Hugg Piggot
How to build a
WIND TURBINE
Axial flux alternator windmill plans
8 foot and 4 foot diameter machines
© Hugh Piggott -May 2003
How to build a wind generator - the axial flux alternator windmill plans - May 2003 version © Hugh Piggott
the results are quick for a one-off product. Moulded fibreglass blades are usually better for batch production.
Wooden blades will last for many years.
Introduction
Blades
These plans describe how to build two sizes of machine.
The diameter of the larger wind-rotor is 8 feet [2.4 m].
The smaller machine has 4' diameter [1.2 m].
The diameter is the width of the circular area swept by the blades.
page 2
DIAMETER
Furling system
The plans include a description of how to construct a furling tail for the larger machine. This tail prevents overload in high winds. This type of furling system has been in use on Scoraig for decades and has passed the test of time.
Units
The energy produced by wind turbines depends on the swept area more than it does on the alternator maximum output.
Alternator
The plans describe how to build a permanent magnet alternator. The alternator can be wired for 12, 24 or 48-volt battery charging. Essentially this choice only affects the size of wire and the number of turns per coil. But the tower wiring for the 12-volt version will be much heavier than the others. And the stator for the small machine is different in thickness.
The alternator design is integrated into a simple tower-top mounting arrangement (called a 'yaw bearing'). A tail vane faces the turbine into the wind. A built in rectifier converts the electrical output to DC, ready to connect to a battery. Small wind turbines need low speed alternators. Low speed usually also means low power. The large machine alternator is exceptionally powerful because it contains 24 large neodymium magnets. The power/speed curve for a very similar design is shown below. Maximum output is about 500 watts under normal
WIND TURBINE
Axial flux alternator windmill plans
8 foot and 4 foot diameter machines
© Hugh Piggott -May 2003
How to build a wind generator - the axial flux alternator windmill plans - May 2003 version © Hugh Piggott
the results are quick for a one-off product. Moulded fibreglass blades are usually better for batch production.
Wooden blades will last for many years.
Introduction
Blades
These plans describe how to build two sizes of machine.
The diameter of the larger wind-rotor is 8 feet [2.4 m].
The smaller machine has 4' diameter [1.2 m].
The diameter is the width of the circular area swept by the blades.
page 2
DIAMETER
Furling system
The plans include a description of how to construct a furling tail for the larger machine. This tail prevents overload in high winds. This type of furling system has been in use on Scoraig for decades and has passed the test of time.
Units
The energy produced by wind turbines depends on the swept area more than it does on the alternator maximum output.
Alternator
The plans describe how to build a permanent magnet alternator. The alternator can be wired for 12, 24 or 48-volt battery charging. Essentially this choice only affects the size of wire and the number of turns per coil. But the tower wiring for the 12-volt version will be much heavier than the others. And the stator for the small machine is different in thickness.
The alternator design is integrated into a simple tower-top mounting arrangement (called a 'yaw bearing'). A tail vane faces the turbine into the wind. A built in rectifier converts the electrical output to DC, ready to connect to a battery. Small wind turbines need low speed alternators. Low speed usually also means low power. The large machine alternator is exceptionally powerful because it contains 24 large neodymium magnets. The power/speed curve for a very similar design is shown below. Maximum output is about 500 watts under normal