Have scientist invented anything to stop meteors from hitting our planet?

No! If a large asteroid (a tiny speck astronomically), say 2 miles across, was on collision course with our good Earth, it would probably mean the end of humanity and many other species too. We would have to discover such a mass of potential energy very early on to change its course significantly enough to miss the Earth, and a miss-calculation could make matters worse. As yet no such space missions are in place to use nuclear devices for the realignment or destruction of such energy packed bodies that litter the solar system. Just imagine what an asteroid with the mass of Everest and travelling at 40,000 miles per hour would do to our planet, and it is reasonably certain several such objects are on collision course to strike Earth within several thousand years from now if not tomorrow.