This paper proposes an H-type magnetoelectric (ME) composite structure consisting of a fork Fe-Ni magnetostrictive substrate and PZT piezoelectric plates. The fork composite structure has a higher ME voltage coefficient and a higher ME power output relative to other ME composite structures due to its higher quality (Q) factor. The fork composite structure can obtain an output power of 61μW at an ac magnetic field of 0.2Oe. In order to increase the output power, a new power management circuit is presented, which can collect/store the energy in a long time and release the energy for driving load in a short time. Experiments show that the instantaneous discharge circuit can drive a WSN node with an output power of 75mW at a distance of over 60m.