Yes it is possible. One way to convert from 50Hz to 60Hz would be to first convert the 50Hz source to DC and then convert the DC to 60Hz using a 60Hz inverter. This is an entirely solid-state solution. The advantage being the conversion efficiency is very high. Also not having any moving parts makes this very reliable (provided cooling is good). The drawback is that the output may not be a "true" sine wave and may have a higher harmonics level. The result being more noise. But there are very few devices which would need anything better than this solution.