At present, China's large-scale production of power companies are mainly divided into three types: assembly enterprises, Sino-foreign joint ventures and independent research and development enterprises. The imported components of the assembly enterprise are assembled domestically and sold directly to foreign markets. The quality of the products is good and the cost is high, but the adaptability to the domestic market is poor. The Sino-foreign joint ventures use more advanced foreign technology, and their products are available in the domestic market. High reputation; independent research and development enterprises can produce advanced series of power products, which can not only meet the needs of various electronic equipment, but also widely used in aerospace, new energy and other fields.

Based on the needs of the development of the reality, the future development trend of China's power supply (including electronic transformers) industry mainly shows the following four characteristics:

Energy saving and environmental protection

Energy conversion efficiency is an important indicator of energy conservation, that is, the ratio of output to input power. The higher the conversion efficiency, the less energy loss. Improving the conversion efficiency of the power supply requires improving the power factor by controlling the energy efficiency in different modes such as standby, hibernation, and idle. Reducing the power supply not only saves energy, but also lowers the temperature, thus extending the service life of the power supply and the whole product.

high efficiency

The traditional PWM switching power supply consumes a lot of power and does not reach the high frequency and high efficiency expected benefits. The power supply in the professional field greatly improves the working efficiency of the power supply through zero voltage conduction and zero current shutdown.

High reliability

The professional field power supply and electronic transformers extend the service life of the power supply from the selection of components and product plans. At the same time, by reducing the temperature rise, reducing the electrical stress of the device, reducing the operating current and other measures, the reliability of the power supply product can also be improved.

low noise

Ordinary switching power supplies simply pursue high frequency, and the noise also increases. The professional field power supply uses resonant switching loop technology to achieve both high frequency and low noise. However, the resonant conversion technology has high technical requirements and requires accurate control of the switching frequency.

“In the past, people’s focus was on the success of UHV. Now, when we have built and successfully run the 'two straight and one cross” UHV demonstration project, people are beginning to pay attention to what role UHV can play.” Recently, At the 3rd China Power Development and Technology Innovation Academician Forum, Huang Qili, an academician of the Chinese Academy of Engineering and honorary chief engineer of the Northeast Branch of the State Grid Corporation, made the above speech.

UHV power grid has four practical significance. The UHV project first brought about the optimal allocation of energy resources, which is no doubt. The energy enrichment in the western part of China is a reasonable way to transport energy from the place where the energy is concentrated to the place where the load is concentrated. It is necessary to use UHV technology to realize large-scale long-distance transmission; the second is to use the UHV grid as the backbone of the third generation. The power grid has been considered from the beginning of design to accept the connection of renewable energy, which is the practical significance of UHV to promote the development of clean energy; the third practical significance is the need for equipment manufacturing and UHV technology to upgrade simultaneously, which promotes The progress of the domestic equipment manufacturing industry; the fourth practical significance is to build a large channel for intercontinental energy transmission. "For example, the Sahara has abundant and developable solar resources, but it is sparsely populated, so much energy can not be consumed, and it can only be wasted. Now, with UHV, the energy of the Sahara can be transported to Available areas to address human energy use challenges."

China's energy resources and productivity are reversely distributed. The energy structure is dominated by coal, energy development is accelerated to the west and north, and large-scale and intensive development of wind power and solar power generation determines the importance of optimizing energy allocation and accelerating the development of UHV. The necessity. Wind energy and solar energy are natural and inexhaustible clean renewable energy sources. Common sense of life tells us that the wind has slow disease, sunny weather, wind energy, solar energy and other clean energy power generation has the characteristics of volatility and intermittent. The access capacity is not only limited by the size of the power grid, but also needs to use the pumped storage power station. The multiple functions and flexibility compensate for the randomness and non-uniformity of wind and solar power generation. All of these, UHV transmission is economical and has many benefits.

The completed UHV DC project, the Jinsut high-voltage DC project and the Xiluodu-Zhexi UHV DC project under construction, the Haminan-Zhengzhou UHV DC project, etc., have proved the rationality of the UHV DC transmission mode. And economic. It can be seen that accelerating the development of UHV and realizing "powering coal, electricity instead of oil and electricity from afar" is an inevitable choice for solving China's energy problems. This move not only promotes the construction of UHV cross-regional channels, but also optimizes coal-fired power grid layout. And solve the problem of cleaning power supply.