CASE STUDY: COOKHOUSE 140MW WIND PLANT INTEGRATION

Transcription

1 Insert image here CASE STUDY: COOKHOUSE 140MW WIND PLANT INTEGRATION Compiled by D. Hadebe (Tx Planning) Acknowledgement: R. Palackal (System Operator) T. Gcabashe (Dx Planning)

2 Contents Project background & Regional long-term plan Developer s design layout Network Layout and Results (Before WEF) Studies Performed and Results (After WEF) Technical solution & Summary

3 Aggeneis Project Background Aries Kronos 8 applications received for REBID 1 = 700MW ). Sizing: phase 1 is 132kV (N-0) 140MW (2.1MW to 3MW turbines, 315kVA Perseus construction and 500kVA auxiliary Future phases up to 400MW or 600MW (on 220kV or 400kV Beta Milestones: Advanced EIA (RoD issued in May 2010 for up to 200 turbines). Key Planned connection date: REBID 1 IPP & network connection timeline (2 nd half of 2013) 400kV substation Van der Kloof Hydro-Electric station Helios Hydra Gariep Pumped storage scheme Gas turbine station Juno Nuclear station Droerivier 400kV line Aurora Poseidon 765kV line Koeberg Acacia Muldersvlei Bacchus Proteus Grassridge Line from a power station Philippi Palmiet Acacia 180MW other IPPs

4 Regional Long-Term Plan

5 Developer s Design Layout SVC: C=200Sw, 50Fx, L=200

6 Network Layout and Results: Before Firm upstream network

7 Studies Performed 5 scenarios using DFIG and Fully Rated gen models: Base: HL, no RE gen (ToSP) HL, HG LL, HG test effect of Q compensation in area HL, LG not critical (part of TDP) LL,LG not critical (part of TDP) Monitored thermal loadings, voltage levels for system healthy and relevant N-1 contingencies, fault levels before and after gen integration. LL and HL with gen rejection (v-rise test) Studies based on grid code compliant gen model (DFIG) Default planning methodology is unity power factor, if it fails to check voltage control. Excluded: Dynamic studies and QoS studies.

8 Results: After (high load) POC PCC

9 Results: Fault Currents (max only) Before After S/gear kv/ka 1-ph 3-ph 1-ph 3-ph Min. Posdn Posdn Psdn Cookh Cookh ph contribution Psdn1: Cookh1=1.4kA 3-ph contribution Psdn1: Cookh1=2.6kA C-factor = 1.1, Gen Xsource=X_subtrans=0.2 (0.33 for Fully Rated) Trfr taps ratios and phase shift angles unchanged FACTS devices blocked

10 Technical Solution & Summary Equipping of either spare 132kV feeder 2 or 3 at Poseidon Tx scope is 100% shallow, no deep scope of work Project status: Budget quote in progress, 1 st site meeting held in Feb 2012 (to identify type of protection, telecommunication requirements, metering specifications, Self-build option for 132kV line or not, capital costs, Tx timeframe of months from acceptance of budget quote, etc.) Proposed 140MW generator meets the tested planning criteria based on unity power factor control. Note: Developer stated that a type 2 generator plus STATCOM will be installed to ensure compliance with the SAGC requirements (eg. LVRT).

11 THANK YOU

12 Results: After (DFIG, high load)

13 Zoomed in at Cookhouse PCC POC

14 Results: DFIG with Psdn2_1 N-1

15 Results: DFIG with Psdn4_2 N-1

16 Results: DFIG rejection < 1% V change at Poseidon busbars, Cookhouse 132kV and 33kV resp

17 Results: After (DFIG, low load)

18 Results: DFIG with Psdn2_1 N-1Low Load <1% V change at each bus

19 Results: DFIG with Psdn4_2 N-1Low Load <1% V change at each bus

20 Results: DFIG rejection Low Load <1% V change at each bus

21 Results: Fault Currents (max only) Before After S/gear kv/ka 1-ph 3-ph 1-ph 3-ph Min. Posdn Posdn Psdn Cookh Cookh ph contribution Psdn1: Cookh1=1.4kA 3-ph contribution Psdn1: Cookh1=2.6kA C-factor = 1.1, Gen Xsource=X_subtrans=0.2 (0.33 for Fully Rated) Trfr taps ratios and phase shift angles unchanged FACTS devices blocked

22 Technical Solution Equipping of either spare 132kV feeder 2 or 3 at Poseidon Tx scope is 100% shallow, no deep scope of work Project status: Budget quote in progress, 1 st site meeting held last week. Eskom team to be in contact regards: - Type of protection - Telecommunication requirements - Metering specifications - Self-build option for 132kV line or not - Tx timeframe of months from acceptance of budget quote

23 Summary Generator impact on Poseidon network is minimal (adequately compensated area so possible voltage concerns manageable & gen relatively close to MTS). Poseidon switchgear ratings adequate to clear busbar faults (max I f ). Dynamic study at project level and LVRT to be conducted for completeness purposes: dyn. justified at system level once final turbine size known (influences gen model chosen) and LVRT done by generator. Proposed 140MW generator meets the tested planning criteria based on unity power factor control. Question: Eskom would like to know how the developer will comply with the SAGC requirements (eg. LVRT) since a type 2 generator does not have this capability?

24 Poseidon SLD