Design method of high tension coil of dry on-load coarse and fine voltage regulation transformer

The invention relates to a design method of a high tension coil of a dry on-load coarse and fine voltage regulation transformer, at least comprising normal turn number zones (1, 4) of a high tension coil and an air passage (5). The invention is characterized in that a coarse tuning turn number zone (2) and a fine tuning turn number zone (3) are connected in series between the normal turn number zones (1, 4), and the coarse tuning turn number zone (2) and the fine tuning turn number zone (3) are in forward direction serial connection structure. The coil has strong practicality and high reliability. The method adjusts voltage within a larger range in the mode of combining coarse tuning with the fine tuning.