# Library

ARTEMiS/SSN/Lines

# Blocks

# Description

These blocks implement the well-known Wideband line model, also known as the Universal Line Model in the literature [1].

These new blocks, known as SSN Wideband line model v2.0, implements an upgraded version of the Wideband line code that solves some rare numerical issues of the previous generation of SSN Wideband line models. There uses is also different in SSN models as they don’t require X-type NIB at their terminals.

The WideBand Line models implement an N-phases distributed parameters line model with frequency dependence of line parameters. In difference to the Marti-type FD line model which uses a constant modal transformation to compute the frequency dependent parameters, the WideBand model directly models all its frequency dependent parameter in the phase domain, avoiding the error caused by the use of a constant modal transformation matrix in FD line model. Cables in particular typically exhibit a strong frequency dependence of the modal transformation matrix, making the FD line model inaccurate in this case. The WideBand model is much more accurate with cables in this regard [1].

**RT-LAB task decoupling by mean of traveling wave delays**

The new SSN Wideband line model v2.0 also presents itself as two half-line blocks that transmit their traveling wave data by Simulink signals. The new Wideband line model can be used to decouple an electric systems, similarly of standard DPL models, but requires the users to manually route the two half-models in each SS_ subsystems of RT-LAB.

**Minimum delay requirements for multi-core decoupling**

The new Wideband line model requires that the fastest mode of the line has a transport delay of at least 2*Ts, where Ts is the model sampling time.

**Model symmetry:** the two half-line model, left and right, are actually identical and can be interchanged.

# Masks

# Parameters

**EMTP-RV Wideband line fitting file (.dat):** the name of the Wideband fitting data file, produced by EMTP-RV fitter or the eMEGAsim wideband fitter.

**Time step (s): **the model sample time in seconds.

# Input and Output signals

**Simulink connection points**

**Traveling wave signals**: the blocks have each one Simulink input and one Simulink output that must be connected to the complementary half-line, even across RT-LAB subsystems if RT-LAB model decoupling is desired.

**Physical Modeling connection points**

**Electric ports:** The line models also have PM type ports which corresponds to the electric phase connections in SPS.

# Examples

The models **ssn_WB2_2phaseRTLAB**, **ssn_WB2_4phase** and **ssn_WB2_6phase** are available on the path of ARTEMiS, in R2015A+ format.

# References

[1] A. Morched, B. Gustavsen and M. Tartibi, "A universal model for accurate calculation of electromagnetic transients on overhead lines and underground cables," IEEE Transactions on Power Delivery, vol. 14, no. 3, pp. 1032-1038, July 1999.

[2] C. Dufour, J. Mahseredjian , J. Bélanger, “A Combined State-Space Nodal Method for the Simulation of Power System Transients”, IEEE Transactions on Power Delivery, Vol. 26, no. 2, April 2011 (ISSN 0885-8977), pp. 928-935