Design of yaw brake system for horizontal axis wind turbine generator

The present study discussed pertinent design parameters used in designing the yaw brake system of horizontal axis wind turbine. The hydraulic power unit of yaw brake system should be designed properly to control the yaw brake during yaw movement of nacelle and to activate the brake calipers when necessary during turbine operation and maintenance work. System design requirements of hydraulic power unit are presented according to IEC 61400-1 and GL Wind guidelines. To understand the arrangement of hydraulic power unit components, three (3) different hydraulic circuit models for yaw brake systems were evaluated. Each configuration of hydraulic power unit for yaw brake system was analyzed by determining the pump performance characteristics using HyPneu software. The simulation results identified hydraulic circuit model with the most controlled system pressure environment, with properly regulated flow rate and best pumping efficiency of 72.03%.