Quasi-dual modulation of three-phase PWM converters

This paper treats the possibility of transferring the modulation method developed for a pulse width modulated (PWM) converter with a dc voltage link (VLC) to a PWM converter with dc current link (CLC) based on the inverse current and voltage behavior of these two systems. The duality between VLC and CLC has been intuitively clear. This ″ duality ″ is treated here in a scientific approach. Especially, transferring of modulation methods from VLC to CLC and vice versa are beneficial for practical applications. The nonplanar property of three-phase bridge circuits leads to a quasidual relation of the switching states of the two systems. The code conversion of the binary switching functions of a VLC into control signals of the power electronic devices of a CLC is given. The remaining degree of freedom of the correspondence is set by the requirement of minimum switching frequency of the converter.