Small wind turbine system

A small wind turbine electricity generation system for generating and providing electric power from a wind turbine to a power system, comprising:

• a small wind turbine for producing less than 10 kW of peak electric power, said wind turbine having a rotor that uses drag for extracting some energy from wind;
• said rotor drives a permanent magnet generator that produces generator power with a frequency that varies with the wind speed;
• a power converter that applies a load to said permanent magnet generator and converts said generator power to electric power for said power system;
• said power converter utilizes three operating regions including a low wind speed region, a medium wind speed region and a high wind speed region, wherein said power converter provides no power to said power system grid in the low wind speed region, said power converter provides power with an increasing function of the turbine rotational speed in said medium wind speed region and in said high wind speed region, said power converter provides output power by increasing the rotor operating tip speed ratio of said rotor above the tip speed ratio corresponding to the maximum power coefficient for said rotor.

A small wind turbine electricity generation system for generating and providing grid-tied AC electric power from a wind turbine to a power system grid, comprising:

• a small wind turbine for producing less than 10 kW of peak electric power, said wind turbine having a cross-wind rotor;
• said wind turbine drives a permanent magnet generator that produces generator power with a frequency that varies with the wind speed;
• a power converter that converts said generator power to said regulated AC electric power by applying a controlled load to said generator power;
• said power converter utilizes three operating regions including a low wind speed region, a medium wind speed region and a high wind speed region, wherein said power converter provides no power to said power system grid in the low wind speed region, said power converter provides power with a nonlinear increasing function of the turbine rotational speed in said medium wind speed region and in said high wind speed region, said power converter applies loads to said generator power that increase the rotor operating tip speed ratio of said rotor with increasing wind speeds.