Energy saving management of medium frequency furnace

Medium frequency electric furnace is an electromagnetic induction heating equipment, and it is also a large electrical equipment. The heating power of medium frequency electric furnace generally ranges from 100kW to 10000kw. Therefore, the importance of energy saving for medium frequency electric furnace is self-evident, so how to carry out energy-saving management for medium frequency electric furnace?

1. First of all, we need to consider the matching of the heating power of the medium frequency electric furnace. This problem seems simple, but in fact, many customers who use the medium frequency electric furnace have not been able to control this aspect very well. The matching of heating power of medium frequency electric furnace is that the power of medium frequency electric furnace is consistent with that of actual metal material heating, and there is no phenomenon of big horse pulling cart or small horse pulling cart. If the power of medium frequency electric furnace is greater than the required heating power, if the furnace is in half power operation, the harmonic and reactive power increase, and the power consumption increases; If the power of medium frequency furnace is less than the required heating power, the heating efficiency is reduced, which is equivalent to the state of boiling oil, and the power consumption is increased for no reason. Therefore, the power of energy-saving medium frequency electric furnace should match the heating power.
2. The power supply design of energy-saving medium frequency electric furnace is different from that of ordinary medium frequency electric furnace. The energy-saving medium frequency electric furnace adopts series resonant medium frequency power supply, and its power factor can be guaranteed above 0.95. Moreover, the output power of medium frequency electric furnace is always full power output, and there is no phenomenon of horse pulling trolley or small horse pulling cart.
3. There are certain requirements for heating frequency and incoming line voltage of energy-saving medium frequency electric furnace. The frequency of medium frequency electric furnace has a great relationship with the diameter of heated workpiece. If the frequency of medium frequency electric furnace is too high, the heating time will be prolonged, the heat loss will be increased, the thermal efficiency will be reduced, and the heating efficiency will also be reduced, which will increase the electric energy cost of medium frequency electric furnace. Large diameter, low frequency, small diameter and high frequency are the general requirements of medium frequency electric furnace; Increasing the inductor terminal voltage of medium frequency electric furnace will increase the number of turns of induction coil, reduce the current on the induction coil, reduce the power loss, and improve the efficiency of medium frequency furnace inductor. Increasing the terminal voltage of inductor is a better way to save energy. The induction heating mode with low voltage and high current should be avoided as far as possible.
4. If there are 3% impurities on the surface of metal materials heated by medium frequency electric furnace, it will cost 3% more electric energy to melt these impurities, which will also affect the service life of medium frequency furnace lining; The test results show that the electric efficiency and melting quality of the medium frequency furnace are generally 200-300 mm. If it is too long, it is easy to build a bridge in the furnace, which will affect the heating speed and waste energy. This is also the key point of energy saving medium frequency furnace.
5. The induction coil design of energy-saving medium frequency furnace is also the top priority of medium frequency furnace energy saving. If the induction coil density of medium frequency furnace is high, the power loss will increase, and the electrical efficiency of medium frequency furnace inductor will decrease. Therefore, the section size of pure copper tube of medium frequency furnace induction coil depends on the number of induction coil turns and the geometric size of medium frequency furnace inductor. In this way, the inductor coil of medium frequency furnace largely determines the energy-saving effect of medium frequency furnace.

To sum up, in order to realize the energy-saving control of intermediate frequency furnace, it is necessary to carry out all-round management, and consider the energy-saving effect of intermediate frequency furnace from the design, manufacture and use of intermediate frequency furnace, so as to ensure the real energy-saving of intermediate frequency furnace.