Specific requirements

• RT-LAB

• MATLAB SIMULINK

Circuit Design Using the Simscape Electrical Specialized Power Systems (SPS) Libraries

The circuit must be designed using a special subset of blocks found in the SPS libraries. Also, these blocks must be properly named such that they can be easily managed outside the eHS solver.

Supported Block

In the SPS Elements library, the following blocks are supported (refer to the figure below):

• Series RLC Branch/Load

• Parallel RLC Branch/Load

• Ground/Neutral

• Breaker

• Pi Section Lines

• Linear Transformers

• Mutual Inductances

• Inductance Matrix Type Transformers

• Saturable Transformers (only supported in some specific firmware)

Open

Elements supported in the SPS Elements library

In the SPS Measurements block library, the following blocks are supported (refer to the figure below):

• Current Measurement

• Voltage Measurement

• Three-Phase VI Measurement

Open

Elements supported in the SPS Measurements block library

In the SPS Power Electronics block library, the following blocks are supported (refer to the figure below):

• Breaker

• Diode

• IGBT

• IGBT/Diode

• Ideal Switch

• Three-Level Bridge

• Thyristor

• Universal Bridge

In the SPS Electrical Sources block library, the following elements are supported (refer to the figure below):

• DC Voltage Source

• AC Voltage Source

• AC Current Source

• Controlled Voltage Source

• Controlled Current Source

• Three-Phase Source

Component Naming 

The algorithm implemented by OPAL-RT (to convert the SPS model into the data used by the eHS to compute the currents and voltages in the circuit in real time) requires that the model be analyzed to find the supported elements listed above. For source and switch control signals, as well as measurement outputs, the corresponding elements are listed in alphabetical order and will be accessible in that order within the Simulink/RT-LAB environments. For that reason, it is strongly recommended to rename elements with names that are easily recognizable and whose identification from within RT-LAB will be straightforward. The following naming convention is strongly recommended:

• Switching devices should be named with the prefix “SW” followed by a 2-digit index, starting from SW01. Elements categorized as “switching elements” are the following: Diode, IGBT/Diode, Breaker and Ideal Switch. This prefix can be followed by other

• Sources, whether controlled current or voltage sources, should have the prefix “U” followed by a 2-digit index, starting from U01. This prefix can be followed by others. To avoid confusion, the prefix for a three-phase source should contain three indices, starting with phase A (e.g. “U05 U06 U07 Vabc”).

• Measurements of any kind should have the prefix “Y” followed by a 2-digit index, starting from This prefix can be followed by other characters.

• Inductances, capacitors and resistors are not accessed directly from RT-LAB and do not have any special naming.

An example of a valid SPS model for a three-phase inverter is shown on the figure below.