Switching power supply transformer classification introduction
Switching power transformer is a power transformer with added switching tubes. In addition to the voltage conversion function of ordinary transformers, switching power transformers also have insulation isolation and power transmission functions in circuits. Switching power transformers are generally used in applications involving high-frequency circuits such as switching power supplies.
The function of switching power transformer
The switching power transformer and switch tube together form a self-excited (or separately excited) intermittent oscillator, which modulates the input DC voltage into a high-frequency pulse voltage
Plays a role in energy transfer and conversion In a flyback circuit, when the switching transistor is turned on, the transformer converts electrical energy into magnetic field energy and stores it. When the switching transistor is turned off, it is released In a forward circuit, when the switching transistor is turned on, the input voltage is directly supplied to the load and energy is stored in the energy storage inductor When the switch tube is turned off, the energy storage inductor continues to transfer the current to the load
Convert the input DC voltage into various required low voltages
Classification of Switching Power Transformers
Switching power transformers are divided into single excitation switching power transformers and double excitation switching power transformers, and the working principles and structures of the two types of switching power transformers are not the same. The input voltage of a single excited switching power supply transformer is a unipolar pulse, and it is also divided into forward and reverse voltage outputs; The input voltage of a dual excitation switching power supply transformer is a bipolar pulse, usually a bipolar pulse voltage output.
Characteristic parameters of switching power transformer
Voltage ratio: refers to the ratio of the primary voltage to the secondary voltage of a transformer
DC resistance: also known as copper resistance
Efficiency: i.e. output power/input power * 100 [%]
Insulation resistance: The insulation ability between the windings of a transformer and between the iron cores
Electrical strength: The degree to which a transformer can withstand a specified voltage within 1 second or 1 minute
