The Bias of the proportional Relation between the Value of Power-Frequency Characteristic Constant and the Block Capacity depending on Linkcd Position of the Block and its Effect

Abstract

The demand-supply imbalance on electric power system is absorbed by system frequency variations, before the LFC controls. Since frequency fluctuations are common in all linked blocks, demand-supply imbalance of one block is absorbed by another block too. Demand-supply imbalance arises in another block simultaneously, and is absorbed by the former block. These mutual supports have a direct effect on linkage power fluctuations. The size of this self-regulation is regarded as proportional to the size of frequency fluctuation and the ratio of the former to the latter is nearly proportional to the block capacity. But, at a short period variation range, there is a fear that such a proportional relation will be biased by linkage position. We analyze this point, and reached the following conclusions. First, we can prove the existence of self-regulation bias theoretically and point out that the bias has some effect on linkage power fluctuations at short period variation range. Second, we apply this analytical method to 4 blocks-linked system of Japan, and compare the theoretical value with measured one. The result indicates no correlation among demand fluctuations of those blocks which are presupposed for calculation of the theoretical values; among several blocks is found some ununiformity of the smallest unit size of demand power variations.