A Variable Speed Drive (VSD) is an electronic controller that adjusts the speed of a motor by varying the frequency and voltage supplied to it. In data centers it modulates pumps, fans, chiller compressors and cooling towers to match cooling output to load, cutting energy use substantially since power falls roughly with the cube of speed. It also softens motor starts.
Category: Cooling & Environmental Control · Subcategory: Heat Rejection · Part of the AIDC Technical Terminology reference.