Thermal-force control ability under variation of electromagnetic stick structure parameters in RPECT

Thermal-force driving of roll profile electromagnetic control technology (RPECT), which can be used to adjust the roll profile, can be affected by the sequential temperature rise between the electromagnetic stick (ES) and electromagnetic control roll. Due to the limited space of ES and induction coil, the cross-sectional area of induction coil can be inevitably affected by changing the size of the ES induction zone, which can further change the energy input under the same electromagnetic parameters, the temperature rising effect and the bulging ability. To investigate this phenomenon, the effects of the radius of the induction zone on the thermal-force contribution ratio, the heating ability of ES and the temperature distribution were analyzed through an electromagnetic-thermal-structural finite element model. To ensure that the results are applicable to RPECT, the thermal energy conversion ability and thermal-force roll crown control ability under different lengths of the induction zone were analyzed. It was found that whether the current density regulation mode or the current frequency regulation mode is adopted, the cases with 20 or 25 mm radius of the induction zone have the great thermal energy conversion ability and the good thermal-force roll crown control ability. The reasonable adjustment of the length of the induction zone can reduce the radius required for the maximum energy efficiency regulation. Combined with the results of the simulation analysis, the optimization of ES based on the control ability maximization requirement is achieved, which provides the base for the design and configuration of ES in RPECT.