Pulsed start-up system for electrostatic generators
View Patent ↗A new rotor start-up system is provided for application to rotating systems such as stationary or vehicular electromechanical battery systems. An embodiment of the system consists of a “locator” that includes a stationary permanent-magnet pole above which is a circular ferromagnetic (e.g., iron) strip embedded in the lower, inner edge of the flywheel rotor. The lower edge of this strip is wave-like so that the magnet can pull the rotor around to a position where the position relative to the minimum capacity between the rotor and stator electrodes is such as to launch the rotor in a chosen direction, i.e., either clock-wise or counter-clockwise. Startup from rest is then accomplished by applying a short high-voltage ac or dc pulse to the EMB capacitor.
1. An apparatus, comprising:
a rotor configured to rotate about a central axis;
a first plurality of electrodes fixedly attached to said rotor;
a magnetic locating system comprising:
a ferromagnetic strip fixedly connected to said rotor and having a wave-like edge extending away from said rotor; and
a permanent magnet having a pole spaced from said wave-like edge such that when said rotor rotates, the gap between said pole and said wave-like edge varies;
a stator centered on said central axis;
a second plurality of electrodes fixedly attached to said stator; and
a pulse drive circuit connected to said second plurality of electrodes, wherein said wave-like edge is positioned so that said pole can pull said first plurality of electrodes around to a position where the position relative to the minimum capacity between said first plurality of electrodes and said second plurality of electrodes is such as to launch said rotor in a chosen direction.
2. The apparatus of claim 1 , wherein when said pulse drive circuit is activated, it will generate an azimuthally directed force on said first plurality of electrodes, starting from the initial azimuthal position of said first plurality of electrodes as determined by said magnetic locating system.
3. The apparatus of claim 1 , wherein said pulse drive circuit is configured to start the rotation of said rotor by applying a high-voltage ac or dc pulse to said second plurality of electrodes.
4. The apparatus of claim 1 , wherein said first plurality of electrodes together with said second plurality of electrodes form a first variable capacitor and wherein said magnetic locating system is configured to position the resting azimuthal position of said rotor to be slightly clockwise or slightly counter-clockwise from any one of the multiple azimuthal positions of minimum capacity of said first variable capacitor.
5. The apparatus of claim 1 , wherein said ferromagnetic strip is fixedly attached to the inner radius of said rotor structure.
6. The apparatus of claim 1 , wherein said wave-like edge comprises a minima having a depth configured to achieve, a desired value of locating force.
7. The apparatus of claim 1 , wherein said pulse drive circuit is configured to produce a square wave.
8. The apparatus of claim 1 , wherein said magnet comprises ceramic type magnet material and is wrapped with a coil.