Three Phase Transformer Winding

 The most commonly used in the power system is the three phase transformer winding. It is more economic, less area, more convenient for maintenance and management to use a 3 phase transformer winding to connect three power transmission systems of different voltages  than using two ordinary transformers. The three phase three winding transformer is often to use  the connection method of Y-Y-△, namely that both original and secondary winding use Y connection method, and the third winding uses △. △ method itself is a closed loop which permits third harmonic current of the same phase to pass, so that third harmonic current does not appear  in the original and secondary winding of the Y connect method. In that way, it also provides a neutral point for both the original and the secondary side. In the long distance transmission system, the third winding can also connect with a synchronous condenser to improve the power factor of line.

 

The capacity of the three phase transformer winding is the largest capacity among the three winding.

 

Multi-winding  transformers are often used in electronic equipment, such as power transformer. 1 and 1┡ are two same original winding.  They can be connected in series or in parallel to match two different supply voltages. 2、3、4、4┡ are secondary winding which can output different voltages to meet different needs. It can also guarantee the isolation requirement of each circuit.

 

Formula is as follows :

 

n13=N1/N3=E1/E3≈U1/U3

n23=N2/N3=E2/E3≈U2/U3

 

The capacity of three phase transformer winding is the largest capacity in the three winding.

 

Yuebian Electric Co.,Ltd, approved by ISO9001, is one of the largest power transformer suppliers in China. We provide step down transformer, power transformer, distribution transformer and etc. Want to know more? Please contact us.

Three Phase Transformer Connections

 Three Phase Transformer Connections  

In order to show the phase relation of the coils voltage on both sides , the connection mode of the three-phase transformer is divided into several groups which are called the connection group. Among the Three phase power transformer, the phase voltage ratio of the primary and secondary power transformers is fixed and equal to the ratio of the number of turns. According to the way that the coil is connected, it can be divided into twelve kinds of connection groups: 1--12 points.

 

The connection group of three-phase transformer is divided into 12 kinds, including 6 kinds of single arrays and 6 double arrays. When primary side coil and second side coil connects differently, it is a single array, including Y/Δ-1, 3, 5, 7, 9, 11. When primary side coil and the second side coil connection is consistent, such as Y-Y, Δ-Δ, it's a double array, including: Y/y-2,4,6,8,10,12. In China, the connections of Y shape to Y shape are 12 point wiring. The  connection of Y shape to Δ is 11 points wiring, except other special cases.

 

The groups of different transformers generally adopt the clock representation method. Because the phase difference between the line voltage corresponding to the one and two side of the transformer is integer multiples of 30 degrees. It coincides with the angle among the clock hours. The clockwise moves exactly 30 degrees an hour. Therefore, it can be a very vivid description of this problem with clock representation. In the method, use the primary side line voltage vector as the long hand of a clock and fix it on the 12 points. And then use the line voltage vector corresponding to the two side as the short hand of a clock, and take the point which is pointed by the short hand as the group number of wiring group.

 

Yuebian Electric Co.,Ltd, approved by ISO9001, is one of the largest three phase transformer suppliers and power distribution transformer manufacturers in China. We provide distribution transformer connections, step down transformer, power transformer, distribution transformer and etc. Want to know more? Please contact us.

 

The Difference between Dry Type Transformer and Oil Filled Transformer

 Of course, the same is true that the power transformer will have a core for the magnetic circuit and a winding for the circuit. The biggest difference is in "oil filled" and "dry". That is to say, the cooling medium of the two is different. The former uses transformer oil (and of course other oils such as beta oil) as the cooling and insulating medium, and the latter uses air or other gases such as SF6 as the cooling medium. Oil filled transformer is to place the body consisting of iron core and winding in a fuel tank filled with transformer oil. Dry type transformer often encloses the core and windings with epoxy resin. There is also a kind of non-encapsulated type that is used nowadays. The windings are impregnated with special insulating paper with special insulating paper to prevent the windings or core from getting wet. (Because the two are derived from different categories due to different methods of process, use, and structure, we are narrowly speaking.)

 

In terms of production and usage, the current dry type transformer’s voltage rating is only 35kV. The capacity is small compared to oil filled transformer, about 2500kVA. Moreover, since the dry type transformer manufacturing process is complicated and costly with respect to the oil filled transformer of the same voltage level and the same capacity, the oil filled transformer is still much more in terms of the amount of oil. However, due to the environmental protection of dry change, flame retardant, impact resistance and so on, it is often used in indoor and other high-demand power supply and distribution sites, such as hotels, office buildings, high-rise buildings and so on. If you are just a transformer user, it should be enough to understand this.

 

Dry type distribution transformer and oil filled transformers have their own advantages and disadvantages. Oil filled transformers are low in cost and easy to maintain, but they are flammable and explosive. Dry type transformers can be installed in the center of the load due to their good fire resistance to reduce voltage loss and power loss. However, dry type transformers are expensive, bulky, moisture-proof and dust-proof, and have high noise.

 

Oil filled transformers gradually withdrew from the market and dry type transformers were adopted. The dry type transformer can be disassembled, transported and drained, cleaned, easy to maintain, installed without a machine base, and without oil leakage pool.

 

The two are better distinguished from the outside.

The biggest difference between oil filled transformers and dry type transformers is whether there is "oil". Since the oil is liquid and has fluidity, the oil-immersed transformer must have a casing. Inside the casing is transformer oil, the oil is immersed in the coil of the transformer, and the coil of the transformer is not visible from the outside. The dry type transformer has no oil, so it does not need the outer casing, and the coil of the transformer can be directly seen. Another feature is that there is an oil pillow on the oil filled transformer, and the transformer oil is stored inside, but now the new oil filled transformer also has no oil pillow.

 

In order to facilitate heat dissipation, that is, for the convenience of the flow of internal insulating oil, a heat sink is designed outside the oil filled transformer, just like a heat sink. The dry type transformer does not have this radiator, and the heat is cooled by the fan below the transformer coil. The fan is a bit like an indoor unit for home air conditioning.

 

Due to the need for fire protection, oil filled transformers are typically installed indoors or outdoors in separate transformers. The dry type transformer is definitely installed indoors, and is usually installed in a low-voltage power distribution room and installed side by side with the low-voltage power distribution cabinet.

 

YueBian is one of

oil filled transformer manufacturers

. Welcome to buy our products.

 

Yuebian Electric Co.,Ltd, approved by ISO9001, is one of the largest dry type transformer manufacturer in China. We provide outdoor dry type transformer, step down transformer, oil transformer, distribution transformer and etc. Want to know more? Please contact us.

 

Structure and Performance Analysis of Three-phase Three-column Amorphous Alloy Dry Type Transformer

 Amorphous alloy dry type transformer is a new type of energy-saving transformer made of new magnetic conductive material (amorphous alloy). Compared with the transformer with silicon steel sheet as the core, the no-load loss is reduced by more than 70%, and the no-load current is reduced by about 80%. It is a distribution transformer with ideal energy saving effect, especially suitable for rural power grids and places with low load rates in developing regions.

 

Amorphous alloy materials and their dry-type transformer characteristics

The windings and clamping devices of amorphous alloy epoxy cast dry type transformers are basically the same as ordinary epoxy cast dry type transformers, but the core materials used are quite different. A new high-tech product called amorphous alloy was chosen. The amorphous alloy is a very thin magnetic material having a thickness of about 0.03 mm. It is a strip of sheet material cast from a certain proportion of alloy material using ultra-quenching technology (cooling rate 107/s) through a cooling float. Compared with cold-rolled silicon steel sheets, amorphous alloy materials have five advantages, but there are also five disadvantages. These shortcomings bring a lot of difficulties to the design and manufacture of the transformer.

 

The advantages of the five aspects are reflected in:

(1) It uses an isotropic soft magnetic material;

(2) The loss is very low, about 30% of the silicon steel sheet;

(3) The resistivity is about 3 times that of the silicon steel sheet;

(4) The subsequent process is convenient to process (the subsequent process can obtain the required magnetic properties);

(5) The manufacturing process is environmentally friendly.

 

The five disadvantages are:

(1) The thickness is very thin, the surface of the material is not flat, and the core filling factor is about 0.86;

(2) The hardness is much larger than that of silicon steel sheet, which brings inconvenience to cutting and processing;

(3) It must be annealed;

(4) The material is fragile after annealing;

(5) The influence of mechanical stress on its performance is very large.

 

Due to the formation of the amorphous alloy strip, the cross section of the core is generally rectangular and the windings are also rectangular. There is a break in one yoke, open the break set winding, and then close the break. The core adopts a new three-phase three-column structure. Due to the advantages of flame retardant, high reliability and maintenance-free, amorphous alloy dry type transformers have broad development prospects in the power distribution market.

 

YueBian Company has

dry type transformer for sale

. Welcome to buy.

 

Yuebian Electric Co.,Ltd, approved by ISO9001, is one of the largest distribution transformer manufacturers in China. We provide step down transformer, oil transformer, distribution transformer and etc. Want to know more? Please contact us.

Step Up Transformer Efficiency

 The step up transformer is a device that transforms low AC voltage, large current and small impedance into high AC voltage, small current and large impedance. When there is alternating current through the primary coil, the core (or magnetic core) will be generated in the AC flux, the secondary coil induces a voltage (or current). The input of the transformer must be the alternating current, and its output voltage is proportional to the number of turns of the output or input coil. If a battery is used because it is a DC, the switch circuit must be added to the input circuit to turn it into a changing voltage. In this way, the alternating high voltage power can be obtained at the output end.

 

Formula and description: the number of the winding of the two lines of transformer is N1 and N2, N1 is primary and N2 is secondary. An induction electromotive force is generated at both ends of the secondary coil by adding an AC voltage on the primary coil. When the N2 is greater than N1, its induced electromotive force is higher than the primary voltage, which is called the step up transformer.

 

Yuebian Electric Co.,Ltd, approved by ISO9001, is one of the largest oil filled transformer manufacturers in China. We provide step down transformer, oil transformer, distribution transformer and etc. Want to know more? Please contact us.