摘要：A significant increase in the distributed generating sources connected and planned for connection to medium voltage (MV) grids makes voltage criteria very important in assessing the sources’ connectivity.Many requests have been submitted for connection of distributed generation sources at a considerable distance (even a dozen or so kilometres) from a main supply substation’s MV buses.As a rule,these are requests for the interconnection deep in an existing MV bus, but also directly to MV switching substation bays.Then maintaining appropriate voltage levels becomes a basic technical problem.Another technical problem relates to meeting the power quality criteria.THD index,and the level of individual harmonics,significantly increases,in many cases reaching or even exceeding the boundary values.With their extensive experience,the authors present examples and results of some analyses herewith.They indicate the impact of voltage conditions on the connection possibilities of distributed generation to MV grids.
关键词：distributed generation in medium voltage grid;connectivity voltage criteria
