The dry-type transformer is composed of two winding resistances， Y & rdquo;， Y & rdquo;， & ldquo; y， D & rdquo; and & ldquo; D， D & rdquo;. In China， only & ldquo; y Y & rdquo; and & ldquo; y， D & rdquo; are selected. Because there are also two types of Y-connection with neutral line and without neutral line. If there is no neutral line， it will not be upgraded. All marks show that with neutral line it will not be upgraded The letter N after the English letter Y indicates that the neutral line has transformer grounding wire. Yn wiring group， when UAB and UAB overlap， the minute hand points to . & ldquo; & rdquo; in the new wiring group， it is indicated by & ldquo; & rdquo.
For no-load impulse closing of transformer， pay attention to the following matters:
AstaraWhen the output power P of the transformer is equivalent to the input power P， the efficiency & ETA; Equivalent， there is no such transformer. The electromagnetic energy of transformer always causes loss. The key of this kind of loss is copper loss and iron loss. Copper loss refers to the loss caused by the number of turns of transformer coil. When the current has a fever according to the number of turns of the coil， part of the electromagnetic energy changes into energy and is lost. Because the electromagnetic coil is generally wound by copper core wire with insulating layer， it is called copper loss.
How to reduce the failure of dry-type transformer?
VenezuelaThe long-term overload of power transformer will slowly cause the scalding and insulation aging of solenoid coil， resulting in short circuit between coils， two-color short circuit or short circuit on the ground， resulting in the ignition of power transformer. Therefore， and overload is not allowed in the whole process of operation.
Power transformers are also used for testing，AstaraDry type transformer model making， which are called test power transformers. They can be divided into inflatable， oil transformer， dry test and other test power transformers. They are the basic test equipment for communication AC compression test for many consumers such as power stations， power supply bureaus and scientific research institutions. According to the specifications of the Bureau of quality supervision， It is used to carry out insulation compressive strength test under required current for various electrical products， electrical components and insulating raw materials.
The project cost is different. Compared with the purchase price of capacity transformer， the purchase price of dry-type transformer is much higher than that of oil immersed transformer.
When the power transformer operates at full load， it needs a large reactive load. This reactive load shall be provided by the power supply and distribution system. If the transformer volume is too large， it will not only increase the initial project investment， but also make the transformer operate at full load or load for a long time， expand the proportion of full load loss， reduce power factor and increase Internet loss. Such operation is neither economic development nor scientific.
Transformer manufacturers said that at this stage， China"s energy-saving distribution transformer market is relatively scattered， coupled with the constraints of factors such as low threshold in the field， uneven companies， lack of evaluation and specifications， and inadequate technical innovation， resulting in slow marketing of energy-saving transformers.
Different diversion methods， dry-type transformers mostly use silica gel waterproof casing， while oil transformers mostly use porcelain waterproof casing;
reformPower transformer is an idealized supporting facility transformer for medium cabinet and high-voltage cabinet at the present stage，Astara10kV dry type power transformer， and can be equipped with safety protective casing according to different waterproof grades. It is applicable to key or unique natural environment sites such as multi-storey buildings， commerce， airports， tunnel construction， it must also be changed to produce flexible connection.
The representative mode of connection group of dry-type transformer is: English capital letters indicate the wiring on the primary side (or primary side) and English letters indicate the wiring on the secondary side (or secondary side). Y (or y) is star wiring， and D (or D) is triangular wiring.
Power transformers are also used for testing， which are called test power transformers. They can be divided into inflatable， oil transformer， dry test and other test power transformers. They are the basic test equipment for communication AC compression test for many consumers such as power stations， power supply bureaus and scientific research institutions. According to the specifications of the Bureau of quality supervision， It is used to carry out insulation compressive strength test under required current for various electrical products， electrical components and insulating raw materials.
High valueThe bearing capacity of each load is different. Generally， dry-type transformer should operate under rated capacity， while oil transformer has better load working capacity.
According to statistics， to occupy the main global technical position， the transformer industry depends on two key data， commodity volume and voltage level. As early as & ldquo; Eleventh Five Year Plan; In the early stage， China has been a powerful country in the production， manufacturing and application of dry-type transformers all over the world， first take out the low-voltage waterproof sleeve and the on load transformer power switch， then lower the bell cover anchor bolt of the large cover， slowly hang the galvanized steel wire rope with sufficient lifting net weight on the commonly used earrings， wear round steel from top to bottom in the surrounding screw holes， and count the spacing and specifications for easy reinstallation. At the same time， the cable wind shall be added on all sides to ensure that the core international body will not be damaged during the whole lifting process. After lifting for mm， stop the lifting， stabilize the bell cover， and check the bearing capacity of the lifting core， center of gravity and Jack. After everything is normal， lift it again until the bell cover exceeds the relative height of the body， and rotate the crane to place the bell cover on the clean skid.