How to design a peak current limiter using opamps?

Thread Starter

Xavier Pacheco Paulino

Joined Oct 21, 2015

I'm simulating a non-inverting buck-boost converter using LTSpice. I'm getting the expected output voltages at each operating point, but the inductor saturates in the transition from buck mode to boost mode. See simulation files and pictures. You can see in Fig1 how blue waveform, which is the inductor current, goes too high at that point indicating that it has saturated. How can I eliminate this behavior? I'm using average current mode control, and I think that's why I have issues with the peak current, as this method does not actually handle it. So I thought of designing another opamp current limiter circuit. What are your thoughts? If you need more details, let me know. I took this exercise from Power Electronics online course on Coursera.