Chopper design for NICTD locomotives

摘要

The design of a DC chopper requires a compromise among switching frequency, inductor size, and switching losses. There are three problems to be solved for the actual application of a DC chopper in electric railways. The first is the realization of a high-voltage chopper, the second is the reduction of inductive interference, and the third is the reduction of weight and cost of chopper equipment. The design principles of SCR choppers and GTO choppers are compared. Some of the simplified circuit diagrams for the proposed DC chopper design are discussed. The commerical availability of a 0-1500 V DC chopper that can be incorporated into an existing locomotive design is investigated and some of actual DC chopper controller circuits for the traction and locomotive systems produced by different vendors are discussed.