Active lifetime extension — Demonstrated for voltage source converters

Many voltage source converters have no redundant power components (e.g. IGBT modules) built in. Therefore if one power component fails, the converter stops working. Here we introduce a generic approach that takes advantage of the inherent redundancies of voltage vectors in multilevel converters in order to actively extend the lifetime of converters. When detecting increased stress of one IGBT module, the switching strategy is altered in order to reduce the load of that particular IGBT module. The active lifetime extension (ALE) switching strategy aims to balance the remaining life of all IGBT modules at all times. In such way the lifetime of the converter is maximized.