Research On Amorphous Alloy Dry-type Transformer Electromagnetic And Thermal Properties

Amorphous alloy dry-type transformer is one type of new energy-saving transformer. Theapportionment of this kind transformer is increasing in market because of the needs of energysaving and the lower price of amorphous materials. How to reduce the loss of transformer andreduce the temperature rise are the problems that needed to solve in the power system. Thecore of transformer used by ordinary silicon steel has larger loss than the core used byamorphous materials. Due to the different structure of the amorphous alloys dry-typetransformer, the loss distribution and temperature rise of the transformer should be calculatedaccurately that is the key to ensure the transformer run safely, efficiently and stably.Combined the research status of the electromagnetic and temperature rise calculation ofdry-type transformer at home and abroad and according to the basic principle of transformer,the distribution of leakage magnetic field of amorphous dry-type transformer is analyzed andthe amorphous core loss is calculated by the finite element in this article, the loss distributionof multilayer foil type winding is summarized in the end. The relationship between foilwindings and leakage flux also has been researched further.In the calculation of temperature field and fluid field, firstly, the theory and simulationmethod of heat transfer and fluid mechanics are introduced. The temperature field and flowfield were calculated with this method of ordinary630kVA/10kV dry type transformer andamorphous100kVA/400V dry type transformer. Then the experimental platform is set up tomeasure the surface temperature of the resin under short circuit, the loss that used as a sourceof heat is calculated by using the short circuit current to calculate the temperature field andfluid field of the transformer, with compared the simulation results and experimental results,the temperature value of relative error is within10%. Secondly, the distribution of temperaturefield and fluid field of each part of the amorphous dry-type transformer are calculated by usingthe method above, then the simulation results of the temperature field were compared with theactual average temperature to verify the accuracy of the calculating method and the reason thatgenerated error are summarized. The two-dimensional model of the transformer isestablished on this basis to calculate the temperature rise of windings meticulously. Finally,the temperature field and flow field are analyzed under the condition of different tap situationand different load coefficient. On this basis, the temperature rise and the flow rate are analyzedby changing the baffle position, and the conclusion is given. It has certain guiding significancefor optimization to the structure of the transformer.