Wind turbine

Abstract

A vertical axis wind turbine system is provided that converts wind enemy into electrical or mechanical enemy. The turbine comprises at least one turbine rotor with a plurality of curved blades for receiving head-on wind generated airflow. Shield means mountable around at least a portion of the rotor serve to protect the upstream-moving blades from head-on wind airflow and thereby reduce drag. In one embodiment, load compensation means are provided to adjust the moment of inertia of the turbine rotor. One or more of the turbine rotor blades is hollow and defines a closed volume for holding a fluid, the fluid being displaceable in use through baffle means towards or away from the vertical axis of the rotor as the rotational velocity of the rotor changes.

Description

TECHNICAL FIELD[0001]An example embodiment of the invention pertains generally to a vertical wind turbine system having wind shield means for reducing drag on the non-driving (return) blades of the turbine imposed by the oncoming wind. Another example embodiment relates to a wind turbine system with load compensation means.BACKGROUND[0002]Various wind turbines and air screws for the generation of electricity have been proposed. The present disclosure relates to a vertical axis type of air turbine, more commonly known as a “vertical” wind turbine. One difficulty with vertical rotating blades is that about half of the blades are driving the turbine at any time whereas the opposite half or “dead” blades slow the rotation down due to drag. These dead or non-driving blades are return blades trying to move upwind during part of their rotational cycle against the direction of the prevailing wind. This drag can significantly reduce the power output and energy conversion efficiency of vertic...

AI Technical Summary

Benefits of technology

The patent text describes a vertical wind turbine system with a load compensation means to reduce drag and improve energy conversion efficiency. The system also includes wind shield means to prevent drag on the non-driving blades. The technical effects of the invention include reducing drag and improving energy conversion efficiency, as well as load compensation means to prevent instability and excessive vibration.

Problems solved by technology

One difficulty with vertical rotating blades is that about half of the blades are driving the turbine at any time whereas the opposite half or “dead” blades slow the rotation down due to drag.

This drag can significantly reduce the power output and energy conversion efficiency of vertical wind turbines.

Another difficulty is that the torque on a vertical turbine blade can be compromised in that at low wind speeds it may not take much load to stop the turbine from turning while at high speeds the rotational velocity of a load-uncompensated turbine can become very high causing instability and excessive vibration.

Even at high speeds the angular momentum of an uncompensated turbine can be insufficient to maintain an even speed when load is applied.

Images