Integration of Motor-Assisted Planetary CVT Systems for Wind Turbines under Variable Wind Conditions

Abstract

This paper presents a novel continuously variable transmission (CVT) system for wind turbine applications, com­bining a planetary gearbox with a motor-assisted control mecha­nism. The proposed architecture enables real-time adjustment of the transmission ratio by dynamically regulating the ring gear using a synchronous electric motor. A detailed mathematical model is developed to describe the gear kinematics and torque distribution, followed by a complete Simulink implementation that captures the electromechanical interactions between the turbine input, planetary gear system, and motor controller. Sim­ulations were conducted for three motor speed scenarios (600, 1200, and 1800 rpm), representing low, medium, and high wind conditions. The results confirm the system’s ability to stabilize torque, adapt output speed, and respond effectively to dynamic changes in input conditions. The integration of electric motor control within a planetary CVT system offers improved flexibility, efficiency, and control precision for variable-speed wind turbine applications.