Gunnar Asplund HVDC R&D Manager Sweden Latest HVDC Light developments IEEE Montreal 2006-06-21
HVDC Light, continuous reactive power control HVDC static Q (p.u.) HVDC dynamic HVDC Light P (pu) BA PTPS - 2 - Instantaneous control of active and reactive power over a wide area
Comparison HVDC-Classic und HVDC-Light Technology Convertor HVDC-Classic Current Source Converter Thyristor valve, grid commutation HVDC-Light Voltage Source Converter (VSC) Transistor valve (IGBT), self commutation Between stations Reactive support AC network requirement Overhead line Oil impregnated cable (mainly sea cable) By switched capacitor or filter banks Short circuit ratio > 2 Telecommunication Needed for start and operation Not needed. Extruded cable for both land and sea By the converter independent of the active power No requirement. Can start black network. BA PTPS - 3 - Power reversal Polarity has to be changed No polarity change Multiterminal operation Dimensions Valve hall and outdoor ac- yard Compact valve arrangement. Low profile and indoor ac and dc- yard Applications Complex Bulk power transfer, back to back, interconnection of asynchronous networks Simple Wind farms at sea, oil platforms, reinforcement of ac- systems, back to back between weak systems
The cable is the key for HVDC Light Cables from ABB 1350 km installed HVDC Light cables since 1998 745 km installed XLPE cables above 220 kv since 1978 out of totally about 4000 km installed world-wide BA PTPS - 4 -
HVDC Light Cable Development 2000 Directlink, 390 km 630 mm 2 Al conductor +/- 80 kv, 60 MW 1997 Hellsjön Prototype cable 95 mm 2 Al conductor +/- 10 kv, 3 MW 2001 Murraylink, 360 km 1400 mm 2 Al conductor +/- 150 kv, 220 MW 2006 Southern Link 1600 mm 2 Al conductor +/- 300 kv, 700 MW BA PTPS - 5 -
Cable laying Fiber Optic Cable HVDC Light Cable BA PTPS - 6 -
HVDC Light, transfer capability Power capability of ac and dc cables 700 600 +/- 300 kv DC cable BA PTPS - 7 - Power in MW 500 400 300 200 100 0 0 40 80 120 160 200 240 280 320 Distance in km 360 400 440 480 HVDC Light has no limitation in distance 400 kv AC cable compensated in one end 400 kv AC cable compensated in each end
HVDC Light,Matrix DC Voltage 500 A 1000 A 1500 A +/- 80 kv M1-95 MVA M2-190 MVA M3-285 MVA +-150 kv M4-178 MVA M5-356 MVA M6-535 MVA +/- 300 kv M7-356 MVA M8-713 MVA M9-1070 MVA BA PTPS - 8 - Avaliable 2006
Estlink 350 MW, +/- 150 kv, 75 km sea cable, 25 km land cable Finland Espo june 14 Estonia BA PTPS - 9 -
HVDC Light layout for 300 kv BA PTPS - 10 -
The southern link HVDC Light +/- 300 kv 700 MW BA PTPS - 11 -
AC line emulation BA PTPS - 12 -
N-1 criteria The ac- system should not be loaded more than it can safely withstand the loss of any line or generator Comment: This means that an HVDC Light transmission inside an ac network should have the same capability as an ac line BA PTPS - 13 -
Voltage stability of one remaining ac- line Voltage versus power 4.10 5 Voltage in kv 2.10 5 Maximum power Voltage collaps BA PTPS - 14-0 0 200 400 600 800 1000 Power in MW Without compensation
150 160 170 180 100 130 140 110 120 90 80 1,2 1 0,8 0,6 0,4 0,2 0 Dynamic stability Equal area Area1 delta1 delta0 Area2 delta2 0 10 20 30 40 50 60 70 BA PTPS - 15 -
AC line 400 kv ac line capability 1.2. 10 9 Potential additional power 1. 10 9 Powwer in MW 8.10 8 6. 10 8 4. 10 8 BA PTPS - 16-2.10 8 0 0 100 200 300 400 500 600 Distance in km Dynamic stability Max power Voltage stability Thermal limit.
32 30 28 26 24 22 20 18 16 Damping power needed in the HVDC Light Inertia 4 s Protection time 100 ms. 2 4 6 8 10 Number of lines BA PTPS - 17 - Percent of ac- line power
HVDC Light compared to an ac- line Distance = 400 Nlines = 2 1200 1000 Power in MVA 800 600 400 BA PTPS - 18-200 0 0 100 200 300 400 500 600 700 Active converter power in MW Total converter power Active converter power Reactove converter power Power in one ac line
Off shore BA PTPS - 19 -
Valhall 78 MW, 292 km cable The existing Valhall complex. HVDC module BA PTPS - 20 -
Troll A, converters on the platform The converters are housed in a prefabricated module, shipped and lifted onto the platform. BA PTPS - 21 -
HVDC Light for wind BA PTPS - 22 -
10 Multiterminal BA PTPS - 23 -
HVDC Light- multi terminal Several ac- nets are connected via one dc- net BA PTPS - 24 -
BA PTPS - 25 -