Static electricity


Electricity that is stationary like the electric charge on an object.

Electrostatic motors driven by static electricity were manufactured experimentally earlier than electromagnetic motors. However, they were the same size as conventional motors and could hardly match electromagnetic motors in performance. The energy density of the electrostatic motor is much lower than that of electromagnetic motors because of the limitations of their dielectric strength. This is the reason why their practical application has been difficult. The miniaturization of electrostatic motors changes the sitter, and the breakdown voltage of solid insulation materials increases as they become thinner. With a thin insulation film, a breakdown voltage of 2 MV/cm can be easily obtained, and the electrostatic attraction force is quite strong at around 0.65 MPa. With insulation by gas, if the voltage is below the lower limit at which discharge starts as explained by Paschen's law, no discharge will occur even though the gap is small. Because this lower limit is 330 V in air, if, for example, 300 V is applied to a gap of 1 μm, an attraction force of around 0.4 MPa can be obtained.


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