Development of Scientific-and-Experimental Stand to Study Operating Processes of New Transistor Converter of Alternating Current Locomotive

The article deals with various aspects of experimental stand construction for studying the operating processes of thyristor and transistor reversible converters of alternating current locomotive in the traction mode. Two types of reversible converter main circuit execution are provided at the stand – on the basis of thyristors and on the basis of transistors with specified technical features. The elements of electrical and mechanical equipment are listed in each circuit of converter, functions of these elements are explained. The article considers examples of thyristor and transistor converters operation in the mode of rectifier (the mode of locomotive traction) at the upper bands of regulation (the second band, the third one) where the rectifier operation differs from the first band. The oscillograms of converters operating processes are represented as current and voltage curves in the primary winding of transformer and in the circuit of rectified current of load (traction motor). Their comparison is given as well. Based on the results of comparative tests of thyristor and transistor converters operation in the rectifier mode at the upper bands of regulation, an experimental dependence of the electric locomotive power factor on changes in band voltage has been obtained. The comparative assessment of energy efficiency of converters operation has been provided by means of its power factor measurement for half-value (0.5) and total value (1.0) of regulation band voltage.