High power electrostatic motor and generator using electrets

For application to a micro-machined gas turbine, we first designed the motor/generator using electrets. Theoretical calculation confirmed that the motor/generator generates 30.4 W at a rotational speed of 1 Mrpm after its electrode design is optimized. Next, we proposed a novel circuit using LC resonance for the generator, which can avoid the charging-discharging loss of the parasitic capacitance. And we confirmed that the circuit could generate over 80% output of the theoretical maximum. Lastly, we developed an electret-charging equipment using Corona discharge. Using it, an electret was charged, showing the average surface voltage of 354 V and the standard deviation of 16 V.