Matrix converter switching strategy for abnormal voltage conditions using selective harmonic tracking algorithm

A dynamic space vector modulation (SVM) approach for matrix converter operation in unbalanced and non-sinusoidal input voltage condition is presented. The concept of varying the modulation index based on the output of the selective harmonic tracking algorithm with reference to the fictitious DC bus is introduced. The complex relationship between output voltage and input voltage vectors of matrix converter for unbalanced and non-sinusoidal conditions is avoided using selective harmonic tracking algorithm. Using the oscillating fictitious DC bus vector, a simplified SVM approach is proposed to operate the matrix converter under extreme input voltage conditions. This approach is based on simple compensation of the output voltage modulation vector with respect to the oscillating fictitious DC bus vector. The unbalanced and non-sinusoidal input voltages are automatically compensated so that the output voltage is balanced and sinusoidal with minimum compromise in the sinusoidal nature of input current. The validity of the selective harmonic tracking algorithm approach is verified through simulation.