| 摘要 |
<p>The invention relates to a method and a controller (8) for protection of a voltage source converter (1) comprising one or more phases (L1, L2, L3), each phase comprising one or more series- connected converter cells (2-1L1, 2-2L1,..., 2-nL1; 3-1L2, 3-2L2,..., 3-nL2 : 4-1L3, 4-2L3,..., 4-nL3). Each converter cell comprises a by-pass switch (S-1L1, S-2L1,..., S-nL1; S-1L2, S-2L2,..., S-nL2; S-1L3, S-2L3,..., S-nL3) for enabling by-pass thereof. The method comprises the steps of: detecting an over-voltage condition, and controlling simultaneously the by-pass switches of each converter cell so as to bypass the converter cells upon detection of such over- voltage condition.</p> |
