0065] Each tunnel lighting system is assigned a unique address number depending on the area it is installed in in the tunnel. It is equipped with a storage medium (such as an SD card) that stores the current illuminance curve data of the tunnel lighting system in advance. It can interact with the MCU unit of the machine and adjust the illuminance of the tunnel lighting system through the LED constant current dimming unit.

[0066] Each tunnel lighting system is equipped with an illuminance sensor unit, installed below the LED lights, to detect and provide feedback on the illuminance of the tunnel lighting system.

[0067] Each tunnel lighting system unit is equipped with an infrared communication unit that can receive and send data, and exchange simple data with the infrared communication units of adjacent tunnel lighting systems. When there is a fault, such as a light not turning on, the faulty light number can be transmitted sequentially to the alarm terminal outside the tunnel through the adjacent infrared communication units, reminding the maintenance department to repair it in time, and the illuminance of the faulty light can be compensated by increasing the brightness of other adjacent lights.

[0068] An illuminance meter is installed outside the tunnel. The illuminance information outside the tunnel is transmitted sequentially to each tunnel lighting system via an infrared communication unit. Each tunnel lighting system retrieves its own storage medium (such as an SD card) illuminance adjustment curve and adjusts the illuminance of its machine according to the illuminance outside the tunnel.

[0069] Because the adjacent tunnel lighting systems are installed close together, one infrared communication unit can communicate with multiple infrared communication units simultaneously. When one of them malfunctions, communication can bypass the malfunctioning unit, and the infrared communication of the entire tunnel will not be affected. According to the number of the malfunctioning tunnel lighting system, the alarm information is transmitted to the alarm terminal outside the tunnel to remind the maintenance department to repair it in time.

[0070] Because a large amount of data is pre-stored, the data volume of the infrared communication unit is very small. It sends tunnel external illuminance information every sampling time (since outdoor illuminance does not change suddenly, the sampling time is generally set to half a minute). In addition, when there is a lamp failure, it sends a fault number to the alarm terminal. Because there is very little data interaction, low-cost infrared transmitters and receivers can be used, which is low in cost and will not drop the connection.

[0071] Each tunnel lighting system includes an MCU unit and a power supply unit. The MCU unit uses STC89 series chips, and the power supply unit includes a photovoltaic panel connected to a transformer and voltage regulator module. The power supply is then used to power each unit after passing through the transformer and voltage regulator module. The power supply unit also includes a battery connected to a charging and discharging module. The battery uses photovoltaic power supply, taking into account the characteristics of tunnel lighting. During the day, the illumination is good, and the photovoltaic power generation is sufficient to supply power for tunnel lighting and charge the battery. At night, the tunnel lighting requires less power, so the battery discharges to provide power for lighting.

[0072] The MCU unit is connected to an acoustic wave detection unit, which includes a transistor Q1. The base of transistor Q1 is connected to one end of resistor R2 and one end of capacitor C1. The other end of resistor R2 is connected to VCC power supply. The other end of capacitor C1 is connected to one end of inductor L1. The other end of inductor L1 is connected to one end of resistor R1 and one end of low-frequency acoustic wave pickup element MIC. The other end of resistor R1 is connected to VCC power supply. The other end of low-frequency acoustic wave pickup element MIC is grounded. The emitter of transistor Q1 is grounded. The collector of transistor Q1 is connected to one end of resistor R3 and the CNT terminal of the MCU unit. The other end of resistor R3 is connected to VCC power supply.

[0073] The MCU unit is connected to an infrared communication unit, which includes an infrared communication demodulation receiving circuit and an infrared communication modulation transmitting circuit. The infrared communication demodulation receiving circuit includes a comparator OP1. The input terminal of the comparator OP1 is connected to one end of a capacitor C4 and one end of a variable resistor R8. The other end of the capacitor C4 is connected to the DIN terminal of the MCU unit. The non-inverting output terminal of the comparator OP1 is connected to the sliding terminal of a sliding resistor R6. One end of the other two ends of the sliding resistor R6 is grounded, and the other end is connected to one end of a capacitor C2. The other end of the capacitor C2 is connected to one end of a variable resistor R5 and the collector of a transistor Q2. The emitter of the transistor Q2 is connected to one end of a resistor R7, and the other end of the resistor R7 is grounded. The base of the transistor Q2 is connected to one end of an infrared receiver IRR. The other end of the infrared receiver IRR is connected to one end of a variable resistor R4. The other ends of the variable resistor R4 and the other end of the variable resistor R5 are connected to the VCC power supply. The inverting output terminal of the comparator OP1 is connected to one end of a capacitor C3 and the other end of a variable resistor R8. The other end of the capacitor C3 is grounded.

[0074] The infrared communication modulation and transmission circuit includes a comparator OP2. The non-inverting output of the comparator OP2 is connected to one end of a variable resistor R9, and the other end of the variable resistor R9 is connected to the DOUT terminal of the MCU unit. The inverting output of the comparator OP2 is connected to one end of a capacitor C5 and one end of a variable resistor R10. The input of the comparator OP2 is connected to the other end of a variable resistor R10 and one end of a variable resistor R11. The other end of the variable resistor R11 is connected to one end of an infrared emitting diode IRF, and the other end of the infrared emitting diode IRF is grounded.

[0075] The PWM terminal of the MCU unit is connected to an LED constant current dimming unit, and the LED constant current dimming unit is connected to an LED lamp.

[0076] The MCU unit is connected to an illumination sensing unit, which includes resistors R12 and R13. One end of resistor R12 is connected to one end of resistor R13 and the LF terminal of the MCU unit. The other end of resistor R13 is grounded. The other end of resistor R12 is connected to one end of a photoresistor RG. The other end of photoresistor RG is connected to the VCC power supply.

[0077] The REM terminal of the MCU unit is connected to a storage medium, and the illuminance curve is stored in the storage medium.

[0078] A method for implementing a DC photovoltaic-powered tunnel lighting device includes the following steps:

[0079] Step S101: Use infrared trunking communication. After completion, proceed to step S102.

[0080] The specific steps of infrared trunking communication are as follows:

[0081] Infrared data has a short transmission distance, usually a few meters, making it difficult to transmit data in tunnels hundreds to thousands of meters long. In addition, the infrared communication receiver and transmitter must be in the same direction to receive the signal. This invention solves this problem well by using a cluster infrared communication method.

[0082] Each tunnel lighting system has an infrared communication demodulation receiving circuit installed on the left and an infrared communication modulation transmitting circuit installed on the right. The infrared receiving circuit receives information sent by the adjacent tunnel lighting system on the left, and the infrared transmitting circuit sends information to the adjacent tunnel lighting system on the right.

[0083] To avoid communication interruption due to the failure of a single infrared communication unit, the tunnel lighting system is installed in a double-row configuration. Each unit is installed in a different area from the tunnel entrance to the exit, using a unique address numbering system. The address numbers are in a row + column format, for example, 1-1, 1-2, 2-1, 2-2, 3-1, 3-2. These represent two parallel tunnel lighting systems in each of the first, second, and third groups, for a total of six systems. The second group receives infrared data from the first group and sends it to the third group, which in turn sends it to the next group, until all tunnel lighting systems can receive the infrared data. Each pair of parallel tunnel lighting systems in one group can communicate with either of the two systems in the adjacent group. This ensures that if one tunnel lighting system experiences a communication failure, the other can continue operating and send the faulty address number to the alarm terminal for timely repair.

[0084] A lux meter is installed outside the tunnel to detect the illuminance outside the tunnel. During each sampling period (generally half a minute, since the illuminance outside the tunnel does not change abruptly), the illuminance data outside the tunnel is sent to the first group of tunnel lighting systems at the tunnel entrance through an infrared communication unit. The first group of tunnel lighting systems receives the data and simultaneously sends the illuminance data outside the tunnel to the second group of tunnel lighting systems, and so on. All tunnel lighting systems inside the tunnel acquire the illuminance data outside the tunnel within a few seconds.

[0085] After acquiring the external illuminance data of the tunnel, the MCU unit retrieves the illuminance curve from its local storage medium, generates a PWM duty cycle, and connects it to the LED constant current dimming unit through the PWM terminal to adjust the illuminance of the LED lamp.

[0086] The specific communication process of the infrared communication unit is as follows:

[0087] The variable resistor R4 and the infrared receiver tube IRR are connected in series to provide the base signal current for the transistor Q2. The infrared receiver tube IRR receives the infrared communication signal. When there is no infrared light, the infrared receiver tube IRR is in a high-impedance state, the base current of the transistor Q2 is very small, the transistor Q2 works in the cutoff region, the collector of the transistor Q2 is at a high level, the high level is coupled through the capacitor C2, the voltage is divided by the sliding resistor R6, and the non-inverting input of the comparator OP1 is at a high level.

[0088] When infrared light shines on the transistor, the resistance of the infrared receiver tube IRR decreases significantly, the base current of transistor Q2 increases, and transistor Q2 operates in the saturation region. The collector and emitter of transistor Q2 are turned on, and the voltage is pulled low through resistor R7. The collector of transistor Q2 becomes low level, and the low level is coupled through capacitor C2. The voltage is divided by sliding resistor R6, and the non-inverting input of comparator OP1 becomes low level.

[0089] Infrared light from a 38kHz frequency infrared pulse shines onto the infrared receiver tube IRR. The high and low levels at the non-inverting input of comparator OP1 change with the sign of the infrared pulse. Comparator OP1, capacitor C3, and variable resistor R8 form an inverting demodulator, which demodulates the signal by reversing the phase to meet the signal phase requirements of the communication system. The output of comparator OP1 is connected to the DIN terminal of the MCU unit. The high and low level changes correspond to the digital signal being decoded by the MCU unit.

[0090] The MCU unit outputs a digital signal pulse from its DOUT terminal. The high and low levels of the pulse are limited by the variable resistor R9 and applied to the non-inverting input of comparator OP2. Comparator OP2, capacitor C5, and variable resistor R11 form an inverting modulator. After the pulse signal at the non-inverting input of comparator OP2 is inverted, it is current-limited at the output of comparator OP2 by the variable resistor R11. The infrared emitting diode IRF lights up when the level is high and turns off when the level is low. Through the switching of high and low levels, the infrared emitting diode IRF emits a digital signal encoded by the MCU unit.

[0091] Step S102: Receive the sound wave signal and extract the sound wave signal of the vehicle entering a specific frequency. The specific steps are as follows:

[0092] When a vehicle enters a tunnel, it generates sound waves ranging from 75Hz to 400Hz. Meanwhile, the frequency of tunnel wind noise is between 70Hz and 100Hz, and the frequency of lightning noise is between 250Hz and 700Hz. In order to avoid the interference of environmental noise on the sound waves of vehicles entering the tunnel, it is necessary to extract low-frequency sound waves of 150Hz to 180Hz as the traffic flow detection frequency.

[0093] The low-frequency sound wave pickup element MIC is a unidirectional microphone, and its sensed sound wave direction is towards the vehicle's driving direction. Resistor R1 is a power supply bias resistor.

[0094] When no vehicle enters, the low-frequency acoustic wave pickup element MIC has no acoustic wave signal and is in a high-impedance state. Capacitor C1 is charged through resistor R2 and the low-frequency acoustic wave pickup element MIC, providing a saturation base voltage to transistor Q1. Transistor Q1 operates in a saturated conduction state, and the collector and emitter of transistor Q1 are connected. The collector of transistor Q1 is at a low level, and the CNT terminal of the MCU unit is at a low level. Resistor R3 is a current-limiting resistor, which limits the collector saturation current of transistor Q1 from not exceeding the rated current of the transistor.

[0095] When a vehicle enters, the low-frequency sound wave pickup element MIC picks up a sound wave signal of sufficient intensity and converts it into an electrical signal of the same frequency. Inductor L1 and capacitor C1 are connected in series to form a low-pass / band-pass filter circuit. According to the low-pass filter formula... By properly setting the values ​​of L1 and C1 (e.g., C1 is set to 1000 microfarads and L1 to 200 millihenries), only low-frequency electrical signals between 150Hz and 180Hz can pass through. Electrical signals below 150Hz and above 180Hz are blocked. Electrical signals below 150Hz are isolated by capacitor C1, and electrical signals above 180Hz are blocked by inductor L1. The electrical signal couples into the base of transistor Q1, and its negative half-cycle signal causes transistor Q1 to exit the saturation region and be cut off. The collector and emitter of transistor Q1 are connected in a high-impedance state, and the collector of transistor Q1 is at a high level. The CNT terminal of the MCU unit is at a high level.

[0096] When the vehicle drives away, the sound wave signal weakens and disappears, and capacitor C1 is recharged. After a period of time (the length of time is determined by resistor R2 and capacitor C1; the larger the product of the two, the longer the time, usually a few seconds), the base voltage of transistor Q1 rises and it operates in saturation conduction state. The collector and emitter of transistor Q1 are connected, and the collector of transistor Q1 is at a low level. The CNT terminal of the MCU unit then becomes low level again.

[0097] Step S103: Determine whether a vehicle approaching sound wave signal is received. If received, proceed to step S104; otherwise, proceed to step S105.

[0098] In step S105, when no acoustic signal is received, the MCU unit's CNT terminal is at a low level, the MCU unit's PWM terminal output duty cycle is 0%, the LED constant current dimming unit output power is 0, and the LED light is not lit. After completion, return to continue executing step S102.

[0099] Step S104: Receive infrared communication signals from the adjacent group's tunnel lighting system in the same row. After completion, proceed to step S106.

[0100] Step S106: Determine whether an infrared communication signal is received within the sampling time. If it is received, proceed to step S110; otherwise, proceed to step S107.

[0101] Step S107: Receive infrared communication signals from another column of the same tunnel lighting system. After completion, proceed to step S108.

[0102] Step S108: Extract the infrared communication signal from another column of the same tunnel lighting system. After completion, proceed to step S110.

[0103] Step S109: Extract the address number of the infrared communication unit fault and send the fault address number to the alarm terminal to remind it to repair in time.

[0104] Step S110, Illuminance curve management, retrieve the illuminance curve in the storage medium, extract the illuminance parameters, and proceed to step S111 after completion;

[0105] The specific details of illuminance curve management are as follows:

[0106] Because each lamp in the tunnel is in a different position, its illuminance curve is different. There are many problems in transmitting data to hundreds or thousands of lamps through communication. Using storage media to store the illuminance curve in advance is a low-cost method, but in the implementation process, there are problems such as similar appearance and large number of lamps, which can easily lead to confusion and errors. This invention solves this problem well by using address numbering.

[0107] Each tunnel lighting system is assigned a unique address number based on the area it is installed in within the tunnel. Each system is equipped with a storage medium (such as an SD card) that stores the illuminance curve data of the current tunnel lighting system and the card number. Through the one-to-one correspondence between the card number and the address number, data can be exchanged with the MCU unit of the current tunnel lighting system, and the illuminance of the current tunnel lighting system can be adjusted through the LED constant current dimming unit.

[0108] The illuminance curves of tunnel lighting systems installed in different areas are different. For example, at the tunnel entrance, the tunnel lighting requirements are consistent with those outside the tunnel to avoid sudden changes in brightness for drivers entering the tunnel. In the center of the tunnel, during the day when the illuminance is good, the illuminance gradually decreases from the entrance to the center, while at night, the illuminance gradually increases from the entrance to the center. Therefore, each tunnel lighting system distributed in different areas has a unique illuminance curve. The illuminance curve is pre-written with data through a storage medium (such as an SD card) and interacts with the MCU unit. The illuminance of the current tunnel lighting system is adjusted by the LED constant current dimming unit. When the illuminance outside the tunnel changes, the illuminance data outside the tunnel is transmitted to each tunnel lighting system through the infrared communication unit. Based on their respective illuminance curves, each tunnel lighting system adjusts the LED luminous power to emit the required illuminance.

[0109] Step S111: The MCU unit generates the PWM duty cycle value according to the illuminance curve, and then proceeds to step S112.

[0110] Step S112: When the CNT terminal of the MCU unit is high, the PWM terminal of the MCU unit outputs a PWM duty cycle signal with a certain duty cycle. The LED constant current dimming unit outputs power to light up the LED. Therefore, when the vehicle enters, the tunnel lighting system units within tens of meters in front of the vehicle will light up, and the tunnel lighting system behind the vehicle will turn off after a few seconds. After completion, proceed to step S113.

[0111] Step S113: The photoresistor detects the brightness of the LED lights in each tunnel lighting system. Each tunnel lighting system is equipped with an illuminance sensing unit installed below the LED light to detect and provide feedback on the current illuminance of the tunnel lighting system. The photoresistor RG is connected in series with resistors R12 and R13 to form a voltage divider circuit. The MCU unit calculates the voltage based on the voltage at the illuminance feedback LF terminal. When the photoresistor RG is illuminated, its resistance will decrease as the illuminance increases. The voltage on the LF terminal of the MCU unit changes, and the MCU unit can obtain the illuminance of its own LED. After completion, it proceeds to step S114.

[0112] Step S114: Determine whether the illuminance is qualified. If it is qualified, continue to step S112; otherwise, proceed to step S115.

[0113] Step S115: When the illuminance does not meet the requirements due to some reason (such as light decay or dust), the voltage on the LF terminal of the MCU unit will also deviate. The MCU unit obtains the illuminance deviation value, adjusts the PWM duty cycle, and adjusts the output power of the LED constant current dimming unit to make the illuminance of the LED lamp in the tunnel lighting system meet the requirements. After completion, proceed to step S116.

[0114] Step S116: Determine whether the illuminance is lower than the threshold. If it is not lower than the threshold, return to step S112. If it is lower than the threshold, proceed to step S117.

[0115] Step S117: The LED lights of the tunnel lighting system send the tunnel lighting system address number to the fault terminal.

[0116] The description of this invention is given for illustrative and descriptive purposes only and is not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention and to enable those skilled in the art to understand the invention and design various embodiments with various modifications suitable for a particular purpose.

Claims

1. A DC photovoltaic-powered tunnel lighting device, characterized in that: It includes several tunnel lighting systems, each of which operates independently and is assigned a unique address number depending on the area in which it is installed in the tunnel; Each tunnel lighting system includes an MCU unit and a power supply unit. The power supply unit includes a photovoltaic panel, which is connected to a transformer and voltage regulator module. The power supply is then used to power each unit after passing through the transformer and voltage regulator module. The MCU unit is connected to an acoustic detection unit, an infrared communication unit, an LED constant current dimming unit, a storage medium, and an illuminance sensing unit. The LED constant current dimming unit is connected to an LED lamp, and the illuminance curve is stored in the storage medium. The illuminance sensing unit is installed below the LED light to detect and provide feedback on the illuminance of the tunnel lighting system. The infrared communication unit can receive and send data. The adjacent tunnel lighting systems are installed close together. One infrared communication unit can communicate with multiple infrared communication units at the same time. When one of them fails, it can bypass the faulty infrared communication unit and communicate without affecting the infrared communication of the entire tunnel. The tunnel lighting device also includes an illuminance meter, which is installed outside the tunnel. The illuminance information outside the tunnel is transmitted sequentially to each tunnel lighting system through an infrared communication unit. Each tunnel lighting system retrieves the illuminance curve stored in its own storage medium and adjusts the illuminance of the tunnel lighting system according to the illuminance outside the tunnel. Each tunnel lighting system is equipped with an infrared communication demodulation receiving circuit on the left and an infrared communication modulation transmitting circuit on the right. The infrared receiving circuit receives information sent by the adjacent tunnel lighting system on the left, and the infrared transmitting circuit sends information to the adjacent tunnel lighting system on the right. To avoid communication interruption due to the failure of a single infrared communication unit, the tunnel lighting system adopts a double-row installation method, with each unit installed in different areas from the tunnel entrance to the tunnel exit according to a unique address number. The address numbering adopts a row number + column number format. The second group of tunnel lighting systems receives infrared data from the first group of tunnel lighting systems, sends it to the third group of tunnel lighting systems, and then continues to send it to the next group of tunnel lighting systems until all tunnel lighting systems in the tunnel can receive infrared data. Each pair of parallel tunnel lighting systems in each group can communicate with any one of the two tunnel lighting systems in the adjacent group. In this way, if a tunnel lighting system experiences a communication failure, the other tunnel lighting system can continue to work and send the address number of the failure to the alarm terminal to remind it to repair it in time. An illuminance meter is installed outside the tunnel to detect the illuminance outside the tunnel. During each sampling time, the illuminance data outside the tunnel is sent to the first group of tunnel lighting systems at the tunnel entrance through an infrared communication unit. The first group of tunnel lighting systems receives the data and simultaneously sends the illuminance data outside the tunnel to the second group of tunnel lighting systems, and so on. All tunnel lighting systems inside the tunnel acquire the illuminance data outside the tunnel within a few seconds. After the tunnel lighting system acquires the external illuminance data, the MCU unit retrieves the illuminance curve stored in the storage medium of the tunnel lighting system using this data, generates the PWM duty cycle, and connects it to the LED constant current dimming unit through the PWM terminal to adjust the illuminance of the LED lamp.

2. The DC photovoltaic-powered tunnel lighting device as described in claim 1, characterized in that: The acoustic wave detection unit includes a transistor Q1. The base of transistor Q1 is connected to one end of resistor R2 and one end of capacitor C1. The other end of resistor R2 is connected to VCC power supply. The other end of capacitor C1 is connected to one end of inductor L1. The other end of inductor L1 is connected to one end of resistor R1 and one end of low-frequency acoustic wave pickup element MIC. The other end of resistor R1 is connected to VCC power supply. The other end of low-frequency acoustic wave pickup element MIC is grounded. The emitter of transistor Q1 is grounded. The collector of transistor Q1 is connected to one end of resistor R3 and the CNT terminal of MCU unit. The other end of resistor R3 is connected to VCC power supply. The low-frequency sound wave pickup element MIC is a unidirectional microphone, and its sensed sound wave direction is towards the vehicle's driving direction. Resistor R1 is a power supply bias resistor.

3. The DC photovoltaic-powered tunnel lighting device as described in claim 1, characterized in that: The infrared communication unit includes an infrared communication demodulation and receiving circuit, which includes a comparator OP1. The input terminal of the comparator OP1 is connected to one end of a capacitor C4 and one end of a variable resistor R8. The other end of the capacitor C4 is connected to the DIN terminal of the MCU unit. The non-inverting output terminal of the comparator OP1 is connected to the sliding terminal of a sliding resistor R6. One end of the other two ends of the sliding resistor R6 is grounded, and the other end is connected to one end of a capacitor C2. The other end of the capacitor C2 is connected to one end of a variable resistor R5 and the collector of a transistor Q2. The emitter of the transistor Q2 is connected to one end of a resistor R7, and the other end of the resistor R7 is grounded. The base of the transistor Q2 is connected to one end of an infrared receiver IRR. The other end of the infrared receiver IRR is connected to one end of a variable resistor R4. The other ends of the variable resistor R4 and the other end of the variable resistor R5 are connected to the VCC power supply. The inverting output terminal of the comparator OP1 is connected to one end of a capacitor C3 and the other end of a variable resistor R8. The other end of the capacitor C3 is grounded.

4. A DC photovoltaic-powered tunnel lighting device as described in claim 1, characterized in that: The infrared communication unit also includes an infrared communication modulation and transmission circuit, which includes a comparator OP2. The non-inverting output of the comparator OP2 is connected to one end of a variable resistor R9, and the other end of the variable resistor R9 is connected to the DOUT terminal of the MCU unit. The inverting output of the comparator OP2 is connected to one end of a capacitor C5 and one end of a variable resistor R10. The input of the comparator OP2 is connected to the other end of a variable resistor R10 and one end of a variable resistor R11. The other end of the variable resistor R11 is connected to one end of an infrared emitting diode IRF, and the other end of the infrared emitting diode IRF is grounded.

5. A DC photovoltaic-powered tunnel lighting device as described in claim 1, characterized in that: The illumination sensing unit includes resistors R12 and R13. One end of resistor R12 is connected to one end of resistor R13 and the LF terminal of the MCU unit. The other end of resistor R13 is grounded. The other end of resistor R12 is connected to one end of photoresistor RG. The other end of photoresistor RG is connected to the VCC power supply.

6. A method for implementing a DC photovoltaic-powered tunnel lighting device, characterized in that: The implementation method, when applied to a DC photovoltaic-powered tunnel lighting device as described in any one of claims 1-5, includes the following steps: Step S101: Use infrared trunking communication. After completion, proceed to step S102. Step S102: Receive the sound wave signal and extract the sound wave signal of the vehicle entering a specific frequency from the sound wave signal; Step S103: Determine whether a vehicle approaching sound wave signal is received. If received, proceed to step S104; otherwise, proceed to step S105. In step S105, when no acoustic signal is received, the MCU unit's CNT terminal is at a low level, the MCU unit's PWM terminal output duty cycle is 0%, the LED constant current dimming unit output power is 0, and the LED light is not lit. After completion, return to continue executing step S102. Step S104: Receive infrared communication signals from the adjacent group's tunnel lighting system in the same row; after completion, proceed to step S106. Step S106: Determine whether an infrared communication signal is received within the sampling time. If it is received, proceed to step S110; otherwise, proceed to step S107. Step S107: Receive infrared communication signals from another column of the same tunnel lighting system. After completion, proceed to step S108. Step S108: Extract the infrared communication signal from another column of the same tunnel lighting system. After completion, proceed to step S110. Step S109: Extract the address number of the infrared communication unit failure and send the address number of the failure to the alarm terminal to remind it to repair in time; Step S110, Illuminance curve management, retrieve the illuminance curve stored in the storage medium, extract the illuminance parameters, and proceed to step S111 after completion; Step S111: The MCU unit generates the PWM duty cycle value according to the illuminance curve, and then proceeds to step S112. In step S112, when the CNT terminal of the MCU unit is at a high level, the MCU unit outputs a pulse width modulation PWM signal with a specific duty cycle parameter through its PWM function terminal. The LED constant current dimming unit outputs power to light up the LED. When the vehicle enters, the tunnel lighting system unit within tens of meters in front of the vehicle will light up, and the tunnel lighting system behind the vehicle will turn off after a few seconds. After completion, proceed to step S113. Step S113: Detect the brightness of LED lights in each tunnel lighting system. Each tunnel lighting system is equipped with an illuminance sensing unit installed below the LED light to detect and provide feedback on the current illuminance of the tunnel lighting system. A photoresistor RG, resistors R12 and R13 are connected in series to form a voltage divider circuit. The MCU unit calculates the voltage based on the voltage at the illuminance feedback LF terminal. When the photoresistor RG is illuminated, its resistance will decrease as the illuminance increases. The voltage on the LF terminal of the MCU unit changes, and the MCU unit can obtain the illuminance of its own LED. After completion, it proceeds to step S114. Step S114: Determine whether the illuminance is qualified. If it is qualified, continue to step S112; otherwise, proceed to step S115. Step S115: When the illuminance does not meet the requirements, the voltage on the LF terminal of the MCU unit will also deviate. The MCU unit obtains the illuminance deviation value, adjusts the PWM duty cycle, and adjusts the output power of the LED constant current dimming unit to make the illuminance of the LED lamps in the tunnel lighting system meet the requirements. After completion, proceed to step S116. Step S116: Determine whether the illuminance is lower than the threshold. If it is not lower than the threshold, return to step S112. If it is lower than the threshold, proceed to step S117. Step S117: The LED lights of the tunnel lighting system send the tunnel lighting system address number to the fault terminal.

7. The method for implementing a DC photovoltaic-powered tunnel lighting device as described in claim 6, characterized in that: The specific communication process of the infrared communication unit in the infrared trunking communication is as follows: The variable resistor R4 and the infrared receiver tube IRR are connected in series to provide the base signal current for the transistor Q2. The infrared receiver tube IRR receives the infrared communication signal. When there is no infrared light, the infrared receiver tube IRR is in a high-impedance state, the base current of the transistor Q2 is very small, the transistor Q2 works in the cutoff region, the collector of the transistor Q2 is at a high level, the high level is coupled through the capacitor C2, the voltage is divided by the sliding resistor R6, and the non-inverting input of the comparator OP1 is at a high level. When infrared light shines on the transistor, the resistance of the infrared receiver tube IRR decreases significantly, the base current of transistor Q2 increases, transistor Q2 operates in the saturation region, the collector and emitter of transistor Q2 are turned on, and the voltage is pulled low through resistor R7. The collector of transistor Q2 becomes low level, and the low level is coupled through capacitor C2. The voltage is divided by sliding resistor R6, and the non-inverting input of comparator OP1 is low level. Infrared light from a 38kHz frequency infrared pulse shines onto the infrared receiver tube IRR. The high and low levels at the non-inverting input of comparator OP1 change with the sign of the infrared pulse. Comparator OP1, capacitor C3, and variable resistor R8 form an inverting demodulator, which demodulates the signal by reversing the phase to meet the signal phase requirements of the communication system. The output of comparator OP1 is connected to the DIN terminal of the MCU unit. The high and low level changes correspond to the digital signal being decoded by the MCU unit. The MCU unit outputs a digital signal pulse from its DOUT terminal. The high and low levels of the pulse are limited by the variable resistor R9 and applied to the non-inverting input of comparator OP2. Comparator OP2, capacitor C5, and variable resistor R11 form an inverting modulator. After the pulse signal at the non-inverting input of comparator OP2 is inverted, it is current-limited at the output of comparator OP2 by the variable resistor R11. The infrared emitting diode IRF lights up when the level is high and turns off when the level is low. Through the switching of high and low levels, the infrared emitting diode IRF emits a digital signal encoded by the MCU unit.

8. The method for implementing a DC photovoltaic-powered tunnel lighting device as described in claim 6, characterized in that: In step S102, the sound wave signal is received, and the sound wave signal of the vehicle entering a specific frequency is extracted from the sound wave signal. The specific steps are as follows: When no vehicle enters, the low-frequency acoustic wave pickup element MIC has no acoustic wave signal and is in a high-impedance state. Capacitor C1 is charged through resistor R2 and the low-frequency acoustic wave pickup element MIC, providing a saturated base voltage to transistor Q1. Transistor Q1 is in a saturated conduction state, and the collector and emitter of transistor Q1 are connected. The collector of transistor Q1 is at a low level, and the CNT terminal of the MCU unit is at a low level. Resistor R3 is a current-limiting resistor, which limits the collector saturation current of transistor Q1 to not exceed the rated current of transistor Q1. When the vehicle enters, the low-frequency sound wave pickup element MIC picks up a sound wave signal of sufficient intensity and converts it into an electrical signal of the same frequency. Inductor L1 and capacitor C1 are connected in series to form a bandpass filter circuit. According to the low-pass filter formula... By properly setting the values ​​of inductor L1 and capacitor C1, only low-frequency electrical signals between 150Hz and 180Hz can pass through, while electrical signals below 150Hz and above 180Hz are blocked. Electrical signals below 150Hz are isolated by capacitor C1, and electrical signals above 180Hz are blocked by inductor L1. The electrical signal couples into the base of transistor Q1, and its negative half-cycle signal causes transistor Q1 to exit the saturation region and be cut off. The collector and emitter of transistor Q1 are connected in a high-impedance state, and the collector of transistor Q1 is at a high level. The CNT terminal of the MCU unit is at a high level. When the vehicle drives away, the sound wave signal weakens and disappears, and capacitor C1 is recharged. After a period of time, the length of time is determined by resistor R2 and capacitor C1. The larger the product of the two, the longer the time. The base voltage of transistor Q1 rises and it operates in saturation conduction state. The collector and emitter of transistor Q1 are connected, and the collector of transistor Q1 is at a low level. The CNT terminal of the MCU unit becomes low level again.

9. The method for implementing a DC photovoltaic-powered tunnel lighting device as described in claim 6, characterized in that: The illuminance curve management in step S110 is as follows: Each tunnel lighting system is assigned a unique address number based on its installation area within the tunnel. Each system is equipped with a storage medium containing the current illuminance curve data and a card number. The MCU unit interacts with the storage medium through the one-to-one correspondence between the card number and the address number, adjusting the illuminance of the current tunnel lighting system via the LED constant current dimming unit. The illuminance curves of tunnel lighting systems installed in different areas are different, and each system in its respective area has a unique illuminance curve. This curve is pre-written into the storage medium and interacts with the MCU unit, adjusting the illuminance of the current tunnel lighting system via the LED constant current dimming unit. When the external illuminance changes, the external illuminance data is transmitted to each tunnel lighting system via an infrared communication unit. Based on their respective illuminance curves, each tunnel lighting system adjusts its LED power to emit the required illuminance.

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