First, the high and low frequency of the electrodeless lamp Second, the technical dilemma of high frequency electrodeless lamps 1. The luminous efficacy of high-frequency electrodeless lamps is too low, generally within 70LM/W. As far as I know, the efficacy of high-frequency electrodeless lamps has not exceeded 72LM/W. Even when it reaches 72 LM/W or more, this light effect is also peculiarly low compared to sodium lamps and metal halide lamps, and is far lower than some high-efficiency fluorescent lamps with filaments.
Any illuminating lamp without a filament electrode is an electrodeless lamp. In fact, the microwave lamp is also in the category of an electrodeless lamp. There is no filament electrode inside the microwave lamp, it is a 2450MHz microwave to stimulate the sulfur inside the bulb body. Sulfur is directly excited to emit very strong white visible light after microwave excitation. Sulfur does not pollute human living environment, so microwave lamps are not only mercury pollution, but also no UV pollution and phosphor pollution of phosphors. It is a true green light source. At the same time, the spectrum of the light of the microwave sulfur lamp is very close to the spectrum of sunlight, and it is the most similar daylight illumination. This kind of lighting with true sunlight is a cornucopia cash cow for planting farming. The removal of filaments from lighting is a major advancement in lighting technology and certainly the direction of human lighting. The lamp without the electrode does not have the loss of the filament. The life of the filament is naturally prolonged. At the same time, there is no ablation of the sputtered filament residue to contaminate the phosphor, which seriously affects the luminous ability of the phosphor to cause the light decay of the energy-saving lamp. This is the induction lamp ratio. One of the reasons for the decline in energy-saving lighting. Why is there a debate about the high and low frequencies of the electrodeless lamp? Where is the development of the electrodeless lamp? Is it the direction and not the detour? The high and low frequency of the electrodeless lamp is judged from their working frequency. The operating frequency of the high-frequency electrodeless lamp is 2650KHz, and the working frequency of the low-frequency electrodeless lamp is between 150K and 300KHz, and more 230KHz is selected. The reason for the high and low frequency difference is very simple: the 2650KHz high frequency electrodeless lamp has great technical difficulty, and there are more difficulties in design and production. The use of 150K ~ 350KHz low-frequency electrodeless lamps is relatively easy in technology, and there are ready-made 150K ~ 350KHz power supply circuit chips can be used. So what are the technical difficulties that are difficult to solve in high-frequency induction lamps?
2, high-frequency electrodeless lamp because the temperature inside the cavity is very high, its heat dissipation is not easy to solve, the power does not dare to do too much, generally does not exceed 165W. There is a claim to make 200W, but the luminous flux of it has not been increased by physical testing, and it has no practical significance. In this way, the power of the high-frequency electrodeless lamp is too small, and the luminous flux is not high, and it is not suitable for use in many occasions, so its application range is limited.
3. The EMC index of high-frequency electrodeless lamps is difficult to reach the standard. There are two transmission paths for electromagnetic interference: one is radiation and the other is conduction. The question is how can these two transmission channels completely block it and make the leakage of electromagnetic waves smaller to meet the increasingly strict EMC index? ?
4, the life of high-frequency electrodeless lamps, especially the long-term gap between the life of the high-frequency power supply and the propaganda is too large, it is impossible to reach 60,000 hours of service life. Can it be achieved in 20,000 hours? I see it hard.
5, the cost of high-frequency electrodeless lamps is still relatively high, and the external form is small. In particular, it is very demanding on the installation of the street lamp, and the heat dissipation capability of the casing is extremely high. Otherwise, the electrodeless lamp cannot work normally for a long time. In essence, the heat of the high-frequency electrodeless lamp is quite powerful.
Third, the eight misunderstandings of the low frequency induction lamp
Low-frequency electrodeless lamps In view of the technical difficulties of high-frequency electrodeless lamps, low-frequency technology is used to solve the problems of light efficiency and heat dissipation. This method of evacuation is easy to understand and is completely understandable. But the problem is that this method of disposal is not 100% perfect, and it may bring other unexpected flaws. It is a scientific attitude to face up and try to solve them.
1. The international standard issued by the International Committee on Radio Interference (CISPR) of the International Electrotechnical Commission (IEC) [CISPR15] (the fourth edition of 1992) clearly stipulates that the electromagnetic induction lamp has two operating frequencies: I, 13.65 MHz Japan's Matsushita's Everlight electrodeless fluorescent lamp is working in this band. The biggest advantage of this band is that it has a frequency of 27MHz near the amateur radio frequency band, and its EMC index is more relaxed and easy to pass. II, 2.2 ~ 3MHz band. It is between medium and short waves and is rarely used for radio broadcast and reception. The Philips QL Promise Fluorescent Lamp and the General Electric Genura Promise Fluorescent Lamp from the Netherlands have chosen this band, they all work at 2.65MHz (ie 2650KHz). 2400M~2500MHz is a non-communication segment, and the microwave oven works in this band. Today's microwave sources also use this frequency. The low frequency induction lamp operating frequency of 230KHz or nearby frequency is an illegal frequency band that is not recognized by international organizations. It has the same frequency interference that is extremely difficult to eliminate for aviation, communication, broadcasting, radio and other equipment. The final outcome is bound to be banned, so the low frequency The electrodeless lamp is destined to have no prospects for development.
2. The working frequency of the low frequency lamp is about one tenth of that of the high frequency lamp, the volume of the corresponding magnetic component is also increased by 10 times, the inductance of the coupler is increased from about 13 μH to about 150 μH, and some lamps have two more. . The volume of the magnetic components in the power supply is also greatly increased, and the volume of the whole lamp is not small but becomes larger, and the weight and cost are also greatly increased. Especially as the country increases the control of rare earth materials, the price of rare earths in the world has nearly turned over 10 times. What are the reasons for the low-frequency electrodeless lamps that consume more magnetic materials?
3. The coupler externally solves the heat dissipation problem of the electrodeless lamp slightly, but the coupler is completely exposed in the space, and half of the electromagnetic energy is wasted and become a source of interference. The operating frequency of the low-frequency lamp seems to be 10 times lower than that of the high-frequency induction lamp, but it is nearly 10 times higher than the operating frequency of the energy-saving lamp ballast. The unobstructed free radiation in space is definitely a technical one. Regression. The EMC index of low-frequency induction lamps is still a relatively big problem. Someone asked: Since the externalization of the low-frequency lamp coupler will bring more serious EMC problems, how can the high-frequency induction lamp that interferes with the aeronautical signal at the Shenzhen Airport explain? This incident can only show that the high-frequency electrodeless lamp is shoddy and there are still a lot of technical shortages that need to be greatly improved, but it is not the ugly cloth of the low-frequency electrodeless lamp technology, nor is it an excuse for rejecting technological progress.
4. Practice has proved that low-frequency lamps are more prone to stop vibration than high-frequency lamps, that is, suddenly turn off the lights. The more difficult it is to compare the two in a harsh environment, this is an indisputable fact. The reason for the analysis is nothing more than the magnetic component. Since the coupler of the low-frequency electrodeless lamp is placed on the lamp, it does not take any heat-dissipating measures. The heat of the lamp is high, and the heat above the coupler cannot be ruled out, eventually causing the decoupling of the coupler to extinguish the lamp. At the same time, the low-frequency lamp coupler and the higher-frequency lamp coupler are more difficult to match with the power supply, and the matching degree of the finished product is more rough and the efficiency is not high.
5. The shape of the low-frequency lamp is special. Especially the rectangular tube is difficult to manufacture at the corner, and the cost will increase. In addition, it is not easy to be miniaturized, so it is difficult to popularize into the family. At the same time, special lamps are required to be matched with them: 1 for special purpose; 2 for shielding. The cost will double after anything is dedicated. Moreover, the electromagnetic wave interference that relies on the luminaire to shield the low-frequency lamp is limited, and the effect cannot be determined. It is meaningless to talk about the technique of hypothesis. Now the price of low-frequency induction lamps is relatively high, and there is no possibility of decline in the near future. Therefore, there are more problems in the market competitiveness of low-frequency induction lamps.
6. A number of foreign large-scale lighting companies represented by Osram have recently applied for all patents related to low-frequency electrodeless lamps in the world, and they have only waited for us to drill into its patent traps. Drink blood. Because the high-frequency lamp has passed the 50-year patent protection period, there is no patent dispute.
7. Watching the development history of light source, its working frequency has experienced a process from low to high: incandescent lamps are first used for direct current, then 50Hz alternating current; fluorescent lamps are also rapidly transitioning from low frequency inductive ballasts to high frequencies. Electronic ballast. Now the 2.45GHz microwave light source has already been lighted in the United States and has received worldwide attention. It is also booming in all parts of the country and is developing with great momentum. Why do people have to constantly pursue higher working frequencies? This is because only the higher operating frequency of the power supply is likely to achieve higher power density and higher efficiency, which means that we can get a smaller and cooler heat source with the lamp. . Is there a good result when the low-frequency electrodeless lamp is contrary to the development trend of the backlight source?
8, in terms of light attenuation, the results of low-frequency lamps are more pessimistic, the results of high-frequency lamps are better. Some data show that less than 2000 hours, the light decay of low-frequency electrodeless lamps has reached more than 30%, and has reached the scope of scrapping. Why it came out like this? Is it a very special individual phenomenon that represents the general result of low frequency induction lamps? I hope my friends can provide more real data for analysis. Some people think that because the temperature at the low-frequency electrodeless lamp coupler is too high, it burns the phosphor, which affects its life. Whether this is the cause of the need to discuss business, but also more test results and theoretical analysis to confirm.
Fourth, the entanglement of high and low frequency induction lamps
At this stage, the low-frequency electrodeless lamp is sold as a transitional product of the electrodeless lamp. It is good because it has higher light efficiency than the high-frequency lamp and has a larger choice of shape, but it wants to become mainstream. There are many difficulties in replacing the metal halide lamp and sodium lamp with the light source. It is impossible to do it at most. Some manufacturers of low-frequency electrodeless lamps claim that the way out of the electrodeless lamps is to develop to a lower frequency. They have already produced 140KHz products and are still preparing to develop products below 100KHz. I think it is a bit too much. The high frequency electrodeless lamp encounters a technical problem, which can be gradually solved with the development of technology and technological progress. The low-frequency induction lamp encounters structural problems. These problems can not only be solved with the development of technology, but the contradiction is more prominent and will be deeper into trouble. The low-frequency electrodeless lamp does not represent the development direction of the electric light source. There is no doubt that the progress of the electric light source to a higher working frequency is the correct development trend and trend direction.
Some treacherous businessmen carried out weird packaging on the induction lamp, and rejected their high and low frequency induction lamps as an induction lamp, but instead called a "magnetic lamp" or a "magnetic lamp." In fact, it is not wrong to call it "magnetic lamp" or "magnetic lamp", but they claim that their magnetic lamp performance far exceeds that of the electrodeless lamp. Because their lamps contain magnetic energy in addition to electric energy, it is the world's electric light source technology. The major inventions and special breakthroughs, the author has nothing to say, only swearing: really too bluff! Maxwell's equations, which are known to middle school students, are the four basic equations that the British physicist Maxwell established in the 19th century to describe electric and magnetic fields. Its differential form is often referred to as Maxwell's equation. In Maxwell's equations, the electric and magnetic fields are an inseparable whole. The system of equations completely summarizes the basic laws of electromagnetic fields and reveals the properties of electromagnetic waves. The core idea of ​​the vortex electric field and displacement current hypothesis proposed by Maxwell is that the changing magnetic field can excite the vortex electric field, and the changing electric field can excite the vortex magnetic field; the electric field and the magnetic field are not isolated from each other, they are interconnected and mutually excited to form a unity. Electromagnetic field. Maxwell further integrated all the laws of electric and magnetic fields to establish a complete electromagnetic field theory system. The core of this electromagnetic field theory system is Maxwell's equations. Maxwell has long proved that magnetic and electric fields cannot be separated from each other, and it is even less likely to be added separately.