Operational group change manner and device and rhinoceros clo converter device null of rhinoceros clo

摘要

PURPOSE: To shorten the operation period for operation group switching by accurately predicting the zero point in an output current. ;CONSTITUTION: A forecast switching start point in time based on forecast phase difference α is determined by I*(α) zero point detecting portion 21, and the point in time when the measured value of output current become zero is determined by If zero point detecting portion 20. A transfer control processing unit 25 starts the reduction of output current at the forecast switching start point in time, stops the converter being operated when the output current becomes zero and starts the operation of other converters. At that time, the time difference TD between two points in time is determined by a zero point phase difference detection portion 23; forecast phase difference α is corrected so as to reduce said TD by a switching start timing processing unit 24; and this is reflected upon the subsequent transfer operation. Also, instead of reducing TD, pulsation of the quality of state for each portion of cycloconverter and load or time from the switching start point to the stop point of the converter in operation can be detected the forecast phase difference can be corrected in such a manner that they will be reduced.;COPYRIGHT: (C)1993,JPO&Japio