Voltage Improvement With Diesel Generator

If it's big enough, yes. And your power company will be very happy, too. They may also give you a medal of honor. And then you may sell it to buy something to eat. S.M.

What is your Power Factor? How fare are you from the substation / end of the line? 

Your probablem could just be due to additional AC loads on you circuit causing excessive line heating that increases the resistance. If this is the case your power co can probably solve the problem with a cap bank on your circuit. 

Copper resistance, aluminum transmission cable resistance goes up, magnetization of iron based laminate goes down with temperature. Depends on the particulates. Any more questions, as it is well known?

Move the tap on the transformer, maybe back and forth on a seasonal basis if power factor correction, as astutely suggested above, doesn't bail you out.

If you need the correct voltage, separate yourself from the mains and use the generator to supply your house.

Trying to "pull up" the mains as you describe will be expensive for you, but will bring a smile to the neighbour's faces....

Find out exactly what is the voltage you are getting from the power company, check for for variances to identify when exactly do you get volt drop

Check power factor

Check your load profile- balance and peaks at all your load centres

Do these investigations first to identify cause .

JS

I just had an idea about what you are really thinking of attempting to do with the mains in your area, is almost like a friend of mine some years ago, he "attempted" to "download" the internet.......wanted to have it on his BIG hard disk!!! (all of 6GB I think at the time.....)

Its similar!!!!