Abstract

This work deals with a simple algorithm to define the dc current reference of a CSI-UPQC aimed to reduce its losses. The proposal uses the mathematical model of the CSI-UPQC to demonstrate the relationship between the dc current level and the modulation amplitude of the series stage. With this concept, a straightforward algorithm is proposed to set the dc current level to keep the modulation index of the series stage in a preset range, allowing to reduce of the dc current level compared with the use of a fixed dc current level and, therefore, reducing the losses in the power valves and dc inductor. The mathematical analysis illustrates the proposal, and simulated results corroborate it. © The Author(s), under exclusive license to Springer Nature Switzerland AG 2025.