A linear State-Space Model for Distribution Grid

This repository contains the following material:

• Matlab code to obtain a linear model of distribution grid
• Matlab code to run time simulation of a distribution grid with the possibility to set up time resolution and duration
• Simulink model of an 11 bus network
• Matlab code to repeat the tests shown in paper [A state-space linear model for distribution grids]

You need an updated version of Matlab, possibly Matlab 2017 to run the Simulink model

Instructions to build a linear model of a distribution grid

• Run in Matlab the file BuildModel.m
• If needed modify the parameters of the grid, inverters and loads in the file Dynamic_Model
• Select the grid with Nnodes (e.g. Nnodes = 10 selects the grid used in the paper)

Instructions to run time simulation of a distribution grid

• Run in Matlab the file TimeSimulation.m
• If needed modify the parameters of the grid, inverters and loads in the file Dynamic_Model
• Select the grid with Nnodes (e.g. Nnodes = 10 selects the grid used in the paper)
• Select the time resolution of the simulation, by changing time_delta. I suggest at least 1e-4 and smaller for the best result, time_delta may degrade the solution depending on the grid.
• Select the number of point in time to be simulated with Nt.
• If needed modify the parameters uncertainty of inputs (slack voltage Eo, Irradiance G, PQ set points), this will create random phenomena of a certain amplitude that impact the status of the system..

Insutructions to repeat the tests shown in paper [A state-space linear model for distribution grids]

• It will be needed to run the matlab simulations, based on the linear model; then run the same simulations in Simulink and finally compare the results.

• Run in Matlab the file TestPaper.m

• The type of files and parameters used are simular to the one mentioned for the previous two sections of instructions.

• In this case the default parameter are the same as the one used in the paper, so the simulation will take quite a long time (hours).

• For quicker simulation reduce time_delta to 1e-4 or 1e-3 (but larger unaccuracy may appear).

• Run the file Initialization.m

• Open the simulink file named Test11bus.slx

• you will find three color blocks, where some simple manual modifications are to be applied in order to obtain the 3 testing conditions of the paper.

• Run the simulation (by default 5 seconds with 1e-5 seconds of time resolution)

• The structures Scope_Idq and Scope_Vdq will be saved in your workspace.

• type (depending on what scenario you tested in Simulink)

  • save 'ScopeOut_steady' Scope_Idq Scope_Vdq
  • save 'ScopeOut_PQrampchange' Scope_Idq Scope_Vdq
  • save 'ScopeOut_PQstepchange' Scope_Idq Scope_Vdq
  • save 'ScopeOut_Vstepchange' Scope_Idq Scope_Vdq

• When all the tree scenarios have been tested and the m files ScopeOut_PQramptest, ScopeOut_PQsteptest, ScopeOut_Vsteptest have been saved run PlotPaper.m

Copyright

2018, Institute for Automation of Complex Power Systems, EONERC

License

This project is released under the terms of the GPL version 3.

This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program.  If not, see <http://www.gnu.org/licenses/>.

For other licensing options please consult Prof. Antonello Monti.

Contact

• Andrea Angioni aangioni@eonerc.rwth-aachen.de
• Edoardo De Din ededin@eonerc.rwth-aachen.de

Institute for Automation of Complex Power Systems (ACS)
EON Energy Research Center (EONERC)
RWTH University Aachen, Germany