Next Level of Power Module Solution for PV C&I String Inverter with 1200 V H7 Technology in Easy3B Package

Inhalt:
Recently the new 1200 V TRENCHSTOP(TM) IGBT7 H7 and the 1200 V emitter-controlled 7 Rapid diode have been presented [1]. These are fast switching devices with low dynamic and conduction losses. To use the full capability of these technologies within a power module, an optimisation of the commutation loops regarding stray inductance for cos φ = -1 to 1 is necessary. A power module with a 3-level neutral-point clamped 2 (NPC2) topology within Easy3B package is developed with these latest chips for a 1000 VDC 150 kW PV string inverter in commercial and industrial (C&I) application. This paper shows how the module enables a low inductive commutation path with a proper PCB design for such high-power and current rating. Therefore, the normal operation as well as a target application failure mode are analysed. And it is described how the module is optimised for these modes. For both operation modes the stray inductance is reduced by 45% in comparison to a reference design, which is enabling the usage of such a high current module. Via an application simulation it is shown that the module efficiency increases by 0.15% in comparison to a common design. It shows also that the converter power output can increase from 125 kW up to 165 kW.