Agile uninterruptible power supply for efficient critical load support and grid contingency ride-through

Abstract

The present disclosure provides a method for maintaining continuous power to a critical load. The method comprises providing a source side converter (SSC) configured to provide autonomous grid support including reactive power support during fault conditions and a load side converter (LSC) configured to support the critical load by boosting voltage at load terminals through autonomous injection of reactive current, each coupled to a DC energy storage. The method includes coupling the SSC to an AC source and coupling the LSC to the critical load. The AC source and the critical load are connected via a bypass connection including a ride-through inductor with measurement capability. Under nominal source conditions, the SSC and the LSC are controlled so that a majority of power consumed by the critical load flows through the bypass connection. The method involves monitoring electrical parameters of the bypass connection and compensating for critical load variations using either the SSC or LSC or both based on bypass connection measurements.