Improvement Method for the Problem of High Temperature Rise of Switching Power Supply Transformer

During the working process of switching power transformer, engineers not only need to comprehensively consider the rationality of its design and construction, but also need to strictly control its temperature rise range to avoid the problem of excessive temperature rise leading to reduced working efficiency. In practical applications, excessive temperature rise often occurs in both the MOS transistor of the power transformer and the transformer design itself. Today, we will start from these two aspects to see how to effectively solve the problem of excessive temperature rise in switching power transformers.
First of all, from the perspective of the transformer itself, once the temperature rise is too high, scalding and heating occur, it is mainly caused by four issues, namely, copper loss, winding process issues, transformer iron loss, and transformer design power is too small. No-load heating refers to a transformer with a bad insulation or a high input voltage. If the insulation is bad, the coil needs to be rewound. If the input voltage is high, the input voltage needs to be reduced or the number of coils needs to be increased. "If the voltage is normal and the heat is hot when loaded, it means that the load on the power transformer is too large and the load design needs to be changed.".
In the design process of switching power supply transformers, the heating condition of MOS tubes is the most serious, and the excessive temperature rise of MOS tubes is caused by losses. The loss of MOS transistors consists of two parts: switching process loss and on state loss. To reduce on state loss, you can select a switch with a low on state resistance to reduce on state loss. Switching process loss is caused by the size of the gate charge and switching time. To reduce switching process loss, you can select devices with faster switching speed and shorter recovery time to reduce on state loss. However, it is more important to reduce losses by designing better control methods and buffer technologies, such as using soft switching technology, which can greatly reduce such losses.
In addition, there is another possibility that the temperature rise of the power transformer itself may be too high, which is that the transformer itself has experienced aging. When the engineer checks the transformer itself and the MOS tube and finds no abnormalities, it is necessary to make a comprehensive judgment based on the working time and service life of the transformer.