S11-M-500KVA transformer can an be divided into three-phase transformers and single-phase transformers. In a three-phase power system, three-phase transformers are generally used. When the capacity is too large and limited by transportation conditions, three single-phase transformers can also be used in the three-phase power system to form a transformer group.
Winding division
S11-M-500KVA transformer can be divided into two-winding transformers and three-winding transformers. Common transformers are dual-winding transformers, that is, there are two windings on the iron core, one for the primary winding and one for the secondary winding. The three-winding transformer is a large-capacity transformer (above 5600 kVA) which is used to connect three different voltage transmission lines. In special cases, there are also Satons transformers with more windings.
Structural classification
S11-M-500KVA transformer can be divided into iron core transformers and iron shell transformers. If the winding is wrapped around the core, it is an iron core transformer. If the winding is wrapped around the core. S11-M-500KVA transformer is an iron shell transformer. The two are only slightly different in structure and there is no essential difference in principle. Power transformers are all iron-cored.
The transformer is mainly composed of iron core, winding, fuel tank, oil pillow, insulation sleeve, tap changer and gas relay.
Iron core of S11-M-500KVA transformer
The iron core is the magnetic circuit part of the transformer. During operation, heat is generated due to hysteresis loss and eddy current loss. In order to reduce heat loss and volume and weight, the core is made of cold-rolled grain-oriented silicon steel sheet with a high magnetic permeability of less than 0.35mm. According to the arrangement of windings in the iron core, there are iron core type and iron shell type.
In large-capacity transformers, in order to make the heat generated by the core loss can be sufficiently taken away by the insulating oil during circulation to achieve a good cooling effect, a cooling oil channel is often provided in the core.
Winding of S11-M-500KVA transformer
The windings and core are the core components of the transformer. Due to the resistance of the winding itself or the contact resistance at the joint.
S11-M-500KVA transformer is known that heat is generated. Therefore, the winding cannot pass a current higher than the rated current for a long time. In addition, transformers can be damaged by short-circuit currents that generate large electromagnetic forces on the windings. The basic winding has two types: concentric and overlapping.
The main faults of S11-M-500KVA transformer windings are shorts between turns and shorts to the case. Interturn short-circuit is mainly caused by insulation aging, or due to transformer overload and mechanical damage to the insulation during traversing short-circuits. When the oil level in the transformer drops, inter-turn short circuits can also occur when the windings are exposed to the oil surface. In addition, when there is a cross-over short circuit, the windings are deformed due to the effect of overcurrent, and the insulation is mechanically damaged, and inter-turn short circuits can occur. In the case of an interturn short circuit, the current in the short-circuit winding may exceed the rated value, but the entire winding current may not exceed the rated value. In this case, the gas protection is activated. When the situation is severe, the differential protection device is activated. The short circuit to the shell is also caused by aging of the insulation or oil dampness, oil level drop or lightning and operating overvoltage. In addition, when a short-circuit occurs, the winding of S11-M-500KVA transformer will be deformed due to overcurrent and a short-circuit to the case will also occur. When the case is short-circuited, it is generally the gas protection device action and the ground protection action.
3.Fuel tank
The body (winding and iron core) of the oil-immersed transformer is installed in a tank filled with S11-M-500KVA transformer oil, and the tank is welded with steel plates. The fuel tank of the medium and small transformer is composed of a tank shell and a tank cover. The body of the transformer is placed in the tank shell and the tank body can be lifted out for maintenance when the tank cover is opened.