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IGBT 3-Level Converter (3ph)

Purpose

3-phase 3-level neutral-point clamped IGBT converter

Library

Electrical / Converters

Description

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Implements a three-phase three-level IGBT converter with neutral point clamping. The gate input is a vector of three signals - one per leg. The topmost IGBT, connected to the positive dc level, is turned on if the corresponding gate signal is ≥ 1  , and the second IGBT if the signal is ≥ 0  . The third IGBT is turned on for signals ≤ 0   and the lowest one for signals ≤ - 1  . Gate signal values of 1  , 0   and - 1   connect the phase output to the positive, neutral and negative dc level. By applying a non-zero signal at the inhibit input marked with "x" you can turn off all IGBTs.

You can choose between two different converter models:


Note  Due to the switching conditions of the IGBT with Diode, this device cannot be turned off actively while the current is exactly zero. This may result in unexpected voltage waveforms if the converter is not loaded.

To resolve this problem, either use the IGBT 3-Level Converter with Parasitics, or allow a small non-zero load current to flow by connecting a large load resistance to the converter.


The electrical circuit for the converter is shown below:

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Parameters

For a description of the parameters see the documentation of the IGBT with Diode, the IGBT and the Diode.

Probe Signals

The three-level IGBT converters provide 36 probe signals grouped by leg. Each signal is a vector containing the appropriate quantities of the individual devices: voltage, current, conductivity, conduction loss and switching loss. The vector elements are ordered top-to-bottom.

For the IGBT 3-Level Converter with Parasitics the diode probe signal vectors are in the order: anti-parallel diodes (top-to-bottom), clamping diodes (top-to-bottom).