A novel, very high efficiency, all inductive modulator

The authors present a closed-form derivation, proof-of-principle experiment, and design for a 1 MW physically realizable power conditioning modulator circuit. This modulator is an original, sequentially switched inductor network which produces a flat-topped current pulse, into a resistive load at efficiencies exceeding 90%. The energy contained in the mutual inductances is transferred into the load, while the self inductance energy is dissipated in the switches. The load to switch voltage ratio can easily exceed a factor of ten. A metal oxide varistor (MOV) is used across each opening switch, which both protects the switch from overvoltage and causes a linear current decay in the inductive loop being switched out. Furthermore, the MOV eliminates parasitic back-induced currents into previously switched out loops, and absorbs most of the energy required for switching. A 1 kW proof-of-principle experiment has been carried out, which fits the computer and analytic solutions perfectly. The design algorithms have been developed analytically and are simple to apply