Patent ID: 8183736

Claim:
A device for converting thermal energy to electric energy, comprising: a magnetic circuit including at least a portion made of a magnetic material; a temperature-varying device configured to vary a temperature in said portion made of the magnetic material alternately above and below a phase transition temperature of the magnetic material to thereby vary the reluctance of the magnetic circuit; a coil arranged around said magnetic circuit, in which electric energy is induced in response to a varying magnetic flux in said magnetic circuit; a capacitor connected in parallel with said coil to thereby form a resonant circuit, wherein the frequency of said temperature variation above and below the phase transition temperature and the resonance frequency of said resonant circuit optimize the resonant energy transfer to the resonance circuit, and wherein the ratio of the resonance frequency of said resonant circuit and the frequency of said temperature variation above and below the Curie temperature of the magnetic material is approximately n/2, wherein n is a positive integer.