Fault Tolerant Control Design And Simulation Of Batch Reactor

Fault-tolerant control technology is an interdisciplinary study. Its theoretical basis involves the modern control theory, pattern recognition, artificial intelligence, signal processing and corresponding science. Its appearance and the development are the result of Alternate effects by the development both in practical applications demand and the multidisciplinary theory. Fault-tolerant control technology provides new ways to the reliability and security of modern industrial control which becomes more and more complicated and extended gradually. For this sake, the development and the research in the fault-tolerant control program of industrial production make a great significance.Starting with temperature control of the Vessel proceeding Batch Reactor, this paper makes a further studying in condition of using cascade control to the reactor temperature as the master sensor fails to work.Firstly, a model identification method is introduced systematically, proposing a mathematical model method. This method covers a way to identify the construction of mathematical model by a use of single variable affecting the relationship between linear superposition, and it also refers to the Least-squares method to the identification of model parameters. According to the characteristic of the reactor, Jacket temperature, cooling water temperature and the cooling water flow are selected as input, Kettle temperature as output. With the combination of curve fitting and least-squares method, the algebraic model with three-input single-output under open-loop system is established. For the sake of simulation comparison, the object (reactor) features is identified by using two-stage stochastic gradient algorithm according to the data extracted under laboratory in the process of the closed-loop system.Secondly, this paper discussed the basic fault-tolerant control methods. An active fault-tolerant control program, using signal reconstruction to achieve a cascade control as sensor fails to work in the main control with proceeds mathematical mode, is designed based on the principle of state observer. In the stimulation from fault detection unit, the feedback controller, with the inputs from the mathematical model estimates instead of the inputs from the master sensor, can makes the systems in the normal operation.Finally, the simulation results show that, when the measurement of certain components in the system fails to work, leading to the lost of control signal, the assumptions to realize the system Fault Tolerant Control through the use of results calculated by the system model is totally feasible.