FAN CAPACITY REGULATOR FOR ALTERNATING-CURRENT LOCOMOTIVE Russian patent published in 2006 - IPC H02P27/04 H02M5/16 

FIELD: electrical engineering; ac consists.

SUBSTANCE: proposed device designed to regulate capacity of fans driven by three-phase induction motors has traction transformer 1 with its primary winding 2 connected to supply mains, auxiliary winding 4 with terminal and intermediate leads, frequency converter built around four thyristors, and control unit 9 whose outputs are connected to control inputs of thyristors. The latter are interconnected in two groups, each having two series-connected thyristors, and are connected to terminal leads of auxiliary winding. One thyristor group is connected to winding cumulatively and other group, differentially. Three-phase induction motor 10 is characterized in enhanced number of low-speed steps; its first phase lead is connected to common point of first-group thyristors, its second phase lead, to common point of second-group thyristors, and third phase lead, to intermediate lead of auxiliary winding.

EFFECT: enlarged range of fan capacity regulation by load current, reduced cost of locomotive auxiliary power.

1 cl, 1 dwg