We always recommend using an uninterruptible power supply (UPS) as a first step. Please to be sure that anything important to keeping your connection alive is connected to a UPS. This includes your modem, switches, etc!
Next, try using a different outlet or power supply to verify that another piece of hardware isn't causing this issue.
Most likely, this is an indicator of dirty building power. We recommend a conditioner or testing it in another location. Even moving the outlet may improve it.