Electronic transformer technology innovation to deal with the difficulties

The core loss of the electronic transformer is the main component of the standby loss. Therefore, all of them require clear and strict requirements on the efficiency or loss of the electronic transformer.

In recent years, the prices of core materials and conductive materials used in electronic transformers in power supplies have continued to rise, and upstream raw materials have formed a seller’s market. As a power supply user of downstream electronic transformers, they can select and purchase globally to form a buyer's market. In the middle of the electronic transformer industry, only take the road of technological innovation to get rid of this dilemma. However, in the mature electronic transformer industry, technological innovation is more difficult. However, the improvement of every small link can bring new ideas and new products.

To take the road of technological innovation, we must always remember the purpose to be achieved. The electronic transformer in the power supply, like any product that is a commodity, carries out any technological innovation, and must complete specific functions under specific conditions of use. The pursuit of performance is the best price. Today's power supply products are generally characterized by lightness, thinness, shortness, and smallness, and they are being developed toward miniaturization and portability. The electronic transformer must adapt to the volume and weight requirements of the user's power supply product. At the same time, the prices of raw materials (core materials and conductive materials) for electronic transformers have risen. Therefore, how to reduce the volume and weight and how to reduce the cost has become the main direction for the development of electronic transformers in recent years.

Silicon steel is an iron core material that is widely used in electronic transformers in industrial frequency power supplies. To reduce the amount of iron used in an electronic transformer, the working flux density (working magnetic density) of silicon steel must be increased. The working magnetic density of silicon steel is determined by both the saturation flux density and the loss. Because efficiency is an important performance indicator for electronic transformers, many power supply products now offer standby loss requirements in order to save energy. The core loss of the electronic transformer is the main component of the standby loss. Therefore, all of them require clear and strict requirements on the efficiency or loss of the electronic transformer.

Since last year, the prices of oriented and non-oriented cold-rolled silicon steels have risen. Compared with R-type, CD-type, and EI-type cores, winding-type toroidal cores can save more than 20% of core material costs and expand electronics due to less material consumption. The scope of use in the transformer. The wound-type toroidal core can give full play to the properties of oriented cold-rolled silicon steel, and its working magnetic flux density is much higher than that of non-oriented cold-rolled steel. At the same time, unlike the R, CD, and EI iron cores, silicon steel materials can be fully utilized with no corner scrap and a material utilization rate of more than 98%.

As a large class of power transformers for electronic transformers, cores with high magnetic core density can reduce the number of coil turns and reduce the amount of copper without reducing the core section and volume. In the present situation where the price of copper is much higher than that of iron core material, it may be a better design improvement plan.

Soft ferrite is a core material used in a large number of electronic transformers in high-frequency and high-frequency power supplies. Compared with metal soft magnetic materials, soft ferrite has low saturation magnetization, low magnetic permeability, and low Curie temperature. Several major weaknesses. In particular, the Curie temperature is low, the saturated magnetic density Bs and the unit volume power loss Pcv will change with temperature. As the temperature rises, Bs drops, Pcv begins to fall, and rises after reaching the trough. Therefore, under high temperature conditions, as long as Bs maintains a high level, the working magnetic density Bm can be selected to be higher, thereby reducing the number of turns of the coil and reducing the amount of copper used and the cost. High-temperature, high-saturation, magnetically-encapsulated ferrite materials can also extend the upper limit of the temperature used by electronic transformers to 120 or even 150 angstroms.