I am currently studying power electronics and trying to truly understand the operation of buck and boost converters. From the Wikipedia page for a buck converter, it states, "When the switch is first closed (on-state), the current will begin to increase, and the inductor will produce an opposing voltage across its terminals in response to the changing current". This sentence really puzzled me because I had always been under the impression that a change in voltage across the inductor caused the current to change.
Even in my power electronics class, my professor discussed how the difference in the voltage across the inductor from input voltage to output voltage, causes the inductor current to ripple. We calculated the inductor ripple by using the voltage across the inductor for the on time of the active switch and solving the differential equation . However, from this Wikipedia article, it seems that the ripple in inductor current actually is what is causing the change in voltage from input to output.
So which one is it? Does a voltage differential across the inductor cause the current to start ramping up, or does a change in current induce a voltage differential?