Page - (000007) - in Adaptive and Intelligent Temperature Control of Microwave Heating Systems with Multiple Sources

Forewordof theEditor Microwave heating is becoming popular in industrial processes. Dif- ferent toconventionalheatingtechniques (e. g. hotair, infrared light), the microwave heating principle is volumetric, which means the mi- crowave penetrates through the object and is heating its volume uni- formly. Hence, both surface and interior of the object are heated si- multaneously,whichresults insignificantlyreducedprocess timeand energyconsumption. However, the microwave heating is not always uniform. Unlike in convectional heating where the temperature distribution is reaching equilibrium after a certain process time, the temperature distribution of microwave heating is varying during the entire heating process. There are a number of spatially distributed hot spots and cold spots, caused by not only the properties of the workpiece, but also the elec- tromagnetic (EM)fielddistributionwithin theovenchamber. Inhiswork,Dr.-Ing. YimingSunproposesaninnovativereal-timemi- crowave control approach to improve the temperature homogeneity under microwave heating by combining the idea of advanced control algorithms and multi-source microwave feeding systems. In this ap- proach, Dr.-Ing Yiming Sun develops multiple adaptive or intelligent controlstructures, includingthemodelpredictivecontrol (MPC),neu- ral network control (NNC) and reinforcement learning control (RLC) methods, to automatically adjust the power of spatially distributed feeding antennas, in order to actively influence the electromagnetic (EM) field distribution inside the oven chamber, and hence, improve the temperature distribution. The experimental results prove that these advanced control methods can effectively reduce the final tem- peraturederivationsandimprovethetemperaturehomogeneity,com- paredwithconventional feedbackcontrol strategies.