A Buck-Boost Converter, comprising: first and second switch arrays (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l; S 4u, S 4l, S 5u, S 5l, S 6u, S 6l), each comprising at least two switching devices; a parallel inductor-capacitor combination (120, 121), forming a reactance, connected to each said switch array; wherein: a first one of said switch arrays (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l) is operatively connected to a power input, and is operated to drive power into said inductor-capacitor combination (120, 121) with a non-sinusoidal waveform; and a second one of said switch arrays (S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) is operated to extract power from said inductor-capacitor combination (120, 121) to a power output; the at least two switching devices of each of said first and second switch arrays (S 1u, Sn, S 2u, S 2l, S 3u, S 3l; S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) are bidirectional switching devices; the at least two switching devices of said first switch array (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l) are jointly connected to operatively connect at least one terminal of said inductor-capacitor combination (120, 121) to said power input with reversible polarity of connection, and configured to drive said inductor-capacitor combination (120, 121) with a full AC waveform at a base frequency which is less than half the resonant frequency of said reactance; and the at least two switching devices of said second switch array (S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) are jointly connected to operatively connect at least one terminal of said inductor-capacitor combination (120, 121) to said power output with reversible polarity of connection. first and second switch arrays (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l; S 4u, S 4l, S 5u, S 5l, S 6u, S 6l), each comprising at least two switching devices; a parallel inductor-capacitor combination (120, 121), forming a reactance, connected to each said switch array; wherein: a first one of said switch arrays (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l) is operatively connected to a power input, and is operated to drive power into said inductor-capacitor combination (120, 121) with a non-sinusoidal waveform; and a second one of said switch arrays (S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) is operated to extract power from said inductor-capacitor combination (120, 121) to a power output; the at least two switching devices of each of said first and second switch arrays (S 1u, Sn, S 2u, S 2l, S 3u, S 3l; S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) are bidirectional switching devices; the at least two switching devices of said first switch array (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l) are jointly connected to operatively connect at least one terminal of said inductor-capacitor combination (120, 121) to said power input with reversible polarity of connection, and configured to drive said inductor-capacitor combination (120, 121) with a full AC waveform at a base frequency which is less than half the resonant frequency of said reactance; and the at least two switching devices of said second switch array (S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) are jointly connected to operatively connect at least one terminal of said inductor-capacitor combination (120, 121) to said power output with reversible polarity of connection. a first one of said switch arrays (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l) is operatively connected to a power input, and is operated to drive power into said inductor-capacitor combination (120, 121) with a non-sinusoidal waveform; and a second one of said switch arrays (S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) is operated to extract power from said inductor-capacitor combination (120, 121) to a power output; the at least two switching devices of each of said first and second switch arrays (S 1u, Sn, S 2u, S 2l, S 3u, S 3l; S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) are bidirectional switching devices; the at least two switching devices of said first switch array (S 1u, S 1l, S 2u, S 2l, S 3u, S 3l) are jointly connected to operatively connect at least one terminal of said inductor-capacitor combination (120, 121) to said power input with reversible polarity of connection, and configured to drive said inductor-capacitor combination (120, 121) with a full AC waveform at a base frequency which is less than half the resonant frequency of said reactance; and the at least two switching devices of said second switch array (S 4u, S 4l, S 5u, S 5l, S 6u, S 6l) are jointly connected to operatively connect at least one terminal of said inductor-capacitor combination (120, 121) to said power output with reversible polarity of connection.