| Heat exchangers are the process equipments for exchanging the heat quantity. They were widely applied in the field of dynamical engineering and some other processing industrial departments. Accurate measurement and effective control of the output medium temperature are important conditions of high quality and production, energy-saving, and safety in the process control system of heat exchangers. Therefore, the control to output water temperature in heat exchangers is a key issue to industrial process. This paper studies the control to gas-to-liquid heat exchanger. The control task is to control the temperature of output water from the heat exchanger in order to maintain the required value by adjusting the flowrate of heat carrier (steam), and to improve the quality of output water to ensure the quality of production as well as to make full use of the energy source.Presently, the traditional PID control is adopted mostly in the systems to control the output water temperature of the heat exchanger. However, because the heat-exchanging system has nonlinear characteristics of pure lag, great inertia and parameter time-varying, the traditional PID control sometimes can not meet the requirement of static and dynamic characteristic. A kind of advanced control method should be approached.In the control to output water temperature of heat exchanger, based on the structure and principle of the fuzzy controller, the paper discussed the influencing factors of system performance and improved the key links of the basic fuzzy controller. Then an intelligent integral fuzzy controller based on self-adjustment and weighted factor was proposed, whose regulation adopted the analytic expression with weighted factor and introduced the intelligent integral module. The simulated experiment in MATLAB\SIMULINK demonstrated that this controller not only improved the static and dynamic performance of the control system, but also possessed some advantages of such as simple structure, less parameters need to... |
PDF Full Text Request