An energy extraction circuit for extracting electrical energy from a charged-particle beam, comprising: a grid-tied bidirectional converter couplable to an electrical power utility grid, said grid-tied bidirectional converter configured to deliver a direct current voltage and to provide electrical energy; and a resonant converter comprising a multi-pole inverse cyclotron converter, an inductor, and a plurality of circuit switches (S1, S2, S3, S4), wherein the multi-pole inverse cyclotron converter includes two or more elongated plates with arcuate cross-sections forming an elongated annular-cylindrical chamber with axially extending elongated gaps formed between the two or more elongated plates, wherein the two or more elongated plates are arranged to function as a capacitor which, combined with the inductor, is configured to form a resonant tank, wherein the plurality of circuit switches (S1, S2, S3, S4) are configured to form a bridge configured to chop the direct current voltage received from the grid-tied bidirectional converter to a pulse waveform, wherein the multi-pole inverse cyclotron converter, when current is applied to the two or more elongated plates,, is configured to form a multi pole electric field across the elongated gaps between the elongated plates that decelerates charged particles of charged-particle beams passing through the cylindrical chamber to extract electric energy from the kinetic energy of the charged particles, wherein the grid-tied bidirectional converter is configured to establish the resonance of the multi-pole inverse cyclotron converter by providing the electrical energy to said multi-pole inverse cyclotron converter. a grid-tied bidirectional converter couplable to an electrical power utility grid, said grid-tied bidirectional converter configured to deliver a direct current voltage and to provide electrical energy; and a resonant converter comprising a multi-pole inverse cyclotron converter, an inductor, and a plurality of circuit switches (S1, S2, S3, S4), wherein the multi-pole inverse cyclotron converter includes two or more elongated plates with arcuate cross-sections forming an elongated annular-cylindrical chamber with axially extending elongated gaps formed between the two or more elongated plates, wherein the two or more elongated plates are arranged to function as a capacitor which, combined with the inductor, is configured to form a resonant tank, wherein the plurality of circuit switches (S1, S2, S3, S4) are configured to form a bridge configured to chop the direct current voltage received from the grid-tied bidirectional converter to a pulse waveform, wherein the multi-pole inverse cyclotron converter, when current is applied to the two or more elongated plates,, is configured to form a multi pole electric field across the elongated gaps between the elongated plates that decelerates charged particles of charged-particle beams passing through the cylindrical chamber to extract electric energy from the kinetic energy of the charged particles, wherein the grid-tied bidirectional converter is configured to establish the resonance of the multi-pole inverse cyclotron converter by providing the electrical energy to said multi-pole inverse cyclotron converter.