Design of an input filter stage for a multi-phase H-bridge interleaved modular converter

The upgrade of the Large Hadron Collider (LHC) into High Luminosity-LHC (HL-LHC) presents different challenges, among them, the development of the power converters supplying the inner triplet magnets with the required 18 kA DC currents. In order to reach the current required and to accomplish the stringent requirements associated to this kind of applications, even under a fault scenario, redundancy and modularity are foreseen in the converter design. Consequently, the development of a 18 kA power converter built from N parallel-connected sub-converters having M modules inside is carried out. Within the sub-converter, the goal is to achieve a proper interconnection of the high-power modules in order to minimize the effect of parasitic interconnection inductances. This work presents the analysis of the DC-link input filter stage. The effect of the different parasitic elements associated to both the copper busbars for the power connections and the filtering elements is evaluated. In addition, the importance of physical arrangement of the modules concerning their firing sequence is investigated. The impact of the location of the capacitance and damping network - which are included to mitigate the effect of the parasitic inductances associated to the busbars - is analyzed and evaluated by simulations.