MONITORING OF THE AGING OF THE CAPACITORS IN A CONVERTER BY MEANS OF CAPACITANCE MEASUREMENT

摘要

In order to provide an apparatus (1) for converting an electrical current with at least one phase module (2a, 2b, 2c), which has an AC voltage terminal (31,31,31) and at least one DC voltage terminal (p, n), wherein a phase module branch (6p1, 6p2, 6p3, 6n1, 6n2, 6n3) is formed between each DC voltage terminal (p, n) and the AC voltage terminal (31,31,31), and wherein each phase module branch (6p1, 6p2, 6p3, 6n1, 6n2, 6n3) has a series circuit comprising submodules (7), which each have a capacitor (8) and at least one power semiconductor (T1, T2), by means of which apparatus (1) aging of the energy store can be established in a simple manner, the invention proposes capacitor diagnosis means for the time-dependent determination of the capacitance of each capacitor (8).