No-load characteristics of electret motor with brushes

An electret is a dielectric material that produces a quasi-permanent external field. Electrets have been utilized in a wide variety of applications. Electret motors utilizing the slot effect have been suggested by Jefimenko and Walker (1970, 1971). They have developed motors possessing good shielding and relatively large driving force. In these motors, the electric charges were sprayed on the electrodes of rotor by a corona discharge from point electrodes and the motors needed high voltages of several kilovolts for their operation. Thus, one can expect that electret motors with brushes should run at considerably lower voltages. The authors describe the fundamental characteristics of the electret motors with brushes under the no-load condition