Simulations and Tests of a Danish Smartgrid The Cell Controller Pilot Project

Transcription

1 Simulations and Tests of a Danish Smartgrid The Cell Controller Pilot Project September 2017 E. Tröster, T. Ackermann, N. Martensen (Energynautics, Germany) Contact: E.Troester@energynautics.com In Cooperation with

2 DEVELOPMENT IN THE DANISH POWER SYSTEM Source: Energinet.dk 2

3 IDENTIFIED TARGETS OF THE REDESIGN PROCESS Increased security of supply Sufficient domestic resources must be available to maintain a balance between demand and generation Improved operator knowledge of actual system conditions both locally and centrally Efficient system control particularly during emergencies Active usage of distributed generators Black starting capabilities using distributed generators Organising distributed generators into controllable Virtual Power Plants 3

4 150 kv 150 kv Input Cell controller Output 60 kv 60 kv 60 kv 60 kv 10 kv 10 kv 10 kv 60 kv 60 kv 60 kv 10 kv 10 kv 60 kv 10 kv 4

5 THE CELL CONTROLLER 5 5

6 PILOT CELL: HOLSTED 60 KV GRID AREA Installed CHP: 37 MW Installed Wind: 39 MW Max Load: 61 MW 150/60 kv Trafo: 100 MVA Test Area 1 8,8 MW G 2 MW G Wind BIO BID BIS MØR 4 MW Wind 7 MW ÅRR AGB 3,3 MW Wind VOB LIK 2 MW Wind GLE HOD Wind 2 MW REV G 15,5 MW BMØ GØR HOS FØV G 3 MW 3,8 MW G BRØ Wind 2 MW VJV Wind 3,6 MW 6

7 CELL CONTROLLER CONCEPT Each Cell can be regarded as a Virtual Generator with same or better controllability compared to a traditional power station unit of equal size Local distribution companies attain strongly increased possibilities of distribution network online monitoring and active control Automatic Cell transition to controlled island operation in case of imminent transmission system break-down Black-start of transmission system Robust Cell Controller Concept designed to encompass all new types of DG units and controller functionalities Increase in security of supply Any new functionality as pure software development Re-design for the future Danish electric power system 7

8 LEVEL OF FUNCTIONALITY OF THE CELL CONTROLLER Monitoring total load and production within the Cell Active power control of synchronous generators Active power control of wind farms and large wind turbines Reactive power control by utilising capacitor banks of wind turbines and grid Voltage control by activating AVRs on synchronous generators Frequency control by activating SGSs on synchronous generators Capability of operating 60 kv breaker on 150/60 kv transformer Capability of operating breakers of wind turbines and load feeders Automatic fast islanding of entire 60 kv Cell in case of severe grid fault Automatic fast generator- or load shedding in case of power imbalance Voltage, frequency and power control of islanded Cell Synchronising Cell back to parallel operation with the transmission grid Black-starting support to transmission grid in case of black-out 8

9 CHPS IN TEST AREA 1 Billund: 3x 3.6 MVA Hejnsvig: 2x 1.3 MVA 9

10 WINDTURBINES IN TEST AREA 1 4x 1000 kw Windturbine NEG Micon NM60/1000 Monitoring 10

11 SYNCHRONOUS CONDENSER AND DUMP LOAD (SLC) 800 kva synchronous condenser for voltage control 1000 kw dump load for frequency control 11

12 SIMULATION: ISLANDOPERATION WITH WINDTURBINES Islanding Resynchronisation Frequency DIgSILENT Active Power Reactive Power [s] GridBreaker:ActivePowerImportinMW GridBreaker:ReactivePowerImportinMvar [s] GridBreaker:ElectricalFrequency/Terminali GridBreaker:ElectricalFrequency/Terminalj Frequency Dip 12

13 SIMULATION: DUMP LOAD (SLC) DIgSILENT 0.75 Active Power 1.02 Frequency Voltage [s] SLCLoadbank:TotalActivePowerinp.u. SLCBLControl:Setpoint SLCBLSetpointCalc:CtlSetpoint [s] SLCLoadbank:ElectricalFrequency SLCLoadbank:Voltage,Magnitudeinp.u

14 SIMULATION: WINDTURBINE Active Power Reactive Power [s] Trf 50366: Psum WT1 Trf 50366: Qsum WT1 Switching of capacitor bank

15 SIMULATION: SYNCHRONOUS CONDENSER Frequency DIgSILENT Active Power Voltage [s] Synchronous Condenser: Total Active Power in p.u [s] Synchronous Condenser: Electrical Frequency Synchronous Condenser: Voltage, Magnitude in p.u Reactive Power Switching of 1.50 capacitor bank [s] Synchronous Condenser: Total Reactive Power in p.u. Qctrl: Ref [s] Selector: ic Synchronous Condenser: Current, Magnitude in p.u

16 MEASUREMENT RESULTS VOB AGB Cell Controller STI BIS Hejnsvig Billund BID KT21 KT22 KT21 KLN GLB FUG CHP TRØ GRØ KVV MØL CEN SØK Mini Island GEN1 GEN2 SC SLC WT1 WT2 WT3 WT4 BID GEN1 BID GEN2 BID GEN3 60 kv 10 kv 0,4 kv 16

17 MEASUREMENT TEST 1: MINI ISLAND FREQUENCY 17

18 MEASUREMENT TEST 1: MINI ISLAND VOLTAGE 18

19 MEASUREMENT TEST 2: ISLAND OPERATION VOB AGB Cell Controller STI BIS Hejnsvig Billund BID KT21 KT22 KT21 KLN GLB FUG CHP TRØ GRØ KVV MØL CEN SØK GEN1 SC SLC WT1 WT2 WT3 BID GEN1 60 kv 10 kv 0,4 kv 19

20 MEASUREMENT TEST 2: ISLAND OPERATION FREQUENCY At time of island, cell generation (which includes over 1 MW of wind power) exceeds load by 470 kw. Frequency increases immediately, but SLC and CHP governors react to compensate. During island, cell frequency fluctuates as wind generation varies from 800 to 1350 kw. Cell Controller reacts and maintains cell within all grid code given boundaries. Cell reconnected to grid. 20

21 MEASUREMENT TEST 2: ISLAND OPERATION SYNCHRONIZATION Once a reconnection to the grid is requested, the Cell Controller brings cell frequency and voltage phase within range of grid values. The Master Synchronizer reconnects only when cell frequency and voltage phase are sufficiently close to the grid values. 21

22 MEASUREMENT TEST 3: IMPORT/EXPORT CONTROL VOB AGB Cell Controller STI BIS Hejnsvig Billund BID KT21 KT22 KT21 KLN GLB FUG CHP TRØ GRØ KVV MØL CEN SØK GEN1 WT1 WT2 WT3 BID GEN1 60 kv 10 kv 0,4 kv 22

23 MEASUREMENT TEST 3: IMPORT/EXPORT CONTROL Billund CHP Setpoint Actual value Hejnsvig CHP 1 hour 23

24 ACHIEVED TEST RESULTS Grid connected import/export control (virtual generator operation) Emergency transfer to sustained hybrid island operation Islanded wind only operation with SC and SLC 24

25 CONCLUSIONS A utility scale smart grid concept has been successfully demonstrated. Lessons learned from the project: By adding ICT to the system a higher security of supply can be achieved, however it also adds new sources of failure. Modelling and simulations are powerful tools to test new control strategies before going into the field. In case of island operation dynamic simulations are necessary! 25

26 THANK YOU FOR YOUR ATTENTION! 26