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PWM generator with sawtooth carrier.
Extras/Modulators
2-level PWM generator with a sawtooth carrier. The input m is the modulation index with a linear range of [-1 1]. The switching function s outputs either 1 or -1. If the modulation index is a vector, the switching function is also a vector of the same width.
The block can be used to control the 2-Level IGBT Converter or the ideal 2-Level Converter. In these cases the modulation index must have a width of 3 to match the number of inverter legs.
The following figures illustrate different sampling methods offered by the modulator block. In the figure on the left, Natural Sampling is used. The right figure shows Regular Sampling, i.e. the modulation index is updated at the vertical flanks of the carrier. In both figures carrier signals with falling ramps are employed.