Updates on International Grid Codes

DIgSILENT Home Office Updates on International Grid Codes!" #$ $!%" &"!'(") *+,! (! *+,!%! '-%) *!+ ',!) *!+.! ++!!* (!% by DIgSILENT Ibérica Techwindgrid 09 20/21 April 2009, Madrid DIgSILENT Ibérica, S.L. 21.04.2009 2 DIgSILENT Group Activities,! * %. $ / 01 +,+ * -+2+,! /!%!"! (#++,! &!% 0 3,,!* %!%4!* " -%! #(5 4% -! &5 &5 %" -+ *+ -! &5 -($ 3 $6!% "! -%! /*%7 &!!%8!*! +, -!! 9! %*+++ *!!"!!,%% (4! *!!!1##* /!!!% -+ / / +0 :!%"!"! +,* -+2 /**%! '! ;, :!! &!! <6!!*,!!= >*!)!!!* &$ '= (60!" / 3/ %**) 6!" 3 6* 3 %!* & $ (?$, (! /%! /,?, +,+-+!*,!!,% #!*-!*+@ -+ <! % <" + 68%!*?% ;1!! <4 1 /! - - # /-- ;* <* @ %!*!!* 2 (6 % *+ DIgSILENT Ibérica, S.L. 21.04.2009 3 6!!*6!!A! "# -%!* $! #(6 " * # " #!3! DIgSILENT Ibérica, S.L. 21.04.2009 4 1

1000.00 800.00 600.00 400.00 200.00 0.00 2.0E+3 1.0E+3 0.0E+0-1.0E+3 10000 [s] 100 1 0.01 0.40 kv 100 1000 10000 100000 1000000 [pri.a] 10000000 20.00 kv 1.00 5.00 7.00 11.0 13.0 17.0 19.0 23.0 25.0 29.0 31.0 [-] D-3: Current, Magnitude in A D-4: Current, Magnitude in A T-BL_UW3: Current, Magnitude/HV-Side in A -2.0E+3-0.00 0.02 0.04 0.06 0.08 [s] D-3: Current in A D-4: Current in A T-BL_UW3: Current/HV-Side in A Masterpac MP M20H1/800A 10.588 s 0.687 s OC-Relay Type I>/I>> Fuse 300 A A055C300E 10 100 1000 10000 100000 Motor 1 SS-T/T-LV SS-L2/SS-T Cub_2\I>I>>_Trafo Cub_2\Motor Relay Cub_2\Fuse Cable 0.10 DIgSILENT PowerFactory DIgSILENT #$%& #/?*6!*!* %!!%" %! % 6 61 Iberian product: Testing system for wind farm and solar plants #!%!! BB B % I =1850.301 pri.a I =1821.774 pri.a I =113974.200 pri.a DIgSILENT #/%%! #@ #! DIgSILENT Ibérica, S.L. 21.04.2009 5 DIgSILENT Ibérica, S.L. 21.04.2009 6 Testing Centralized Voltage Controllers Testing Centralized Voltage Controllers PROJECT STAGE 1: Strategies definition Central Controller design Verification with simulation PROJECT STAGE 2: The same wind farm is used to test the controller implemented in c++. Interface PF-DLL Q CONTROL MODE 1 Total Total Qset Qset ( i) = number of available wind turbines Q CONTROL MODE 2 Q Total set ( i + 1) = Q ( i) Q Total set i set DIgSILENT Ibérica, S.L. 21.04.2009 7 DIgSILENT Ibérica, S.L. 21.04.2009 8 2

Testing Centralized Voltage Controllers Testing Centralized Voltage Controllers PROJECT STAGE 3: The same wind farm is used to test the controller implemented in c++ on an OPC server. Interface PF-OPC server. Wind Farm Controller: 1.075 1.050 1.025 U_SET_MAX 1.05 p.u. 1.15 1.10 1.05 1.00 U_WT_MAX 1.10 p.u. DIgSILENT 1.000 0.95 0.90 U_WT_MIN 0.90 p.u. 0.975 U_SET_MIN 0.95 p.u. 0.950 0.925 13.88 64.08 114.3 164.5 214.7 [s] 264.9 2-Winding Transformer: Tensión, Magnitud/Lado HV in p.u. 2-Winding Transformer: Tensión, Magnitud/Lado LV in p.u. 0.85 13.88 64.08 114.3 164.5 214.7 [s] 264.9 WT1: Tensión, Magnitud in p.u. WT2: Tensión, Magnitud in p.u. WT3: Tensión, Magnitud in p.u. WT4: Tensión, Magnitud in p.u. WT5: Tensión, Magnitud in p.u. WT6: Tensión, Magnitud in p.u. WT7: Tensión, Magnitud in p.u. 3.00 0.30 2.00 0.20 0.10 1.00 0.00 0.00-0.10-1.00-2.00-3.00 13.88 64.08 114.3 164.5 214.7 [s] 264.9 2-Winding Transformer: Posición Actual del Tap -0.20 13.88 64.08 114.3 164.5 214.7 [s] 264.9 DIgSILENT Ibérica, S.L. 21.04.2009 9 DIgSILENT Ibérica, S.L. 21.04.2009 10 Updates on International Grid Codes Grid Codes: Short worldwide overview DIgSILENT Ibérica, S.L. 21.04.2009 11 DIgSILENT Ibérica, S.L. 21.04.2009 12 3

MINIMOS DE DISEÑO, EQUIPAMIENTO, FUNCIONAMIENTO, PUESTA EN SERVICIO Y SEGURIDAD Current version: April 2009 SPAIN DIgSILENT Ibérica, S.L. 21.04.2009 13 Status: Under discussion Starting from: 01/01/2011 (or 2012) Applicable to: - Generation connected to HV network - Generation connected to MV network if P>10MW - Distributed generation sharing the same connection point if P grouped >10MW New features: - Power quality limits - Distinction between directly coupled Sync. Generators, WP and PV - Power and Voltage regulation requirements at PCC level - Requirements on negative sequence currents - Islanding features DIgSILENT Ibérica, S.L. 21.04.2009 14 General Power Quality Requirements: Flicker According to IEC61000-3-7 Harmonics According to IEC 61000-3-6 Unbalance Planning level Pst1.0 Plt0.8 THD: 3.00% I - /I + 1% for short duration unbalance (>10 min) I - /I + 2% for very short duration unbalance (<10min) Emission limits Pst0.8 Plt0.6 THD: 3.00% I - /I + 0.7% for short duration unbalance (>10 min) I - /I + 1% for very short duration unbalance (<10min) DIgSILENT Ibérica, S.L. 21.04.2009 15 DIgSILENT Ibérica, S.L. 21.04.2009 16 4

Low Voltage Ride Through: - Capability to stay connected in case of 3PH/1PH voltage dip 0% duration 1 second. - Capability to stay connected in case of 2PH voltage dip 0.5% duration 1 second. - Capability to stay connected in case of phase shift 30º -Reactive power support controlled by AVR Overvoltage Ride Through: -3PH/2PH/1PH figure -Occasionally, up to 125% if voltage was 110% -Reactive power support controlled by AVR DIgSILENT Ibérica, S.L. 21.04.2009 17 DIgSILENT Ibérica, S.L. 21.04.2009 18 Frequency disturbances: - Capability to stay connected unless f < 48 Hz during 3 seconds or more - Instantaneous disconnection if f < 47.5 Hz - Capability to stay connected if f reaches 51.5 Hz - Capability to stay connected during df/dt < ±2Hz/second. Frequency regulation: - Primary regulation mandatory - PSS mandatory when rated power P>50MW DIgSILENT Ibérica, S.L. 21.04.2009 19 DIgSILENT Ibérica, S.L. 21.04.2009 20 5

Islanding: - Coordination with MV islanding protections to avoid unneeded disconnection. - New thermal units are requested to stay connected on islanding mode + auxiliary services. - New hydro + pumping units are requested to provide: - self-starting - auto-energization - islanding regulation capabilities. Voltage regulation: - A Voltage deadband setpoint will be provided by the operator. - Voltage error inside the deadband. - Q regulation capability 0P rated. - Out of margins 1-V V 1+V, as allowed by P produced. DIgSILENT Ibérica, S.L. 21.04.2009 21 DIgSILENT Ibérica, S.L. 21.04.2009 22 Low voltage ride through: - 3PH faults as in the figure - 2PH faults 0.5 and 0.6 p.u. instead Phase shift ride through: -Capability to stay connected in case of phase shift 30º DIgSILENT Ibérica, S.L. 21.04.2009 23 DIgSILENT Ibérica, S.L. 21.04.2009 24 6

Overvoltage ride through: - 3PH/2PH/1PH as in the figure - Occasionally, up to 125% if voltage was 110% - Power Electronic Converters can be blocked if V>125% providing I r =0 p.u. - Reactive power support controlled by AVR Voltage regulation during disturbances: - Voltage support during distubances I max = I rated - Voltage regulation provided by an AVR during disturbances: - To maintain Vsetpoint = Vprior to the disturbance - In case of unbalance, positive seq voltage - In operation when V is out of normal operation range. - Reactive current absorption/injection as in the next slide DIgSILENT Ibérica, S.L. 21.04.2009 25 DIgSILENT Ibérica, S.L. 21.04.2009 26 Power regulation during disturbances: DIgSILENT Ibérica, S.L. 21.04.2009 27 DIgSILENT Ibérica, S.L. 21.04.2009 28 7

Requirements during the disturbances: - Limits on P, Q consumption as in P.O.12.3, during the dip and after the dip - NEGATIVE SEQUENCE CONTRIBUTION (not a requirement yet, to be discussed and fixed according to the network requirements) Frequency disturbances: - Capability to stay connected unless f < 48 Hz during 3 seconds or more - Instantaneous disconnection if f < 47.5 Hz - Capability to stay connected if f reaches 51.5 Hz - Capability to stay connected during df/dt < ±2Hz/second. - Coordination with MV islanding protections to avoid unneeded disconnection. DIgSILENT Ibérica, S.L. 21.04.2009 29 Frequency regulation: - Primary regulation mandatory P / M K = f / f base base -Time response: 1-30 sec or inertial response emulation if agreed with the TSO. -PSS damping, to be agreed with the TSO DIgSILENT Ibérica, S.L. 21.04.2009 30 Frequency regulation: - Primary regulation mandatory P / M K = f / f base base MINIMOS The WF DE DISEÑO, should guarantee EQUIPAMIENTO, FUNCIONAMIENTO, PUESTA the EN reserve SERVICIO availability Y SEGURIDAD related to wind speed Specificto requirements: be able to increase 2) Wind, Produced solar and Power other power plants without a (exception if Pproduced<20%) GERMANY -Time response: 1-30 sec or inertial response emulation if agreed with the TSO. -PSS damping, to be agreed with the TSO DIgSILENT Ibérica, S.L. 21.04.2009 31 DIgSILENT Ibérica, S.L. 21.04.2009 32 8

Germany Germany Operator: Technische Richtlinie. Erzeugungsanlagen am Mittelspannungsnetz (Richtlinie Anschluss und Parallelbetrieb von Erzeugungsanlagen Mittelspannungsnetz) Operator: Technische Richtlinie. Erzeugungsanlagen am Mittelspannungsnetz (Richtlinie Anschluss und Parallelbetrieb von Erzeugungsanlagen Mittelspannungsnetz) für am für am By: BDEW, Bundesverband der Energie- und Wasserwirtschaft e.v. By: BDEW, Bundesverband der Energie- und Wasserwirtschaft e.v. Network: Distribution level Network: Distribution level Frequency regulation as in 2007 Transmission Grid Code TYPE 2 TYPE 1 DIgSILENT Ibérica, S.L. 21.04.2009 TYPE 2 33 DIgSILENT Ibérica, S.L. 21.04.2009 34 21.04.2009 36 Germany Operator: Technische Richtlinie. Erzeugungsanlagen am Mittelspannungsnetz (Richtlinie Anschluss und Parallelbetrieb von Erzeugungsanlagen Mittelspannungsnetz) für am By: BDEW, Bundesverband der Energie- und Wasserwirtschaft e.v. Network: Distribution level DENMARK Reclosing DIgSILENT Ibérica, S.L. 21.04.2009 35 DIgSILENT Ibérica, S.L. 9

Denmark Denmark Operator: EnergyNet.dk Network: Distribution level (< 100kV) Particularity: Double Disturbance Operator: EnergyNet.dk Network: Distribution level (< 100kV) Particularity: Double Disturbance. Capacity to stand: - Two 2PH/3PH Short Circuit within a 2 min interval - Energy reserve enough to stand SIX 2PH/3PH Short Circuits within 5 min interval DIgSILENT Ibérica, S.L. 21.04.2009 37 DIgSILENT Ibérica, S.L. 21.04.2009 38 Denmark Denmark Operator: EnergyNet.dk Network: Transmission level (> 100kV) Particularity: For Wind Farms: - 3PH short circuit 100ms - 1/2PH short circuit 100 ms, followed by a new one after 300-500ms For Wind Turbine: - Two 1/2/3PH Short Circuit within 2 min interval - Energy reserve for SIX 1/2/3 PH short circuit with 5 min interval. Operator: EnergyNet.dk Network: Transmission level (> 100kV) Particularity: SIMULATIONS - Slow voltage recovery DIgSILENT Ibérica, S.L. 21.04.2009 39 DIgSILENT Ibérica, S.L. 21.04.2009 40 10

Denmark Operator: EnergyNet.dk Network: Transmission level (> 100kV) Particularity: SIMULATIONS - Unbalance and reclosure CHINA DIgSILENT Ibérica, S.L. 21.04.2009 41 DIgSILENT Ibérica, S.L. 21.04.2009 42 China China Grid Code: Technical Rule for Connecting Wind Farm into Power Network By: State Grid Corporation / China Electric Power Research Institute Network: Voltages above 100(66) kv Primary control mandatory: setpoints will be sent by the operator. Recommendations on the power ramp rate during: - Cut in / Shut down - Increasing wind speed (not mandatory during wind speed decrease) - Maximum power rate can be discussed with the operator LVRT Requirements: Grid Code: Technical Rule for Connecting Wind Farm into Power Network By: State Grid Corporation / China Electric Power Research Institute Network: Voltages above 100(66) kv The installed capacity of wind farm (MW) <30 30-150 >150 10min maximum ramp rate (MW) 20 installed capacity /1.5 100 1min maximum ramp rate (MW) 6 installed capacity /5 30 -Emergency control: capability of reducing power when f>50.5hz, even disconnect. DIgSILENT Ibérica, S.L. 21.04.2009 43 DIgSILENT Ibérica, S.L. 21.04.2009 44 11

China China Frequency limits: Grid Code: Technical Rule for Connecting Wind Farm into Power Network By: State Grid Corporation / China Electric Power Research Institute Network: Voltages above 100(66) kv Range of frequency Below 48Hz 48Hz 49.5Hz 49.5Hz 50.5Hz 50.5Hz 51Hz Above 51Hz Requirements According to the permissible lowest operation frequency of the wind turbine. Maintaining continues operation for 10 min at least when frequency is lower than 49.5Hz Operating continuously. Maintaining continues operation for at least 2 minutes whenever frequency is above 50.5Hz, and no more shutting wind turbine cutting-in. Limit the output power with the order of the dispatching department. Grid Code: Technical Rule for Connecting Wind Farm into Power Network By: State Grid Corporation / China Electric Power Research Institute Network: Voltages above 100(66) kv Power Quality issues: Voltage deviations: V<10%Vrated. In general -3%Vrated<V<7%Vrated Voltage variations: The number of voltage variations per unit time R h d -1 10 r 100 100 r 1000 Flicker: It should meet the requirements stated in GB 12326-2000. Plt and Pst will be allocated depending on the short circuit power of the network. Harmonics: It should meet the requirements stated in GB / T 14549-1993. Harmonic emission levels should be allocated depending on the short circuit harmonic power of the network. R 1 1 r 10 3 2.5 1.5 1 DIgSILENT Ibérica, S.L. 21.04.2009 45 DIgSILENT Ibérica, S.L. 21.04.2009 46 China Conclusions Grid Code: Technical Rule for Connecting Wind Farm into Power Network By: State Grid Corporation / China Electric Power Research Institute Network: Voltages above 100(66) kv Simulations: -Wind Farm developers will provide models (PowerFactory DIgSILENT) which include: - parameters of wind turbines. - wind farm layout - wind turbine/wind farm control system - Maintenance/Update of models should be guaranteed by the Wind Farm Developer. More and more restrictive requirements are arising in many countries. Trend Simulation procedures to test/verify at wind farm level Towards harmonization?? DIgSILENT Ibérica, S.L. 21.04.2009 47 DIgSILENT Ibérica, S.L. 21.04.2009 48 12

Conclusion DIgSILENT Ibérica, S.L.: Contacto DIgSILENT Ibérica S.L. C\ Honduras, 8 - Bajo 3 28016 Madrid Phone: +34 911273723/24 Email: a.morales@digsilent.com x.robe@digsilent.com Website: www.digsilent.com DIgSILENT Ibérica, S.L. 21.04.2009 49 DIgSILENT Ibérica, S.L. 21.04.2009 50 13