Programmable Electronic AC Loads: a Review on Hardware Topologies

Programmable electronic AC loads (PELs) are a new type of power electronic devices widely used by researches to emulate different load features, such as resistive, inductive, capacitive and non-linear loads. PELs are currently of great interest in the field of microgrid research, isolated or hybrid solar plants and power electronics device testing. This paper presents a review of PELs focusing on hardware topologies. Different hardware configurations are presented and discussed, explaining their functionality. One of the key issues regarding PELs design is the elimination of excessive active power drawn by the load. This can be performed by dissipating power in passive elements through DC-DC converters or re-injecting it into a receptive AC grid. Both options are explained and detailed in the paper.