First let me preface my question with the fact that I am ignorant to electricity hence my lack of understanding to technical jargon.
I am running an air compressor in my warehouse that has a motor with 230v capacity.
Upon examination my electrician discovered that the power in the building is 245v.
Needlessto say I have gone through five compressors in 2 years.
Is therea step down transformer that can reduce the voltage going to the compressor to between 220 and 230 v

Your electrician should be aware of what is called a "Buck-Boost" transformer. If yours does not know about them I doubt he will know how to chose the correct size and voltage rating, so you need to find an electrician that is fully knowledgeable of these.

Or you could find a 240 volt rated motor.