Structure of chip radiator for outdoor copper winding oil-immersed transformer
The heat of the transformer comes from two aspects: 1. Iron loss is the heat generated by the eddy current in the transformer core; 2. The heat generated by the load current flowing through the transformer winding. If too much heat can't be dissipated in time, it will reduce the work efficiency and cause an explosion. In order to speed up heat dissipation, the outdoor copper winding oil-immersed transformers are equipped with heat sinks. The chip radiator is the most widely used radiator. Compared with the tube radiator, it has the advantages of saving material, light weight, saving 2/3 of transformer oil, reducing cost by 6.47%, and high cooling efficiency. However, the welding process is demanding and the mechanical strength is poor.
The chip radiators can be divided into two categories depending on how they are fixed in the transformer tank.
(1) Fixed type (PG, P-chip type, G-fixed): Solder directly on the wall of the transformer tank, generally used on distribution transformers. Based on the transport size, when the shortest axial width exceeds the transport allowable size, a detachable type is considered.
(2) Removable type (PC, C-detachable): It is fastened to the pipe joint of the transformer tank wall by flange, and is generally used for power transmission and transformation. It has upper and lower plugs, which are used for deflation and oil discharge respectively.
The chip radiator is blown by a blowing device (fan), which can improve the heat dissipation effect. The blowing method is divided into a side blowing type, a bottom blowing type and a mixed blowing type, and the air flow resistance of the bottom blowing type is the smallest.
The chip radiator has simple installation, no noise, low auxiliary machine loss, low failure rate, low maintenance workload, etc. compared with the strong oil air cooler and strong oil water cooler which are usually used as cooling devices for large and extra large transformers. The advantages, but it has the disadvantages of low cooling efficiency, large floor space, large number of cooling groups, large oil consumption, etc., thus limiting its application on large and extra large transformers. In response to this problem, in the 1990s, the domestic absorption of European technical experience, the widespread use of chip radiators in strong oil-air cooling, that is, the chip radiator with fans and oil pumps for cooling. This cooler device, also known as a cooling cooler, has the following advantages:
(1) The corresponding cooling method can be determined according to the needs of the transformer load condition. When the transformer load is low, the chip radiator can be self-cooling, that is, it operates in oil-immersed self-cooling mode (ONAN); when the transformer load rate reaches about 75%, the fan starts, and the chip radiator is in oil-immersed wind. Cold mode (ONAF) operation; when the transformer is fully loaded, the oil pump is put into operation, and the chip radiator operates in the strong oil air cooling mode (OFAF).
(2) The heat sink cooler fundamentally overcomes the drawback of low cooling efficiency of the chip radiator. When the transformer is fully loaded, the cooling cooler achieves a cooling efficiency comparable to that of a strong oil cooler. When the transformer load is low, since the cooling cooler uses an axial flow oil pump, even if the oil pump does not start, the oil flow between the chip radiator and the transformer body can be naturally circulated through the pipeline and the oil pump. Therefore, the fan and the oil pump are not activated, and the purpose of effective cooling can be fully achieved. In this way, not only the noise is reduced, but also the service life of the fan and the oil pump can be extended, and the loss rate of the auxiliary machine can be reduced.
ZTELEC has been working on the transformer factory for ten years. It has been committed to the integrated R&D, production, sales and service of transmission and distribution systems. It aims to provide users with safer, more reliable, smarter and greener electrical solutions, so that electricity can change the world. In the process of intellectual change, let the electricity do its best. Choose high quality outdoor copper winding oil-immersed transformer
The chip radiators can be divided into two categories depending on how they are fixed in the transformer tank.
(1) Fixed type (PG, P-chip type, G-fixed): Solder directly on the wall of the transformer tank, generally used on distribution transformers. Based on the transport size, when the shortest axial width exceeds the transport allowable size, a detachable type is considered.
(2) Removable type (PC, C-detachable): It is fastened to the pipe joint of the transformer tank wall by flange, and is generally used for power transmission and transformation. It has upper and lower plugs, which are used for deflation and oil discharge respectively.
The chip radiator is blown by a blowing device (fan), which can improve the heat dissipation effect. The blowing method is divided into a side blowing type, a bottom blowing type and a mixed blowing type, and the air flow resistance of the bottom blowing type is the smallest.
The chip radiator has simple installation, no noise, low auxiliary machine loss, low failure rate, low maintenance workload, etc. compared with the strong oil air cooler and strong oil water cooler which are usually used as cooling devices for large and extra large transformers. The advantages, but it has the disadvantages of low cooling efficiency, large floor space, large number of cooling groups, large oil consumption, etc., thus limiting its application on large and extra large transformers. In response to this problem, in the 1990s, the domestic absorption of European technical experience, the widespread use of chip radiators in strong oil-air cooling, that is, the chip radiator with fans and oil pumps for cooling. This cooler device, also known as a cooling cooler, has the following advantages:
(1) The corresponding cooling method can be determined according to the needs of the transformer load condition. When the transformer load is low, the chip radiator can be self-cooling, that is, it operates in oil-immersed self-cooling mode (ONAN); when the transformer load rate reaches about 75%, the fan starts, and the chip radiator is in oil-immersed wind. Cold mode (ONAF) operation; when the transformer is fully loaded, the oil pump is put into operation, and the chip radiator operates in the strong oil air cooling mode (OFAF).
(2) The heat sink cooler fundamentally overcomes the drawback of low cooling efficiency of the chip radiator. When the transformer is fully loaded, the cooling cooler achieves a cooling efficiency comparable to that of a strong oil cooler. When the transformer load is low, since the cooling cooler uses an axial flow oil pump, even if the oil pump does not start, the oil flow between the chip radiator and the transformer body can be naturally circulated through the pipeline and the oil pump. Therefore, the fan and the oil pump are not activated, and the purpose of effective cooling can be fully achieved. In this way, not only the noise is reduced, but also the service life of the fan and the oil pump can be extended, and the loss rate of the auxiliary machine can be reduced.
ZTELEC has been working on the transformer factory for ten years. It has been committed to the integrated R&D, production, sales and service of transmission and distribution systems. It aims to provide users with safer, more reliable, smarter and greener electrical solutions, so that electricity can change the world. In the process of intellectual change, let the electricity do its best. Choose high quality outdoor copper winding oil-immersed transformer