The modulation strategies for a matrix structured direct ac to ac and ac to dcconverter is presented in this paper. In principle, for a given set of inputthree phase voltages, any desired set of output voltages can be synthesized by suitable toggling matrix switches. The unity IDF operation without input currents sensing is achieved only by the appropriate modulation strategies. The most general ac to ac conversion function has been modified for using in ac to dc converter. In the case of ac to dc conversion is also possible to prove that IDF correction does not required the current measurement but it is realized only by using appropriate modulation strategy. This modulation approach is based on the presumption that the input voltages in the three-phase grid system are sinusoidal. As are well known the grid supply voltages do not have such nice properties, there are the pollutions in higher voltage harmonics. So due to this at the third step the harmonic pollution should be considered in PWM algorithm. Further this paper presents aPWM algorithm for a three phase ac-dc converter, where the third and fifth harmonics are introduced in the input phase voltages. Mathematical analysis shows that the unity IDF can be reached also by appropriate evaluation of the duty-cycle functions. A PWM algorithm is proposed based on this developed theoretical achievement. All PWM algorithms were investigated theoretically and verified by simulations and experiment
B.04 Guest lecture
COBISS.SI-ID: 15478550Barcelona (20 hours - Programa de doctorat enenginyeria electronica UPC-UIB, Cursos i seminaris de formacio doctoral - CURS 2011-2012), 18-27 June, 2012. Barcelona, 2012. The pulse width modulation techniques for single and three-phase inverters are performed on UPC as doctoral course. The lectures were based on the analytical approach. Also the switching matrix theory was used for describing the modulation principle appropriate for grid connected converters with power factor correction.
B.05 Guest lecturer at an institute/university
COBISS.SI-ID: 16117014