resumo
- This paper deals with the modelling and control of an oven for reflowing electronic surface-mounted devices. The modelling is done taking into account that the system has a second-order dynamic behaviour whose parameters were obtained through a genetic algorithm. It is also shown that this system exhibits a high pure time-delay which makes the design of the control system very difficult. In particular, the performance of a PI controller is evaluated with respect to tracking two different types of reference signals. It is observed that the performance of such a controller is severely affected by the huge inertia of the system. In order to mitigate this effect, tests were performed with a different architecture known as the Smith predictor. It is concluded that, although with differences, neither the PI controller nor the Smith allows the tracking of the typical reference in a reflow process.