1. P1 All rights reserved by SGCC 1 State Grid Corporation of China Jan.2009 India Innovations in the engineering of ±800kV UHVDC in China

2. P2 All rights reserved by SGCC 2 1. Project introduction 2. Technical features and innovations 3. Conclusion

3. P3 All rights reserved by SGCC 3 工程示意图

4. P4 All rights reserved by SGCC 4 Construction site of converter station Transmission line construction

5. P5 All rights reserved by SGCC 5 Typetest of the 800kV and 600kV upper transformer were passed in Nov.2008 and Jan. 2009 respectively.

6. P6 All rights reserved by SGCC 6 Typetest of the 6’’ thyristor was passed.Manufacture of valve module and test of the valve is ongoing. Test of 800kV/4000A smoothing reactor was passed. Bypass CB Disconnector RI capacitor DC Divider Composite support insulator DC yard equipment are successfully manufactured and energised for one year.

7. P7 All rights reserved by SGCC 7 According to the national regulation, the audible noise limitation at the boundary of station is: Daytime not exceed 60dB(A) ， Night time 50dB(A) 1. Movable BOX-IN for the converter transformer; 1 ． Sound damping of the converter station

8. P8 All rights reserved by SGCC 8 2. Layout:Face to face arrangement for the HV and LV valve hall, back to back for the two LV valve halls and AC filter grid type arrangement is well designed to damp noise and save land as much as possible. 3. Sound-proof screen along part of the station boundary 4. Smoothing reactor: Sound-proof cap, sound absorb design

9. P9 All rights reserved by SGCC 9 2 ． Study on Ieq limitation Soil resistivity Ieq limitation 200  ·m 3000 mA≤Ieq≤6000 mA 600  m 2000 mA≤Ieq≤4000 mA 1000  m 1500 mA≤Ieq≤3000 mA

10. P10 All rights reserved by SGCC 10 Electrode at the sending side was designed to be shared by two to three HVDC converter which is quite close to each other. Block of same polarity of 2 different HVDC links are considered. Max.allowable step voltage was carefully studied to optimize the electrode design. ３． Common electrode at the sending side

11. P11 All rights reserved by SGCC 11 The scheme of de-icing is to boost the current in the transmission line by altering the connection status between converter units through the ON/OFF status of related switches added in the DC switchyard. 4 ． De-icing configuration

12. P12 All rights reserved by SGCC 12 Conclusion ： 1.For a safe, economic UHVDC project, a series of innovative and optimized design different from conventional HVDC links have been applied in Xiangjiaba-Shanghai project which is under construction. 2.Those new features will be of good reference for future HVDC projects.

13. P13 Thank you