Power quality standard and voltage quality problems in Lithuanian distribution network

Influence of electric quality to proper work of the electric devices is very big. According to the requirements of quality, new Lithuanian power quality standard LST EN 50160 was accepted in 2001. Theretofore in Lithuanian was used old Soviet Union standard GammaOCT 13109-87. In the standard LST EN 50160 norms of total harmonic distortion were changed, more detail description of separate harmonic level was made. But after measurements level of harmonic in the various parts of network was find, that in some causes difficult to estimate quality of electric energy according the standard. These examples are described in this research.