What effect will the leakage inductance of the common mode inductor have on its surrounding circuits, and how to control the leakage inductance?
Publish Time: 2024-08-10
The leakage inductance of the common mode inductor has an important impact on the surrounding circuits.
First, the leakage inductance will interfere with the signal transmission of the surrounding circuits. When the leakage inductance exists, it will form an additional inductance path in the circuit. In high-frequency signal transmission, the leakage inductance may cause signal reflection and attenuation. For example, in communication circuits, this may cause signal distortion and reduce communication quality. Moreover, the leakage inductance may also produce coupling effects with other components in the surrounding circuits, causing unnecessary electromagnetic interference. For example, it may interfere with nearby sensitive electronic components such as amplifiers, sensors, etc., causing their working performance to deteriorate.
Secondly, the leakage inductance will affect the power transmission efficiency of the circuit. In some power conversion circuits, the leakage inductance will cause energy loss. When the current passes through the common mode inductor, a certain voltage drop will be generated on the leakage inductance, and this part of the energy will be consumed in the form of heat energy, thereby reducing the efficiency of the entire circuit. Especially in high-power applications, the energy loss caused by the leakage inductance may be more significant.
In order to control the leakage inductance of the common mode inductor, the following methods can be adopted. The first is to optimize the winding structure. Use a suitable winding method, such as sandwich winding, to symmetrically wind the two windings on the core and couple them closely. This can reduce leakage flux and thus reduce leakage inductance. The second is to choose a suitable core material and shape. Some core materials with high magnetic permeability and closed magnetic circuits, such as toroidal ferrite cores, can effectively reduce leakage flux. At the same time, reasonably designing the size and shape of the core so that it can better guide the magnetic field can also help reduce leakage inductance. Third, when designing the circuit, some compensation components can be added to offset the effect of leakage inductance. For example, in some switching power supply circuits, some capacitors can be added to compensate for the voltage spikes caused by leakage inductance and improve the stability of the circuit. In short, understanding the impact of common mode inductor leakage inductance on peripheral circuits and taking effective control measures are of great significance to improving the performance and reliability of the circuit.
