The protection and safety of baoding dry type transformer is the key to transformer operation and an effective means to improve transformer protection. Transformer operation needs protection, we need to work together to maintain. So how to protect the transformer?
The faults of baoding dry type transformer can be divided into internal and external faults. Internal fault refers to all kinds of faults occurring in the transformer oil tank. External fault refers to all kinds of faults occurring in the external insulation sleeve of the oil tank and its leading line. In general, the transformer is removed by differential protection action. Quick action protection (gas and differential) no delay action to remove the fault transformer, equipment damage mainly depends on the dynamic stability of the transformer. And in the transformer side busbar and the connected interval of the lead out equipment fault, if the fault equipment is not equipped with protection (such as low-voltage side busbar protection) or protection refused to move, then only rely on the transformer backup protection action to jump corresponding switch to make the transformer out of fault. Due to the delayed action of the backup protection belt, the transformer must bear the over current caused by the out-of-area fault within a certain period of time. Whether the transformer is damaged within this period of time mainly depends on the thermal stability of the transformer. Therefore, there is an inevitable relation between the set value of transformer backup protection and the thermal stability requirement of transformer itself.
The setting value of transformer grounding fault protection has little relation with the load it carries, so the setting delay of backup protection for grounding fault is generally short, which can meet the requirement of 2s thermal stability time. Only the problem of setting value of transformer phase - to - phase backup protection is concerned. We suggest the following:
1) as an important electrical equipment in the power system, the design, manufacturing and operation of transformers should pay attention to their safety. The design of its dynamic and thermal stability should take full account of whether the transformers are running side by side, the number of transformers running side by side, the power supply on several sides and the neutral grounding mode of the power grid and other requirements.
2) in order to ensure the thermal stability of the transformer to withstand faults in operation, the manufacturer shall provide the relationship curve of the transformer winding fault current and the allowable time, which is similar to the A value requirement of the generator to withstand negative sequence.
3) the configuration and setting of baoding dry type transformer protection shall be configured with the corresponding protection according to the relation curve of the transformer winding flow fault current size and allowable time provided by the manufacturer.
4) the range of differential protection of baoding dry-type transformer shall include the low-voltage side switch, so that the fault between the low-voltage side switch and TA does not pose a threat to the thermal stability of the transformer.
5) the protection of baoding dry type transformer should be microcomputerized as far as possible, so that there can be more over-current protection sections, so that the over-current protection on each side can have relatively fast time delay switch on each side of the jumping transformer. In particular, the protection section of mid-low voltage side protection switch on each side of the jumping transformer is conducive to the failure point of the baoding dry type transformer as soon as possible.
Baoding zhongyi electric material manufacturing co., LTD. Is a professional transformer manufacturer in baoding transformer factory. It has professional production equipment, lifting equipment, tooling and testing equipment.
Main products: baoding dry type transformer, baoding box type transformer, baoding oil immersed transformer, baoding high and low voltage complete sets of equipment, etc. I companies to follow "detail decides success or failure, honesty molded the future" of the enterprise purpose, adhere to "quality measuring market, seek development by innovation, to management for efficiency" business philosophy, to make my company's products are widely used in power plant, chemical, construction, mining, metallurgy, rail transportation and other industries, to meet the needs of various users, my company rely on superior product quality, thoughtful service, won the trust of our customers.
