Temperature and Voltage Control Methods of Power Regulators Based on Inverter for Heat Treatment

In a heat treatment system, the heater temperature is stably controlled to its reference value, while limiting the voltage across the heater to 60 V for safety. In order to achieve the requirements of the heat treatment, this paper proposes the method to control both the heater temperature and heater voltage for heat treatment by using two types of power regulators such as a high-frequency transformer and inverter system and a single-phase PWM inverter system. Both the hysteresis on-off control of the heater temperature and the open-loop heater voltage control for two power regulators are suggested in order to improve the performance of the heater temperature and voltage controls while ensuring safety. Experimental results are demonstrated for validating the performances of proposed control strategies of two power regulators.