SOME NSW SYSTEM PLANNING ISSUES. Dr Col Parker Manager/System Planning & Analysis

Transcription

1 SOME NSW SYSTEM PLANNING ISSUES Dr Col Parker Manager/System Planning & Analysis

2 David Hill s Contributions from a NSW planning perspective Dynamics of voltage collapse Modelling of loads and load dynamics Direct methods of transient stability Stability - theory Excitation system control Power system analysis Contributions via: Papers Discussion Joint R&D work with TransGrid Research leader to later generations

3 Contents Background - NSW system 500 kv system developments Damping issues Wind generation Load dynamics Transient stability capability Diverse sources of generation

4 Background - NSW main system

5 NSW is part of the interconnected eastern Australian electricity system 4800 km AC mainland system HVDC link NSW - Qld HVDC link Vic - SA HVDC cable To Tasmania

6 Forecast power demands (MW) summer 2009/ Qld NSW Vic SA Tas

7 NSW main system Lismore Load 15,000 MW Coal fired generation 11,900 MW Gas turbines 1,800 MW Snowy import 3200 MW Import from Qld 1250 MW Tamworth Armidale Coffs Harbour 500, 330, 220, 132 kv Transmission (12500 km) Wellington Mt Piper/W Wang Muswellbrook Liddell/Bayswater Newcastle Eraring/Vales/Munmorah Tuggerah Sydney Jindera Wagga T3 Bannaby Marulan Yass Canberra T1/T2 Murray Wollongong Kangaroo Valley

8 Major power station centres Lismore Armidale Coffs Harbour Tamworth Wellington Muswellbrook Liddell/Bayswater Mt Piper/W Wang Bannaby Marulan Yass Wagga Canberra T3 Jindera T1/T2 Murray Newcastle Eraring/Vales/Munmorah Tuggerah Sydney Wollongong Kangaroo Valley Coal GTs Snowy hydro

9 Mt Piper Power Station (2 x 700 MW units)

10 Tallawarra GT station (422 MW co-generation)

11 Interconnection capability (MW) Up to 400 Lismore To 1250 Armidale Coffs Harbour Tamworth Wellington Muswellbrook Liddell/Bayswater Mt Piper/W Wang Newcastle Eraring/Vales/Munmorah Tuggerah Sydney Bannaby Marulan Yass Wagga Canberra T3 Jindera T1/T2 Murray Wollongong Kangaroo Valley Transfer limitations: Line ratings Voltage control Response to large disturbances Damping of small oscillations

12 500 kv Developments

13 To Northern NSW and QLD Wellington Muswellbrook Liddell /Bayswater Newcastle Mt Piper / Wallerawang Eraring / Vales Pt/ Munmorah Tuggerah Sydney Marulan Wollongong Yass Kangaroo Valley Canberra Lower Tumut Upper Tumut Murray To Victoria Present Core System

14 Wellington To Northern NSW and QLD Bayswater Muswellbrook Liddell Newcastle Mt Piper / Wallerawang Bannaby Sydney Eraring / Vales Pt/ Munmorah Tuggerah Western 500 kv Upgrade Yass Marulan Wollongong Kangaroo Valley (Complete early 2010) Canberra Lower Tumut Murray Upper Tumut To Victoria Legend 330 kv Switchyard / Substation 330 kv Line 500 kv Line Operating at 330 kv

15 Lismore Power from Queensland Armidale Coffs Harbour Tamworth Power from Wellington NSW Generators Jindera Wagga T3 Mt Piper/W Wang Yass Murray T1/T2 Marulan Canberra Muswellbrook Liddell/Bayswater Sydney Wollongong Kangaroo valley Newcastle Eraring/Vales/Munmorah Tuggerah Power from Victoria and Snowy 10,000 MW 75% of NSW Demand 1/3 rd of NEM demand

16 Volts pu Voltage control Line trip 132 kv 330 kv Seconds Sydney voltage levels

17 Emerging Issues Part of the need for system reinforcement is to provide adequate voltage control Voltage stability determined by the dynamic response of the load to disturbances Potential to co-ordinate control of generators, SVCs and capacitor bank switching New SVCs how much reactive support needs to be dynamic and how much can be static

18 To Northern NSW and QLD Wellington Bayswater Liddell Newcastle Mt Piper / Wallerawang Sydney Eraring/ Vales Pt / Munmorah Yass Bannaby Marulan Wollongong Lower Tumut Upper Tumut Murray To Victoria Canberra Bannaby Sydney 500 kv

19 System Oscillatory Damping QNI QLD NSW SA VIC Dederang First Synchronisation of Queensland System 1/12/2000

20 190 First synchronisation on QNI MW Seconds Measured Measured power power flow flow on on one one Dederang Dederang --South South Morang Morang 330kV 330kV circuit circuit in in Victoria Victoria at at the the time time of of the the first first synchronisation synchronisation of of Queensland Queensland to to the the rest rest of of the the eastern eastern Australian Australian system. system.

21 Springs and masses analogy Central Queensland Port Augusta Southern Queensland Hunter Valley Central Coast Central West 275kV Brisbane 330kV 500/330 kv Sydney Adelaide Adelaide Metro 275kV Melbourne 500kV Canberra Snowy Hydro Latrobe Valley

22 Damping - Progress Interconnector testing has been undertaken over last 8 years to understand the damping issues and to measure the damping Steady-state stability modelling indicates that the damping should be better than as measured. Generator Power System Stabilisers have been tuned Power Oscillation Dampers fitted to SVCs near QNI QUT and Don Geddey s work on deriving damping information from continuous voltage-angle measurements from GPS-synchronised on-line recorders at: South Pine in Qld, Sydney West in NSW, Rowville in Victoria; and Para in South Australia On-line measurement is based on the QUT/Geddey (TransGrid) algorithm

23 Sample magnitude Magnitude spectra spectra of Sydney of (S B) dθ/dt Brisbane signals during voltage-angle 28 29/5/02 differences :00 14:00 28/5 18:00 22:00 28/5 02:00 06:00 29/5 8 7 SYDNEY - BRISBANE Magnitude of FT Frequency (rad/s)

24 Sample magnitude spectra of Melbourne - Adelaide voltage-angle differences 7 Magnitude spectra of (M A) dθ/dt signals during 28 29/5/ :00 14:00 28/5 18:00 22:00 28/5 02:00 06:00 29/5 Magnitude of FT Melbourne Adelaide Frequency (rad/s)

25 3.5 rad/sec mode eigenvectors (speed states) Victorian vs SA generators Queensland generators SA generators Victorian generators NSW generators

26 2.5 rad/sec mode eigenvectors (speed states) NSW vs SA & Qld generators NSW generators Queensland generators SA generators Queensland generators

27 1.8 rad/sec (QNI) mode eigenvectors SA & Victoria vs Qld generators Queensland generators Victorian generators SA generators

28 11/03 0:00 10/03 12:00 QNI(1.8 rad/s) mode damping (measured and simulated) 10/03 0:00 9/03 12:00 9/03 0:00 8/03 12:00 8/03 0:00 7/03 12:00 7/03 0:00 6/03 12:00 6/03 0:00 5/03 12:00 5/03 0:00 4/03 12:00 4/03 0:00 3/03 12:00 3/03 0:00 2/03 12:00 2/03 0:00 1/03 12:00 1/03 0: No damping Measured Modelled real part (Np/s) 0.9 Original Data OSM Well damped

29 Continuing work Complete checking of all NEM generator models Switching the SVC Power Oscillation Dampers on and off to measure their impact Analysis to estimate the effectiveness of the generator Power System Stabilisers and SVC Power Oscillation Dampers

30 11/03 0:00 QNI(1.8 rad/s) mode damping(measured and modified simulated) Measured Modelled with modifications 10/03 12:00 10/03 0:00 9/03 12:00 9/03 0:00 8/03 12:00 8/03 0:00 7/03 12:00 7/03 0:00 6/03 12:00 6/03 0:00 5/03 12:00 5/03 0:00 4/03 12:00 4/03 0:00 3/03 12:00 3/03 0:00 2/03 12:00 2/03 0:00 1/03 12:00 1/03 0: real part (Np/s) Modified Paramater: Glad PSS: 0.42; Blackwall POD: 0.38 OSM

31 Wind generation connection and impact

32 WIND FARM RESOURCE LOCATIONS FNQ Far North Queensland NQ North Queensland CQ Central Queensland SWQ South West Queensland FWN Far West NSW MRN Murray NSW SEN South East NSW WN West NSW MRN Marulan NSW HUN Hunter NSW NEN New England NSW FNQ NQ NEM wind areas NWV North West Victoria SWV South West Victoria SEV South East Victoria CQ CS Central South WCS West Coast SA EPS Eyre Peninsula SA YPS Yorke Peninsula SA MNS Mid North SA FLS Fleurieu SA SWQ NWT North West TAS NET North East TAS WCT West Coast TAS ST Southern TAS FWN NEN WCS MNS HUN EPS YPS MRN WEN FLS NWV MRN SWV SEN CS SEV NWT NET WCT ST

33 NSW wind areas FWN NEN HUN WEN MRN MRN SEN

34 NSW wind Farms operating 170 MW Lismore Armidale Coffs Harbour Tamworth Wellington Muswellbrook Liddell/Bayswater Cullerin Range 30 MW Mt Piper/W Wang Marulan Yass Wagga Canberra T3 Jindera T1/T2 Murray Sydney Wollongong Kangaroo valley Newcastle Eraring/Vales/Munmorah Tuggerah Capital 141 MW

35 Wind Farms inquiries to TransGrid (> 4500 MW) Lismore Armidale Coffs Harbour 1200 MW >1000 MW Tamworth Wellington Mt Piper/W Wang Muswellbrook Liddell/Bayswater Newcastle Eraring/Vales/Munmorah Tuggerah Sydney 900 MW Wagga Yass Marulan Wollongong Kangaroo valley 1600 MW Canberra Jindera T3 T1/T2 Murray

36 Wind generation import to NSW Lismore Armidale Coffs Harbour Tamworth Wellington Muswellbrook Liddell/Bayswater Import from Victoria and South Australia Mt Piper/W Wang Marulan Yass Wagga Canberra T3 Jindera T1/T2 Murray Cullerin Range 30 MW Newcastle Eraring/Vales/Munmorah Tuggerah Sydney Wollongong Kangaroo valley Capital 141 MW

37 TransGrid Wind Farm planning activities Assessing connection applications System planning is based on scenario analysis for the future this includes wind farm development scenarios across NSW Other work on: Network modelling and wind traces for market simulations Developing a wind expansion plan from the market modelling Aim in the longer-term to rank sites according to connection costs, deep network costs and generation revenue

38 Typical wind farm generation duration curve 100 % of installed capacity % of energy output above 75% of capacity % of time Output at time of NSW peak demand

39 Wind Farm performance with system disturbances Wind Farm Main system loads HV bus LV bus

40 Wind Farm MW output HV bus fault LV bus fault

41 Wind Farm voltage HV bus fault LV bus fault Wind farm trips

42 Planning issues for wind farm connection How much transmission should we build to: connect wind farms, transfer power to the load; and import wind energy to NSW Capability of single wind farms to ride through faults NSW system-wide impact of high wind penetration (ride through and inertia) Statcoms / SVCs distributed or centralised

43 Load Dynamics Planning studies range from steady-state analysis to dynamic analysis Example of supply to a paper mill load in NSW

44 Wagga 330/132 kv substation 132 kv system Rural substation Yass 330/132 kv substation 80 km 10 km 90 km Paper mill substation External parallel 330 kv and 132 kv system

45 132 kv system 42- j41 39-j3 80 +j25 Paper mill substation Normal power flows

46 Outage of a 132 kv line Steady-state QE relationship Before tap changers operate Mvar generation After tap changers operate Volatge pu Voltage indices 1 and 3

47 Line opening without a fault Voltage (pu) Rural substation 132 kv bus Paper mill 11 kv Time (cycles)

48 Reactive power demand at the supply point Reactive power (per unit) Time (seconds)

49 3-phase fault on a connecting 132 kv line Voltage (per unit) Rural substation 132 kv bus 0.2 Paper mill 11 kv Time (cycles)

50 3-phase fault remote 132 kv line Rural substation 132 kv bus Voltage (oer unit) Paper mill 11 kv Times (cycles)

51 Transient Stability Capability Transient stability governs power transfer capability at times: From NSW to Queensland Queensland to NSW NSW to Victoria / SA Victoria to NSW Also necessary to ensure that: Line protection systems are adequate within NSW to avoid degradation of inter-state transfer limits; and Subsystem lines do not trip during system swings.

52 Analysis Detailed generator modelling Loads represented by composite models including induction machines Detailed network model Numerous critical disturbances with different outcomes Expected fault clearance times Applies a time domain simulation of algebraic-differential equations describing the network and machine dynamics Modes of instability system separation along different network cutsets

53 Present load model HV LV Impedance Bus at 1pu voltage Induction motor Resistive load Saturation Shunt capacitors

54 Technical envelope NSW to Queensland Limit with safety margin NSW to Victoria Stable region Victoria to NSW Queensland to NSW

55 Hunter Valley 330 kv line fault 780 MW Lismore 2-phase line-to-ground fault Tamworth Armidale Coffs Harbour Wellington Muswellbrook Liddell/Bayswater Mt Piper/W Wang Newcastle Eraring/Vales/Munmorah Tuggerah Sydney Jindera Wagga T3 Bannaby Marulan Yass Canberra T1/T2 Murray Wollongong Kangaroo Valley

56 Generator rotor angles Bayswater 40 Angle (degrees) Tarong (in Qld) -80 Time (sconds)

57 Outcome is dependent on: Fault clearance times (protection and circuit breaker) Generator inertia (including embedded sources) Excitation system performance Load drop compensation setting Load modelling Generator models need to match reality

58 Delayed fault clearance - unstable outcome 100 Bayswater 50 Angle (degrees) Tarong (in Qld) Time (seconds)

59 Stability outcomes are dependent on system parameters Angle difference (degrees) Time (seconds) Nominal trajectory

60 Uncertainties and sensitivities Ian Hisken s work on Trajectory Sensitivity Identify variations from the nominal trajectory of the system following a disturbance Ranking relative influence of parameters (load and generator) Setting safety margins

61 Issues with diverse generation Wind farm models developed by proponents (translated to models to match TransGrid software) Reactive supply (wind farms vs coal-fired stations) Wind farm ability to ride-through line faults Wind displacing coal inertia impacts on transient stability High penetration implies variable flows what voltage control is required? Interconnection capability and variable flows from the south of NSW Future load modelling with embedded generation Transmission investment how much and when? Line ratings correlation with wind output Opportunities to maximise capability by co-ordinating controls Technical envelope: Extra variables Renewables and controls must be modelled (or can simplified equivalent models be used?)

62 The light on the hill Full understanding of load parameters for transient stability, voltage control, steadystate stability Co-ordinated control of diverse sources maximising power transfer capability Direct methods of transient stability ability to directly define the technical envelope Damping modelled outcome to match measured