Articles for mei 2021

KD 439 reviewed

A new chapter 6 has been added to report KD 439 about the pendulum safety system with a torsion spring. In this chapter the use of the VIRYA-10 rotor is described. I expect that this pendulum safety system can be used up to a rotor diameter of about 20 m but for such a large rotor diameter it might be better to keep the rotor in the wind by a wind servo in stead of by a double vane.

KD 718 added

Report KD 718 has been added to my website at the menu KD-reports. The title of this report is: “Ideas about a 16-pole, 3-phase permanent magnet generator using the housing and winding of a 4-pole asynchronous motor frame size 100”.

This report describes a way how to modify a standard 4-pole, 3-phase asynchronous motor such that it can be used as a PM-generator for a wind turbine for 24 V or 48 V battery charging. Manufacture of the new armature is rather easy as the magnet grooves are wide and shallow. The magnet costs are low as only a rather small magnet volume is used. Mechanically the armature has sixteen poles but physically it has four poles and therefore it can work together with the standard winding of a 4-pole motor. The armature pole angle is 2.5┬░ larger than twice the stator pole angle and the fluctuation of the sticking torque is therefore almost flattened. A reference to KD 718 is also incorporated in KD 341.

A new chapter 5 has been added to KD 718. The title of this chapter is: “Checking of the strength of the glue in between magnets and armature”.