| 摘要 |
<p>An electrical converter (10) has a balancing property such that a capacitor voltage of a capacitor (16) of the electrical converter tends towards a balancing voltage. A method for controlling the electrical converter (10) comprises: generating switching signals for the electrical converter (10) based on pulse width modulation, wherein switching instants (36) are determined by comparing a reference voltage signal (38) with a carrier signal (40); determining a state of unbalance of at least one capacitor (16) of the electrical converter, the state of unbalance (vd) being based on a difference between an actual capacitor voltage and a desired reference voltage; determining, whether the state of unbalance (vd) is outside a natural balancing region (44); and, in the case, the state of unbalance (vd) is outside the natural balancing region (44), phase shifting of a regular carrier signal (40), such that the capacitor voltage of the capacitor tends more directly in the direction of the natural balancing region (44) than during pulse width modulation with the regular carrier signal (40), whereby a phase shift (48) for the phase shifting of the regular carrier signal (40) is determined by minimizing a cost function based on the state of unbalance (vd) and/or a DC link voltage ofthe electrical converter (10).</p> |
