Measurement uncertainty estimation of a novel torque transducer for wind turbine test benches

Abstract

This paper covers the measurement uncertainty estimation of a novel 5 MN•m torque transducer based on the Force-Lever principle for wind turbine test benches. The motivation of this novel transducer is to provide a satisfying accuracy in torque measurement above 1.1 MNm. Therefore the estimation of the measurement uncertainty is significant to evaluate the design. At the beginning the design is shortly introduced. Afterwards, the design is investigated under operational conditions (e.g. torque, gravity, rotational speed and multiaxial loads) by using FE simulations to determine the deformation and the parasitic loads. Finally, the measurement uncertainty is determined based on these FE simulations according to the type B evaluation of the GUM [1], including metrological aspects (e. g. linearity deviation and hysteresis). Additionally, the share in the measurement uncertainty is examined to indicate further starting points for improvements of the design. It can be shown that the novel torque transducer provides a high potential to significantly improve the measurement uncertainty in the MNm range towards existing torque measurement methods.