1. Frankfurt (Germany), 6-9 June 2011 HOW THE CUSTOMERS PERCEIVE THE PROBLEM OF VOLTAGE QUALITY Martin KAŠPÍREK martin.kaspirek@eon.cz David MEZERA david.mezera@eon.cz E.ON Czech Republic – Czech Republic

2. Frankfurt (Germany), 6-9 June 2011 This investigation was done on basis of:  3 years evaluation of complaints on VQ  Evaluated over 1.500 complaints on VQ  Sum of LV customer is 1.5 million  Real LV customers connected in different PCC The sources of this survey

3. Frankfurt (Germany), 6-9 June 2011 Progress of complaints

4. Frankfurt (Germany), 6-9 June 2011 What is the reason of this trend?  Worse VQ in LV networks, not in 2007-2010  Higher requirement of the customers Higher price for electricity New electrical appliances in households

5. Frankfurt (Germany), 6-9 June 2011 The correlation between price for electricity distribution and number of complaints * price is only distribution fee

6. Frankfurt (Germany), 6-9 June 2011 Structure of compliances according to the topic cause of complaints% of complaints voltage fluctuation3232 overvoltage15 voltage sags13 supply interruption13 voltage quality11 low voltage10 other6 total100%

7. Frankfurt (Germany), 6-9 June 2011 Evaluation of all complaints according to EN 50160 Ed. 2

8. Frankfurt (Germany), 6-9 June 2011 Evaluation of all complaints according to EN 50160 Ed. 2

9. Frankfurt (Germany), 6-9 June 2011 Evaluation of all complaints according to the type of feeder

10. Frankfurt (Germany), 6-9 June 2011 Conclusion  The amount of complaints till 2010 is caused by higher expectations of customers motivated by higher prices  The propability of not conforming VQ is 31%  The propability of not conforming VQ in overhead lines is 51%  The highest probability of not conforming VQ is in case voltage fluctuation. Mostly observed impact of VQ  Voltage variations – cause of 25% complaints, 14% of this complaints are justified. 25%x14%x0.01=3.5% of complaining customers have really problem with voltage variations