I. Overview

Distribution transformers in China usually refers to voltage of 35kV and 10kV and below, the following capacity 6300kVA power directly to end users of power transformers. At present the total line power distribution transformers operating loss of about 41.1 billion kWh, accounting for 2000 of 3.16% of total generating capacity. Although the distribution transformer is a high-efficiency equipment (95-99%), but because of its huge number of fixity and no-load power, transformer efficiency even with minor improvements can be considerable energy savings and reduce greenhouse gas emissions, so its own there is a huge energy saving potential.

The late 1990s, China's fast development of distribution transformer industry. Since 1997, due to the pull of urban and rural power grid renovation project, the power transformer industry maintained a good momentum of development. Power transformer output growth in 1999 24.81%. Output growth in 2000 15.88% power transformers, distribution transformers to increase the proportion of the number: the number of distribution transformers in 1999 rose from 34.72% in 1998 rose to 39.51%, an increase of 5 percentage points; the number of distribution transformers in 2000 accounted for 36.89%. (10kV6, 300KVA transformer output was 304,099 and the following units, 41,778 KVA, 35kV6, 300KVA transformer production and below 7,821 units, 9316.4KVA). Urban and rural power grid renovation project in selected oil-immersed distribution transformer equipment have all been achieved by the S7 to S9 type of change model.

With the development of market economy and technological advances, new materials, the continuous application of new technology, new low-loss distribution transformers have been developed. Many domestic Transformer Manufacturer invested heavily in the introduction of foreign advanced manufacturing technology and equipment, and constantly developed and various structural forms of low-loss transformer transformer, transformer oil has emerged as the new S9 series of more energy efficient than the S10, S11 series, New dry-type transformers SC9 series and amorphous alloy core products such as low loss distribution transformers in China have shown potential for energy savings.

In addition, the online operation of distribution transformers over 20 years of military age in the low efficiency of about 10% of old transformers, estimated capacity of about 240 million kVA, these transformers in accordance with the sixties and seventies standard design products, loss is very high, if it took a certain investment to replace the old transformer with S9 will certainly be a great economic benefits. Calculated according to different capacity, the purchase of  Variable Transformer to replace the old transformer S9 return on investment was generally only 2 to 3 years (excluding the old transformer cost recovery charges and disassembly conditions), its energy-saving potential.

II. Transformer trends and product features

Distribution transformer industry through our continuous efforts in the future than in the past 90 years have seen a breakthrough, silicon steel transformer core material is not only a performance improvement, but also in the capacity of the structure and manufacturing process the breakthrough, thus saving energy reduce the load current and noise have made great progress.