Intelligent lamp control sensor based on GMI and application thereof

Abstract

The invention relates to the technical field of magnetic sensors, and discloses a GMI-based intelligent lamp control sensor and application thereof, and the sensor comprises an excitation signal module, a GMI module, a signal processing module, a microcontroller module, an LED lamp module and a power management module which are in circuit connection. The GMI module detects the impedance change of the amorphous wire caused by the change of an external magnetic field and converts the impedance change into an induced voltage signal under the driving of the received high-frequency excitation signal of the excitation signal module; the signal is amplified and filtered by the signal processing module and is converted into a digital signal representing the external magnetic field intensity by the microcontroller module, and the brightness of an intelligent lamp in the LED lamp module is adjusted according to a preset threshold value; the intelligent LED lamp control system has the advantages of high efficiency, low power consumption and anti-interference capability, and is suitable for intelligent illumination management of modern underground parking lots.

Description

Technical Field

[0001] The present invention relates to the technical field of magnetic sensors, and in particular to a GMI-based intelligent lighting control sensor and applications thereof. Background Art

[0002] Underground parking lots have become key facilities to ease urban traffic congestion and parking problems. Among them, the lighting system, as a core component of underground parking lots, is not only related to the safety of car owners and the parking experience, but also directly affects energy consumption and operating costs. However, there are some obvious problems with the traditional underground parking lot lighting system: First, the lighting system is often kept at full brightness, regardless of whether there are vehicles entering or leaving the parking lot, which will cause a lot of energy waste. Even during idle periods in the parking lot, the lighting brightness is still very high and cannot be adjusted on demand. Secondly, most of the existing lighting systems rely on time switches or simple sensor control, and cannot be intelligently adjusted according to the real-time vehicle flow in the parking lot. Therefore, when the vehicle flow is low, the lighting system still maintains a high brightness, resulting in energy waste. In addition, the traditional lighting system lacks the ability to respond immediately to environmental changes in the parking lot, and cannot effectively respond to sudden parking needs or idle conditions, thereby exacerbating energy consumption and operating costs.

[0003] In order to solve these problems, intelligent lighting technology has become an important solution for underground parking lot lighting systems in recent years and has made significant progress. By integrating intelligent components such as sensors and controllers, the system can sense changes in vehicles, people, sounds, etc. in the parking lot in real time, and automatically adjust the brightness of the lights to achieve more efficient and energy-saving lighting management. However, although these sensors (such as infrared, ultrasonic, voice control, etc.) can detect the presence of people or vehicles, they usually have problems such as poor environmental adaptability, low sensitivity, and poor anti-interference ability. In a complex environment such as a parking lot, factors such as vehicle movement, light changes, noise interference, and the accuracy of sound signal recognition will interfere with the accuracy and stability of the sensor, resulting in slow or erroneous system response, and unable to achieve the expected energy-saving and intelligent control effects.

[0004] Publication No. CN107295720A discloses an intelligent light dimming device, system and method. The system collects and sends infrared image data through an infrared image acquisition module, and is automatically controlled by a main control module to adjust the brightness and color of the light. However, the device may be affected by changes in ambient temperature, obstacles or strong light sources, resulting in reduced accuracy and reliability of data collection, and is not suitable for use in complex environments such as underground parking lots.

[0005] Publication No. CN105007648A discloses a voice-controlled lamp intelligent control device, which collects signals from a sound sensor and a human proximity sensor at the same time to ensure that the light will only turn on when a person passes by. However, the recognition accuracy of the sound sensor still needs attention, and false triggering or failure to trigger may occur, thus affecting the accuracy of light control.

[0006] Publication number CN216600155U discloses an intelligent classroom lighting control system based on ultrasonic sensors. The system intelligently controls the lighting device according to the changes in light intensity inside and outside the classroom and the entry and exit of people, thereby reducing power waste. It has the advantages of intelligent energy saving, improved convenience and reduced operating costs, and is suitable for environments with large traffic (such as classrooms, offices, etc.). However, when used in underground parking lots, ultrasonic sensors are easily affected by factors such as environmental noise and object interference, which may cause false triggering or missed triggering. Summary of the invention

[0007] In order to solve the problems of weak anti-interference ability and low sensitivity of traditional sensors, the present invention provides an intelligent lighting control sensor for underground parking lots based on GMI, which can automatically adjust the brightness of lights in the parking lot according to the approach / distance of the sensed object. It is an efficient, low-power and anti-interference intelligent lighting control solution suitable for intelligent lighting management in modern underground parking lots.

[0008] To achieve the above object, the technical solution adopted by the present invention is:

[0009] A GMI-based intelligent light control sensor, comprising an excitation signal module, a GMI module, a signal processing module, a microcontroller module, an LED light module and a power management module connected in a circuit;

[0010] The excitation signal module is used to generate a high-frequency excitation signal to drive the amorphous wire in the GMI module to produce a giant magneto-impedance effect;

[0011] The GMI module includes an amorphous wire and a detection coil wound around the amorphous wire, which is used to detect the impedance change of the amorphous wire caused by the change of the external magnetic field and convert it into an induced voltage signal;

[0012] The signal processing module is connected to the detection coil in the GMI module, and is used to amplify the induced voltage signal generated by the GMI module and perform low-pass filtering to obtain a processed analog signal;

[0013] The microcontroller module is used to convert the analog signal into a digital signal representing the strength of the external magnetic field, and adjust the brightness of the smart lamp in the LED lamp module according to a preset threshold;

[0014] The power management module is used to supply power to all other modules.

[0015] Compared with traditional sensors, GMI sensors have higher sensitivity, stronger anti-interference ability, lower power consumption, and are not affected by external factors such as light and temperature. The present invention provides a GMI-based intelligent light control sensor that can automatically adjust the brightness of the lights in the field according to the approach / distance of the sensing vehicle. It is an efficient, low-power and anti-interference intelligent light control solution suitable for intelligent lighting management in modern underground parking lots.

[0016] The amorphous wire is a cobalt-based amorphous wire or an iron-based amorphous wire.

[0017] The excitation signal module includes a high-frequency oscillator and a driving circuit;

[0018] The high-frequency oscillator is used to provide a stable high-frequency excitation signal as an excitation source of the GMI module, which is used to drive the amorphous wire of the GMI module;

[0019] The driving circuit is used to amplify the power of the high-frequency excitation signal generated by the high-frequency oscillator to meet the current demand of the GMI module and ensure that the high-frequency excitation signal can effectively drive the GMI module.

[0020] The GMI module detects the impedance change of the amorphous wire caused by the change of the external magnetic field and converts it into an induced voltage signal, specifically including:

[0021] When the amorphous wire is excited by a high-frequency excitation current and senses a change in the external magnetic field, that is, when a vehicle approaches or moves away, an impedance value change occurs; the detection coil converts the impedance value change of the amorphous wire into an induced voltage signal that is proportional to the change in the external magnetic field.

[0022] The signal processing module includes a signal amplification circuit and a low-pass filtering circuit; the signal amplification circuit is used to amplify the weak signal of the GMI module, and the low-pass filtering circuit is used to perform high-frequency denoising on the signal to obtain an induction signal containing information on changes in the external magnetic field strength and magnetic field direction.

[0023] The microcontroller module includes an analog-to-digital conversion module (ADC) module and a pulse width modulation module (PWM) module; the ADC module is used to convert a voltage signal into a digital value representing the external magnetic field strength; the PWM module adjusts the output according to the comparison between the threshold and the digital value of the external magnetic field strength converted by the ADC module to control the brightness of the smart lamp in the LED lamp module.

[0024] Furthermore, the PWM module controls the brightness of the smart lamp in the LED lamp module by adjusting the duty cycle of the PWM, thereby adjusting the duration of the high level in the output signal, thereby adjusting the brightness of the LED smart lamp.

[0025] The LED lamp module is provided with three brightness states: off, low brightness and high brightness.

[0026] The high-frequency excitation signal generated by the excitation signal is selected in advance, and the parameter when the maximum GMI effect is selected is the high-frequency excitation signal; the excitation signal includes a sinusoidal signal or a pulse signal.

[0027] Using a signal generator as an excitation source, the frequency, amplitude and other parameters of the excitation signal module are changed to test the optimal GMI ratio of the GMI module, thereby determining the optimal excitation signal parameters of the sensor and obtaining the optimal high-frequency excitation signal.

[0028] The excitation signal includes a sinusoidal signal or a pulse signal.

[0029] The present invention also provides the application of the GMI-based intelligent light control sensor in an underground parking lot, where the intelligent light control sensor is installed under the road surface of a lane or on the ground of a parking space to ensure that it can accurately sense changes in magnetic field signals of passing vehicles.

[0030] During installation, the direction of the sensor relative to the geomagnetic field is adjusted according to the layout of the parking lot, so that it is in an off or low-brightness state. When the target vehicle approaches, the light brightness is automatically adjusted from off to low-brightness state and then to high-brightness state, or from low-brightness state to high-brightness state, so as to save energy.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] The underground parking lot intelligent light control sensor based on GMI technology in the present invention can automatically adjust the light brightness according to the magnetic field changes when the target vehicle approaches / moves away, and has high sensitivity, low energy consumption and strong environmental adaptability. Compared with traditional sensors, GMI sensors have stronger anti-interference ability to environmental interference, can effectively improve the intelligence level of parking lot lighting systems, reduce energy waste, and have significant energy-saving effects and broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the structure of the intelligent lighting control sensor circuit module for underground parking lots based on GMI.

[0034] Figure 2 Schematic diagram of the structure of the excitation signal module and the GMI module in the embodiment.

[0035] Figure 3 Schematic diagram of the signal processing module in the embodiment.

[0036] Figure 4 Schematic diagram of the structure of the microcontroller module in the embodiment.

[0037] Figure 51 is a PWM waveform diagram with duty cycles of 30% and 60% in the embodiment.

[0038] Figure 6 FIG. 4 is a diagram of a power management module in an embodiment. DETAILED DESCRIPTION

[0039] In order to make the purpose, technical scheme and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with embodiment. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention. Those skilled in the art can make modifications or equivalent substitutions based on the understanding of the technical scheme of the present invention without departing from the spirit and scope of the technical scheme of the present invention, and all should be included in the protection scope of the present invention.

[0040] Example 1

[0041] like Figure 1 As shown, a GMI-based intelligent light control sensor includes an excitation signal module 1, a GMI module 2, a signal processing module 3, a microcontroller module (MCU) 4, an LED light module 5 and a power management module 6 connected in a circuit;

[0042] like Figure 2 As shown, the excitation signal module 1 includes a high-frequency oscillator 11 and a driving circuit 12, which are used to generate a high-frequency excitation current to drive the amorphous wire in the GMI module 2 to produce a magneto-impedance effect; the high-frequency oscillator 11 is used to provide a stable high-frequency excitation signal as an excitation source for the GMI module 2, which is used to drive the amorphous wire of the GMI module 2; the driving circuit 12 is used to amplify the power of the high-frequency excitation signal generated by the high-frequency oscillator 11 to ensure that the high-frequency excitation signal effectively drives the GMI module 2.

[0043] The GMI module 2 includes an amorphous wire 21 and a detection coil 22 wound around the amorphous wire. The high-frequency oscillator 11 described in this embodiment generates a sinusoidal signal with a frequency of 15MHz, which is driven by a voltage follower to improve its load capacity. One end of the current-limiting resistor R1 is electrically connected to the drive circuit 12, and the other end is electrically connected to the amorphous wire 21. The amorphous wire 21 is a commercially available cobalt-based amorphous wire. Under high-frequency excitation, its impedance changes with the intensity and direction of the external magnetic field. When the target vehicle enters the detection range of the sensor, the magnetic field of the vehicle affects the magnetization direction of the amorphous wire 21, resulting in a change in the impedance value at both ends of the amorphous wire 21. This change is converted into an induced voltage signal proportional to the change in the external magnetic field through the detection coil 22, providing a basis for subsequent signal processing.

[0044] The signal processing module 3 is as follows Figure 3As shown, it is connected to the detection coil in the GMI module, mainly to ensure the signal quality of the system output, and is used to amplify the weak signal output by the GMI module 2 and remove the high-frequency noise therein. The module includes a signal amplification circuit 31 and a low-pass filter circuit 32. In this embodiment, the induction signal of the detection coil 22 is electrically connected to the signal amplification circuit 31, and the low-pass filter circuit 32 is electrically connected to the signal amplification circuit 31. The low-pass filter circuit 32 adopts an RC filter. The signal after low-pass filtering can effectively remove high-frequency noise and retain the induction signal containing effective information such as the strength and direction change of the external magnetic field.

[0045] The MCU module 4 is as follows Figure 4 As shown, it includes an ADC module 41 and a PWM module 42. The MCU receives the analog signal from the GMI sensor after signal processing, and converts it into a digital value through its built-in ADC module, indicating the strength of the external magnetic field. According to different magnetic field strengths, the MCU adjusts the output duty cycle through the PWM module to control the brightness of the LED light.

[0046] Specifically: When the target vehicle approaches, the magnetic field increases, and the MCU increases the duty cycle of the PWM output to control the brightness of the LED light from off, low brightness to high brightness. When the target vehicle leaves, the magnetic field weakens, and the MCU reduces the duty cycle of the PWM output to dim the LED light and eventually turn it off. According to the range of the ADC value, the duty cycle is set to the following three states:

[0047] Light off state: When the sensor output signal is lower than the preset threshold (such as ADC value <100), the PWM duty cycle is 0% and the light is off.

[0048] Low light state: When 100≤ADC value<600, the PWM duty cycle is 30%, such as Figure 5 As shown in (a), the light is in low brightness state.

[0049] Highlight state: When the ADC value is ≥ 600, the PWM duty cycle is 60%, such as Figure 5 (b) The light is shown in high brightness.

[0050] The power management module 6 is used to provide a stable power supply for the entire sensor system. The module converts the input 5V DC voltage into a 3.3V stable voltage. Figure 6 As shown in (a), 5V and 3.3V voltages are used by the MCU, signal processing module and other circuits to ensure that the system can operate stably under working conditions. Decoupling capacitors are required around the MCU power pins, such as Figure 6 As shown in (b), it is mainly used to filter out noise and keep the voltage of the MCU power pin stable.

[0051] In order to ensure that the sensor can accurately sense the magnetic field signal of the target vehicle, the sensor of the present invention should be installed under the road surface of the lane or on the ground of the parking space. The installation position should ensure that the track of the vehicle passing can be covered while avoiding interference from other metal objects (such as iron components). During installation, the direction of the sensor can be adjusted as needed so that it is off or in a low-brightness state when there is no target vehicle approaching. When a target vehicle approaches, the light brightness will increase to a high-brightness state, thereby effectively saving energy.

[0052] The GMI-based underground parking lot intelligent light control sensor system of this embodiment can achieve the goal of automatically adjusting the light brightness according to the change of the vehicle magnetic field through precise magnetic field sensing technology. The system has the characteristics of high sensitivity, low power consumption, anti-interference, and fast response. In addition, the flexible installation and adjustment methods enable the system to adapt to the actual needs of various underground parking lots and have broad application prospects.

Claims

1. A GMI-based intelligent lighting control sensor, characterized in that: It includes an excitation signal module, a GMI module, a signal processing module, a microcontroller module, an LED light module and a power management module connected by a circuit; The excitation signal module is used to generate a high-frequency excitation signal to drive the amorphous wire in the GMI module to produce a giant magneto-impedance effect; The GMI module includes an amorphous wire and a detection coil wound around the amorphous wire, which is used to detect the impedance change of the amorphous wire caused by the change of the external magnetic field and convert it into an induced voltage signal; The signal processing module is connected to the detection coil in the GMI module, and is used to amplify the induced voltage signal generated by the GMI module and perform low-pass filtering to obtain a processed analog signal; The microcontroller module is used to convert the analog signal into a digital signal representing the strength of the external magnetic field, and adjust the brightness of the smart lamp in the LED lamp module according to a preset threshold; The power management module is used to supply power to all other modules.

2. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The amorphous wire is a cobalt-based amorphous wire or an iron-based amorphous wire.

3. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The excitation signal module includes a high-frequency oscillator and a driving circuit; The high-frequency oscillator is used to provide a stable high-frequency excitation signal as an excitation source of the GMI module, which is used to drive the amorphous wire of the GMI module; The driving circuit is used to amplify the power of the high-frequency excitation signal generated by the high-frequency oscillator to ensure that the high-frequency excitation signal effectively drives the GMI module.

4. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The GMI module detects the impedance change of the amorphous wire caused by the change of the external magnetic field and converts it into an induced voltage signal, specifically including: The amorphous wire, under the excitation of the high-frequency excitation current, generates impedance value changes when sensing changes in the external magnetic field; the detection coil converts the impedance value changes of the amorphous wire into an induced voltage signal proportional to the changes in the external magnetic field.

5. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The signal processing module includes a signal amplification circuit and a low-pass filtering circuit; the signal amplification circuit is used to amplify the weak signal of the GMI module, and the low-pass filtering circuit is used to perform high-frequency denoising on the signal to obtain an induction signal containing information on changes in the external magnetic field strength and magnetic field direction.

6. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The microcontroller module includes an ADC module and a PWM module; The ADC module is used to convert the induced voltage signal into a digital signal representing the external magnetic field strength; the PWM module adjusts the output according to the comparison between the threshold and the digital value of the external magnetic field strength converted by the ADC module to control the brightness of the smart light in the LED lamp module.

7. The GMI-based intelligent lighting control sensor according to claim 6, characterized in that: The PWM module controls the brightness of the smart light in the LED lamp module by adjusting the duty cycle of the PWM, thereby adjusting the duration of the high level in the output signal to adjust the brightness of the LED smart light.

8. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The LED lamp module is provided with three brightness states: off, low brightness and high brightness.

9. The GMI-based intelligent lighting control sensor according to claim 1, characterized in that: The high-frequency excitation signal generated by the excitation signal is selected in advance, and the parameter when the maximum GMI effect is selected is the high-frequency excitation signal; the excitation signal includes a sinusoidal signal or a pulse signal.

10. Application of the GMI-based intelligent lighting control sensor in an underground parking lot according to any one of claims 1 to 9, characterized in that: The intelligent light control sensor is installed under the road surface of the lane or on the ground of the parking space, so that the sensor can sense the change of the magnetic field signal of the passing vehicle.

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