Rectifier (Three-Phase)

Uncontrolled three-phase AC to DC voltage

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Libraries:
Simscape / Electrical / Semiconductors & Converters / Converters

Description

The Rectifier (Three-Phase) block models a three-arm diode bridge circuit that converts a three-phase AC voltage to a DC voltage. The figure shows the equivalent circuit for the three-arm diode bridge.

Using the Charge Dynamics tab of the block dialog box, you can choose the type of diode that the three-arm bridge circuit uses. The table shows you how to set the Model dynamics parameter based on your goals.

Goal	Value to Select	Block Behavior
Prioritize simulation speed.	No dynamics	Each arm of the bridge circuit uses a copy of the Diode block. The block dialog box does not display additional parameters.
Precisely specify reverse-mode charge dynamics.	Model charge dynamics	Each arm of the bridge circuit uses a copy of the commutation model of the Diode block. The block dialog box shows parameters relating to the commutation model of the block.

Examples

Composite Three-Phase Rectifier

This is the base model for analysis workflow examples.

• Open Model

Model 18-Pulse Diode Rectifier

Model an 18-pulse diode rectifier to reduce the line current harmonics.

• Since R2024b
• Open Model

Model 24-Pulse Diode Rectifier

Model a 24-pulse diode rectifier to reduce the line current harmonics.

• Since R2024b
• Open Model

Ports

Conserving

~ — Three-phase port

electrical

Expandable three-phase port.

Dependencies

To enable this port, set Electrical connection to Composite three-phase ports.

a — a-phase

electrical

Electrical conserving port associated with a-phase.

Dependencies

To enable this port, set Electrical connection to Expanded three-phase ports.

b — b-phase

electrical

Electrical conserving port associated with b-phase.

Dependencies

To enable this port, set Electrical connection to Expanded three-phase ports.

c — c-phase

electrical

Electrical conserving port associated with c-phase.

Dependencies

To enable this port, set Electrical connection to Expanded three-phase ports.

+ — Positive terminal

electrical

Electrical conserving port associated with the positive terminal.

- — Negative terminal

electrical

Electrical conserving port associated with the negative terminal.

Parameters

Main

Electrical connection — Electrical connection

Composite three-phase ports (default) | Expanded three-phase ports

Whether to have composite or expanded three-phase ports.

Forward voltage — Forward voltage

0.8 V (default)

Minimum voltage required across the + and - ports of each diode for the gradient of the diode i-v characteristic to be 1/R_on, where R_onis the value of On resistance.

On resistance — On resistance

0.001 Ohm (default)

Rate of change of voltage versus current above the forward voltage for each diode.

Off conductance — Off conductance

1e-5 1/Ohm (default)

Conductance of each reverse-biased diode.

Charge Dynamics

Model dynamics — Diode charge dynamics

No dynamics (default) | Model charge dynamics

Diode charge dynamics. The default value is No dynamics.

The charge dynamics options you can select are:

• No dynamics

• Model charge dynamics

Junction capacitance — Junction capacitance

50e-9 F (default)

Diode junction capacitance.

Dependencies

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics.

Peak reverse current, iRM — Peak reverse current

-235 A (default) | negative scalar

Peak reverse current measured by an external test circuit. This value must be less than zero.

Dependencies

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics.

Initial forward current when measuring iRM — Initial forward current when measuring iRM

300 A (default) | positive scalar

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

Dependencies

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics.

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

-50A/μs (default) | negative scalar

Rate of change of current when measuring peak reverse current. This value must be less than zero.

Dependencies

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics.

Reverse recovery time parameterization — Reverse recovery time parameterization

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

Determines how you specify reverse recovery time in the block. The default value is Specify reverse recovery time directly.

If you select Specify stretch factor or Specify reverse recovery charge, you 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

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics.

Reverse recovery time, trr — Reverse recovery time

15 μs (default)

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% 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

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics and the Reverse recovery time parameterization parameter is set to Specify reverse recovery time directly.

Reverse recovery time stretch factor — Reverse recovery time stretch factor

3 (default)

Value that the block uses to calculate Reverse recovery time, trr. This value must be greater than 1. 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

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics and the Reverse recovery time parameterization parameter is set to Specify stretch factor.

Reverse recovery charge, Qrr — Reverse recovery charge

1500 μAs (default)

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

This parameter is visible only when the Model dynamics parameter is set to Model charge dynamics and the Reverse recovery time parameterization parameter is set to Specify reverse recovery charge.

For more information on these parameters, see Diode.

Extended Capabilities

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

Version History

Introduced in R2013b

R2021b: Electrical connection ports update

From R2021b forward, to switch between composite and expanded ports, set the Electrical connection parameter to either Composite three-phase ports or Expanded three-phase ports.

As a result of these changes, inside a model saved in an earlier release, review the Electrical connection parameter of this block.