Answer:
The Fukushima plant explosions occurred at the nuclear facility, but they were hydrogen explosions (hydrogen exploding, not a hydrogen-bomb explosion), so no. It would take a much higher release of energy than a hydrogen explosion to generate a significant electro-magnetic pulse or EMP.
Nuclear plants can cause significant and very long-term damage when they melt down and impact a lot of people with the release of radioactive material, but are not capable of exploding like an "atomic bomb." Fission and fusion bombs have to be specially designed and engineered to create those EMP-inducing mega-explosions.