Self-Excited, Alternating, High-Voltage Generation Using a Modified Electrostatic Influence Machine Available to Purchase

The principles of the classic rotary Wimshurst machine, which produces dc high voltage by regenerative electrostatic induction, are used to develop a new alternating high-voltage machine. This device has no electrical inputs but can spontaneously produce either dc or three-phase ac high voltage, depending on external connections. The machine constructed by the authors produces voltages in excess of 18 kV with frequencies of operation up to 2 Hz. Improved design can extend the voltage and frequency operating ranges. Analysis is extended to include multiphase, multi-frequency operation by modeling the device with a distributed equivalent circuit representation. The natural frequencies of the system are calculated where it is found that many overstable modes are present.