I’d recommend first (if you don’t already have it) that you put the router (and all your other equipment) on a good surge suppressor or UPS.
Specific products aside, I’ve encountered more problems with “dirty” electricity than one can shake the proverbial stick at. – BobKberg
Cisco makes a great wireless product. It’s a bit pricey but for heavy traffic it works well. It also has better range than the Dlink will have, so better coverage.