Control strategy for an interleaved converter based on parallel H-bridge structures

Abstract

In order to supply the new inner triplet magnets of the High Luminosity Large Hadron Collider (HL-LHC) with the required 18kA of DC current, new power converters are under development. Given the demanding requirements on current, efficiency, dynamic response, precision and availability, the use of a modular converter structure based on parallel operation of N sub-converters with M parallel H-bridges inside is adopted, as this strategy allows to continue operation even under a fault scenario. In this structure, it is expected that each sub-converter will operate autonomously and that their output current will be a fraction of the magnet current. Then, in order to keep the system modularity, a regulation strategy for sub-converter control that only requires local variables, i.e. no need for the information of the remaining sub-converters, is proposed.