What are the aspects of energy saving and environmental protection of intermediate frequency power supply?
Author： Source：TENYES ELECTROTHERMAL EQUIPMENT CO.,LTD. Date：2020-09-29
Because the principle of medium-frequency induction heating is electromagnetic induction, and its heat is generated in the workpiece itself, ordinary workers can work continuously for forging tasks ten minutes after working with the medium-frequency electric furnace, and professional workers who burn the furnace do not need to burn and seal the furnace in advance.
Because of the rapid heating speed, there is little oxidation. The oxidation loss of forgings heated by medium frequency is only 0.5%, which is 2% in gas furnace and 3% in coal furnace. The intermediate frequency heating process saves materials, and at least 20-50 kg of steel raw materials are saved per ton of forgings compared with coal furnace. The material utilization rate can reach 95%. Because the heating method is uniform and the temperature difference between core and surface is extremely small, the service life of forging die is greatly increased in forging. The roughness of forging surface is less than 50um, which saves energy by 31.5% ~ 54.3% compared with oil heating and 5% ~ 40% compared with gas heating. Good heating quality can reduce the reject rate by 1.5%, increase the production rate by 10% ~ 30% and prolong the die life by 10% ~ 15%.
Compared with the coal stove, the induction heating stove with superior working environment, improved workers' working environment and company image, no pollution and low energy consumption after installation of medium-frequency power supply can prevent workers from being baked and smoked by the coal stove under the scorching sun, and can meet the requirements of various indexes of environmental protection departments, and at the same time establish the external image of the company and the future development trend of forging industry. Induction heating is the most energy-saving heating method in electric heating furnace. The power consumption of tons of forgings heated from room temperature to 1100℃ is less than 370 degrees.
Series inverter intermediate frequency power supply adopts "series inverter thyristor intermediate frequency power supply technology". Although thyristor fully-controlled rectifier furnace is adopted, it is not used to regulate voltage, but only used to realize soft start and act as electronic switch in case of fault, and quickly cut off power supply. During normal operation, thyristor is always in full conduction state, so as to make the power supply of power grid have high power factor and reduce harmonic interference. The rectifier control circuit adopts digital shift trigger circuit. Digital shift trigger circuit has many advantages, such as good repeatability, good stability, good symmetry, strong anti-interference ability, convenient debugging, etc. If digital quantity is given, remote control can still be realized. Advantage efficiency is high, series inverter adopts half-bridge circuit, the number of main circuit components is relatively reduced, and it has high power factor, so it has high power. Good starting characteristics, can start at will under full load and heavy load, and the success rate of starting is 100%. Improve the power factor to ensure that the power factor reaches 95% at any power. Constant power output, with constant control of power output. In the smelting process, when the load and temperature change, the load is always full of power output, thus shortening the smelting time. Have perfect protection and operation monitoring system. For example, sensors are used to take signals of incoming line current, voltage, channel current and voltage, and double closed-loop digital circuits are repeatedly protected by current limiting, voltage limiting and excessive overvoltage, with water temperature and water pressure protection, etc. KK SCR and KP SCR have self-turn-off time protection. There is a complete detection system to monitor the working temperature of inverter and filter capacitor with temperature switch meter. Once the cooling water temperature exceeds the set value or there is a waterway fault, it will give an alarm and cut off the power supply. The cooling water input of power supply is controlled by hydraulic relay, and the cooling water output is monitored by temperature switch meter, which will give an alarm and cut off the power supply.