The Erebus driver put in a controlled performance over 250 kilometres to score a fourth victory of the season so far.
With team-mate Brodie Kostecki, who came into the race as the series leader, enduring a tough afternoon and finishing 19th, Brown secured a 43-point advantage at the top of the drivers' standings. Broc Feeney, who finished second on Saturday, is only a single point further back.
The race got off to an action-packed start courtesy of a rapid launch from van Gisbergen.
The Kiwi stormed off the second row of the grid to sweep past David Reynolds through Turn 1, before attempting to grab the lead from Brown down the inside of Turn 1.
Brown left van Gisbergen just enough space, but van Gisbergen couldn't slow his car enough for the tight right-hander, carting himself and Brown wide.
That allowed Cam Waters to sneak into the lead followed by Feeney with Brown resuming in third. Van Gisbergen found himself tangled with Jack Le Brocq and dropped all the way back to 14th.
Waters initially bolted to a one-second lead over Brown which he was able to maintain across the first 20 laps. It was at that point that he looked to lose his rear tyres, Brown quickly closing in before claiming the lead on lap 23.
Source: Autosport