Development of dry-type transformers

Since AEG, a German company, developed the first 400kVA/20kV epoxy cast dry-type transformer in 1964, dry-type transformers have entered a stage of great development. At the same time, the United States also discovered Nomex insulation paper, which can be used as insulation material for H-class dry-type transformers. Therefore, there are currently two types of dry-type transformers: epoxy type and Nomex paper type.
Currently, in developed countries such as the United States, Germany, and Japan, the production of dry-type transformers accounts for over 20% of the total production of distribution transformers. In complete substations, dry-type transformers have accounted for 80-90%.
The report "Market Demand Forecast and Investment Strategy Planning Analysis of China's Dry type Transformer Industry from 2013 to 2017" shows that China has become the country with the largest production and sales volume of dry type transformers in the world. At present, various high and low voltage electrical products from abroad occupy some important markets in China, but dry-type transformers have hardly been imported from abroad since the end of the 20th century. In key projects and major projects in China, it is difficult to find traces of dry-type transformers from abroad. Under the current organizational structure of China's transmission network, the proportion of 10kV dry-type transformers is increasing year by year.
Currently, the pace of urban and rural power grid construction is accelerating, and China's power generation and consumption are increasing day by day. Generally speaking, for every 1 kW increase in power generation, an additional 11 kVA of transformer total capacity is required; And among them, Satons distribution transformers account for about 1/3-1/2 of the total transformer capacity. It is estimated that dry-type distribution transformers account for about 1/5-1/4 of all distribution transformers. Driven by investment in power grid construction, the transformer industry has a high level of prosperity, and production will maintain a growth rate of around 20% after 2010. Based on historical experience and changes in transformer voltage level structure, the proportion of distribution transformers is around 40%. Calculated at a 40% ratio, China's newly added dry-type transformer production will reach about 200 million KVA.
In China, in 1966, Shenyang Transformer Factory successfully developed ZSG-1800/10 air-cooled H-class dry-type transformer, Shanghai Transformer Factory successfully developed SG3-800/10/1.2/0.4 three coil self cooling H-class dry-type transformer, and in the late 1970s, Shanghai Transformer Factory independently designed and developed SCL-630 epoxy cast transformer. [4] In the past 20 years, with the development of the world economy, dry-type transformers have achieved rapid development worldwide, especially in distribution transformers. The proportion of dry-type transformers is increasing. According to statistics, in developed countries such as Europe and America, it has accounted for 40-50% of distribution transformers. In our country, it accounts for about 50%. In terms of production, since the second urban power grid renovation conference in 1989, the output of dry-type transformers in China has significantly increased. Since the 1990s, it has been increasing at a rate of about 20% per year. In 1999, the total output approached 10000 MVA (which greatly exceeded the predicted 4500 MVA 10 years ago), while in 2002, the total output reached 20000 MVA, and in 2004, it had reached 32000 MVA. This kind of growth rate is also unprecedented in the world.
From the above data, it can be seen that China has become one of the countries with the largest sales volume of dry-type transformation in the world, and is at the forefront of the world in terms of factory scale, product capacity, voltage, and other aspects.