| 摘要 |
PURPOSE:To enable making a sampling synchronizer unnecessary by sampling the quantity of electricity of each terminal with a constant time period and by computing the quantity of electricity at an arbitrary time by the use of a specific calculation formula on the basis of said sampled value. CONSTITUTION:In a protective relay protecting a power equipment by sampling respective quantities of electricity at a plurality of terminals for detecting said quantities with a constant time period, there is provided a means for obtaining the quantity of electricity of each terminal at an arbitrary time by compotation. In this computing means for the quantity of electricity, the quantity of electricity X(t) at an arbitrary time t in an interval (0, Nh) is computed by a specific calculation formula on the basis of the digital value X(nh) at a point N obtained by sampling with a constant period h. In this manner, it is possipossible to omit a control circuit for synchronizing sampling. |
