Patent ID: 6965100

Claim:
A method for controlling output power of a combination hood and microwave oven including a vent fan for ventilation, a high voltage transformer configured to generate high voltages having different magnitudes at a secondary side of the high voltage transformer within a range of power consumption of the microwave oven, a magnetron for outputting high-frequency waves with the high voltages induced at the secondary side of the high voltage transformer and a plurality of switches for controlling current passages at a primary side of the high voltage transformer by differently controlling the number of windings at the primary side of the high voltage transformer, comprising: the first step of selecting a cooking menu; the second step of determining whether the vent fan is operated; and the third step of operating a switch for a first high, maximum output level of the high voltage transformer when the vent fan is not in operation but another switch for a second high output level lower than the first high output level of the high voltage transformer when the vent fan is in operation, wherein the third step is performed while monitoring the operation of the vent fan during a predetermined cooking time for the selected cooking menu.