| With the continuous development of the measurement and control industry,the controlled system and the controlled object are becoming more and more complicated.As an important detection parameter most commonly used in the measurement and control industry,temperature is very important for the research on temperature control and acquisition.Guiding significance.Especially in the high temperature target chamber environment,the electromagnetic induction heating technology can make the temperature meet its requirements and can significantly improve the performance of the system,and realize the material impact test,which is also one of the important topics in the current scientific research field.This article takes the heating of high-temperature target as the background,establishes an accurate heat balance model of electromagnetic induction heating system,and controls the temperature of the heated sample,so that the sample is quickly heated and accurately stabilized to the target temperature.In the high temperature target chamber environment,there are many uncertain factors such as nonlinearity,time lag,disturbance,etc.in the sample heating process,which makes the electromagnetic induction heating system control the sample temperature measurement inaccurate and it is difficult to make the heated sample quickly track the target.For the temperature problem,the improved PID control algorithm estimated by Smith has been studied to solve such problems.Finally,the design and realization of the electromagnetic induction heating temperature measurement and control software is completed through the LabVIEW virtual platform.This article mainly completes the following research work:1.Combined with the actual high temperature target chamber environment,create a simulated target chamber test chamber,based on electromagnetic induction heating theory,heat the sample uniformly at high temperature,simulate the electromagnetic induction heating process through MATLAB,and finally establish the thermal balance model of the electromagnetic induction heating system.2.In order to avoid large fluctuations and overshoot problems in the temperature curve of the sample measurement,this paper studies and improves the Smith estimation algorithm and PID control algorithm.The idea of Smith algorithm is to automatically predict and compensate the time-delay system,so as to offset the hysteresis characteristics of the system.Faced with the disturbance problem caused by the sample heating itself and the thermocouple contact temperature measurement,this article chooses to further improve the Smith predictor,adding a link to its predictor to realize the anti-disturbance function.The improved Smith predictor can be combined with PID control to get an improved Smith-PID control algorithm.Finally,under the electromagnetic induction heating system,the algorithm is compared with the standard PID control algorithm and the tracking differentiator PID control algorithm.The results show that the improved Smith-PID control algorithm has strong resistance in the thermal balance model of the electromagnetic induction heating system.Disturbance capability and hysteresis compensation performance to achieve the expected results.3.With LabVIEW as the software development platform,the electromagnetic induction heating temperature measurement and control software is designed.The software realizes real-time monitoring of electromagnetic induction power supply equipment,and at the same time collects temperature data.Finally,through software testing,the practicability and reliability of the software are determined. |
