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Glossary of Terms and Abbreviations  


Common terms and abbreviations.

HAWT Horizontal Axis Wind Turbine
VAWT Vertical Axis Wind Turbine
TSR  See_ Tip Speed Ratio
Tip Speed Ratio  The speed of the propeller tip compared to the winds speed that drives it. _ More
A of A  See_ Angle of Attack
Angle of Attack Angle between the relative wind and the prop blade _ More
Relative wind  The angle of the wind relative to a moving surface(plane of a rotating prop) _ More
Apparent wind See_ Relative Wind
Blade Angle  Angle between the blade and the plane at 90deg to the prop shaft. (also called Pitch) _ LINK
Pitch Angle between the blade and the plane at 90deg to the prop shaft. (also called Blade Angle) _ More
cct Circuit
MPP Maximum Power Point. The point in the Volt Amp ratio where maximum power is transferable.
MPPT See_ Maximum Power Point Tracking (Wind).
Maximum Power Point Tracking (Wind)  An electronic device that adjusts power levels and their Volt Amp ratio to cause the maximum transfer of wind power to the battery. MPPT(Solar) is less complex and robust.
flux Magnetic force. The path/shape of this force is the magnetic field.
PMG Permanent Magnet Generator.
pole Magnetic Pole eg. North/South also the protruding laminated finger the coils are wound around.
core  Material inside a coil to concentrate magnetic flux. Laminates of steel and air most common, ferrite rare.
cogging Magnetic attraction between the rotor magnets and the steel core laminations that resists initial starting forces.
clogging Frustrated bashing of wind generator with a Dutch wooden shoe. Actually any piece of wood or solid item at hand will do. (joke)
magic smoke The stuff that makes anything electrical work - so long as it stays within the wire. (joke)
SOC  State of Charge of a battery.
Furl  The deliberate movement of the prop from full exposure to the wind to the minimal side on/in-line exposure to make the prop slow or stop. _ More
Yaw Rotational movement about a vertical axis(mast). This movement allows the prop to point at the wind when it changes direction.
Yaw Bearing  The mast bearings that allows yaw movement.
Star  An AC generator phase wiring arrangement giving a higher voltage with lower current output for a given RPM. Also called wye in the USA.
wye See_ Star.
Delta  An AC generator phase wiring arrangement giving a lower voltage for a higher current output for a given RPM.
Inde See_ Independent. _ More
Independent  Configuration that independently rectifies each phase before series/paralleling to give final DC output. (also called Jerry Rig on the USA windmill forums). _ More
Jerry Rig  A USA forum term for independently rectifying each coil output before combining for total DC output. See_ Independent.
Swept Area  The area covered by the rotating propeller on a HAWT or rotor on a VAWT. On a VAWT the cubic nature is considered beyond the mere wind frontage area as in the case of the HAWT.
Shunt Regulator Battery protection device, fitted across a battery for turning on a dump load also across the battery and so prevent overcharging.
Controller A term often used for either a Shunt Regulator or Diversion Controller.
Diversion Controller Battery protection device fitted between the generator and the battery to divert excess power from the battery to a dump load and so prevent overcharging the battery.
Regulator See_ Shunt Regulator
EMF Electro Motive Force. The unit of measurement is the Volt.
Back EMF Braking A deliberate short circuiting of the generators output to cause maximum load and so (usually) stop it turning.
Buck Converter Electronic arrangement that converts/transforms the Volt Amp relationship of power. It reduces The Voltage and increases the current for a final reduced power due to conversion losses.
Boost Converter  Electronic arrangement that converts/transforms the Volt Amp relationship of power. It increases the Voltage and decreases the current for a final reduced power due to conversion losses.
Stall The state of a propeller when the power required (generator loading) exceeds the props driving force (derived from the wind).
MMF See_ Magnetomotive force
Magnetomotive force  Also known as magnetic potential, is the property of certain substances or phenomena that gives rise to magnetic fields. The unit of measurement is the AmpTurn (AT).
Dump Load Any load, but usually resistive, that dissipates the excess power that would otherwise overcharge a battery. Control of the dump load is by a Shunt Regulator or Diversion Controller.
VFD  See_ Variable Frequency Drive
Variable Frequency Drive Is an electronic device for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor.
Islanding  A small section of a power grid that is still 'LIVE' despite the overall grid shut down. Caused by a back-yarder's generator illegally feeding into the grid. **DEADLY** .

     

       

Special thanks to Gill for putting most of these terms together

 

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