Abstract
Recently, regenerative brakes are implemented in trains at DC fed electric railways in Japan. Regenerative braking system converts kinetic energy to electrical energy. And other powering trains at the identical feeding circuit must consume the electrical energy. Therefore, when the electrical loads are not sufficient at feeding circuit, braking trains must squeeze regenerative power. The problem is that such braking trains often squeeze regenerative power excessively, that results in low energy efficiency of the regenerative system in average. Authors have tried to calculate the maximal regenerative action in an ideal case, in which the full usage of the regenerative brake in guaranteed by and ideal data communication system named PDIS (Power Distribution Instruction System). And, authors furthermore realistic squeezing controls of regenerative brakes in future based on the results in the ideal case.
