SPMT Switch

Single-pole multiple-throw switch

Since R2020a

• 

Libraries:
Simscape / Electrical / Switches & Breakers

Description

The SPMT Switch block models a single-pole multiple-throw switch. You can specify three to eight throw connections by setting the Number of throw ports parameter to the desired amount. If you only need one or two throw ports, see the SPST Switch and SPDT Switch blocks.

The switch control port physical signal, vT, specifies which throw port connects to the pole:

• When vT is in the [-inf, 1.5] range, the pole always connects to throw port 1, n1.

• When vT is between one and the number of throw ports, the signal value is rounded to the nearest integer. The pole then connects to the throw port that corresponds to the integer value.

• When vT is higher than the number of throw ports, the pole always connects to the last throw port.

Open connections are modeled by a resistor with a value equal to the reciprocal of the Open conductance parameter value. Closed connections are modeled by a resistor with a value equal to the Closed resistance parameter value.

Assumptions and Limitations

• The values of the open conductance and closed resistance are the same for all throw ports.

• Switch dynamics and custom thresholds are not modeled.

Ports

Refer to the figure for port locations.

Input

vT — Switch control port

physical signal

Signal that opens and closes the switch, specified as a physical signal.

Conserving

p — Common port

electrical

Electrical conserving port associated with the common pole.

n1 — Throw port 1

electrical

Electrical conserving port associated with the first throw.

n2 — Throw port 2

electrical

Electrical conserving port associated with the second throw.

n3 — Throw port 3

electrical

Electrical conserving port associated with the third throw.

n4 — Throw port 4

electrical

Electrical conserving port associated with the fourth throw.

Dependencies

To enable this port, set Number of throw ports to 4, 5, 6, 7, or 8.

n5 — Throw port 5

electrical

Electrical conserving port associated with the fifth throw.

Dependencies

To enable this port, set Number of throw ports to 5, 6, 7, or 8.

n6 — Throw port 6

electrical

Electrical conserving port associated with the sixth throw.

Dependencies

To enable this port, set Number of throw ports to 6, 7, or 8.

n7 — Throw port 7

electrical

Electrical conserving port associated with the seventh throw.

Dependencies

To enable this port, set Number of throw ports to 7 or 8.

n8 — Throw port 8

electrical

Electrical conserving port associated with the eighth throw.

Dependencies

To enable this port, set Number of throw ports to 8.

Parameters

Main

Number of throw ports — Number of throw ports

4 (default) | 3 | 5 | 6 | 7 | 8

Number of throw connections.

Closed resistance — Closed resistance

0.01 Ohm (default) | positive scalar

Resistance between the p port and the throw ports when the switch is closed. The value must be greater than zero.

Open conductance — Open conductance

1e-6 S (default) | positive scalar

Conductance between the p port and the throw ports when the switch is open. The value must be greater than zero.

Faults

Enable throw port position stuck fault — Whether to enable throw port stuck fault

Off (default) | On

Whether throw port stuck faults can occur when the specified conditions are met.

Reporting when a fault occurs — Type of fault reporting

None (default) | Warn | Error

Type of reporting when a fault occurs:

• None — Does not generate a warning or an error.

• Warn — Generates a warning.

• Error — The simulation stops and generates an error.

Dependencies

To enable this parameter, set Enable throw port position stuck fault to On.

Fault trigger — Type of fault trigger

Temporal (default) | Behavioral

Type of fault trigger.

Dependencies

To enable this parameter, set Enable throw port position stuck fault to On.

Simulation time for fault event — Simulation time for fault event

1 s (default) | positive scalar

Amount of time before a temporal fault is triggered.

Dependencies

To enable this parameter, set:

• Enable throw port position stuck fault to On.

• Fault trigger to Temporal.

Maximum permissible common port current — Maximum permissible common port current

inf A (default) | positive scalar

Maximum current that is permitted to flow through the common port, above which a fault may be triggered.

Dependencies

To enable this parameter, set:

• Enable throw port position stuck fault to On.

• Fault trigger to Behavioral.

Time to fail when exceeding current — Time to fail when exceeding current

1 s (default) | positive scalar

Amount of time that the common port current must continuously exceed the maximum permissible current before a behavioral fault is triggered.

Dependencies

To enable this parameter, set:

• Enable throw port position stuck fault to On.

• Fault trigger to Behavioral.

Extended Capabilities

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

Version History

Introduced in R2020a