Microwave technology matured during World War II for the development of radar. When the Great War will end, the United States adjusted the radar engineers found themselves in the pocket of the chocolate often melted! Immediately understand, this is the role of electromagnetic waves on the material caused by, is and high-power cable in the insulation medium loss of heat is the same thing. Curiosity drove them to use microwave devices for popcorn success. This is the prototype of microwave power application equipment. As early as the thirties in the debugging of high-power radio transmitters, often found flies or insects dried up dead in the hollow solenoid, these accidental discoveries, understand the revelation to the people of microwaves and radio waves can cause heating, drying phenomena. In fact, microwaves and radio waves are electromagnetic waves, only the frequency of microwaves in more than 300 MHz, while the frequency of radio waves in 300 MHz below. Of course, the development of radio technology in the early days of the work of technology focus on the use of various frequencies of electromagnetic waves to carry information or access to information in order to construct a modern colorful life. It was not possible to use expensive radio and radar equipment for heating and drying at the initial stage. The use of radio wave heating as an industrial application predates microwave heating, called radio frequency heating. With the development of microwave technology, the resulting microwave power continues to increase, the cost is reduced, it will be possible to transform the energy of the microwave electromagnetic field into the energy of the molecules of matter, as a means of scientific research, production and medical treatment. This penetration into the interior of the material, instantly transformed into molecular thermal energy, changing the traditional concept of heating from the surface to the inside, creating a new technology of rapid warming. 1. Principle and microwave power application equipment microwave electromagnetic waves have two transmission states. The first, is directed by the antenna to space propagation, and the same as light, is a straight line propagation. The second, is set up by man-made guide line transmission state, that is, constraints on electromagnetic waves in the hollow pipe transmission, this hollow pipe is called the waveguide, generally rectangular or round, made of copper or aluminum and other good conductors. Waveguide using the cross-section size and the frequency of the microwave used. Microwave electromagnetic waves propagated in the hollow waveguide, the energy is enclosed and transmitted. It can be transmitted over long distances with minimal energy loss. If the waveguide is filled with non-metallic substances, resulting in the loss of transmission power, the transmission distance is limited. Is due to the electromagnetic field and material interaction, has been part of the electromagnetic wave energy into the energy of the material molecules, the conversion ratio is and the frequency of the electromagnetic wave and the loss factor of the material related. In principle, it is possible to convert all the energy of the electromagnetic wave introduced into the closed transmission in the waveguide into the energy of the material molecules. An increase in temperature is the main sign of an increase in the energy of the molecules of matter. Electromagnetic waves are propagated at the speed of light, the speed of electromagnetic wave penetration into the material is also close to the speed of propagation and the speed of light; and the electromagnetic wave energy into the energy of matter molecules of the approximate time is instantaneous, in the microwave frequency band conversion time is faster than one ten millionth of a second. This is the microwave can constitute the principle of internal and external rapid heating at the same time. Conventional heating of solid materials, must be in a heated environment, and then from the surface to the inside, and gradually conduct into the interior of the solid, to obtain the conditions of thermal equilibrium, which requires a longer period of time. Heating environment, generally can not be very strict adiabatic closure, in a long time of heating, it may be on the environment exudes a lot of heat. And microwave power is all the cards closed state, with the speed of light penetrate into the object inside, instantly transformed into heat, it saves a long time in the heating process of heat dissipation, which is the energy-saving principle of microwave heating. Microwave heating and radio frequency heating compared to the characteristics of: a. Field energy into thermal energy is high; b. Easy to electromagnetic wave shielding up, do not escape the actual microwave power equipment, generally consists of (1) the microwave power source (2) the application of (3) waveguide elements and application of energy-feeding structure (4) the sensing and control of the four-part composition. Generate microwave power microwave power source, generally used magnetron for vibration, in the tube, the hot cathode emission of electrons, under the action of a strong constant magnetic field, the electrons for circular motion; magnetron inside the resonance cavity to make the electrons decelerate, so that the kinetic energy of the electrons, transformed into the energy of the electromagnetic wave, in the resonance cavity to accumulate, sent to the waveguide, and then into the application of the application of the use of the device. Magnetron needs DC high voltage power supply, filament heating power supply and constant magnetic field coil power supply and need the corresponding protection and control circuits, composed of microwave power source of the whole machine. DC high voltage or constant magnetic field excitation current, can control the microwave power output. Microwave applicator is an enlarged waveguide, using it as a place for electromagnetic wave and material interaction. Design considerations are adapted to the morphology of the processed material and processing requirements, can be divided into traveling wave type and harmonious vibration type. Waveguide element is the link between the microwave power source and the applicator, in order to solve the problem of both the magnetron to obtain the best working conditions of the load, but also to enable the applicator to obtain an effective feed-in effect, from the point of view of the microwave technology, it is through a variety of waveguide elements and feed the structure of the energy to be accomplished at the same time waveguide elements to provide the amount of incident power and the amount of overflow reflective power data. Sensors are configured to perceive the degree of field and material interaction, whether or not it meets the processing needs, such as temperature sensing and humidity sensing. Equipment can be based on real-time sensing data and microwave power source real-time operating status, the power source output and transmission speed to implement effective control. Microwave power application equipment is divided into four parts, is very necessary. In general, the application of equipment are single piece production or small batch production, is necessary in accordance with the specific requirements for the use of the design, is a similar "tailor-made" process. Microwave power application equipment is divided into four parts, including microwave power source and waveguide components are microwave engineering design, sensing and control engineering design. These three parts have a strong generality and are not subject to change depending on the application object. Over the years, we have strengthened the standardization and serialization of these three parts to improve the reliability and stability of these components, providing a strong basis for the reliability of the machine and shorten the cycle of development of the machine. Microwave applicator design has strong pertinence, due to different application object processing requirements, different states, shapes and sizes, is a multidisciplinary convergence of engineering design, we use the microwave applicator series design method, the different departments using specific common parts assembly, will be the new design of the parts down to very few, so that further shorten the development cycle of the equipment, and ensure the reliable quality of the equipment. 2. China's microwave power application of the current situation in China in the early seventies, the attention of foreign microwave power application technology development. As early as the end of 1972, the Ministry of Electronics Industry in Nanjing 772 plant (i.e., Sanle Electric Corporation) held a microwave tube technology seminar, focusing on the discussion of microwave tubes in the new field of application in the possible development of new fields, that is, microwave heating and drying of industrial applications, microwave therapy, microwave diagnostics and microwave plasma and other fields. And carry out research work in new areas of the precursor, must develop high-power continuous wave magnetron. In that year, 772 factory started to develop 915MHz and 450MHz continuous wave magnetron, and in the development of two frequency bands of continuous wave magnetron based on the success of the development of China's first 2450MHz microwave therapy instrument, and 915MHz microwave heating equipment. 1974 spring the first microwave heating equipment on display in Beijing, the demonstration of the phenomenon of microwave rapid heating, attracted the general concern of the industrial community. In November 1974, the Ministry of Electronics Industry held a symposium on microwave energy application technology in Nanjing 772 factory, which introduced the application of microwave power in industrial production, agricultural production and medical care in foreign countries, and discussed the prospect of development in China. After more than two decades of efforts, China has been the application of microwave power this research field to establish a preliminary foundation, 772 plant developed microwave power equipment has been in the food, wood and bamboo products processing, pharmaceuticals, paper products, brewing, rubber, chemical and other industrial production has been firmly rooted to improve the conditions of production, improve the quality of the product, the development of a variety of microwave plasma equipment, microwave high-temperature equipment and microwave vacuum Drying equipment has become an important means of scientific research in a variety of disciplines. In terms of the national situation, the promotion of microwave power application technology in China, more than two decades is a very arduous journey, made initial achievements, laid the foundation for the continued development of the basis of the main symbols of this foundation are: (1) microwave heating and drying, microwave food processing and microwave sterilization, insecticidal has been widely used in a variety of industries (2) household microwave ovens have formed a large-scale production capacity; (3) the clinical application of microwave medical instrument has made a generalized, and the microwave power application has become a very important means of scientific research. The clinical application of microwave medical instrument has achieved general success; (4) a number of areas of cutting-edge issues, the use of microwave power as a powerful tool, has made a lot of encouraging progress in expanding the new field of research positions, has kept pace with the world 3. Microwave power applications are moving towards high-tech areas from the world's research trends, the application of microwave power in the development of new areas of the period that the focus of the research has been from the traditional Heating and drying, food processing to a number of high-tech fields, as a new tool for research. The main areas are: microwave catalyzed chemical reactions, microwave processing of new materials, microwave gas discharge of a variety of applications such as research. Microwave chemistry experimental research, almost all over the chemical, chemical industry, a large number of selected reports show that the microwave electromagnetic field can accelerate the chemical reaction, can be shortened to the reaction time to the original time required for one-tenth to one-thousandth of the time, to the chemical industry to introduce an attractive prospect. Microwave high-temperature technology can sinter fine ceramics, can be welded ceramics, and can be processed and treated materials, such as polymer materials, heat-setting, non-metallic materials, heat treatment, microwave methods are superior to conventional methods. Microwave gas discharge, i.e., the formation of low-temperature plasma with microwave electromagnetic field, is a major aspect of microwave power application research. Microwave plasma chemical vapor deposition film (MPCVD) and plasma etching, is the main means of microelectronic processing processes, the preparation of diamond films and the preparation of optical fibers are also used in the MPCVD method, the preparation of ultrafine powder, microwave plasma method, has a variety of advantages. Microwave plasma, a variety of particle activity is stronger than the radio frequency plasma, for chemical reactions and materials processing has more favorable conditions. In addition, by the microwave electrode-free discharge constitutes a strong illumination light source (such as sulfur lamps), microwave odor generator, etc., it is possible to gradually move towards industrialization. According to the preliminary anthology of research, China is carrying out microwave power new areas of research work hot spots, can be listed as follows: (1) microwave beneficiation (microwave-assisted pyrolysis) research, non-ferrous metals, sulfide into oxides, nickel carbonate into nickel oxide, gold ore desulfurization and radioactive isotopes of nitrates into oxides and so on has been achieved in the laboratory results. (2) microwave-assisted organic and inorganic chemical reactions, improve the chemical reaction rate has done a lot of laboratory work. (3) microwave-assisted extraction technology research. Microwave electric field can accelerate the dissolution rate, improve solubility, has been in a variety of laboratories have achieved remarkable results. Microwave-assisted extraction methods, scientific and standardized production, will be the inevitable trend. (4) natural gas instead of oil to produce ethylene and other chemical raw materials, the use of microwave-assisted catalytic chemical reactions and microwave plasma technology, in the laboratory has achieved better yields. (5) The microwave regeneration method of activated carbon and diesel fuel filters has obtained good experimental results. (6) China as early as the early eighties began to develop a variety of microwave plasma equipment, such as MPCVD equipment, plasma etching equipment, laser microwave pump source development work. And began to develop microwave radio electrode discharge sulfur lamp strong light source, microwave gas discharge constitutes an ozone generator (in the ozone environment, to extend the shelf life of food, is an effective method). (7) microwave high-temperature technology for sintering ceramics and welding ceramics, China has achieved many experimental results. The trend abroad is conventional heating technology and combined with microwave high-temperature methods to improve the production of ceramic industry, there have been small-scale production equipment. China also has the foundation and experience in this regard, should start the work at an early date. (8) from the early eighties has been engaged in microwave desulfurization of coal and oil research work, the purpose of the combustion process in the hope that the early formation of clean emissions. The solid, liquid and gas waste treatment, also combined with microwave methods, carried out preliminary experimental research. From the content of these topics can be seen, the research work on new areas, the gap between China and foreign countries is not too big. Should be practical to solve many practical problems, in order to strengthen the transformation to industrialization, in order to see the effectiveness of China's economic construction and ecological environment improvement. 4. Strengthen the microwave application of basic research is the basic conditions for further development, as mentioned above, China's microwave power applications to new areas of pioneering experimental research work involves a wide range of accumulated experience, has achieved many pioneering research results, which is encouraging. However, the transformation of these laboratory results into productivity, so that the process of industrialization to catch up with the world's pace of progress is not yet optimistic. From the microwave engineering point of view, China's experimental research for new fields of equipment, is still relatively primitive state, and processing capacity is generally small, expanding to industrial scale, there are still many specific difficulties need to be resolved, towards industrialization there is still a period of hard work. Experimental research in new areas from abroad shows that: the need for microwave power application equipment with higher requirements. Stuck in the original level of equipment, difficult to adapt to the needs of the new field of research. First of all, the microwave power source on the higher requirements, the requirements of the work of high reliability, the output of microwave power with high stability and re-modulation accuracy, low ripple factor, and has a modulation function to adapt to change the conditions, to achieve better experimental results, and has a reliable repeatability. Second, the equipment far real-time sensing, monitoring and high-speed is needed. Sensing settings, is the weak link of domestic equipment, need to improve these functions. In order to ensure the accuracy of monitoring, and the reliability of the adjustment, the need to start improving the performance of high-power waveguide elements, and the development of a variety of adaptable feed structure of the applicator. It can be seen that, in order to meet the needs of the new field of applied research, microwave power source, waveguide elements and sensing and control of the three parts of the generality of the basic components, there are still a lot of improvement work to be done to make these basic components of the technical indicators of foreign advanced level. Has been successfully utilized microwave power production equipment, but also need to improve and enhance. Improvement of the quality of these general-purpose basic components will provide a solid foundation for the improvement of application equipment. It is possible to make the microwave power application equipment more standardized, so that the work is more stable and reliable, more uniform heating, and with reliable sensing functions, can make the working state of the equipment to get real-time monitoring, so that the state of electromagnetic field and material interactions with the perceptible, with the configuration of closed-loop self-control of the basic conditions of the equipment is becoming more and more perfect, so that we can narrow the gap between the advanced foreign similar products, so that the current domestic to imported equipment Rubber microwave vulcanization equipment and printing and drying equipment, all using domestic equipment. Once the quality of our application equipment jumped to a higher level, it is possible to apply microwave power to the heating of the field continues to broaden. Such as chemical materials, fiberglass drying, drying and shaping of ceramic blanks, textiles, printing and dyeing, printing industry applications, the application of large-scale thawing of frozen meat food, microwave power equipment can be used to improve production conditions and shorten production time. Existing microwave power application equipment to improve and enhance, and reliable use, will undoubtedly be a new field of application equipment provides useful experience and basic components. 5. Multidisciplinary convergence of research to make the early shift to industrialization of microwave power applications is a multidisciplinary cross-cutting issues, the new field of research, the full penetration of multidisciplinary is equally important. More than two decades of experience has shown that many applied disciplines of research work if not clear microwave principles of the basic framework, the main principles and the current situation, the establishment of the research topic will often be repeated many times for a long time in the laboratory, wandering, research progress is not fast, and is not clear about the application of discipline-specific issues of the basic requirements to deal with the main aspects of the microwave applications made by the engineering design will result in the use of improper, resulting in a large amount of waste. Resulting in a large amount of waste. Although these are the past history, but these should learn from the experience, we must pay high attention to the development of new areas of application, the more important significance. Microwave applications of research issues, there must be a multidisciplinary can be fully dialog from, penetration, and then find a multidisciplinary law of the meeting point of the process. Can not be ignored from the theoretical perspective of multi-disciplinary in-depth dialogue of the necessity of multi-disciplinary theory, because the laws of multi-disciplinary theory, can be predicted many directional principles, can be more reliable to give the application of the specific requirements of the design, and the actual operation of the experimental procedures, to avoid more detours, saving time. Multidisciplinary meeting should include both research work strategy, program and design, as well as failure and success of the experience of the discussion and summary, in order to cover the complete law of the research work, but to find the way forward. It is expected that the results of scientific research into productive forces, more attention should be paid to consider from the multidisciplinary convergence, the results of a scientific research project should also pay full attention to similar industries or existing industries of similar scale production of successful experience, to make the transformation of the industrialization of the program. Microwave technology does not replace all the laws of the original production process, microwave technology can find the weak links in the original production process, in this link to supplement, strengthen or replace, and make the original process to get a great span of improvement. Such as the development of microwave rubber vulcanization equipment is a clear example. Vulcanization temperature and vulcanization time for a certain product have a determined optimal interval, the conventional method is the heating time and vulcanization time of the contradiction, the large volume of products, from the surface and inside the conventional heating, in order to make the internal to reach a predetermined temperature of vulcanization, it takes a very long time, the surface layer of the rubber has exceeded the time of vulcanization, to reach the state of over-vulcanization, while the internal is still in the vulcanization process is insufficient. The traditional method is difficult to achieve uniform vulcanization of the whole product. Microwave rubber vulcanization equipment design, microwave heating is only used to rapidly warm up to a predetermined vulcanization temperature of a section of the interval, has reached the vulcanization temperature, immediately after the traditional heating method for insulation, so that the arrangement, microwave rubber vulcanization equipment, not only to speed up the production time, saving energy, but also to get the effect of uniform vulcanization treatment, improve product quality. Again, such as microwave high-temperature sintering of ceramics research work shows that the microwave high-temperature method of heating fast, can shorten the production time, improve the quality of ceramic products. But the experimental study of the sintering process firing rate is low, it is difficult to grasp the rapid warming of all aspects. Calm thinking, improve the process of ceramic sintering, but also should be conventional heating and microwave heating combined method, the initial heating do not have to use microwave methods, to reach more than 500 ° C, (ceramic billet absorption of microwave energy coefficient by the temperature increase and improve), at this time, the microwave method can be billet inside and outside the same sintering temperature, and heat preservation, cooling is still the use of conventional methods. This idea and see the report coincides, foreign countries have been in this idea under the premise of the development of small-scale microwave sintering and conventional sintering combined with the conveyorized kiln, and got a very good sintering results. The use of microwave power to carry out a number of scientific research, in fact, in the search for related multidisciplinary laws on the convergence of efforts. Microwave power engineering technical work, is accumulating experience, and gradually explore and related applications to match the discipline, in different areas **** with the same to find ways to overcome the difficulties of the research work, so that the various high-tech research into the industrialization of the transformation as soon as possible. 6. Microwave and traditional heating and drying technology, large-scale microwave power application equipment is mainly used in the production of heating and drying and food plus. But from the demand situation, microwave power application equipment has not been able to meet the needs of a number of fields. Due to the popularity of household microwave ovens, many enterprises to improve the intention of production has been made in the household microwave ovens in the feasibility of the test, or have seen the improvement of the omen, need to further facilitate, but the existing microwave power equipment and may not be fully adapted to these requirements, that is to say, in terms of microwave heating and drying, the microwave power engineering is still there is still a lot of pioneering work can be done. These areas are roughly non-metallic materials, high-temperature treatment, polymer heat-setting, chemical materials, absolute drying, de-crystallization of water, glass fiber drying, a variety of biochemical materials, food, low-temperature drying, vacuum dehydration drying. Some areas of heating and drying, traditional methods have been carried out a lot of research work. For example, drying methods, focusing on the most effective in different states of the moisture channeling discharge, spray drying, vulcanization bed drying, vibration vulcanization bed drying, Teng drying, vacuum drying should be different states of the material and the hot air carve points in contact with the phase and discharge of moisture. If the appropriate introduction of microwave energy, it is entirely possible to speed up the drying process, and improve the drying quality. These areas of microwave methods are appropriate to combine with traditional methods to supplement to the material to provide insufficient heat to the weakness of the microwave heating can be used. The method of evacuating moisture, should also use the advantages of traditional methods, which requires reform of the original equipment, in order to be compatible with the feed into the microwave power and measures to prevent microwave leakage. Adiabatic treatment of many materials, and non-metallic materials in the application of heat treatment, large-scale microwave power equipment density is not high enough, the design of high field density equipment, there is a deterrent microwave power equipment can improve the heat treatment of non-metallic materials, from the theoretical estimation of the chemical materials, adiabatic treatment will achieve good results. Unified electromagnetic field power engineering methods to improve production conditions for the progress of cutting-edge research efforts from many reports in the literature, foreign radio-frequency heating equipment design method to be gradually and microwave power close to the development of the so-called 50 Ω radio-frequency industrial heating technology, the standard radio-frequency equipment should be composed of the following four parts: (1) with a 50 Ω output impedance of the radio-frequency oscillator; (2) linking the radio-frequency Oscillator and match box 50Ω coaxial line; (3) with control and discriminator discrimmatic match box; (4) applicator. That is to say, the direction of development of RF power equipment is no longer a unified body of equipment, but also can be assembled with general-purpose parts of the equipment, and will be oscillating source and applicator can be as needed to pull the distance (the current f-industrial equipment is simply not able to meet this requirement). Such a method of work, in fact, and the development of microwave power equipment is consistent with the method; that is, the method of assembling equipment according to standardized parts. At the same time, the RF power output is proposed to change the crystal feed into the amplifier, in order to stabilize the frequency and control power; such a program and further improve the microwave power source; application of orthogonal field amplifiers, active microwave networks composed of oscillator circuits known as frequency stabilized tube (Stabilotron) is consistent with the idea. Stabilotron output power at 2450MHz is 10-50KW and 10-100KW. typical Rf use frequency is 13.56MHz, 27.12MHz, 40.68MHz at present there is a tendency to improve the use of the frequency, the trial Klystron using 267MHz as the High power industrial applications, and microwave power applications are 2450MHz, 915MHz, to the development of 434MHz trend. On the equipment design method from the point of view, RF equipment and microwave equipment is gradually approaching, while the microwave frequency in the downward expansion, RF frequency in the upward. That is, the two up and down the extension, and further linked into a unified electromagnetic field power equipment, in fact, microwave power equipment and radio frequency power equipment is electromagnetic field power equipment of the two leaves, should be used in electromagnetic field power application of a unified point of view to deal with the program, radio frequency and microwave have their own specialties, each has the shortcomings, should be used in its long, to avoid the shortcomings of their own, so that the electromagnetic field of the country's electromagnetic field power equipment to make a more reasonable and closer to the practical. Microwave and radio frequency electromagnetic field power engineering work is mainly in the field of heating and drying, material processing and gas discharge, the application is very wide, very close to the actual production, both on the traditional heating and drying method of improvement, but also many important research methods of the current important tool. At present, it should make some overall planning on the basis of investigation and research. Which industry heating and drying there is a weak link, electromagnetic field power equipment should be what frequency band using which technical means to deal with these links are more reasonable. The current use of radio frequency and microwave methods of cutting-edge research work, the weak links of the equipment base what problems exist, should gradually strengthen the infrastructure to strongly promote cutting-edge research work.