Predictive decoupling control for vacuum heat treatment furnace

The accurate control of the heat treatment temperature is a complex decoupling control problem in vacuum heat treatment furnace. In order to control the heat treatment temperature accurately, the second order plus time delay models of every temperature region is identified. It based on the date from the vacuum heat treatment furnace. A new predictive function decoupling control(PFDC) method is proposed. This method can decompose the decoupling control problem of an multiple input multiple output (MIMO)system into predictive function controls (PFC) of several single-input-single-output (SISO) systems. The decentralized optimization method is adopted to deal with coupled variables instead of the whole optimization. Utilizing the characteristics of PFC, the introduced base functions increase freedom of design, reduce the online calculation amount significantly, and thus efficiently simplify parameter design and the calculation load. Then, an analytical control equation can be derived from the PFDC method. The simulation and practice application results show that the PFDC is better than the tradition or modified PID control system. It is efficient and effective.