MEMS-based integrated inverter for wafer-scale thermionic energy converter

Patent metadata

Field	Value
Publication number	US-9590535-B2
Application number	US-201313944570-A
Country	US
Kind code	B2
Filing date	Jul 17, 2013
Priority date	Aug 17, 2012
Publication date	Mar 7, 2017
Grant date	Mar 7, 2017

Abstract

A thermionic energy converter is provided that includes an anode, a cathode, where the anode is disposed opposite the cathode, and a suspension, where a first end of the suspension is connected to the cathode and a second end of the suspension is connected to the anode, where the suspension moveably supports the cathode above the anode to form a variable gap between the anode and the cathode, where the variable gap is capable of enabling a variable thermionic current between the anode and the cathode, where the thermionic converter is capable of an AC power output.

First claim

What is claimed:

1. A thermionic energy converter, comprising:
a. an anode;
b. a suspended cathode, wherein said anode is disposed opposite said suspended cathode; and
c. a suspension, wherein said suspension comprises an electrostatic vertical comb drive and a MEMS bimorph, wherein a first end of said suspension is connected to said suspended cathode and a second end of said suspension is connected to said anode, wherein said electrostatic vertical comb drive is disposed to pull said cathode toward said anode, wherein said MEMS bimorph is disposed to repel said cathode from said anode, wherein said suspension moveably supports said suspended cathode above said anode to form a variable gap between said anode and said suspended cathode at a frequency of 60 Hz, wherein non-linear modulation of said gap is enabled by said electrostatic vertical comb drive, wherein said non-linear modulation of said variable gap is capable of enabling a variable thermionic 60 Hz current between said anode and said suspended cathode, wherein said thermionic converter is configured for generating a time-varying unipolar current.

2. The thermionic energy converter of claim 1 , wherein said cathode comprises a plate made from a refractory metal.

3. The thermionic energy converter of claim 1 , wherein a position sensor is integrated to said cathode to enable a closed-loop control of said cathode position, wherein control of said variable gap as a function of time is capable of outputting a current-voltage relationship that drives a resistive load for an optimal power transfer.

4. The thermionic energy converter of claim 3 , wherein said control of said variable is capable of outputting a sinusoidal current waveform.

5. The thermionic energy converter of claim 4 , wherein said sinusoidal current waveform has a DC offset.

6. The thermionic energy converter of claim 1 further comprising a second thermionic energy converter that is wired with opposite polarity to said thermionic energy converter, wherein said thermionic energy converter is disposed to produce an upper half of a sinusoidal voltage waveform, wherein said second thermionic energy converter is disposed to produce a bottom half of said sinusoidal voltage waveform, wherein a full sinusoidal voltage waveform is generated by non-linear modulation of each said variable gap, wherein said thermionic energy converter and said second thermionic energy converter are capable of a direct 60 Hz AC power output from modulating said suspended cathodes to match an AC frequency of a power grid.

Assignees

• Univ Leland Stanford Junior

Inventors

• Bargatin Igor
• Howe Roger T

Classifications

• B81B3/0032

  Structures for transforming energy not provided for in groups B81B3/0021 - B81B3/0029 · CPC title

• H02N3/00 Primary

  Generators in which thermal or kinetic energy is converted into electrical energy by ionisation of a fluid and removal of the charge therefrom (discharge tubes functioning as thermionic generators H01J45/00) · CPC title