Application of Environmental Adaptive Control Technology in LED Outdoor Lighting

1 Introduction

In the LED industry there is Moore's Law-Haitz's law similar to the microprocessor industry. That is, the price of an LED will be 1/10 of its original value every 10 years, and its performance will be increased by 20 times. With the rapid advancement of lighting technology, the LED industry has developed rapidly in recent years. At the same time, due to the characteristics of green, environmental protection, energy saving and high efficiency, the LED has also received strong support from the government.

The development trend of LED lighting is high technology, high added value, intelligence and modularization. It can be seen that intelligent LEDs will become a major trend in the future of outdoor lighting products.

Intelligent lighting control has two connotations: First, it can achieve the purpose of energy conservation and environmental protection, and second, it can provide appropriate light sources according to people's needs. Only by combining lighting and intelligent technologies can the lighting further meet the lighting needs of different individuals and different levels of groups and achieve on-demand lighting.

2 Control Technology Development

The core element of control technology is the microprocessor. In the past 20 years, the degree of integration of microprocessors has been significantly improved, and performance has been significantly improved while reducing power consumption. Microprocessors include microcontrollers, DSPs, FPGAs, and ARMs.

SCM: After the 90s, the microcontroller technology has been greatly improved. Monolithic microcontrollers have gradually evolved from monolithic microcontrollers to monolithic microcontrollers. To meet the application system's maximum solution on the chip, MCUs have become SOC-based and extended to the monolithic application system stage. Different MCUs can meet different intelligent control requirements.

DSP: In the 90's, DSP has been widely used in data communications, mass storage, voice processing, video processing, etc. With the development of technology, DSP began to merge with FPGA, high-end CPU, etc., DSP branch prediction and dynamic buffer technology into high-end CPU , greatly improving the performance, and FPGA integration into the DSP core, greatly improving the signal processing speed to enable it to support multiple data streams. DSP's high operating speed and powerful data processing capabilities enable a large amount of digital information to be processed in a short time. This is a microcontroller that cannot be completed.

FPGA: FPGA is a digital system core chip following the processor and DSP. In these 24 years, FPGA technology has undergone revolutionary changes both in terms of chip separation and complexity, making it more flexible and parallel. FPGA constantly integrates various hard and soft IP cores, which is more conducive to SOC design. The FPGA EDA tool can be used to design up to hundreds of thousands of gates and two levels of logic design. Complex programs cannot be completed manually.

ARM: ARM is the core component of the embedded system under RISC architecture. It is widely used in many fields such as control and wireless communication. The development of ARM can improve the intelligence of the target system, control force and human-computer interaction capability. The ARM Partner Alliance has more than 500 companies and can provide a wealth of design and solutions.

In addition to the core microcontrollers, LED lighting control technology incorporates sensor technology, intelligent control technology, network technology, and multimedia technology. With the development of the Internet of Things, Internet of Things technology is gradually applied to outdoor lighting.

Applying intelligent control technology to outdoor lighting has the following advantages:

1) extend the life of the light source

2) Automatic dimming, energy saving during operation

3) Full use of light sources

4) Consistency of illumination

5) With artistry and flexibility to meet personalized, hierarchical lighting

6) Realize light-environment-human interaction and develop into smart cities

Smart lighting is an important means for lighting to further green and sustainable development. In the future, smart lighting will be the mainstream trend of LED lighting.

3 application of lighting products

The implementation of LED lighting is aimed at energy saving, and the use of LED as an outdoor lighting base to achieve further energy saving through control technology is a very significant thing.

Most of the traditional infrared sensing technology is used for indoor lighting. He judges by detecting the temperature of the human body. In summer, there are many objects whose temperature is close to the human body. Moreover, the detection transmission distance is very short and the furthest distance is within 3 meters, so it is not suitable for outdoor lighting applications. Through research experiments, the use of microwaves in the natural light spectrum can achieve this function. Microwave refers to an electromagnetic wave with a frequency of 300MHz-300GHz, which is an abbreviation of a limited frequency band in radio waves, ie, an electromagnetic wave with a wavelength between 1 meter (excluding 1 meter) and 1 millimeter, which is a decimeter wave, a centimeter wave, and a millimeter wave. Sub-millimeter wave

China Lighting Network Technical Papers • LED Lighting It uses the Doppler effect to sense moving objects. When a person walks into a light fixture, it gradually brightens up to meet the brightness requirements. When no moving objects are sensed, the brightness will be automatically reduced and the lamp power will be reduced to achieve energy-saving effect.

The 10.525GHZ microwave is used for the luminaire. The transmitting antenna emits microwaves outwardly. When a moving object is encountered, the signal is reflected. The reflected wave is received by the receiving antenna. After mixing, the low frequency signal is sent to the control section after detection. Low-frequency signals include three types of signals: Doppler shift signals, DC signals, and noise signals.

When the object moves radially relative to the microwave detection sensor at a speed of 1 m/s within the effective detection range of the microwave detection sensor, the IF output of the microwave detection sensor is 72 Hz/s, and the pulsating output frequency of the IF is relative to the radial movement of the object. The speed becomes approximately linear. The IF output amplitude is related to the size and distance of the object. When a tester with a body weight of 70kg and a height of 170cm moves radially with respect to the microwave detection sensor at a speed of 1m/s from HB1001m, the IF output is 5mV, 72Hz/ s pulse signal, the output amplitude of the IF is approximately inversely proportional to the square of the distance

After the low-frequency signal is amplified and filtered by the analog circuit and sampled, the MCU operates on the digital signal and calculates the amplitude and frequency of the waveform fluctuation. The amplitude represents the distance of the moving object, and the frequency represents the speed of the moving speed (the Doppler signal frequency of most people goes below 100 Hz). After the calculation is completed, corresponding intelligent control is performed.

The product is also characterized by the design of software programs, signal shielding to filter small movements, such as small animals, leaf movements, and light wind blowing lampposts and other erroneous information.

In addition to the above technologies, we also apply Internet technology, multimedia technology, etc. to outdoor lighting to meet the increasingly complex application environment and make lighting closer to people's needs. At the same time, we also studied the city's intelligent lighting control technology. Designers used intelligent control technology to achieve more people's creativity in lighting.

4 Conclusion

The development of intelligent lighting control technology will enable outdoor lighting to achieve energy-saving goals through light-environment-human interaction. Lighting fixtures will also not be unconnected individuals but networked, multimedia lighting.

We are committed to outdoor lighting, we are determined to be smart lighting pioneers; we work hard to bring you more and better smart LED products close to our lives.