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    Principle of medium frequency induction heating

    When the magnetic flux surrounded by the conductor loop changes, the induced potential will be generated in the loop. Similarly, the conductor in the alternating magnetic field will also generate induced potential under the action of electromagnetic induction, and an induced current (eddy current) will be formed in the conductor. The induced current will overcome the resistance of the conductor itself and generate Joule heat, which will heat the conductor itself, make it heat up and melt, and achieve various hot working purposes. This is the principle of intermediate frequency induction heating. Advantage of medium frequency induction heating Heating speed is fast Oxidative decarbonization is less because the principle of medium-frequency induction heating is electromagnetic induction, and its heat is generated in the workpiece itself. Because of the rapid heating speed, there is little oxidation, high heating efficiency and good process repeatability. Heat evenly High temperature control precision induction heating is easy to realize the requirements of uniform heating and small temperature difference between core and surface. The application of temperature control system can realize the accurate control of temperature. Compared with other heating methods, induction heating with low energy consumption and no pollution has high heating efficiency, low energy consumption and no pollution; All indexes can meet the requirements of users. Under the condition of diathermy, the power consumption of heating from room temperature to 1100℃ is less than 360. The relationship between induction heating coil and heated object (metal) is the same as the relationship between primary and secondary coils of transformer. Magnetic lines generated by passing high-frequency current through the heating coil are concentrated on the heated object, and eddy current is generated by electromagnetic induction to heat the heated object. At this time, by selecting appropriate frequency, power, heating time, holding time, coil shape, etc. of AC current according to the type and shape of steel, all kinds of steel can obtain appropriate quality characteristics. Application of Medium Frequency Induction Heating 1. Before forging, hot extrusion, hot rolling, blue brittle blanking and other blank diathermy. 2. Heat treatment, including quenching and tempering of parts. 3. Brazing 4. Smelting black, colored and rare precious metals 5. Sintering refractory metals such as tungsten and molybdenum at high temperature, powder metallurgy etc. 6. Stable power supply for drawing monocrystalline silicon. Working principle of medium frequency induction heating power supply According to the electrician principle, the conductor in the alternating magnetic field will generate induced electromotive force, and then turn into eddy current to cause the conductor material to heat up. The medium-frequency induction heating power supply is a device that converts three-phase power frequency (50 HZ) alternating current into single-phase medium-frequency alternating current. Series resonance is adopted in the medium frequency induction heating power supply, that is, voltage type resonance frequency tracking. Therefore, the efficiency is higher and the power factor is higher. Therefore, it has obvious power saving effect, and the electricity consumption per ton of bar material is 341 degrees. Working principle of medium frequency induction heating power supply At present, the working principle of medium-frequency induction heating power supply, which is widely used, is that three-phase alternating current is rectified into adjustable direct current by rectifier circuit, which is filtered by reactor and then converted into alternating current with higher frequency by inverter to supply load. The front stage of the intermediate frequency induction heating power supply can't be controlled by full bridge rectification, which will not cause waveform deformation in the rectification section, and has no clipping phenomenon related to broken angle. Moreover, it uses a large capacitor to filter, so the harmonic number is small and the interference to the power grid is small. With the rapid development of China's industrialization process, the field of induction heating is also developing rapidly. Due to the environmental protection requirements and coal price, coking coal heating not only does not meet the environmental protection requirements, but also is very uneconomical in price and economy. On the other hand, industrial heating also uses a large number of KGBS medium-frequency heating equipment with thyristor as the main device, which consumes a lot of electric energy with low power factor. With the financial crisis spreading, it saves energy and reduces consumption. Cost reduction has become a very urgent problem for small and medium-sized enterprises, so we have successfully developed JZ(IGBT) series energy-saving intermediate frequency with nearly 20 years' experience in induction heating. Characteristics of intermediate frequency induction heating power supply 1. Constant power output to ensure 100% utilization of power transformer capacity. 2. The power factor is always greater than 0.96, and there is no high-order harmonic interference and no pollution to the power grid. 3. Digital phase-locked technology is adopted, which has high frequency stability. 4 has multiple protection functions. 5 The advanced multi-frequency preset technology has a successful start-up rate of 100%. 6 Adopt totally enclosed internal circulation water cooling system to ensure equipment safety.
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