No-load current:
The low-power power transformer applies a rated voltage to the primary winding in the case where all secondary windings are open, and the current through the primary winding is called the primary no-load current Iio, which is one of the important parameters for measuring the quality of the low-power power transformer. When the secondary power supply transformer is fully loaded (rated load) and the primary rated voltage is applied, the current through the primary winding is called the primary rated current Ii.
According to the recommended values of the relevant standards and a large number of practices, the maximum value of the no-load current Iio of the low-power power transformer should not exceed 5 to 8% of Ii. If the no-load current exceeds 10% of the rated current, the loss of the transformer will increase; when the no-load current exceeds 20% of the rated current, the transformer will not be used because its temperature rise will exceed the allowable value and the working time will be slightly longer. Seriously, it will lead to burning accidents.
The no-load current consists of magnetizing current (generating magnetic flux) and iron loss current (caused by core loss).
In order to reduce the no-load current, it is mainly from the core of the transformer.
1. Improve the quality of silicon steel sheets.
2. Improve the core structure.
3. Change the power conversion mode. |
