| 摘要 |
PURPOSE:To enhance the reliability of an inverter to an overcurrent protection by discriminating the presence or absence of generating a DC shortcircuit from the output of an ON/OFF detector of a transistor to fire a thyristor. CONSTITUTION:When both transistor elements 1, 2 are together conducted to cause a DC shortcircuit, a malfunction discriminator 12 outputs a firing pulse G, thereby turning ON a thyristor 13. The shortcircuit current passes a shortcircuit having a fuse 8, the thyristor 13 and a fuse 9, and flows through the elements 1, 2. A large shortcircuit current flows to the fuses 8, 9, which are rapidly melted before the element 1 or 2 is thermally deteriorated. |
