| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an ohmic-heating device with high efficiency and low power consumption. <P>SOLUTION: A heating power supply 100 is provided with a three phase bridge rectifier circuit 104 for rectifying a three-phase alternating current, a primary side resistance 106 smoothing a rectified wave by the three phase bridge rectifier circuit 104 and a primary side capacitor 108. In a post-stage of the rectifier, a step-down chopper circuit 109 comprising a power module 110, a feedback diode 112, a secondary side inductor 114 and a secondary side capacitor 116 is provided. In a post-stage of the step-down chopper circuit 109, a single-phase inverter 118 comprising four power modules 128, 130, 132, 134 comprising IGBTs and feedback diodes is provided. The single-phase inverter 118 is made to output arbitrary output voltage by performing PWM control by varying a duty factor of a rectangular pulse. <P>COPYRIGHT: (C)2007,JPO&INPIT |
