Patent ID: 9060389
Filing Date: 2015-06-16
Classification: H05B

Abstract:
1. An induction heating cooker, comprising: a plurality of heating coils; a plurality of auxiliary switching elements connected to the plurality of heating coils, respectively, and performs bidirectional conduction when turned on; a first main switching element and a second main switching element, configured to generate a high-frequency voltage by alternately switching, and selectively apply the generated high-frequency voltage to the plurality of heating coils; and a control unit configured to determine heating coils, on which a container is positioned, based on current flowing through the plurality of heating coils, to perform a time divisional control on auxiliary switching elements, which are connected to the determined heating coils, among the plurality of switching elements such that the auxiliary switching elements connected to the determined heating coils are sequentially switched on, and alternately switch on the first main switching element and the second main switching element during each of on-times of the auxiliary switching elements subject to the time-divisional control such that power levels of the determined heating coils are controlled, wherein a duty ratio of a pulse width modulation signal of the first main switching element or the second main switching element that is switched on is controlled to vary, and wherein switched-on auxiliary switching elements among the plurality of auxiliary switching elements allow current caused by the high-frequency voltage to flow therethrough such that current due to a high-frequency voltage applied by the first main switching element is different from a direction of current due to a high-frequency voltage applied by the second main switching element to vary a direction of current flowing through a heating coil connected to the switched-on auxiliary switching element.