3-Phase Overmodulation
Purpose
Extend linear range of modulation index for 3-phase inverters
Library
Control / Modulators
Description
For three-phase signals, this block extends the linear range of the modulation index from \([-1, 1]\) to \([-1.154, 1.154]\) by adding a zero-sequence offset. This block may be used for the control of three-phase converters without neutral point connection such as the IGBT Converter (3ph).
Fig. 171 illustrates the working principle of the 3-Phase Overmodulation block in conjunction with the Symmetrical PWM.
Fig. 171 Working principle of the 3-Phase Overmodulation block