Full-Bridge Inverter

Purpose

Full-bridge voltage source inverter with filter inductance

Library

Electrical / Nanostep

Description

This component implements a full-bridge voltage source inverter including a filter inductor on the AC side. The component offers two configurations:

Sub-cycle average

The gate inputs are floating-point numbers with values between 0 and 1 representing the relative on-times of the controlled semiconductors over one simulation step. This technique is suited for real-time simulation on a CPU or a FlexArray solver.

Nanostep / Switched

The converter is simulated with time steps in the single-digit nanosecond range. The required Nanostep solver is available exclusively on the RT Box. In this configuration, the DC and AC sides are galvanically isolated. Any electrical connection between the two sides outside the component would therefore not reflect the real current and voltage situation and should be avoided. Both sides of the converter have current source behavior and must each be connected directly to a capacitor or a voltage source. The implementation has a weight of 1, which means it occupies 1/3 of a Nanostep solver.

For offline simulation, all power semiconductors in the converter are modeled with ideal switches. The individual switches are controlled with instantaneous logical gate signals. A switch is turned on when the corresponding gate signal is true.

Note

The Sub-cycle average and the Nanostep implementation cannot simulate a shoot-through or clamping of the DC side. Therefore, the gate signals for the upper and lower switch in each leg must never both become true at the same time. Also, the applied DC voltage must never become negative.

Parameters

Configuration

Allows you to chose between Sub-cycle average or Nanostep / Switched configuration.

Switch model (CPU code generation)

If the Configuration is set to Sub-cycle average, this parameter selects the switch model when CPU code is generated.

Semiconductor symbol

This setting lets you choose between IGBT and MOSFET for the symbol of the active semiconductor switches. It does not change the electrical behavior of the converter in simulation.

Inductance

A non-zero scalar specifying the filter inductance, in henries \((\mathrm{H})\).

Winding resistance

A scalar specifying the winding resistance, in ohms \((\Omega)\).

Assertions

When set to on, the block will flag an error if both gate signals in the same leg become true.

Nanostep Probe Signals

See Fig. 263 for the probe signal positions.

Fig. 263 Probes for the Full-Bridge Inverter

Inductor current

The current flowing out of the converter.

DC link current

The current flowing from the DC link into the converter.

Gate signals

A vector of the gate signals connected to the semiconductor switches.