Four-Quadrant Chopper

Controller-driven four quadrant DC-DC chopper

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Libraries:
Simscape / Electrical / Semiconductors & Converters / Converters

Description

The Four-Quadrant Chopper block represents a four-quadrant controlled chopper for converting a fixed DC input to a variable DC output. The block contains two bridge arms. Each bridge arm each has two switching devices.

You can choose from two fidelity levels for the converter model. The equivalent model option does not model the individual switching devices but returns equivalent results. If you need detailed results for the switching device dynamics, use the detailed model option. Otherwise, use the equivalent model for faster simulation. To simulate in real time, use the equivalent model. To validate the results, use the detailed model with a variable-step solver. To use the detailed model, set the Fidelity level parameter to Detailed model - switching devices. To use the equivalent model, set the Fidelity level parameter to Equivalent model - PWM-controlled.

If you choose the detailed model, each component is the same switching device, which you specify by setting the Switching device parameter. The switching devices that you can specify are implementations of blocks in the Simscape > Electrical > Semiconductors & Converters 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 antiparallel diode. The control signal port G accepts values in the interval [0,1]. When G is equal to 0 or 1, the averaged switch is fully opened or fully closed respectively. The switch behaves similarly to the Ideal Semiconductor Switch block with an antiparallel diode. When G is between 0 and 1, the averaged switch is partly opened. You can average the pulse-width modulation (PWM) signal over a specified period. You can then undersample the model and use modulation waveforms instead of PWM signals.

The figures show the equivalent circuit and the operation for the block.

To use the equivalent model as a rectifier, set all the elements of the PWM signal to zero. The model behaves as a diode rectifier.

Protection

The block contains an integral protection diode for each switching device. The 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.

To configure the internal protection diode block, use the Protection Diode parameters. This table shows how to set the Model dynamics parameter based on your goals.

Goals		Value to Select	Integral Protection Diode
Do not include protection.		None	None
Include protection.	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

Note

If you set the Switching device parameter to Averaged Switch, the block automatically models protection diodes with no dynamics and the Model dynamics parameter is not visible.

You can also include a snubber circuit for each switching device. Snubber circuits contain a series-connected resistor and capacitor. They 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 current change when a switching device turns on.

To include and configure a snubber circuit for each switching device, use the Snubbers parameters.

Modeling Thermal Effects

Since R2024b

You can expose the thermal port to model the effects of generated heat and device temperature. To expose the thermal port:

• In the Main settings, set the Fidelity level parameter to Detailed model - switching devices.

• In the Switching Devices settings, set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• In the Switching Devices settings, select the Model thermal effects parameter.

For more information on using thermal ports and on the Thermal Port parameters, see Simulating Thermal Effects in Semiconductors.

When you expose the thermal port, the Four-Quadrant Chopper block models the conduction losses and the turn-on and turn-off losses of the switching devices. The Four-Quadrant Chopper block uses the same methods to calculate these losses as these blocks with the On-state behavior and switching losses parameter set to Specify constant values:

• GTO

• IGBT (Ideal, Switching)

• MOSFET (Ideal, Switching)

• Thyristor (Piecewise Linear)

For more information about how the Four-Quadrant Chopper block calculates these losses, see the documentation for one of these blocks, depending on the option you select for the Switching device parameter.

If you enable the thermal port and you set the Integral protection diode parameter to Diode with no dynamics, the block also models reverse recovery loss for the protection diodes. The block uses the same method to calculate these losses as the Diode block with the Fidelity level parameter set to Ideal switching and the Diode model parameter to Piecewise linear.

With ideal switching, the block does not use a physics-based charge model. The block represents the losses that the charge creates during reverse recovery as an instantaneous loss.

The block applies reverse recovery losses by stepping up the junction temperature with a value equal to the reverse recovery loss divided by the total thermal mass at the junction.

If you set the Reverse recovery loss model parameter to Tabulated loss, the value of the Reverse recovery loss table, Erec(Tj, If) parameter specifies the dissipated energy as a function of the junction temperature and the forward current just before the switching event. The off-state voltage linearly scales the losses relative to the Turn-off voltage when measuring recovery loss, Vrec parameter value. The table uses delayed values for the current and voltage. To use a value in the lookup table that is close to the instantaneous value, set the Filter time constant for voltage and current values parameter to a value that is lower than the fastest switching period.

If you set the Reverse recovery loss model parameter to Fixed loss, the value of the Reverse recovery loss parameter specifies the energy dissipated during each turn-off event. If you select the Scale reverse recovery loss with current and voltage parameter, then the block scales this loss value linearly by the on-state current and the off-state voltage. To use scaling values that are close to the instantaneous values, set Filter time constant for voltage and current values to a value that is lower than the fastest switching period.

Gate Control

To connect Simulink^® gate-control voltage signals to the gate ports of the internal switching devices:

1. Convert each voltage signal using a Simulink-PS Converter block.

2. Multiplex the converted gate signals into a single vector using a Four-Pulse Gate Multiplexer block.

3. Connect the vector signal to the G port.

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, G_sat 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 G_sat 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]:

$$\begin{array}{l}{u}_I=\left(floor\left(u\cdot K\right)\right)\\ \widehat{u}=\frac{u_I}{K}\end{array}$$

Examples

DC Motor Control

A cascade speed-control structure for a DC motor. A PWM controlled four-quadrant Chopper is used to feed the DC motor. The Control subsystem includes the outer speed-control loop, the inner current-control loop, and the PWM generation. The total simulation time (t) is 4 seconds. At t = 1.5 seconds, the load torque increases. At t = 2.5 seconds, the reference speed is changed from 1000 rpm to 2000 rpm.

• Open Model

Four-Quadrant Chopper Control

Control a four-quadrant chopper. The Control subsystem implements a simple PI-based control algorithm for controlling the output current. The simulation uses both positive and negative references. The total simulation time (t) is 1 second. At t = 0.5 seconds, the polarity of the load DC source E is changed.

• Open Model

HESM Torque Control

Control the torque in a hybrid excitation synchronous machine (HESM) based electrical-traction drive. Permanent magnets and an excitation winding excite the HESM. A high-voltage battery feeds the SM through a controlled three-phase converter for the stator windings and through a controlled four quadrant chopper for the rotor winding. An ideal angular velocity source provides the load. The Control subsystem uses an open-loop approach to control the torque and a closed-loop approach to control the current. At each sample instant, the torque request is converted to relevant current references. The current control is PI-based. The simulation uses several torque steps in both the motor and generator modes. The Visualization subsystem contains scopes that allow you to see the simulation results.

• Open Model

HESM Velocity Control

Control the rotor angular velocity in a hybrid excitation synchronous machine (HESM) based electrical-traction drive. Permanent magnets and an excitation winding excite the HESM. A high-voltage battery feeds the HESM through a controlled three-phase converter for the stator windings and through a controlled four quadrant chopper for the rotor winding. An ideal torque source provides the load. The Control subsystem includes a multi-rate PI-based cascade control structure. The control structure has an outer angular-velocity-control loop and three inner current-control loops. The Visualization subsystem contains scopes that allow you to see the simulation results.

• Open Model

SM Torque Control

Control the torque in a synchronous machine (SM) based electrical-traction drive. A high-voltage battery feeds the SM through a controlled three-phase converter for the stator windings and a controlled four quadrant chopper for the rotor winding. An ideal angular velocity source provides the load. The Control subsystem uses an open-loop approach to control the torque and a closed-loop approach to control the current. At each sample instant, the torque request is converted to relevant current references. The current control is PI-based. The simulation uses several torque steps in both motor and generator modes. The task scheduling is implemented as a Stateflow® state machine. The Visualization subsystem contains scopes that allow you to see the simulation results.

• Open Model

SM Velocity Control

Control the rotor angular velocity in a synchronous machine (SM) based electrical-traction drive. A high-voltage battery feeds the SM through a controlled three-phase converter for the stator windings and a controlled four quadrant chopper for the rotor winding. An ideal torque source provides the load. The Control subsystem includes a multi-rate PI-based cascade control structure which has an outer angular-velocity-control loop and three inner current-control loops. The task scheduling in the Control subsystem is implemented as a Stateflow® state machine. The Visualization subsystem contains scopes that allow you to see the simulation results.

• Open Model

Single-Phase Inverter Current Control

Control the current in a single-phase inverter system. The single-phase inverter uses averaged switches fed by modulation waveforms. This example is suitable for real-time evaluation on a dedicated real-time emulator.

• Open Model

Power Converter Voltage Stabilizer

A voltage stabilizer circuit. It uses a full-wave rectifier, a single-wave inverter, and a buck-boost transformer to achieve voltage regulation.

• Open Model

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.

• If you use the block as a rectifier and you set the Fidelity level parameter to Equivalent model - PWM-controlled, the AC voltage must originate from an ideal active source, not a passive one like a mutual inductor.

Ports

Conserving

G — Switching device gate control

electrical | vector

Electrical conserving port associated with the gate terminals of the switching devices.

Data Types: double

1+ — Positive DC voltage 1

electrical | scalar

Electrical conserving port associated with the positive terminal of the first DC voltage.

Data Types: double

1- — Negative DC voltage 1

electrical | scalar

Electrical conserving port associated with the negative terminal of the first DC voltage.

Data Types: double

2+ — Positive DC voltage 2

electrical | scalar

Electrical conserving port associated with the positive terminal of the second DC voltage.

Data Types: double

2- — Negative DC voltage 2

electrical | scalar

Electrical conserving port associated with the negative terminal of the second DC voltage.

Data Types: double

H — Thermal port

thermal

Since R2024b

Thermal conserving port associated with the thermal mass of the switching devices.

Dependencies

To enable this port:

• In the Main settings, set the Fidelity level parameter to Detailed model - switching devices.

• In the Switching Devices settings, set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• In the Switching Devices settings, select the Model thermal effects parameter.

Parameters

Main

Fidelity level — Fidelity level

Detailed model - switching devices (default) | Equivalent model - PWM-controlled

Since R2024a

Level of fidelity of the model.

To prioritize simulation accuracy or to obtain results for the individual switching devices, set this parameter to Detailed model - switching devices.

To prioritize simulation speed, set this parameter to Equivalent model - PWM-controlled.

Switching Devices

To enable these parameters, set Fidelity level to Detailed model - switching devices.

This table shows how the visibility of Switching Devices parameters depends on the switching devices that you select. To learn how to read the table, see Parameter Dependencies.

Switching Devices Parameter Dependencies

Parameters and Options
Switching device
Ideal Semiconductor Switch	GTO	IGBT	MOSFET	Thyristor	Averaged Switch
On-state resistance	Model thermal effects	Model thermal effects	Model thermal effects	Model thermal effects	On-state resistance
	Gate trigger voltage, Vgt			Gate trigger voltage, Vgt
	Gate turn-off voltage, Vgt_off			Gate turn-off voltage, Vgt_off
	Holding current			Holding current
	Forward voltage	Forward voltage		Forward voltage
	On-state resistance	On-state resistance	Drain-source on resistance	On-state resistance
Off-state conductance	Off-state conductance	Off-state conductance	Off-state conductance	Off-state conductance	Integer for piecewise constant approximation of gate input (0 for disabled)
Threshold voltage		Threshold voltage	Threshold voltage

Switching device — Switch type

Ideal Semiconductor Switch (default) | GTO | IGBT | MOSFET | Thyristor | Averaged Switch

Switching device type for the converter.

Dependencies

See the Switching Devices Parameter Dependencies table.

Model thermal effects — Option to model thermal effects

Off (default) | On

Option to model thermal effects.

Dependencies

See the Switching Devices Parameter Dependencies table.

Gate trigger voltage, Vgt — Voltage threshold

1 V (default) | scalar

Gate-cathode voltage threshold. The device turns on when the gate-cathode voltage is above this value.

Dependencies

See the Switching Devices Parameter Dependencies table.

Gate turn-off voltage, Vgt_off — Voltage threshold

-1 V (default) | scalar

Gate-cathode voltage threshold. The device turns off when the gate-cathode voltage is below this value.

Dependencies

See the Switching Devices Parameter Dependencies table.

Holding current — Current threshold

1 A (default) | scalar

Gate current threshold. The device stays on when the current is above this value, even when the gate-cathode voltage falls below the gate trigger voltage.

Dependencies

See the Switching Devices Parameter Dependencies table.

Forward voltage — Voltage

0.8 Ohm (default) | scalar

For the different switching device types, the Forward voltage is taken as:

• GTO — Minimum voltage required across the anode and cathode block ports for the gradient of the device I-V characteristic to be 1/R_on, where R_on is the value of On-state resistance

• IGBT — Minimum voltage required across the collector and emitter block ports for the gradient of the diode I-V characteristic to be 1/R_on, where R_on is the value of On-state resistance

• Thyristor — Minimum voltage required for the device to turn on

Dependencies

See the Switching Devices Parameter Dependencies table.

On-state resistance — Resistance

0.001 Ohm (default) | scalar

For the different switching device types, the On-state resistance is taken as:

• GTO — Rate of change of voltage versus current above the forward voltage

• Ideal semiconductor switch — Anode-cathode resistance when the device is on

• IGBT — Collector-emitter resistance when the device is on

• Thyristor — Anode-cathode resistance when the device is on

• Averaged switch — Anode-cathode resistance when the device is on

Dependencies

See the Switching Devices Parameter Dependencies table.

Drain-source on resistance — Resistance

0.001 Ohm (default) | scalar

Resistance between the drain and the source, which also depends on the gate-to-source voltage.

Dependencies

See the Switching Devices Parameter Dependencies table.

Off-state conductance — Conductance

1e-5 1/Ohm (default) | scalar

Conductance when the device is off. The value must be less than 1/R, where R is the value of On-state resistance.

For the different switching device types, the On-state resistance is taken as:

• GTO — Anode-cathode conductance

• Ideal semiconductor switch — Anode-cathode conductance

• IGBT — Collector-emitter conductance

• MOSFET — Drain-source conductance

• Thyristor — Anode-cathode conductance

Dependencies

See the Switching Devices Parameter Dependencies table.

Threshold voltage — Voltage threshold

6 V (default) | scalar

Gate voltage threshold. The device turns on when the gate voltage is above this value. For the different switching device types, the device voltage of interest is:

• Ideal semiconductor switch — Gate-cathode voltage

• IGBT — Gate-emitter voltage

• MOSFET — Gate-source voltage

Dependencies

See the Switching Devices Parameter Dependencies table.

Integer for piecewise constant approximation of gate input (0 for disabled) — Integer mode for FPGA deployment

0 (default) | nonnegative scalar

Integer used to perform piecewise constant approximation of the gate input for FPGA deployment.

Dependencies

To enable this parameter, set Switching device to Averaged Switch.

Switching Losses

To enable these parameters:

• In the Main settings, set the Fidelity level parameter to Detailed model - switching devices.

• In the Switching Devices settings, set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• In the Switching Devices settings, select the Model thermal effects parameter.

This table shows how the visibility of Switching Loss parameters depends on the Switching device parameter in the Switching Devices settings. To learn how to read the table, see Parameter Dependencies.

Switching Losses Parameter Dependencies

Parameters and Options
Switching device
GTO	IGBT	MOSFET	Thyristor
Switch-on loss	Switch-on loss	Switch-on loss	Switch-on loss
Switch-off loss	Switch-off loss	Switch-off loss
Natural commutation rectification loss			Natural commutation rectification loss
Off-state voltage for switching loss data	Off-state voltage for switching loss data	Off-state voltage for switching loss data	Off-state voltage for switching loss data
On-state current for switching loss data	On-state current for switching loss data	On-state current for switching loss data	On-state current for switching loss data
Wait time before switch-on current measurement			Wait time before switch-on current measurement
Use last on-state current from previous cycle for turn-on loss	Use last on-state current from previous cycle for turn-on loss	Use last on-state current from previous cycle for turn-on loss
Use last off-state voltage from previous cycle for turn-on loss	Use last on-state current from previous cycle for turn-on loss	Use last on-state current from previous cycle for turn-on loss

Switch-on loss — Switch-on loss

22.86e-3 J (default) | positive scalar

Since R2024b

Energy dissipated during a single switch-on event.

Dependencies

To enable this parameter, set Switching Device to GTO, IGBT, MOSFET, or Thyristor.

Switch-off loss — Switch-off loss

17.14e-3 J (default) | positive scalar

Since R2024b

Energy dissipated during a single switch-off event.

Dependencies

To enable this parameter, set Switching Device to GTO, IGBT, or MOSFET.

Natural commutation rectification loss — Natural commutation rectification loss

10e-3 J (default) | positive scalar

Since R2024b

Rectification loss applied at the point that the block switches off when the current falls below the Holding current parameter value. Specify this parameter using a scalar quantity.

Dependencies

To enable this parameter, set Switching Device to GTO or Thyristor.

Off-state voltage for switching loss data — Off-state voltage for losses data

300 V (default) | positive scalar

Since R2024b

The output voltage of the device during the off state. This is the blocking voltage at which the switch-on loss and switch-off loss data are defined.

Dependencies

To enable this parameter, set Switching Device to GTO, IGBT, MOSFET, or Thyristor.

On-state current for switching loss data — Output current

600 A (default) | positive scalar

Since R2024b

Output currents for which the switch-on loss, switch-off loss, and on-state voltage are defined. The first element must be zero. Specify this parameter using a scalar quantity.

Note

This parameter is measured at the point that the gate voltage falls below the Gate trigger voltage, Vgt. The turn-on pulse is longer than the time it takes the current to reach its maximum value.

Dependencies

To enable this parameter, set Switching Device to GTO, IGBT, MOSFET, or Thyristor.

Wait time before switch-on current measurement — Wait time before switch-on current measurement

0 s (default) | nonnegative scalar

Since R2024b

Time to wait before recording the on-state current.

Dependencies

To enable this parameter, set Switching Device to GTO or Thyristor.

Use last on-state current from previous cycle for turn-on loss — Option to use last on-state current from previous cycle for turn-on loss

Off (default) | On

Since R2024b

Option to use the last on-state current from previous cycle for turn-on loss.

Dependencies

To enable this parameter, set Switching Device to GTO, IGBT, or MOSFET.

Use last off-state current from previous cycle for turn-offloss — Option to use last off-state current from previous cycle for turn-off loss

Off (default) | On

Since R2024b

Option to use the last off-state current from previous cycle for turn-off loss.

Dependencies

To enable this parameter, set Switching Device to GTO, IGBT, or MOSFET.

Protection Diode

To enable these parameters, set Fidelity level to Detailed model - switching devices.

The visibility of Diode parameters also depends on how you configure the protection diode Model dynamics and Reverse recovery time parameterization parameters. To learn how to read this table, see Parameter Dependencies.

Protection Diode Parameter Dependencies

Parameters and Options
Model dynamics
None	Diode with no dynamics	Diode with charge dynamics
	Forward voltage	Forward voltage
	On resistance	On resistance
	Off conductance	Off conductance
		Junction capacitance
		Peak reverse current, iRM
		Initial forward current when measuring iRM
		Rate of change of current when measuring iRM
		Reverse recovery time parameterization
		Specify stretch factor	Specify reverse recovery time directly	Specify reverse recovery charge
		Reverse recovery time stretch factor	Reverse recovery time, trr	Reverse recovery charge, Qrr

Note

If you set the Switching device parameter to Averaged Switch, the block automatically models protection diodes with no dynamics and the Model dynamics parameter is not visible.

Model dynamics — Diode model

None (default) | Diode with no dynamics | Diode with charge dynamics

Diode type. The options are:

• None.

• Diode with no dynamics — Select this option to prioritize simulation speed using the Diode block.

• Diode with charge dynamics — Select this option to prioritize model fidelity in terms of reverse mode charge dynamics using the commutation model of the Diode block.

Dependencies

See the Protection Diode Parameter Dependencies table.

Forward voltage — Voltage

0.8 V (default) | scalar

Minimum voltage required across the positive and negative block ports for the gradient of the diode I-V characteristic to be 1/R_on, where R_on is the value of On resistance.

Dependencies

See the Protection Diode Parameter Dependencies table.

On resistance — Resistance

0.001 Ohm (default) | scalar

Rate of change of voltage versus current above the Forward voltage.

Dependencies

See the Protection Diode Parameter Dependencies table.

Off conductance — Conductance

1e-5 1/Ohm (default) | scalar

Conductance of the reverse-biased diode.

Dependencies

See the Protection Diode Parameter Dependencies table.

Reverse recovery loss model — Model for reverse recovery loss

Fixed loss (default) | Tabulated loss

Since R2024b

Whether to model fixed or tabulated reverse recovery losses.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

Reverse recovery loss — Reverse recovery loss

0 J (default) | nonnegative scalar

Since R2024b

Dissipated energy in each turn-off event, regardless of the state of the diode before or after the switching event.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Set Reverse recovery loss model to Fixed loss.

Scale reverse recovery loss with current and voltage — Option to scale reverse recovery loss

On (default) | Off

Since R2024b

Option to scale reverse recovery loss with current and voltage.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Set Reverse recovery loss model to Fixed loss.

Forward current when measuring recovery loss, Irec — Forward current when the block measures recovery loss

10 A (default) | positive scalar

Since R2024b

Forward current through the diode before the reverse recovery event that the block uses to measure recovery loss.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Set Reverse recovery loss model to Fixed loss.

• Select the Scale reverse recovery loss with current and voltage parameter.

Turn-off voltage when measuring recovery loss, Vrec — Turn-off voltage when measuring recovery loss

10 V (default) | positive scalar

Since R2024b

Voltage across the diode after the reverse recovery event used to measure recovery loss.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Choose from one of these options:

  • Set Reverse recovery loss model to Fixed loss and select the Scale reverse recovery loss with current and voltage parameter.

  • Set the Reverse recovery loss model parameter to Tabulated loss.

Filter time constant for voltage and current values — Filter time constant for voltage and current values

1 / 1000 / 100 s (default) | positive scalar

Since R2024b

Filter time constant for voltage and current values used to calculate reverse recovery loss. Set this parameter to a value that is lower than the fastest switching period.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Choose from one of these options:

  • Set Reverse recovery loss model to Fixed loss and select the Scale reverse recovery loss with current and voltage parameter.

  • Set the Reverse recovery loss model parameter to Tabulated loss.

Reverse recovery loss table, Erec(Tj, If) — Reverse recovery loss

zeros(2, 3) J (default) | vector of nonnegative scalars

Since R2024b

Dissipated energy as a function of the forward current If just before the switching event, and final off-state voltage once the diode is in off state.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Set the Reverse recovery loss model parameter to Tabulated loss.

Temperature vector for recovery loss table, Tj — Temperature vector for recovery loss table

[298.15, 398.15] K (default) | vector

Since R2024b

Temperature vector used to tabulate reverse recovery loss.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Set the Reverse recovery loss model parameter to Tabulated loss.

Forward current vector for recovery loss table, If — Forward current vector for recovery loss table

[.1, 1, 10] A (default) | vector of nonnegative scalars

Since R2024b

Forward current vector used to tabulate reverse recovery loss.

Dependencies

To enable this parameter:

• Set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• Select the Model thermal effects parameter parameter.

• Set Integral protection diode to Diode with no dynamics.

• Set the Reverse recovery loss model parameter to Tabulated loss.

Junction capacitance — Capacitance

50 nF (default) | scalar

Diode junction capacitance.

Dependencies

See the Protection Diode Parameter Dependencies table.

Peak reverse current, iRM — Current

-235 A (default) | negative scalar

Peak reverse current measured by an external test circuit.

Dependencies

See the Protection Diode Parameter Dependencies table.

Initial forward current when measuring iRM — Current

300 A (default) | positive scalar

Initial forward current when measuring peak reverse current. This value must be greater than zero.

Dependencies

See the Protection Diode Parameter Dependencies table.

Rate of change of current when measuring iRM — Current change rate

-50 A/us (default) | scalar

Rate of change of current when measuring peak reverse current.

Dependencies

See the Protection Diode Parameter Dependencies table.

Reverse recovery time parameterization — Recovery-time model

Specify stretch factor (default) | Specify reverse recovery time directly | Specify reverse recovery charge

Model for parameterizing the recovery time. When you select Specify stretch factor or Specify reverse recovery charge, you can specify a value that the block uses to derive the reverse recovery time. For more information on these options, see How the Block Calculates TM and Tau.

Dependencies

See the Protection Diode Parameter Dependencies table.

Reverse recovery time stretch factor — Stretch factor

3 (default) | scalar greater than 1

Value that the block uses to calculate Reverse recovery time, trr. Specifying the stretch factor is an easier way to parameterize the reverse recovery time than specifying the reverse recovery charge. The larger the value of the stretch factor, the longer it takes for the reverse recovery current to dissipate.

Dependencies

See the Protection Diode Parameter Dependencies table.

Reverse recovery time, trr — Time

15 us (default) | scalar

Interval between the time when the current initially goes to zero (when the diode turns off) and the time when the current falls to less than 10 percent of the peak reverse current.

The value of the Reverse recovery time, trr parameter must be greater than the value of the Peak reverse current, iRM parameter divided by the value of the Rate of change of current when measuring iRM parameter.

Dependencies

See the Protection Diode Parameter Dependencies table.

Reverse recovery charge, Qrr — Charge

1500 s*uA (default) | scalar

Value that the block uses to calculate Reverse recovery time, trr. Use this parameter if the data sheet for your diode device specifies a value for the reverse recovery charge instead of a value for the reverse recovery time.

The reverse recovery charge is the total charge that continues to dissipate when the diode turns off. The value must be less than $$-\frac{i^2{}_{RM}}{2a}$$,

where:

• i_RM is the value specified for Peak reverse current, iRM.

• a is the value specified for Rate of change of current when measuring iRM.

Dependencies

See the Protection Diode Parameter Dependencies table.

Snubbers

To enable these parameters, set Fidelity level to Detailed model - switching devices and Switching device to one of these options:

• Ideal Semiconductor Switch

• GTO

• IGBT

• MOSFET

• Thyristor

Snubber — Snubber model

None (default) | RC snubber

Switching device snubber.

Snubber resistance — Resistance

0.1 Ohm (default) | scalar

Resistance of the switching device snubber.

Dependencies

To enable this parameter, set Snubber to RC Snubber.

Snubber capacitance — Capacitance

1e-7 (default) | F | scalar

Capacitance of the switching device snubber.

Dependencies

To enable this parameter, set Snubber to RC Snubber.

Thermal Port

To enable these parameters:

• In the Main settings, set the Fidelity level parameter to Detailed model - switching devices.

• In the Switching Devices settings, set the Switching device parameter to one of these options:

  • GTO

  • IGBT

  • MOSFET

  • Thyristor

• In the Switching Devices settings, select the Model thermal effects parameter.

Thermal network — Options for thermal network modeling

External (default) | Specify junction and case thermal parameters | Cauer model | Cauer model parameterized with Foster coefficients

Since R2024b

Options for modeling the thermal network of the block.

Thermal mass parameterization — Option to parameterize thermal mass

By thermal time constants (default) | By thermal mass

Since R2024b

Options to parameterize the thermal mass:

• By thermal time constants — Parameterize the thermal masses in terms of thermal time constants.

• By thermal mass — Specify the thermal mass values directly.

Dependencies

To enable this parameter, set Thermal network to Specify junction and case thermal parameters, Cauer model, or Cauer model parameterized with Foster coefficients.

Junction case and case-ambient (or case-heatsink) thermal resistances, [R_JC R_CA] — Junction case and case-ambient (or case-heatsink) thermal resistances

[.08, .5] K/W (default) | vector of positive values

Since R2024b

Row vector [ R_JC R_CA ] of two thermal resistance values, represented by two Conductive Heat Transfer blocks. The first value, R_JC, is the thermal resistance between the junction and the case. The second value, R_CA, is the thermal resistance between port H and the device case.

Dependencies

To enable this parameter, set Thermal network to Specify junction and case thermal parameters.

Junction and case thermal time constants, [t_J t_C] — Junction and case thermal time constants

[.001, .2] s (default) | vector of positive values

Since R2024b

Row vector [ t_J t_C ] of two thermal time constant values. The first value, t_J, is the junction time constant. The second value, t_C, is the case time constant.

Dependencies

To enable this parameter, set Thermal network to Specify junction and case thermal parameters and Thermal mass parameterization to By thermal time constants.

Junction and case thermal masses, [M_J M_C] — Junction and case thermal masses

[.01, .5] J/K (default) | vector of positive values

Since R2024b

Row vector [ M_J M_C ] of two thermal mass values. The first value, M_J, is the junction thermal mass. The second value, M_C, is the case thermal mass.

Dependencies

To enable this parameter, set Thermal network to Specify junction and case thermal parameters and Thermal mass parameterization to By thermal mass.

Junction and case initial temperatures, [T_J T_C] — Junction and case initial temperatures

[25, 25] degC (default) | vector of positive values

Since R2024b

Row vector [ T_J T_C ] of two temperature values. The first value, T_J, is the junction initial temperature. The second value, T_C, is the case initial temperature.

Dependencies

To enable this parameter, set Thermal network to Specify junction and case thermal parameters.

Thermal resistances, [R1 R2 … Rn] — Thermal resistances

[.08,.1,.5] K/W (default) | [.08,.14,.22,.16] K/W | vector of positive values

Since R2024b

Row vector of n thermal resistance values, represented by the Cauer elements used in the thermal network.

If you set Thermal network to Cauer model, the default value is [.08,.1,.5]. If you set Thermal network to Cauer model parameterized with Foster coefficients, the default value is [.08,.14,.22,.16].

Dependencies

To enable this parameter, set Thermal network to Cauer model or Cauer model parameterized with Foster coefficients.

Thermal masses, [M1 M2 … Mn] — Thermal masses

[.01,.1,.5] J/K (default) | [.001,.005,.05,.5] J/K | vector of positive values

Since R2024b

Row vector of n thermal mass values, where n is the number of Cauer elements used in the thermal network.

If you set Thermal network to Cauer model, the default value is [.01,.1,.5]. If you set Thermal network to Cauer model parameterized with Foster coefficients, the default value is [.001,.005,.05,.5].

Dependencies

To enable this parameter, set Thermal network to Cauer model or Cauer model parameterized with Foster coefficients and Thermal mass parameterization to By thermal mass.

Thermal masses initial temperatures, [T1 T2 … Tn] — Thermal masses initial temperatures

[25, 25, 25] degC (default) | vector of positive values

Since R2024b

Row vector of temperature values that corresponds to the temperature drop across each thermal capacity in the model.

Dependencies

To enable this parameter, set Thermal network to Cauer model.

Thermal time constants, [t1 t2 … tn] — Thermal time constants

[.001,.1,.2] s (default) | [7e-05, .0007, .01, .08] s | vector of positive values

Since R2024b

Row vector of n thermal time constant values, where n is the number of Cauer elements used in the thermal network. The length of this vector must match the length of Thermal resistances, [R1 R2 … Rn]. With this parameterization, the thermal masses are computed as Mi = ti/Ri, where Mi, ti and Ri are the thermal mass, thermal time, and thermal resistance for the i^th Cauer element (if you set Thermal network to Cauer model) or Foster element (if you set Thermal network to Cauer model parameterized with Foster coefficients).

If you set Thermal network to Cauer model, the default value is [.001,.1,.2]. If you set Thermal network to Cauer model parameterized with Foster coefficients, the default value is [7e-05, .0007, .01, .08].

Dependencies

To enable this parameter, set Thermal network to Cauer model or Cauer model parameterized with Foster coefficientsand Thermal mass parameterization to By thermal time constants.

Initial node temperatures, [T1 T2 ... Tn] — Initial node temperatures

[25, 25, 25, 25] degC (default) | vector of positive values

Since R2024b

Row vector of absolute temperature values of each node starting from the junction.

Dependencies

To enable this parameter, set Thermal network to Cauer model parameterized with Foster coefficients.

Junction thermal mass — Thermal mass of junction

0.01 J/K (default) | positive scalar

Since R2024b

Thermal mass of the junction.

Dependencies

To enable this parameter, set Thermal network to External.

For more information about using thermal ports and the Thermal Port parameters, see Simulating Thermal Effects in Semiconductors.

References

[1] Trzynadlowski, A. M. Introduction to Modern Power Electronics, 2nd Edition. Hoboken, NJ: John Wiley & Sons Inc., 2010.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2018a

R2024b: Model thermal effects by exposing the thermal port

You can now expose the thermal port to model the effects of generated heat and device temperature. When you expose the thermal port, the Four-Quadrant Chopper block models the conduction losses and the turn-on and turn-off losses of the switching devices. If you enable the thermal port and you set the Integral protection diode parameter to Diode with no dynamics, the block also models reverse recovery loss of the protection diodes.

R2024a: Increase simulation speed using an equivalent model

You can now choose from two fidelity levels for the converter model. The equivalent model option does not model the individual switching devices but returns equivalent results. If you need detailed results for the switching device dynamics, use the detailed model option. Otherwise, use the equivalent model for faster simulation. To simulate in real time, use the equivalent model. To validate the results, use the detailed model with a variable-step solver.

To use the detailed model, set the Fidelity level parameter to Detailed model - switching devices. To use the equivalent model, set the Fidelity level parameter to Equivalent model - PWM-controlled.

Before R2024a, you can use the detailed model only.