1HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Optimal Accommodation of DG
Dr Gareth Harrison
Dr Robin WallaceUniversity of Edinburgh, UK
2HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Overview
• Planning need
• Planning tool outline
• Example of operation
• Update and future work
• Adequacy/cost effectiveness of available tools
3HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Planning Need
• Voltage rise major issue in rural areas
• Mitigation techniques exist– Often expensive
• One alternative is to avoid or limit the need for mitigation in the first place– Indicate where capacity is available
• Must identify where capacity exists
4HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Planning Tool
• Transmission level studies – Distribution level more onerous
• Various methods applied (GAs, etc.)– DG placement for min loss/investment costs
• Aim here to maximise DG capacity – Optimal power flow
• Implemented with PSS/E and bespoke GUI
5HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
‘Reverse Load-ability’
• Standard PV generator models inadequate
• Steady state model of DG as negative load
• Use load shedding minimisation algorithm to add negative load– maximise power injections
• Termed ‘reverse load-ability’
6HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
180 kW DG on feeder
500 kW DG on feeder
Low demand profile
Simple 11 kV Feeder
7HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Update
• Original simplifications removed– fixed taps; lack of traditional generation
• Transformer voltage control issue– need to mimic voltage
• Applied to much larger system
• Consistent and logical results
8HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Extensive Network
9HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Future Work
• Project due to end in September 2003
• Other aspects– Economic analysis– Development of capacity expansion strategies
• Beyond September 2003– Adapt approach for fault level constraints
10HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Adequacy of Current Tools
• Not aware of commercial software tool– Academic tools address some aspects of need
• Recently developed tools address the need
• Assessment computationally intensive– Need for re-evaluation with new connections– Move to stochastic standards/planning?
11HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Cost Effectiveness
• Costs arise from– setup/integration, input/evaluation, computation
and inaccuracy
• Tool requirements– Easy to use, fast, accurate and can be integrated
effectively
• Some current tools likely to meet criteria
12HARRISON UK Author Session 4 – Block 4 – Question 9
Barcelona 12-15 May 2003
Other UoE papers at CIRED
• This work is part of a larger ongoing programme at the University of Edinburgh
• Papers presented at CIRED– 4.44 - Intelligent generator control– 4.62 - Domestic CHP – 4.63 - Optimal accommodation of DG