| 摘要 |
PURPOSE:To prevent the turbulence of an output current wave-form in case of the interruption of load currents by controlling a firing angle so that a voltage area in which the instantaneous value of an inverter main circuit increases more than load electromotive force is proportioned to current command value. CONSTITUTION:A switch 60 is connected to a point A during the time when the load currents i1 before the point of time t50 continues, the controller firing angle alpha1 is inputted to a controller 10, and a cycloconverter main circuit 4 is controlled. When the load currents start interruption at the point of the time t51, a switching signal s1 is changed into a logic ''1'' while a latch signal s2 is generated. When electromotive voltage eCU is detected simultaneously, arithmetical operation is conducted successively, and the corrected firing angle alphaIC is obtained, and outputted toward the controller 10 as alpha1'. Accordingly, the voltage area AP1 of output voltage e1 is proportioned to the current command value i1 at the point of time t52 as shown in an oblique line at the point of time t52. |
