| 摘要 |
PURPOSE:To enable the stable minimum control lead angle (betamin) of a main rectifier to be variably controlled by detecting the commutation overlapping- angle of a motor field rectifier, and by estimating the communication overlapping-angle or commutation constant of the main rectifier through the commutation over-lapping-angle of the motor field rectifier, to set the betamin. CONSTITUTION:By a commutation overlapping-angle detector 81, a natural commutation overlapping-angle uo' in case of the field current value IF of a field rectifier 45 is detected, and through this detected value, the commutation overlapping-angle uo of the field rectifier 45 in the case of the field current IF corresponding to armature current IAF=IA is estimated. First, a commutation constant K is found, and after that, the commutation overlapping-angle uo in the case of IF=IA is found. Then, arithmetic is performed on the betamin of each main rectifier according to the commutation overlapping-angle uo, by a betamin setting device 82, and its value is set as a set value and is applied to each main rectifier. As a result, the stable betamin at a high speed can be variably controlled. |
