Power circuitry for high-frequency applications

1 . A power circuit comprising:

means for receiving a voltage input,

a transformer coupled between the voltage input and an output load,

a primary switching element coupled to a primary side of the transformer and a secondary switching element coupled to a secondary side of the transformer; and

a means for controlling the on-off operation of the primary and secondary switching elements, wherein the timing of the operation provides lossless switching and bidirectional power flow through the circuit.

2 . The power circuit of claim 1 is adapted for powering a capacitive device wherein operation of the switching elements provides charging and discharging of the device.

3 . The power circuit of claim 2 wherein the capacitive device is an EPAM actuator.

4 . The power circuit of claim 1 wherein each switching element comprises a semiconductor device.

5 . The power circuit of claim 4 wherein the semiconductor device is selected from the group comprising a MOSFET, BJT, IGBT and JFET.

6 . The power circuit of claim 1 wherein the means for controlling comprises means for measuring the voltage across and the current through each of the switching elements.

7 . The power circuit of claim 6 , further comprising means for timing the on-off operation of the switching elements, wherein the timing is derived from the switching element voltages and currents.

8 . The power circuit of claim 1 , wherein at least one of the switching elements comprises a plurality of serially connected stages, each stage having a voltage rating, wherein the voltage rating of the switching element is the sum of the stage voltage ratings.

9 . The power circuit of claim 8 , wherein each serially connected stage comprises a semiconductor device.

10 . A method of powering a device, comprising:

providing the power circuit of claim 1 and applying a voltage input to the power circuit;

(a) switching the primary switching element on when the voltage across the primary switching element is substantially less than a maximum voltage across the primary switching element thereby applying the voltage input to the primary side of the transformer and increasing the voltage across the secondary switching element;

(b) switching the primary switching element off thereby decreasing the voltage across the secondary switching element;

(c) switching the secondary switching element on when the voltage across the secondary switching element is substantially less than a maximum voltage across the secondary switching element;

(d) switching the secondary switching element off thereby decreasing the voltage across the primary switching element; and

repeating (a) through (d) as desired

11 . The method of claim 10 , wherein the switching on of each of the switching elements occurs when the voltage across the respective switching element is about zero volts.