Converter (Three-Phase)
Controller-driven bidirectional AC/DC three-arm converter
Libraries:
Simscape /
Electrical /
Semiconductors & Converters /
Converters
Description
The Converter (Three-Phase) block models a three-arm converter circuit that connects a three-phase AC network to a DC network.
Each component in the three-arm circuit is the same switching device, which you specify using an option on the Converter (Three-Phase) block dialog box. The switching devices that you can specify are implementations of blocks in the Simscape > Electrical > Semiconductors & Converters > Semiconductors library:
GTO — Gate turn-off thyristor. For information about the I-V characteristic of the device, see GTO.
Ideal semiconductor switch — For information about the I-V characteristic of the device, see Ideal Semiconductor Switch.
IGBT — Insulated-gate bipolar transistor. For information about the I-V characteristic of the device, see IGBT (Ideal, Switching).
MOSFET — N-channel metal-oxide-semiconductor field-effect transistor. For information about the I-V characteristic of the device, see MOSFET (Ideal, Switching).
Thyristor — For information about the I-V characteristic of the device, see Thyristor (Piecewise Linear).
Averaged Switch — Semiconductor switch with an anti-parallel diode. The control signal port, G, accepts values in the
[0,1]
interval. When the value at port G is equal to0
or1
, the averaged switch is either fully opened or fully closed, and it behaves similarly to the Ideal Semiconductor Switch block with an anti-parallel diode. When the value at port G is between0
and1
, the averaged switch is partly opened. You can then average the PWM signal over a specified period. This allows for undersampling of the model or using modulation waveforms instead of PWM signals.
The figure shows the equivalent circuit for a converter with fully controlled switching devices (e.g. IGBTs, GTOs).
The figure shows the equivalent circuit for a converter with partially controlled switching devices (e.g. thyristors).
Control the gate ports of the six switching devices via an input to port G on the Converter (Three-Phase) block:
Multiplex all six gate signals into a single vector with a Six-Pulse Gate Multiplexer block.
Connect the output of the Six-Pulse Gate Multiplexer block to the Converter (Three-Phase) block G port.
You can specify an integral protection diode for each switching device. An integral diode protects the semiconductor device by providing a conduction path for reverse current. An inductive load can produce a high reverse-voltage spike when the semiconductor device suddenly switches off the voltage supply to the load.
The table shows you how to set the Integral protection diode parameter based on your goals.
Goals | Value to Select | Integral Protection Diode |
---|---|---|
Prioritize simulation speed. | Diode with no dynamics | The Diode block |
Prioritize model fidelity by precisely specifying reverse-mode charge dynamics. | Diode with charge dynamics | The dynamic model of the Diode block |
You can include a snubber circuit, consisting of a resistor and capacitor connected in series, for each switching device. Snubber circuits protect switching devices against high voltages that inductive loads produce when the device turns off the voltage supply to the load. Snubber circuits also prevent excessive rates of change of current when a switching device turns on.
Piecewise Constant Approximation in Averaged Switch for FPGA Deployment
If you set the Switching device parameter to Averaged switch
and your model uses a partitioning solver, this block produces nonlinear partitions because the average mode equations include modes, Gsat that are functions of the input G. To make these equations compatible with hardware description language (HDL) code generation, and therefore FPGA deployment, set the Integer for piecewise constant approximation of gate input (0 for disabled) parameter to a value greater than 0
. This block then treats the Gsat mode as a piecewise constant integer with a fixed range. This turns the previously nonlinear partitions to linear time varying partitions.
An integer value in the range [0,K]
, where K is the value of the Integer for piecewise constant approximation of gate input (0 for disabled), is now associated with each real value mode in the range [0,1]
. The block computes the piecewise constant mode by dividing the original mode by K to normalize it back to the range [0,1]
:
Examples
Assumptions and Limitations
If, in the Solver Configuration block inside your model, you set the Solver type parameter to Partitioning, the averaged switches introduce instability during dead time, when all gate inputs are set to 0. Where possible, use the open-zero state by setting all high-side switches to 0 and all low-side switches to 1.
Ports
Conserving
Parameters
Extended Capabilities
Version History
Introduced in R2013bSee Also
Average-Value DC-DC Converter | Bidirectional DC-DC Converter | Buck Converter | Buck-Boost Converter | Boost Converter | GTO | IGBT (Ideal, Switching) | MOSFET (Ideal, Switching) | Ideal Semiconductor Switch | PWM Generator | PWM Generator (Three-phase, Two-level) | Six-Pulse Gate Multiplexer | Three-Level Converter (Three-Phase) | Thyristor (Piecewise Linear)