It was developed in the 1970s by Strömberg, a predecessor to today’s global motor and drives industry leader, ABB.
The LV VSD addressed a long-standing limitation of the traditional squirrel-cage induction motor, which had remained fixed-speed since its invention by Nikola Tesla in 1888.
Prior to the introduction of VSDs, adjusting motor performance for variable loads typically relied on mechanical throttling methods, such as dampers or valves – solutions that did little in terms of energy efficiency.
Read the full article in DPA's November 2025 issue