Power control for direct-driven permanent magnet wind generator system with battery storage.

Area of Science:

• Renewable Energy Systems
• Electrical Engineering
• Control Systems

Background:

• Wind generator systems (WGS) face challenges with nonlinear dynamics and energy losses in turbines and generators.
• Optimizing effective output power and turbine speed is crucial for WGS efficiency.
• Mode conversion in WGS can negatively impact battery lifetime due to power fluctuations.

Purpose of the Study:

• To construct a comprehensive loss model for wind turbines and generators.
• To optimize maximum effective output power and turbine speed.
• To develop a control strategy that minimizes battery degradation during mode conversion.

Main Methods:

• Developed a dynamic model of the nonlinear WGS, incorporating Buck converter duty.
• Employed feedback linearization to design controllers for turbine speed tracking and load power.
• Proposed a dual-mode dynamic coordination strategy utilizing an auxiliary load.

Main Results:

• Successfully optimized turbine speed and generator power tracking.
• Demonstrated significant reduction in redundant power during mode conversion.
• Validated the effectiveness of the proposed strategy on a 5 kW WGS test platform.

Conclusions:

• The developed WGS loss model and control strategy effectively optimize power output and turbine speed.
• The dual-mode dynamic coordination strategy enhances battery lifetime by mitigating mode conversion impacts.
• The approach is proven efficient for capturing generator output power.