Hao Jan (Max) Liu Dept. of Electrical & Computer Engineering University of Illinois, Urbana-Champaign ECE 498HZ: Power Distribution System Analysis OpenDSS Tutorial April 5, 2016

2 Acknowledgement  Most slides in this presentation have used and/or adapted content produced by Roger Dugan (EPRI, USA)  EPRI OpenDSS Files –

3 Outline  OpenDSS introduction  Key features –Built-in solution modes –Controls –Models implemented  User interfaces  Q&A

4 OpenDSS  Script-driven, frequency-domain distribution system simulation tool –Limited graphical user interface –Very flexible, e.g., COM interface with MATLAB  Power flow solver for unbalanced, multi-phase distribution networks –Both North American and European-style networks  Supports all rms steady-state analyses

Built-in Solution Modes  Snapshot (static) Power Flow  Daily mode (default: 24 1-hr increments)  Yearly mode (default hr increments)  Fault study  Harmonic  Custom user-defined solutions 5

Controls  A key feature is that controls are modelled separately from the devices being controlled –Capacitors –Regulators/tap changers  Control modes can be either static, time, or event based 6

Models Implemented  Line  Transformer  Capacitor  Generator  Load  PVsystem  Storage  EnergyMeter  Monitor  And more 7

User Interfaces  A stand-alone text-based executable program –Some graphical outputs –No graphical inputs  A COM server that supports driving the simulator from user written programs –MATLAB –Excel 8

Before You Start  Don’t forget the “sourcebus” –The slack/reference bus  OpenDSS mimics real-life networks –Monitors –Meters  Use the right frequency –Usually set at 60Hz 9

IEEE 13-Bus Network  “Clear” command  New circuit new circuit.IEEE13Nodeckt ~ basekv=115 pu= phases=3 bus1=SourceBus ~ Angle=30  Substation transformer New Transformer.Sub Phases=3 Windings=2 XHL=( /) ~ wdg=1 bus=SourceBus conn=delta kv=115 kva=5000 %r=( /) XHT=4 ~ wdg=2 bus=650 conn=wye kv=4.16 kva=5000 %r=( /) XLT=4 10

Regulator 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  Similarly, define regulators for other phases 11

Lines New linecode.mtx601 nphases=3 BaseFreq=60 ~ rmatrix = ( | | ) ~ xmatrix = ( | | ) ~ units=mi  Can be one, two, or three-phase lines New Line Phases=3 Bus1=RG Bus2= LineCode=mtx601 Length=2000 units=ft 12 RG RG mtx601

Loads New Load.671 Bus1= Phases=3 Conn=Delta Model=1 kV=4.16 kW=1155 kvar=660  Various load types 1. Normal load ‐ flow type load: constant P and Q 2. Constant impedance load 3. Constant P, Quadratic Q (somewhat like a motor) 4. Linear P, Quadratic Q (Mixed resistive, motor) 5. Rectifier load (Constant P, constant current) 6. Constant P; Q is fixed at nominal value 7. Constant P; Q is fixed impedance at nominal value 8. ZIP model 13

Create a Simple DSS File  Solve –Set Voltagebases –calcv –solve  Bus coordinate –An bus location coordinate can be defined to show relative bus location in the network  Save the.dss file 14

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Additional Resources  OpenDSS Download –  OpenDSS Wiki – ai n_Page  Roger Dugan's links for OpenDSS –  OpenDSS Presentations by EPRI (FTP)  OpenDSS Forum – 16