alec_t,
From the first post, it looks like you are working on a buck PWM.
If you are just looking at gate drive then ...OK.
If you want a buck converter then this is not a good one. I have not run it on spice but, it looks like while the current builds up in the inductor, there is current in the MOSFET, that part is good. While the current in the inductor ramps down there is current flow in the MOSFET that is NOT GOOD!. You are missing a power diode form the MOSFET-drain to gnd.