| 摘要 |
PURPOSE:To improve the accuracy of controllng a current by varying the hysteresis width of the set value in response to the magnitude of the output current of an inverter. CONSTITUTION:An inverter 2 is composed of switching elements 4-14 formed of GTOs, diodes 16-26 connected in a bridge. In order to control the inverter 2, a gate amplifier 40, a comparator 42, a hysteresis width altering circuit 44, a multiplier 46, an oscillator 48 and a current detector 50 are provided. When the output current is small, the hysteresis width of the comparator 52 is reduced by the altering circuit 44, while when the output current is large, the hysteresis width of the compartor 42 is increased. |
