1. Distribution Load Flow using OpenDSS (An Open Source Software of EPRI)

2. Contents of presentation
Definition of Loads
Definition of Lines
Definition of Capacitors
Definition of Transformer/Voltage Regulator
Writing Master File
COM Interfacing with MATLAB
Writing MATLAB Program for Load-flow
(Examples for Loads, Lines, Capacitors, Transformer/VR are defined for IEEE-13 Node Test System)
Data can be obtained from

3. Definition of Loads Required Platform are .DSS or .txt or .m
Remember style is same as in .DSS
New Load.671 Bus1= Phases=3 Conn=Delta Model=1 kV= ~kW=1155 kvar=660
For .m
DSSText.Command=‘New Load.671 Bus1= Phases=3 Conn=Delta Model=1 kV= kW=1155 kvar=660 ’;
Available Load Models in OpenDSS
Model
Description 1
Constant P and Q 2
Constant impedance load 3
Constant P, Quadratic Q 4
Linear P, Quadratic Q 5
Rectifier load 6
Constant P; Q is fixed at nominal value 7
Constant P; Q is fixed impedance at nominal value 8
ZIP model

4. Definition of Lines Writing Line Code
New linecode.mtx601 nphases=3 BaseFreq=60
~ rmatrix = ( | | )
~ xmatrix = ( | | )
~ units=mi
Create Line (Can be one, two, or three-phase lines)
New Line Phases=3 Bus1=RG ~Bus2= LineCode=mtx601 Length=2000 ~units=ft

5. Capacitor Definition
New Capacitor.Cap1 Bus1=675 phases=3 kVAR=600 kV=4.16
New Capacitor.Cap2 Bus1=611.3 phases=1 kVAR=100 kV=2.4

6. Definition of Transformer/ Voltage Regulator
Transformer Definition
New Transformer.Sub Phases=3 Windings=2 XHL=( /) wdg=1 bus=SourceBus conn=delta kv=115 kva= %r=( /) XHT=4 wdg=2 bus=650 conn=wye kv=4.16 kva= %r=( /) XLT=4
Regulator Definition
New Transformer.Reg1 phases=1 XHL=0.01 kVAs=[ ] Buses=[650.1 RG60.1] kVs=[ ] %LoadLoss=0.01
new regcontrol.Reg1 transformer=Reg1 winding=2 vreg=122 band=2 ptratio=20 ctprim=700 R=3 X=9
New Transformer.Reg2 phases=1 XHL=0.01 kVAs=[ ] Buses=[650.2 RG60.2] kVs=[ ] %LoadLoss=0.01
new regcontrol.Reg2 transformer=Reg2 winding=2 vreg=122 band=2 ptratio=20 ctprim=700 R=3 X=9
New Transformer.Reg3 phases=1 XHL=0.01 kVAs=[ ] Buses=[650.3 RG60.3] kVs=[ ] %LoadLoss=0.01
new regcontrol.Reg3 transformer=Reg3 winding=2 vreg=122 band=2 ptratio=20 ctprim=700 R=3 X=9

7. Defining Master File new circuit.MasterIEEE13
~ basekv=115 pu=1.0 phases=3 bus1=SourceBus
~ Angle=30 MVAsc3=20000 MVASC1=21000
Redirect Transformers
Redirect Lines
Redirect Loads
Redirect Capacitors
Set Voltagebases=[115, 4.16, .48]
Calcv
Solve

8. COM Intefacing DSSObj = actxserver('OpenDSSEngine.DSS')
DSSText=DSSObj.Text

9. Writing MATLAB File clear all; clc;
DSSObj = actxserver('OpenDSSEngine.DSS');
if ~DSSObj.Start(0),
disp('Unable to start the OpenDSS Engine');
return
end
DSSText = DSSObj.Text;
DSSCircuit = DSSObj.ActiveCircuit;
DSSText.Command='Compile (C:\Users\Admin\Desktop\SaturdayExample\MasterIEEE13.dss)';
DSSText.Command='batchedit load..* Vmin=0.8';
DSSText.Command='solve mode=snap';
DSSText.Command='Solve';
DSSText.Command='Export Losses';
DSSText.Command='Export Voltages';
DSSText.Command='Export Currents';

10. Losses Report

11. Voltage Report