High-frequency heating apparatus for maximizing input current while securing a uniform margin relative to the cutoff current

摘要

A high-frequency heating apparatus is designed to maximize the input current while securing a uniform margin relative to the cutoff current, thereby enabling maximized and efficient output of high-frequency waves. The high-frequency heating apparatus includes: a power supply unit; an input current detector; a power converting unit for converting the power from the power supply unit into high-frequency waves; an inverter controller for controlling a semiconductor device; a magnetron for radiating electromagnetic waves; and a circuit for implementing negative feedback control, in the inverter control circuit, of the output from the input current detector. The apparatus further includes a control circuit having a microcomputer for outputting signals to the inverter controller so as to control the input current such that the input current characteristic of the high-frequency heating apparatus will approximate the current cutoff characteristic of the overcurrent circuit breaker with respect to the elapsed time.