FINAL BALANCING WOODEN WIND TURBINE BLADES

Today we have mounted the wooden blades to the steel brackets that attach them to the main rotor disc. Each blade has 6 bolts that sandwich the wooden blade between to pieces of steel. Each blade has a finish weight of between 10.6 to 11.9 pounds. When using wooden blades we find that an even number of blades is the best solution to accuracy in balancing. Each pair is closely matched to the opposing side so that the balance of the rotor can be nearly in balance before beginning the final weight correction. All the steel brackets are nearly identical at 10.9 pounds and hold the blade at a 15 degree angle to the face of the rotor. Rotation has been set to be clockwise.... not that this is important to function , but the blades face into the wind and a tail keep the blades in front of the tower, so yaw caused by the tower has no effect on our system of 6 blades. It should be noted that anything more than 3 blades is just showing off and has little effect on efficiency of wind capture. However, the number of blades has significant effect on starting torque in low winds and in overall rotational speed of design. Basically a one bladed system needs to spin the fastest while adding more blades causes the speed to decline substantially. We have designed this system to reach a lower stall speed in winds above 35 mph at which point any additional thrust is effectively converted into drag and upper speed limits are controlled more effectively than a three bladed system with a perfect pitch. Sow in lower speed winds the pitch is the maximum that can be achieved without substantial stall. As wind speed increases the pitch begins to exceed the angle for optimum drag coefficients and the speed can be controlled. During a power failure, grid tied control with a variable frequency regenerative drive, is no longer providing any resistance. Then the system spin up to the stall speed design of the blades. The next video i discuss how we go about the final balance of the blades.