1) Copper loss: The heat loss caused by the winding resistance, this is because the resistance is an energy dissipating element.
2) The hysteresis loss of iron (magnetic) core: that is, in the process of alternating magnetization of ferromagnetic materials, because the magnetic domain flip is an irreversible process, the change of the magnetic induction intensity always lags behind the change of the magnetic field intensity. This hysteresis The loss caused by the phenomenon in the iron (magnetic) core is called the hysteresis loss of the iron (magnetic) core.
3) Eddy current loss of iron (magnetic) core: When alternating current is passed through the winding coil, an alternating magnetic field will be generated around the coil, so that induced electromotive force and induced current will be generated in the iron (magnetic) core. This induction The current is called eddy current, and the resistance energy dissipation generated by the eddy current flowing in the iron (magnetic) core is called the eddy current loss of the iron (magnetic) core.
(5) Frequency characteristics. The frequency characteristic means that the transformer has a certain working frequency range, and transformers with different working frequency ranges generally cannot be used interchangeably. Because the transformer works outside its frequency range, the temperature will rise during operation or it will not work properly.
(6) Insulation resistance. Insulation resistance refers to the resistance between each coil of the transformer and between each coil and the iron core (shell). Its size is related to the size and time of the voltage applied by the transformer, its own humidity and the humidity of the insulating material. The insulation resistance of an ideal transformer should be infinite, but the insulation of the actual transformer material itself cannot be very ideal, so its insulation resistance cannot be infinite. Insulation resistance is the ratio of the applied test voltage to the resulting leakage current.
Insulation resistance is a parameter to measure the insulation performance of a transformer. If the insulation resistance of the power transformer is too low, there may be a short circuit between the primary and secondary or the short circuit of the iron core shell, causing damage to the electrical equipment or the danger of the chassis being charged. Under normal circumstances, between the primary and secondary coils of the power transformer, and between them and the iron core, there should be insulation properties that can withstand 1000V AC voltage without being broken down within 1min. When testing with lkV insulation resistance meter, the insulation resistance should be above 10MQ.
(7) Leakage inductance. The magnetic flux generated by the current in the primary coil of the transformer does not all pass through the secondary coil, and this part of the magnetic flux that does not pass through the secondary coil is called leakage flux. The inductance caused by the leakage flux is called leakage inductance. The existence of leakage inductance not only affects the efficiency and other performance of the transformer, but also affects the circuit operation around the transformer, so the smaller the leakage inductance of the transformer, the better.
(8) Temperature rise. The temperature rise of the transformer is mainly for the power transformer. It means that when the temperature of the transformer rises to a stable value after it is powered on, the temperature of the transformer is higher than the ambient temperature. The smaller the temperature rise of the transformer, the better. However, it should be pointed out that sometimes the maximum operating temperature is used instead of temperature rise in the parameters.