How do you know it's a power related issue? The internal fan on the power supply is usually the air intake, and most cases are designed to have the fan facing down now. This gives the PSU it's own thermal intake/outlet path, and is usually plenty good for cooling the PSU. Unless the case is sitting on carpet, or the power supply is undersized or failing, you should not be experiencing power supply problems due to this.
If you are sure the cutouts are power related, you probably either need a new power supply, or, if you are experiencing power quality issues (whole house has lights flickering / appliances resetting), then you probably need a UPS or something to mitigate that.
Yea it started happening after I clean the vent filter where the power supply was located. I also unconnected the power cord since I need to do that to get the filter.