Inductor saturation detection with anti-saturation control strategy applied

In this paper, detection of inductor saturation, together with anti-saturation control, is presented, which is applied to a synchronously-rectified (SR) buck converter. Since the inductor maybe sometimes work in a saturation situation, such as overload. In theory, as the inductor is saturated, the corresponding current slope in the inductor will be increased, and such a phenomenon can be used to judge whether the inductor is saturated or not. However, as this phenomenon occurs, variations in current are not easy to obtain because of limitations of slope detection speed and effects of noise interruption. Therefore, the detection of the inductor current ripple amplitude and the load current, together with the input voltage information, is used to judge whether the inductor is saturated or not. Afterwards, once the inductor is saturated, the proposed anti-saturation control strategy is applied to make the inductor work far from saturation. In this paper, some experimental results are provided to verify the proposed detection and compensation of inductor saturation.