Design Of Control System For Temperature Of The Electricity Heating Furnace

Along with our country economy's fast development, the energy consumption grows day by day. How to reduce the power loss to raise the economic efficiency, has become the people matter of concern. For example in the metallurgy profession steel rolling production process, the heating furnace energy consumption approximately composes the entire factory total energy consumption about 60%,which is the steel rolling working procedure energy consumption wealthy and powerful family. Particularly in the recent 20 years, heating furnace's hardware equipment level had the very big enhancement, therefore raises the heating furnace operational level, realizes the computer completely automatic burnt steel and reduces the heating furnace energy consumption significance to be very big. The traditional electric heating stove's temperature control has the elevation of temperature unidirectivity, big inertia, big lag, when characteristics and so on denaturation. Its elevation of temperature, the heat preservation are depend upon the resistance wire heating, the temperature decrease depend upon the environment natural cooling. When its temperature, once the over modulation is unable with the control method to cause its temperature decrease, thus very difficultly with the mathematical method establishment precise model and the fixed parameter, the application tradition's control theory and the method achieves the ideal control effect with difficulty.This article is in does not have the useful mathematical method establishment precise model and in the parameter situation, establishes take the electric heating stove as the object of study, in view of the electric heating stove's characteristic, designed has controlled heating furnace's furnace temperature with the computer control system.This article heating furnace computer control system is mainly which by the thermo-couple metering circuit, the cold end compensating circuit is composed signal input the electric circuit and by CD4051, ICL7135 and so on control circuit constitution which is composed. The first input circuit carries on gathering to the temperature signal to enlarge, then escorts to this signal multi-channel multiplexer/divider CD4051, carries on the choice under monolithic integrated circuit's control to the thermo-couple metering circuit signal, and carries on after a/D switch transforms the digital signal. The thermo-couple metering circuit is mainly is composed of the OPA2335 amplifying circuit and the system cold end electric circuit, uses the system cold end electric circuit is mainly considers the external environment temperature to the signal gathering influence. In the control circuit, considered monolithic integrated circuit W77E58 and ICL7135 have the very big disparity in the signaling frequency, must therefore add on the 74HC161 frequency divider to carry on the frequency division. In order to facilitate the human to understand fast promptly heating furnace's working condition control circuit part must have with the outside connection, the interface circuit is composed of MAX232, like this achieves the manual control through the peripheral device.This electricity heating furnace temperature control system's intelligent control system, has satisfied the temperature control stable request, reduced the personal error which operators' labor and brings, improved the product heat treatment quality.