New induction heated fluid energy conversion processing appliance incorporating auto-tuning PID control-based PWM resonant IGBT inverter with sensorless power factor correction

This paper describes a newly-developed prototype of an electromagnetic induction flow-through metallic package-in-nonmetallic pipeline type fluid heating appliance, which is composed of series-resonant phase-shift PWM inverter using IGBT modules in addition to an auto-tuning PID controller based on feedback implementation. This inverter-fed fluid heating appliance is to be more acceptable for high-quality heat transfer and delivery processing under a precise temperature management, as well as heat-energy storage and heat exchange processing plants as vessel and tank fluid heating in the pipeline systems, because of clean processing, high-efficient, compactness in volumetric size, high-reliability and best-matched control ability. In particular, the series resonant PWM IGBT inverter system with a power factor correction and active sinewave line current-shaping functions is introduced. The inherent new structure is proposed from a practical point of view, in which specially-designed flow-through induction-heated metallic package assembly to induce the eddy currents with a large heating surface is incorporated into the nonmetallic cylinder or tank with a working coil connected to a high-frequency inverter. The remarkable features of this inverter-fed fluid-heating appliance are presented as compared with the conventional electrical heating methods. Its operating characteristics in steady-state are illustrated and evaluated in experiment and computer simulation results. The promising applications of this fluid heating appliance are mentioned in this paper