Report KD 437 about the VIRYA-15 has been reviewed. The curve e = 0.75 L has been added in figure 8.

Report KD 793 about the VIRYA-3.2 is replaced by report KD 794 about the VIRYA-3.6. The title of KD 794 is: “Calculations executed for the 3-bladed rotor of the VIRYA-3.6 windmill (lambda design = 4.75, stainless steel blades) driving the PM-generator of Magnetic Innovations type 260-25 HS for 48 V battery charging” or water pumping. The reason is that it was expected that the torque level of the chosen generator allows a larger windmill rotor resulting in a maximum electrical power of about 1 kW at V = 10 m/s.

Report KD 792 about the VIRYA-4S is replaced by report KD 793 about the VIRYA-3.2. The title of KD 793 is: “Calculations executed for the 3-bladed rotor of the VIRYA-3.2 windmill (lambda design = 4.5, stainless steel blades) driving the PM-generator of Magnetic Innovations type 260-25 HS for 48 V battery charging”. The reason is that I could borrow a generator with the frame size which is used for the VIRYA-3.2 and that I have performed some measurements at this generator. The measurements are given in chapter 9 of KD 793.

At 11-3-2026, report KD 793 was completely reviewed. The rated wind speed was increased from 9 m/s up to 10 m/s. The Q-n curves for short-circuit and for 52 V star are now derived from the measurents for short-circuit as given in chapter 9.

At 12-3-2026, chapter 8 of KD 793 was extended. Apart from a winding with six coil bundles of five coils now also the option of three coil bundles of ten coils is described. This appears to be the configuration of the real winding which is shown in the photo of figure 7.

At 13-3-2026, the estimated peak torque of the generator was reduced from 95 Nm up to 75 Nm.