Analysis of dynamics of fluid power drive‐trains for variable speed wind turbines: parameter study

Abstract

In the pursuit of making wind energy technology more economically attractive, fluid power technology for the transmission of wind energy is being developed by several parties all over the world. This study presents a dynamic model of a fluid power transmission for the variable speed wind turbines and shows a parametric study on the dynamic behaviour below the rated wind speed. A pressure control strategy is proposed to achieve a variable speed operation of the rotor while using a fixed speed generator. The rotor of a five megawatt reference turbine is used to perform the time domain simulations. Different values of the hydraulic line length and transmission efficiency are considered for the same wind conditions and the results are compared with the response of the reference gearbox drive train. The results show that the amount of oil in the hydraulic drivetrain has an important influence on the first natural frequency of the transmission and the pipeline dynamics become more relevant for the longer transmission lines. Lowering the volumetric efficiency of the hydraulic motor leads to an additional damping of the pressure fluctuation, however, its influence is minor and unlikely to be advantageous when compared with the power loss.

Simulation of an offshore wind farm using fluid power for centralized electricity generation

“…1. This paper continues with previous work (Jarquin Laguna et al, 2014;Jarquin Laguna, 2015) in an effort to asses the tradeoffs implied by the proposed hydraulic concept. To this aim, time domain simulations are used to evaluate the performance and operational parameters of individual turbines coupled to a common hydraulic network for a hypothetical wind farm with 5 centralized electricity generation.…”

Maximum Power Generation Control of a Hybrid Wind Turbine Transmission System Based on H∞ Loop-Shaping Approach

“…The flow response, angular velocity, and pressure of the system obtained from the mathematical model were compared with experiment test results to evaluate the modelling accuracy. In [10], a dynamic model and a parametric study on the dynamic behavior of a hydraulic wind turbine were presented. A pressure control strategy was proposed to drive a fixed speed generator.…”

Power Generation Control of a Monopile Hydrostatic Wind Turbine Using an <inline-formula> <tex-math notation="LaTeX">$\mathcal{H}_{\infty}$ </tex-math> </inline-formula> Loop-Shaping Torque Controller and an LPV Pitch Controller

“…In the present paper, we consider the former configuration, which has less operation & maintenance costs [1]. Several papers discussed the influences of different HST configurations on the turbine responses [1], [6].…”