{"id":292,"date":"2009-12-13T23:37:33","date_gmt":"2009-12-14T06:37:33","guid":{"rendered":"http:\/\/cafe.foundation\/blog\/?p=292"},"modified":"2009-12-13T23:37:33","modified_gmt":"2009-12-14T06:37:33","slug":"the-prodigious-and-the-petite","status":"publish","type":"post","link":"http:\/\/cafe.foundation\/blog\/the-prodigious-and-the-petite\/","title":{"rendered":"The Prodigious and the Petite"},"content":{"rendered":"

We are endlessly fascinated by the largest, most powerful, or smallest and most infinitesimal of anything. Here we look at two extremes in electric propulsion.<\/p>\n

The Prodigious<\/strong><\/p>\n

American Superconductor <\/a>produces superconducting wires, and from those, winds a very large motor, that if not the biggest thing to power ships, is the most powerful for its size, and the most powerful to be used in a Navy ship.<\/p>\n

\"American

American Superconductor's 49,000 hp motor compared to largest, but less powerful, naval motor.<\/p><\/div>\n

The company promotes the following benefits for its 36.5 MW (49,000 horsepower) HTS (high temperature superconductor) motor: high power density (compared to traditional copper-wound motors), high partial load efficiency, low noise, harmonic-free voltage, low synchronous reactance, cyclic load insensitivity, and low maintenance.<\/p>\n

The Petite<\/strong><\/p>\n

Lad, living in St. Petersburg, Russia, has constructed the diametrical opposite of the HTS.\u00a0 His micro radio-controlled, electrically-powered model airplane weighs but 0.225 GRAMS –\u00a0motor, R\/C system, and battery. \u00a0In an R\/C forum<\/a>, readers were blown away by this accomplishment, needless to say, and the general hub-bub prompted this response from Lad.<\/p>\n

\"Lad's

Lad's 225 mg airplane.<\/p><\/div>\n

“Thank you all for the congratulations.<\/p>\n

“I cut 8.5 mAh Li-poly rebuilt up to 273 mg in halves in argon and sealed it with alu foil.
\nThe battery was cut 6 days ago – no capacity reduction over time so far.
\nIn the picture you’ll see the argon box. (Editor’s note<\/em>:This is Lad’s inert-gas-filled miniature clean room, to prevent fires\u00a0 from even this minuscule motivator. Li cells don’t take kindly to being punctured<\/em>.)<\/p>\n

“Motor<\/p>\n

“2 Magnets D 1mm L 0.5mm, rebuilt
\n2 Coils: wires D 0.02 , windings 220 , 72 ohms
\nGear-box 1 : 6.7<\/p>\n

“static thrust with prop d 25 x 15 0.14 gr
\ncurrent 24 mA”<\/p>\n

The video<\/a> cries out to be seen full screen, since the airplane is a brief flash in the lighter portions of the room. <\/p>\n