Vacuum Sintering Furnace for Powder Metallurgy
In view of the time-varying, large lag and non-linear characteristics of vacuum sintering furnace of powder metallurgy, the PID control effect is not ideal, and the fuzzy control algorithm is selected. The simulation models of PID control and fuzzy control are established and compared. The results show that the response speed of the system is very fast, the steady-state time is only 3.2s, there is no overshoot, the steady-state error is 1.2 C, and the steady-state accuracy is very high. The output of the system simulation is close to the given input waveform, the system regulation time is short, the system quickly enters the stable state, and the oscillation is very small. Fuzzy control is superior to traditional PID control and can meet the temperature control requirements of vacuum sintering furnace of powder metallurgy.
Powder metallurgy vacuum sintering furnace is a time-varying, large lag, non-linear heating system. Because of the complexity of its physical and chemical mechanism, there are many influencing factors, it is difficult to obtain accurate mathematical model. When the parameters change greatly and the control precision is required high, the general PID control effect is very unsatisfactory. Fuzzy control does not require the system to give an accurate mathematical model. According to the actual experience of human beings, control rules are formulated and control decision tables are made. The system is controlled according to the decision tables. It is especially suitable for sintering furnace, which is a complex industrial production object. The main factors affecting the quality of products in sintering process are sintering temperature and sintering time. Especially the requirement of temperature is very strict. The temperature difference is generally not allowed to exceed the given value of ~3 ~5 C, so it must be strictly controlled.