Circuit Breaker

Single-pole single-throw circuit breaker

Libraries:
Simscape / Electrical / Switches & Breakers

Description

The Circuit Breaker block models a single-phase circuit breaker that uses an external signal and phase current information to break an electrical circuit.

The table shows how the external signal vT and the Breaker Behavior parameter control the block behavior.

Condition		Block Behavior	Resistance Parameter Used
vT < Threshold		The breaker is closed. Port 1 connects to port 2.	Closed Resistance
vT ≥ Threshold	`Open when current crosses zero after vT >= Threshold`	When the current in port 1 goes through zero, the phase disconnects from port 2. The breaker is open.	Open Conductance
vT ≥ Threshold	`Open when vT >= Threshold`	The breaker is open.	Open Conductance

Examples

Frequency-Dependent Transmission Line

A custom frequency-dependent transmission line model. The characteristic admittance and propagation function are first derived from the frequency-dependent resistance, reactance, and susceptance. The derived values are fitted using RF Toolbox. The Universal Line Model (ULM) [1] is then implemented in Simscape based on the fitted parameters. The results from the frequency-dependent transmission line model and the classic pi-section transmission line model are compared.

Open Model

Ports

Refer to the figure for port locations.

Input

expand all

vT — Scalar control port
physical signal

Scalar physical signal control port.

Dependencies

To enable this port, set Modeling option to PS control port.

Conserving

expand all

1 — Port 1
electrical

Electrical conserving port.

2 — Port 2
electrical

Electrical conserving port.

+ — Positive port
electrical

Positive electrical conserving port.

Dependencies

To enable this port, set Modeling option to Electrical control port.

- — Negative port
electrical

Negative electrical conserving port.

Dependencies

To enable this port, set Modeling option to Electrical control port.

Parameters

expand all

Modeling option — Whether to specify physical or electrical control port
`PS control port` (default) | `Electrical control port`

Whether to specify physical or electrical control port for the switch gate.

Closed resistance — Closed resistance
`0.001` `Ohm` (default)

Resistance between ports 1 and 2 when the breaker is closed.

Open conductance — Open conductance
`1e-6` `1/Ohm` (default)

Conductance between ports 1 and 2 when the breaker is open.

Threshold — Threshold voltage
`0.5` `V` (default)

Threshold voltage for the control port vT. The block uses the threshold voltage and the value of vT at the start of the simulation to determine whether the breaker is initially open or closed. If you set Breaker Behavior to Open when current crosses zero after vT >= Threshold, when the voltage rises above the threshold, the breaker opens as its current crosses zero. If you set Breaker Behavior to Open when vT >= Threshold, the breaker opens as soon as the voltage rises above the threshold. When the control port voltage falls below the threshold, the breaker closes.

Breaker Behavior — Breaker Behavior when vT rises above threshold
`Open when current crosses zero after vT >= Threshold` (default) | `Open when vT >= Threshold`

Breaker Behavior when the value at the control port vT is greater than or equal to the value of the Threshold parameter. The breaker can open either as soon as the voltage rises above the threshold, or when its current also crosses zero.

Extended Capabilities

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

Version History

Introduced in R2013b

Circuit Breaker

Description