Jeff's Blog

My daily (well I am trying to update daily now) weblog covering topics such as wind power, embedded electronics, software development, CNC Machines and some fun stuff like travel and sailing.

Monday, May 19, 2008

VAWT Video Part 2 - Power Generation.

VAWT Part 2 -- Gears and Generator

Please check out the following link to a YouTube Video of part two of our wind turbine build. Video - Part 2 This shows our geared generator design and a desktop CNC machine cutting gears.

Two other designs are being worked on for future:

1. Geared design shown in this video.

2. A version with a built in rotating cylinder of permanent magnets exciting a stationary coil (permanent magnet alternator) with no mechanical gearing and hence no mechanical loss as is inherent with gears.

3. Another type with a geared automotive generator (no magnets at all) whose mechanical resistance is controlled with PWM(Pulse Width Modulation) by a microcontroller controlling power into the rotating coil. With no power, the coil should free-wheel with minimal resistance. In strong winds, we could "make hay while the sun shines" by putting a lot of juice into the coil. In light winds, the power in the coils is reduced to an amount which still will at least hopefully trickle charge the battery. A small permanent magnet motor-generator would be used to jump start the process and handle the case of a totally dead battery, and could "trickle charge" a dead battery. This design is very interesting from a software point of view, but has the highest amount of technical risk.

The wind speed, RPM, and outputs will be monitored, and more importantly compared, with a flexible sensing and visual programming environment called NeatTools, which will be discussed and "filmed" in future posts. We will also be using a TNG-3B from in conjunction with NeatTools to simultaneously monitor multiple inputs from hall effect sensors (from a small magnet on each turbine axle), voltage sensors, and a wind speed sensor.