CONTROLLING A THREE-PHASE ELECTRICAL CONVERTER

摘要

A method for controlling a three-phase electrical converter (12) comprises: selecting a three-phase optimized pulse pattern (20) from a table (22) of precomputed optimized pulse patterns based on a reference flux (ψαβ,ref); determining a two-component optimal flux {ψ*αβ ) from the optimized pulse pattern (20) and determine a one-component optimal third variable (ζ*); determining a two-component flux error from a difference of the optimal flux ( ψ*αβ ) and an estimated flux (ψαβ) estimated based on measurements in the electrical converter; determining a one-component third variable error from a difference of the optimal third variable (ζ*) and an estimated third variable (ζ); modifying the optimized pulse pattern (20) by time-shifting switching instants (28) of the optimized pulse pattern (20) such that a cost function depending on the time-shifts is minimized, wherein the cost function comprises a flux error term and a third variable error term, wherein the flux error term is based on a difference of the flux error and a flux correction function providing a flux correction based on the time-shifts and the third variable error term is based on a difference of the third variable error and a third variable correction function providing a third variable correction based on the time-shifts; and applying the modified optimized pulse pattern (26) to the electrical converter (12).