Test And Analysis Of Magnetic Saturation Current For Power Inductor

In the modern electronic products, switch mode power supply is widely used to provide various DC power supply. One of the core components of the switch mode power supply is the magnetic components. While magnetic saturation is the common property of the magnetic elements. In practical application, magnetic saturation often causes fever and even burned circuit components. Therefore, to test the magnetic saturation current is very necessary.This thesis is mainly based on the electromagnetic theory, and introduces the design of power inductor for switch mode power supply. The power inductance characteristic curve is analyzed in detail. The method of half bridge circuit proposed to measure the power inductance current, the measurement circuit designed and builded to measure magnetic saturation current. The circuit output two square wave signals with frequency and duty cycle adjustable by pulse width modulation chip, in order to control power driving chip which driving two power field effect transistors to form half bridge drive circuit. Testing power inductors made by different types of cores though the test circuit, and analyzing magnetic saturation current data. By analyzing the data can obtain the relationship between the size of magnetic saturation current and power inductor turns, frequency, voltage, duty cycle and other related parameters; at rated output current, the link between the decline of the inductance power inductor and the degree of magnetic saturation. Those provide a reference for practical application. In addition, this paper supplements the effect of temperature on test results and the influence of frequency on core loss. Experiment results verify that the design of the test circuit can measure the magnetic saturation current of power inductor on the premise of safety. The design is reach the requirement.