Modeling and observer design of an inductive oven with continuous product flow

A control-oriented model of an inductively heated continuous industrial wafer baking oven is derived. The periodic motion of the baking plates leads to a special structure, which can be exploited to transform the timevariant model into a time-invariant discrete-time model. Emissivities of individual baking plates are uncertain
and affect the pyrometric temperature measurements. Therefore, a state observer which also estimates this influence on the measured temperature is designed. The feasibility of the proposed concept is shown by measurement results on an industrial wafer baking oven.