Design And Research Of Multi-channel Temperature Controller Based On ARM

We can hardly get accurate mathematical models of temperature because of its uncertainty of structure and parameter, as well as its feature of great delay and coupling of variable.This thesis is doing a research on a new control method on the basis of the problems mentioned above, aiming to get better control effect than that controlled by regular controlling method in the aspect of settling time, overcome shoot and steady-state error. What's more, this new control algorithm is to be applied on the microprocessor and designing a temperature control equipment based on ARM, so as to satisfy the needs of the market on goods with multi-channel , intelligent, full of communicate interfaces .The thesis firstly gives an introduction of the history and present research of the temperature control both at home and abroad, and then brings forward a design of Expert-fuzzy PID control algorithm and also gives Matlab-Simulink simulation. The control algorithm is in response to the features of temperature and based on the compromise of advantage of controlling strategies, including PID control, fuzzy control and expert control. The control algorithm overcomes the effect of temperature delay due to its"pre-control"which we can see from results of the simulation. Further more, the control algorithm gives a more ideal performance compared to the regular temperature control method.Analyzing the principle of operation and functional requirement of the temperature controller first, the thesis gives the circuit design of hardware and implementation of software. The system hardware is consisted of core controller including MiniARM Card for Industrial Computer M2005-NU11, surrounded by temperature signal acquisition and collecting module, human-machine interaction module, data storage module and communication module. The part of software is supported by the embedded operating systemμC/OS-II, designed according to the system structure of the embedded soft ware equipment driver, operating system and application software.The multi-channel intelligent temperature controller based on ARM displays through LED and the graphical user interface makes human-machine interaction very easy. The experiment results show that the multi-channel temperature control with a accuracy of 0.5℃can be realized by the Expert-fuzzy PID. The controller has several communication interfaces, following ModbusRTU and ModbusTCP protocols, so it can be widely applied in industrial control process.