| 摘要 |
A test arrangement for testing the function of a switching cell (7, 7') configured to be a component of a cascaded multi-level converter and having at least one energy storing capacitor (21 ) comprises a so-called back-to-back circuit having such said switching cells connected in series in two phase legs (23, 24) interconnected through a mid point (26, 27) of the respective phase leg. The number of switching cells in each phase leg of the arrangement is reduced with respect to the number of switching cells intended to be connected in series in a phase leg of a said cascaded multi-level converter for which the switching cells are designed. Each of the two phase legs of the arrangement has inductance means with an inductance of substantially the same magnitude as that of the inductance means in said phase leg of a said cascaded multi-level converter. At least one capacitor (25) is arranged in said interconnection. Means (13) are configured to control the semi- conductor devices of the switching cells for changing switching state thereof and means (28) are arranged for measuring the current through said phase legs of the arrangement upon such control. |
