Inductors are electronic components that can store and release energy. When an inductor passes through a current, a magnetic field will be generated around it, which is the inductive reactance of the inductor. In the DC circuit, the inductance of the inductance is shown as resistance, while in the AC circuit, the inductance of the inductance will affect the frequency and phase of the current.
Inductors in switching power supply are usually used for filtering, energy storage, voltage boost and other purposes. The filtering function is mainly to reduce ripple and noise in AC current and improve power quality. The energy storage function is to convert electric energy into magnetic energy and store it, and then release it when needed to meet the load demand. The boost function is to raise the lower voltage to a higher voltage to meet the power supply demand of some equipment.
The placement of inductance in switching power supply is very important for its performance and stability. In general, the electric induction shall be as close to the switch tube as possible or DAC7578SPWR Rectifier diode and other heating devices to better heat dissipation. In addition, the inductance should be far away from electromagnetic interference sources, such as other switching elements and cables, to reduce the impact of interference on the inductance performance.
The five major reasons for the burnout of the output inductance of the switching power supply are as follows:
1. Overload operation: When the output power of the switching power supply exceeds its rated power, the inductance will be heated due to overload, and the overload operation for a long time will lead to the burning of the inductance.
2. Too high temperature: the ambient temperature around the inductance is too high, or the inductance itself has poor heat dissipation, which may cause its temperature to rise, and then burn the inductance.
3. Manufacturing quality problems: If the wire diameter of the inductance is too thin, the winding is not tight, or the material quality is poor, the resistance of the inductance may increase, the temperature rise may increase, and eventually the inductance will be burned.
4. Reverse voltage: when the reverse voltage at both ends of the inductance exceeds its rated value, the inductance will be damaged due to reverse breakdown. This may be caused by unreasonable circuit design, unstable input voltage or sudden load disconnection.
5. Excessive current: When the current flowing through the inductance exceeds its rated value, the inductance will be burned due to overheating. This may be caused by circuit short circuit, overcurrent protection failure or load sudden change.
The following measures can be taken to avoid burnout of the output inductance of the switching power supply:
● Reasonably design the circuit to ensure that the output power does not exceed the rated power of the inductance.
● Keep the ambient temperature around the inductance appropriate, and take effective heat dissipation measures, such as installing radiators or fans.
● Select inductance with reliable quality, pay attention to wire diameter, winding quality, material selection, etc.
● Add over-current protection device in the circuit. Once the current exceeds the rated value, it will automatically cut off the power supply to protect the inductance and other devices from damage.
● Strengthen circuit monitoring and management, timely find and deal with fault conditions, and avoid abnormal conditions such as sudden load changes that lead to the burning of inductance.
In order to prevent these problems, designers need to carefully consider all aspects of power supply design, including selecting appropriate inductance devices, ensuring quality control, carrying out appropriate thermal management and circuit protection measures, and fully considering the stability and reliability of the system under various operating conditions.
