Wirewound types still dominate power transformers production

Traditional and emerging applications keep the mature category strong. Some companies sustain initiatives for planar and other advanced variants.

China makers of power transformers stay focused on conventional wirewound units, capitalizing on robust demand in household appliances, telecom products, computers, consumer and automotive electronics, LED devices and industrial equipment. They are also eyeing the type's burgeoning market in power converters and inverters used in solar and wind energy systems, power sources, on-board chargers, DC-DC converters and charging piles in electric vehicles, and power supplies in medical electronics.

There remain simultaneous efforts as well to keep the line up-to-date with the miniaturization trend. Although demand is still limited, a few companies have been pursuing the development of planar, chip and thin-film kinds in the past several years, with the first representing less than 10 percent of local output. The current planar selection consists of 5W to 20kW and 20kHz to 2MHz models with 98 percent typical efficiency, and low leakage inductance and EMI.

So far, only about 10 of China's 3,000-plus suppliers of power transformers can offer planar variants. These include Shenzhen Belta Electronics Corp. Ltd, Shenzhen Highlight and Shenzhen Boulder.

In the absence of significant technology improvements in the mainstream line, domestic manufacturers ensure products have high efficiency and low loss.

Local suppliers estimate about a 10 percent annual sales growth in the next few years, spurring manufacturers such as Dezhou Xinping Electronics Co. Ltd to increase production capacity.

China's power transformers account for nearly 30 percent of the global yield.

Makers there are based in the Pearl River and Yangtze River Delta regions and the Bohai Bay Rim Economic Region. Guangdong province is the key manufacturing hub, gathering about 50 percent of the companies responsible for 60 percent of local volume. The rest of the pool is spread over the provinces of Zhejiang, Jiangsu and Anhui, and Beijing and Shanghai.