APPENDIX-A HVDC MILE STONE 1954:First HVDV Project Gotland 1 in Sweden. 1965:Mercury-arc valveprojectcommissioned:konti-kan(250mw),sakuma (300MW) (image) and NewZealand (600 MW).Development starts on HVDC valve based on thyristors. 1970: ABB's last mercury-arc valve project commissioned Pacific Intertie (1,440MW, ±400 kv), USA. 1975:The world's first HVDC transmission project with 12-pulse converters: pole1 of the Skagerrak link, 500 MW, Norway Denmark, commissioned. 1979: Contract signed for the world's largest HVDC transmission: Itaipu, Brazil,6,300 MW, ± 600 kv. 1982:The world's first project with 500 kv thyristor valves: Inga-Shaba, Congo, transmission (560 MW) commissioned.(also the world s longest line 1,700 km.) 1985: Itaipu bipole 1 (3,150 MW, ±600 kv) commissioned. The 200 MW High gate back-to-back station commissioned after a record short delivery time of 17 months. 1987: Itaipu bipole 2 (3,150 MW, ±600 kv) commissioned. 1989: New world record for HVDC submarine cables: 400 kv, 500 MW, 200 km for Fenno-Skan.
1992:The first multi-terminal HVDC transmission, Quebec New England (2,000 MW, ± 500 kv) commissioned. 1994:New world record for HVDC submarine cables: 450 kv, 600 MW, 250 km for Baltic Cable, Sweden -Germany. 1999:The world's first commercial HVDC Light (50 MW) project commissioned in Gotland, Sweden. 2000:The world's first HVDC project with CCC commissioned at Garabi, Brazil, 2x550 MW back-toback. 2002: The world's largest HVDC converter,1,500 MW, 500 kv, commissioned in pole 1 of the Three Gorges Changzhou transmission, China.The world's longest land cable, the Murraylink HVDC Light transmission (220 MW, 180 km) commissioned in Australia. 2005: Commissioning of the world's first offshore platform HVDC transmission: Troll HVDC Light (2 x 42 MW), Norway. 2006: Commissioning of the world's largest Voltage Source Converter HVDC transmission, Estlink, 350 MW.
APPENDIX B CIGRE HVDC Benchmark System data Parameters Rectifier Inverter AC Voltage Base 345kV 230kV Base MVA 100MVA 100MVA Transformer Tap( HV side) 1.01pu 0.989pu Voltage Source 1.088 angle 22.18 0.935 angle -23.14 Nominal DC Voltage 500kV 500kV Nominal DC Current 2kA 2kA Transformer leakage reactance Source impedance 0.18pu R=3.737 ohm L=0H 0.18pu R=0.7406ohm L=0.0365 H System frequency 50Hz 50Hz Minimum Angle α = 15 γ =15 Transformer sizing Inverter transformer DC power to be delivered Pdi = 1000MW DC Voltage level Vdi = 500kV DC rated current Idi = 1000/500 =2kA
Rectifier firing angle α = 15 Minimum Extinction angle γ = 15 RMS value of secondary line current (Valve side) ILLi = 2/3(Idi) =1.633kA Let Line voltage (valve side) of inverter transformer = VLLI MVA of each Transformer STi = 3 ILLi VLLI Therefore, STi = 2.82844 VLLi Base impedance Zbase = VLLI 2 / STi = 0.35355 VLLi Transformer leakage reactance XLi = 0.18pu = 0.18 * Zbase= 0.06364 VLLi No.of Bridges N=2 But Line voltage for each bridge Vdi/2 = 1.35 VLLi cosγ - 3 Idi XLi/π After substituting the data VLLi =215.0753kV Rating of the inverter transformer = 608.3248MVA Turns ratio Y/ Transformer K = 230/ 3/215.0753 = 0.617 Y/Y Transformer K = 230/ 3/215.0753/ 3 = 1.069 Rectifier Transformer Cable Resistance Rcab = 5Ω Voltage drop Vdrop = Idci *Rcab =10kV Cable loss, Pcable = 20MW DC power to be delivered Pdcr = Pdci + Pcable = 520MW DC Voltage level Vdcr = Vdci + Vdrop = 510kV DC Rated current Idcr = Pdcr/Vdcr =2kA
Rectifier Firing angle α = 15 RMS Value of secondary line current (Valve side) ILLr = 2/3(Idr) =1.633kA Let Line voltage (valve side) of rectiifer transformer = VLLr MVA of each Transformer STr = 3 ILLr VLLr Therefore, STr = 2.82844 VLLr Base impedance Zbaser = VLLI 2 / STr = 0.35355 VLLr Transformer leakage reactance XLi = 0.18pu = 0.18 * Zbaser= 0.06364 VLLr No.of Bridges N=2 But Line voltage for each bridge Vdr/2 = 1.35 VLLr cos α - 3 Idr XLr/π After substituting the data VLLr =215.6526kV Rating of the inverter transformer = 609.9578MVA Turns ratio Y/ Transformer K = 345/ 3/215.6526 = 0.924 Y/Y Transformer K = 345/ 3/215.6526/ 3 = 1.599
APPENDIX C Complete System data for Chapter-4
APPENDIX D Technical data for 800MW CCC-Application Vdbase = 500kV Idbase =1.6kA Vlphase =300kV Vlbase =364kV Rated DC Voltage at the converter Rated DC Current at the converter Rated primary side AC line Voltage Rated secondary side AC line Voltage SCR =1.82-75 Short Circuit ratio Zs = Impedance in System Equivalent TMVA =850MVA L=74.42mH Transformer MVA rating Transformer leakage inductance as seen from valve / secondary side where Lpu = 0.15pu C=48 Series capacitance of CCC system =314.1593rad/s Angular frequency of the AC source Angular frequency Qf=440Mvar Bf=Qf/ Vlbase 2 Gf=0 Reactive Power Produced in the AC filter Filter susceptance Filter Conductance
Technical data for 1000MW CCC -Application Vdbase = 500kV Idbase =2.0kA Vlphase =230kV Vlbase =211.42kV Rated DC Voltage at the converter Rated DC Current at the converter Rated primary side AC line Voltage Rated secondary side AC line Voltage SCR =2.5-75 Short Circuit ratio Zs = Impedance in System Equivalent TMVA =1196MVA L=94mH Transformer MVA rating Transformer leakage inductance as seen from valve / secondary side where Lpu = 0.18pu C=100 Series capacitance of CCC system =314.1593rad/s Angular frequency of the AC source Angular frequency Qf=145Mvar Bf=Qf/ Vlbase 2 Gf=0 Reactive Power Produced in the AC filter Filter susceptance Filter Conductance