Virtual Inertia Emulation and Placement in Power Grids Institute - PowerPoint PPT Presentation

Acknowledgements Virtual Inertia Emulation and Placement in Power Grids Institute for Mathematics and its Applications Control at Large Scales: Energy Markets & Responsive Grids Florian D¨ orfler Bala Kameshwar Poolla Taouba Jouini Catalin Arghir Dominic Gross Saverio Bolognani 2 / 32 At the beginning of power systems was . . . Operation centered around bulk synchronous generation 50.02 50.02 f [Hz] f [Hz] Primary Control Tertiary Control 50.01 50.01 50.00 50.00 f - Setpoint 49.99 49.99 49.98 49.98 Secondary Control 49.97 49.97 49.96 49.96 PP - Outage Oscillation/Control 49.95 49.95 PS Oscillation 49.94 49.94 At the beginning was the synchronous machine : P generation 49.93 49.93 Mechanical Inertia M d 49.92 49.92 ω dt ω ( t ) = P generation ( t ) − P demand ( t ) 49.91 49.91 49.90 49.90 change of kinetic energy = instantaneous power balance 49.89 49.89 P demand 49.88 49.88 16:45:00 16:45:00 16:50:00 16:50:00 16:55:00 16:55:00 17:00:00 17:00:00 17:05:00 17:05:00 17:10:00 17:10:00 17:15:00 17:15:00 8. Dezember 2004 8. Dezember 2004 Fact: the AC grid & all of power system operation Frequency Mettlen, Switzerland Frequency Athens has been designed around synchronous machines. Source: W. Sattinger, Swissgrid 3 / 32 4 / 32

Distributed/non-rotational/renewable generation on the rise A few (of many) game changers . . . synchronous generator new workhorse scaling location & distributed implementation Almost all operational problems can principally be resolved . . . but one (?) Source: Renewables 2014 Global Status Report 5 / 32 6 / 32 Fundamental challenge: operation of low-inertia systems Low-inertia stability: # 1 problem of distributed generation We slowly loose our giant electromechanical low-pass filter: P generation 2001 2002 2003 2004 2005 2006 2007 2008 2009 30000 2010 M d 25000 ω dt ω ( t ) = P generation ( t ) − P demand ( t ) 20000 Duration [s] 15000 Events [-] 10000 change of kinetic energy = instantaneous power balance 5000 P demand 0 Number * 10 Months of the year # frequency violations in Nordic grid Number * 10 Duration 50 (source: ENTSO-E) same in Switzerland (source: Swissgrid) 49.8 M f [Hz] J 49.6 inertia is shrinking, time-varying, & localized, . . . & increasing disturbances 49.4 49.2 Solutions in sight: none really . . . other than emulating virtual inertia 49 through fly-wheels, batteries, super caps, HVDC, demand-response, . . . it 0 5 10 15 20 25 30 35 eal Time t [s] 7 / 32 8 / 32 15

Low inertia issues have been broadly recognized Virtual inertia emulation devices commercially available, required by grid-codes, or incentivized through markets by TSOs, device manufacturers, academia, etc. !""" #$%&'%(#!)&' )& *)+"$ ','#"-'. /)01 23. &)1 2. -%, 2456 5676 !"#$%&'"'() %* +$,(-.'() /'-#%(-' M assive I nte GRAT ion of power E lectronic devices !89:;8;<=><? />@=AB: !<;@=>B >< CD!EFGBH;I .( 0.1$%2$.3- 4-.(2 5.$)6,7 !('$)., +><I *JK;@ E;<;@B=>J< 8.".-9 :%(. ! "#$%&'# (&)*&+! ,--- ; :6$<,(,$,<,(, =%%77, ! (&)*&+! ,--- ; ,(3 06>67 ?@ ?9,(3%$>,$ ! (&)*&+! ,--- -JLB88BI@;MB DBNLB@> -J?LBIIB8 %@B<> ! "#$%&'# (&)*&+! ,--- . B<I "LBO D1 ":F'BBIB<P ! "&'./+ (&)*&+! ,--- !"#$%&'()*+,-+#'"(./#0*/1(2-33/*04($(5&*0-$1(( Virtual synchronous generators: A survey and new perspectives 6#+*0&$(7*/8&9+9(:"(!&;0*&:-0+9(<#+*="(20/*$=+( “The question that has to be Hassan Bevrani a,b, ⇑ , Toshifumi Ise b , Yushi Miura b a Dept. of Electrical and Computer Eng., University of Kurdistan, PO Box 416, Sanandaj, Iran 0/(6;/1$0+9(7/>+*(2";0+%;(( b Dept. of Electrical, Electronic and Information Eng., Osaka University, Osaka, Japan examined is: how much power !""" #$%&'%(#!)&' )& *)+"$ ','#"-'. /)01 23. &)1 2. -%, 2456 ?$-0@&+*(!+1&11+A( !"#$"%&'())) A(B*-#/()*$#C/&;A( *"+,-%'!"#$"%&'())) A($#9(?&11+;(D$1$*$#=+( electronics can the grid cope !789:;< "=>?<:;@7 (@7:9@? ':9<:8AB C@9 !"#$%&#'$%()*+'",'"%-#,.%/#",012%3#*',#4% /'(DE/F( #9<7G=;GG;@7 'BG:8=G with?” (European Commission) 5,)"16'% H;8I8; JK>. (<=LI8?? F1 M@@:K. N9<;7 *1 %O<=. %7O98P H1 $@GQ@8. <7O (K9;G N1 M9;AK: 7898:%+1*%;'<'*=''4> ? %@%58;8A8%$'%A11* ? @% !"#$%&'("()"&*'+,,, @%98%/1"'21 B %1*$%38%/#<<4.'" C @% !"#$%&'("()"&'+,,, % current controls what else? M d dt ω ( t ) = P generation ( t ) − P demand ( t ) . . . essentially D-control ⇒ plug’n’play (decentralized & passive), grid-friendly, user-friendly, . . . ⇒ today: where to do it? how to do it properly? all options are on the table and keep us busy . . . 9 / 32 10 / 32 Outline Introduction Novel Virtual Inertia Emulation Strategy inertia emulation Optimal Placement of Virtual Inertia Conclusions

Challenges in power converter implementations Averaged inverter model Real Time Simulation of a Power System with i αβ R L Contents lists available at ScienceDirect DC cap & AC filter equations: VSG Hardware in the Loop Electrical Power and Energy Systems i x i c v dc = − G dc v dc + i dc − 1 + + + journal homepage: www.elsevier.com/locate/ijepes Vasileios Karapanos, Sjoerd de Haan, Member , IEEE , Kasper Zwetsloot 2 m ⊤ i αβ Faculty of Electrical Engineering, Mathematics and Computer Science C dc ˙ Delft University of Technology Delft, the Netherlands Virtual synchronous generators: A survey and new perspectives v αβ i dc v dc g dc v x i load E-mails: vkarapanos@gmail.com, v.karapanos@tudelft.nl, s.w.h.dehaan@tudelft.nl C dc C Hassan Bevrani a,b, ⇑ , Toshifumi Ise b , Yushi Miura b C ˙ v αβ = − i load + i αβ To better study and witness the effects of virtual inertia, the a Dept. of Electrical and Computer Eng., University of Kurdistan, PO Box 416, Sanandaj, Iran Abstract- The method to investigate the interaction between a hardware of a real VSG should be tested within a power b Dept. of Electrical, Electronic and Information Eng., Osaka University, Osaka, Japan Virtual Synchronous Generator (VSG) and a power system is system. Investigating the interaction between a real VSG and − − − i αβ = − Ri αβ + 1 presented here. A VSG is a power-electronics based device that a power system is not easy as a power system cannot be L ˙ 2 mv dc − v αβ 1 delays in measurement acquisition, signal processing, & actuation modulation: i x = 1 2 m ⊤ i αβ , v x = 1 passive: ( i dc , i load ) → ( v dc , v αβ ) 2 mv dc 2 accuracy in AC measurements (need averaging) θ 3 constraints on currents, voltages, power, etc. model of a ˙ θ = ω � − sin( θ ) � synchronous ω = − D ω + τ m + i ⊤ M ˙ αβ L m i f 4 guarantees on stability and robustness cos( θ ) generator i f C ˙ v αβ = − G load v αβ + i αβ � − sin( θ ) � L s ˙ i αβ = − Ri αβ − v αβ − ω L m i f cos( θ ) today: use DC measurement, exploit analog storage, & passive control �������������������������������������� ���� 11 / 32 12 / 32 A standard power electronics control would continue by See the similarities & the differences ? i αβ R L DC cap & AC filter equations: 1 acquiring & processing i x 3 2 i c v dc = − G dc v dc + i dc − 1 reference synthesis + + + 2 m ⊤ i αβ tracking control of AC measurements C dc ˙ (virtual sync gen, (cascaded PIs) v αβ i dc v dc g dc v x i load C dc C droop/inertia, etc.) - C ˙ v αβ = − i load + i αβ 2 synthesis of references − − − i αβ = − Ri αβ + 1 L ˙ 2 mv dc − v αβ (voltage/current/power) 3 track references at 1 4 4 modulation: i x = 1 2 m ⊤ i αβ , v x = 1 i αβ R L passive: ( i dc , i load ) → ( v dc , v αβ ) 2 mv dc converter terminals i x i c + + + g dc v αβ i dc v dc C dc v x C i load 4 actuation via emulation θ − − − (inner loop) and/or via model of a ˙ θ = ω � − sin( θ ) � DC source (outer loop) synchronous ω = − D ω + τ m + i ⊤ M ˙ αβ L m i f cos( θ ) generator i f C ˙ v αβ = − G load v αβ + i αβ � − sin( θ ) � L s ˙ i αβ = − Ri αβ − v αβ − ω L m i f let’s do something different (smarter?) today . . . cos( θ ) 13 / 32 14 / 32