The selection of the iron core is related to the voltage, while the selection of the wire is related to the current, that is, the thickness of the wire is directly related to the calorific value. In other words, the iya aiki of the transformer is only related to the heat generation. For a well-designed transformer, if it works in an environment with poor heat dissipation, if it is 1000KVA, if the heat dissipation capacity is enhanced, it may work at 1250KVA.

In addition, the nominal capacity of the transformer is also related to the allowable temperature rise. For example, if a 1000KVA transformer allows a temperature rise of 100K, if it can be allowed to work up to 120K under special circumstances, its capacity will be more than 1000KVA. . It can also be seen from this that if the heat dissipation conditions of the transformer are improved, its nominal capacity can be increased. Conversely, for a frequency converter with the same capacity, the volume of the transformer cabinet can be reduced.