Robust Features of SOSMC Guides in Quality Characterization of Tank Circuit in Air-Cooled Induction Cap Sealing

Induction cap sealers are actively controlled passive component dominant industrial power control equipment. In series resonant inverter-fed air-cooled induction sap sealer, the major part of power loss takes place in high-current passive tank circuit. To enable power transfer to mobile aluminum foil as and when needed, the tank circuit remains energized at rated current. Efficient power delivery to load needs minimum power loss in them. Litz-wire-based air-cooled system, to a large extent, meets this criterion. Further improved performance depends on optimal choice of passive components in the tank circuit. In addition to that, the quality and reliability of the controller depend on electrical and thermal stresses in each of them. At no load, the poor damping factor of litz-wire-based tank circuit tends to generate oscillatory current envelope resulting in increased power loss in tank circuit, as well as in increase e in voltage stress in resonant capacitor. Robust second-order sliding mode control is able to eliminate those problems. This paper further elaborates that the robust power control feature of second-order sliding mode control could uniquely be used to qualitatively differentiate among possible alternates of each constituent member of tank circuit.