LED drive power of the development of the five concepts
At present, the fault of LED lamps is mainly in the power supply, so solving the main contradiction is to solve the power supply problem. Due to the lack of mandatory unified standards for LED power supply, the power supply on the market is self-governed, single-way, multi-way, and different sizes, resulting in many problems. With the emergence of super-high power LED power supply on the market, more than four driving power sources are everywhere, so frequent failures, but also due to the overall design cost of LED street lights, styling difficulties, many factors overlap, often resulting in difficulties in maintaining the LED power supply, so it is the owners'complaints, media incitement and ignition that cause everyone to L. The misunderstanding of ED street lamp has affected the reputation and development of industry.
Five concepts of the development of LED driver power supply:
1. Give up high-power, super-high-power and develop medium and small power supply with high stability, preferably between 30W and 40W, and the maximum should not exceed 50W.
Because the greater the power, the greater the calorific value, the more compact the parts inside, which is not conducive to heat dissipation, and temperature is the main culprit of power failure. Moreover, the development of low power supply is relatively mature, and it has advantages in stability and cost. In fact, many power companies know that the greater the power, the harder it is to do, and they are unwilling to do large power. However, under the pressure of application manufacturers, passive development of high-power power supply, many schemes have not been time-tested and proved by practice. They are all projects launched in a hurry and are experimental products, so the failure is endless. In contrast, because of the early development of medium and small power supply, the technical scheme is more mature.
Moreover, because of its large size, the installation of high-power and super-high-power power supply is not flexible. Because of its small size, the installation of small and medium-sized power supply is more flexible.
2. Abandon more than four outputs, develop single or two outputs, abandon large and super-large currents, and develop small currents.
The more output routes, the more difficult it is to do, and the higher the failure rate. So far, no power supplier has been able to stand up and pat his chest and say, "In today's harsh cost requirements, under the premise of more than four drive guarantees are no problem." The more the number of output circuits, the greater the total output current, and the current is the main reason for heating. Voltage can not heat, but current must heat, and simple calculation can be considered that the heating power and the square of current are proportional, that is to say, if the current increases to twice the original, the heating power will increase to the original. Four times the current, three times the current, and nine times the heating power. So I suggest that the current should be controlled below 1A.
3. Intelligent control should be one of the greatest advantages of LED lamps, and intelligent control is also the intelligent control of power supply.
Intelligent control is particularly important in the application of street lamp and tunnel lamp lighting. As far as street lamp is concerned, intelligent control can realize stepless control of lamp power in different time periods and according to road traffic density, which not only meets the application requirements, but also achieves energy-saving effect. The application of tunnel lighting is more important. It can automatically adjust the brightness of tunnel entrance and exit according to the brightness outside the tunnel, and provide a safe driving environment for drivers.
4. Heat dissipation and protection are the main external factors of power failure.
Not only the power supply itself will be heated, but also the lamps will be heated. How to distribute these two heat sources reasonably is a problem that must be considered by the lamp design engineers. We must prevent the excessive concentration of heat, form heat island effect and affect the life of the power supply. In addition, the problem of protection is also very important. Water penetration may cause short circuit of power supply. Sand and dust on the shell will affect the heat dissipation of power supply. Exposure will easily cause high temperature and aging of wires and other components. Protection is actually to solve these problems.
5. Feasibility of maintenance.
Despite our efforts in the first four steps, it is still impossible to completely avoid the power failure problem, which is the reason why we put forward the feasibility of maintenance. Lighting design engineers should consider the maintenance of power supply. Only when the replacement of power supply is as simple as the replacement of light source of conventional lighting, can the maintenance task be transferred to the street lamp unit.
In this regard. We should work hard on the maintenance of lamps and lanterns. The simpler the designer is, the better. In the actual use process, the failure rate of rotary connector plug is higher, most of which are caused by water leakage. It has been recognized that the reasonable design method of modularization should be considered in the integration of modular power supply, because the overall power of modularization is small. If the power supply can be plugged and plugged in to solve the maintenance problem, it is the power supply that keeps the street lamp unit in stock. (It is not doubtful that part of the power supply today is relative to the life of the LED light source.)