4. Conclusion

In voltage converters, modulation consists in generating the opening and closing sequence of power switches, in order to ensure an exchange of electrical energy. The modulation scheme is based on a comparison between two signals, the modulating signal and the carrier signal. The modulating signal can be likened to the duty cycle applied to the two complementary switches that make up the elementary switching cell. The carrier signal is generally a "triangle" signal whose frequency defines the switching frequency, which must be high in relation to the operating frequency linked to the load's characteristic time constant. In this article, the basic scheme for implementing pulse-width modulation is detailed before being applied to various chopper and inverter conversion structures. After introducing frequency analysis tools, the usual performance criteria, both temporal and frequency, are defined...