Product category: product center oil immersed transformer product description: win in stability, safe and reliable, life-long short circuit resistance; State control, life management; Energy saving, high temperature resistant process features: insulation, high temperature resistant hybrid insulation system.   In order to improve the longitudinal capacitance distribution of high voltage coil under impulse voltage, the medium and small capacity of high voltage coil are tangled continuous type, and the large capacity is inner screen continuous type; All the coils are guided oil circulation structure, which can reduce the temperature rise of the winding, and the design life of the product is 30 years. The fully automatic laminating robot is fully automatic laminating, which adopts a fully inclined 45 degree 7-step step seam structure. The iron core will be made of high permeability cold-rolled silicon steel sheet, with no hole binding, frame structure, D-shaped yoke structure as coil to replace large area platform and stepped joint. Swiss import automatic cutting lamination robot, ensure core burr 20um. The multistage joint of iron core reduces no-load loss, no-load current and noise level. There are two kinds of tank structure: bell type and barrel type. All seals are end limit seal; The fillet of metal parts inside and outside the box shall be debugged, and the weld and seal shall undergo three leakage tests (fluorescence, positive pressure and negative pressure); The paint is made according to the antirust requirements of household appliances. Performance features: traction transformer for electrified railway features: 1, secondary load short circuit trip frequently; 2. The transformer is often impacted by switching overvoltage; 3. The load is extremely unbalanced, sometimes the overload factor is high for a short time, and the time fork is longer for space-time load or light load; 4. The voltage fluctuation steepness is large, especially for the bus voltage of remote substation, the no-load voltage is high, over 29kv, the voltage drop is large under heavy load, less than 24kV: 5, single-phase load;   The requirements of the railway department for the use of traction transformer are as follows: 1. Safety and reliability: This is the most basic work goal of the railway department. Traction transformer is a key equipment in the whole electrified railway. If the power failure of the whole substation is caused by the quality problems of the transformer, it will cause huge losses to the transportation and production; 2. Low loss, energy saving advantages: can significantly reduce production costs; 3. Low loss, low temperature rise, strong overload capacity: improve capacity utilization, save cost; 4. The principle of "state control, life management" is achieved. Traction transformer type: 1, 110kV and 220kV single-phase traction transformer: for at power supply and direct supply; 2. Ll0kV and 220kV V / V wiring traction transformer: used for at power supply and direct supply; 3. 110kV and 220kV balanced traction transformer: for direct power supply; 4. Self coupling transformer: for at power supply; 220kV single-phase traction transformer: due to the large capacity of 22nkv power supply network, the harmonic and negative sequence components generated by 220kV single-phase traction transformer have little impact on 220kV power supply network: 220kV power supply system is more stable and reliable, single-phase power supply is more in line with the characteristics of railway power consumption, with simple protection and small investment, which can effectively reduce railway operation cost. With the development of China's economy and power system, 220kV single-phase traction power supply is an inevitable trend. The connection group of single-phase traction transformer is i-i. according to the capacity or user's requirements, the internal wiring can be series or parallel. V / V connection traction transformer: V / V connection transformer is one of the forms of railway traction transformer, which is the specific application of single-phase transformer in railway traction; This type of transformer has two structural forms. One is that two single-phase transformers are placed in the same oil tank, which is a three column structure. The coils of the two single-phase transformers are respectively sheathed on the side pillars of the two iron cores, and there is no coil on the middle pillar of the iron core, which only forms the circuit of magnetic flux; The other is the combination of two transformers, namely the four column structure; In these two structures, there are two single-phase transformers of equal capacity and unequal capacity.