Orkney Active Network Management system Technical Session 1 Accessing capacity in a constrained network Active Network Management

Transcription

1 Orkney Active Network Management system Technical Session 1 Active Network Management David MacLeman Distribution R&D Manager 1

2 Learning Outcomes Understand the concept of ANM Identify and assess opportunities to apply ANM 2

3 What is Active Network Management? 3

4 Lesson content Introduction to Orkney The Orkney network problem definition Why Active Network Management? Design of an ANM scheme for Orkney Interactive session 1 What makes Orkney suitable for Active Network Management? Where else could you apply ANM? Review of sessions Lessons learnt 4

5 Introduction to the Orkney High interest in further renewable generator connections Traditional reinforcement solution would be very expensive Spare capacity available due to patterns of load and generation Ofgem incentives: IFI and DG Registered Power Zone (RPZ) 5

6 Orkney electrical network Wind farm with rating in MW 6 miles off north coast of Scotland 11,500 customers Min/Max demand: 6/31 MW 33 kv submarine cables: 2 x 20 MW import/export Existing generation a mix of wind, wave and gas Existing reactive compensation equipment Existing protection-based network management: Firm Generation (FG) Non-Firm Generation (NFG) Load shedding Single turbine with rating in MW Marine Energy with rating in MW Fossil Fuel generator with rating in MW STROMNESS Wave 7MW NORTH HOY Tidal 4MW 9.95MW BURGAR HILL 15.3 MW 2.55 MW Potential Constrained Cable 0.9MW LYNESS 0.9MW 4.5 MW Constrained line 2.7MW ROUSAY WESTRAY 0.9MW 0.9MW SCORRADALE ST MARYS FLOTTA 2.0 MW Gas 10.5MW Diesel 15MW 0.9MW KIRKWALL 0.85 MW Open point EDAY 0.9MW SHAPINSAY Constrained cable SANDAY 0.9MW 0.9MW STRONSAY 11kV circuit 33kV circuit 33kV interconnector to Scotland 33/11kV sub station Map by Martin Lee 1992 to

7 American Superconductor DVAR Initial Purpose - To provide continuous reactive power locally on Orkney in order to maximize the real power (MW) transfer capability of the sub sea cables from the mainland. -To provide voltage support for transient conditions such as those caused by trips and reactor switching. -Through maximizing the transfer capability, help minimize the need for running peak generation. The solution consists of a ±8 MVAR D-VAR and 2 X 7 MVAR, 33 kv switched shunt capacitors. The D-VAR solution in place protects the Orkney Islands power supply from critical contingency events such as the loss of one of the two 33 kilovolt (kv) underwater power cables that serve the islands. 7

8 Existing generator capacity on Orkney - Firm Generation DEMAND 6 MW FG 0-26 MW G Orkney FG = (N-1 circuit capacity) + (local minimum demand) 20 MW 20 MW FG = 20+6 = 26 MW Mainland 8

9 Post-fault inter-trip - Non Firm Generation DEMAND 6 MW NFG 0-20 MW FG 0-26 MW G G Orkney NFG = Capacity of both circuits + local minimum demand - FG Mainland 20 MW 20 MW NFG = = 20 MW Inter-trip NFG for N-1 contingency 9

10 Why Active Network Management? Local electrical network capacity has limits Existing planning rules require unconstrained output of contracted generation capacity at all times Variations in customer demand and output from renewable generators changes minute by minute Affects network capacity available to accommodate DG output

11 Active Network Management New Non Firm Generation NNFG 0-25 MW DEMAND 6-31 MW NFG 0-20 MW FG 0-26 MW G G G Orkney NNFG = Capacity of both circuits + local maximum demand - FG - NFG Mainland 20 MW 20 MW NNFG = = 25 MW NNFG enabled by new ANM scheme 11

12 Design of the ANM scheme ROUSAY Normally Open Point EDAY SANDAY Reactive compensation equipment solves almost all voltage problems Each zone has a thermal limitation on generation output at any given time Whole Orkney system has a further thermal limit on generation output Real time control of wind generation units based on measurements and control logic. Existing generation unaffected Operating margins are introduced to ensure network security Zone 1 BURGAR HILL STROMNESS WESTRAY STRONSAY SHAPINSAY SCORRADALE KIRKWALL NORTH HOY THURSO GRID LYNESS Orkney Core Zone 3 ST. MARY S FLOTTA Zone 2 Zone 4 12

13 Interactive session 2 What makes Orkney suitable for Active Network Management? 13

14 Interactive session 3 Where else can these principles be applied? 14

15 Review of interactive sessions What is Active Network Management (ANM)? What makes Orkney suitable? Where else can these principles be applied? 15

16 Review What is Active Network Management? The Orkney Registered Power Zone Where/when ANM can be a suitable solution The network is constrained (thermal, fault level, voltage) Where conventional reinforcements costs are high There is variation in demand There is diversity in the generation portfolio 16

17 Lesson 1 ends david.macleman@sse.com 17

18 Activity results What is Active Network Management? Some responses from small group discussion at Knowledge Sharing Event, 18 May 2012 Balancing generation and demand; Signal from the network in real time; Understanding capability/capacity of network; Lifetime of assets and constraints; Economic/ commercial balance Operational events based on network conditions or events; Dynamic line rating; Not passive; Network configuration/re-configuration; Resilience vs complexity 18

19 Activity results What is Active Network Management? Some responses from small group discussion at Knowledge Sharing Event, 18 May 2012 Real time management of constraint; Real time management in whatever form; Not protection - integration with protection; Risk against manual intervention; Avoiding hitting protection Near real time information; Understanding of operational boundaries; Optimisation; Increasing network utilisation; Facilitating carbon reduction; Facilitating cost effective network connection; Minimal impact on customer; Quality of supply 19