SRF2ABC:
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Transformation from abc to switching reference frame.
You need to pass the switching function matrix.
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Inputs
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SRF (3,1) Voltage or current in SRF reference frame
S (3,3) Switching function matrix
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Outputs
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ABC (3,1) Voltage or current in ABC reference frame
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Reference: Nikkhajoei et al "Dynamic Model of a Matrix Converter for
Controller Design and System Studies", IEEE Transactions
on Power Delivery, vol. 21, no. 2, April 2006, pp 744-754
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