1. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 One phase rural distribution installation with direct connection to HV trunk line P.A. MONFILS, Jean-Louis LILIEN, A. OMBOUA

2. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 2 Scope of the project Local conditions Makola application Load Reliability aspects SUMMARY

3. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 3 Scope of the project The problemThe solution

4. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 4 Typical low load user (Makola)

5. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 5 One 500 people village: Estimated load (UNESCO) Typical low load user (Makola)

6. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 6 Local conditions

7. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 7 Local conditions 846 km from the main power supply Very low short-circuit level: 360 A Very low load: –Frequent over-voltages –Important power availability (50 kVA = 3.10 -4 SIL) Very high keraunic level (lightning activity)

8. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 8 Local conditions High soil resistivity: > 3000 .m –HV earth resistance: 35  –Risks for the inhabitants in case of line-to-earth fault in case of lightning on the HV line –Needs deep analysis of earthing system

9. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 9 Schematic diagram Makola application

10. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 10 SF6 VT technology: high reliability Limited maintenance Limited weight: easy to transport/handle Limited cost (no switch bay) Direct from 245 kV to 230 V (50 kVA) Makola application

11. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 11 Makola application

12. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 12 Makola application

13. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 13 Makola application

14. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 14 Load recording

15. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 15 Load recording

16. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 16 Reliability aspects Improved technology (SF6 VT) with very limited maintenance Immediate protection by ZnO surge arrester One year experiment: the reliability of the equipment is much higher than the HV system (min 5 power outages per month) Possible improvement by use of HV fuses

17. MONFILS Pierre-André (BE) Barcelona 12-15 May 2003 17 Improvement of the quality of life of rural populations (< 3% of peoples access electrical power in Congo) Electrical energy gives access to drinking water, food preservation, lighting. Electrical energy may help starting development of local activities Our solution is cost effective, easy to handle and reliable Conclusions