Inertia Compensation Strategy of Wind Turbine Drivetrain Testing Facility based on Energy Flow Equivalence

Abstract

The moment inertia of the wind turbine drivetrain testing facility (WTDTF) is much smaller than that of a real wind turbine (WT). In order to simulate the slow mechanical dynamic characteristics of a real WT, an inertia compensation strategy has to be applied in WTDTF. From the perspective of energy, by analyzing and reproducing a real WT’s energy flow direction on WTDTF, this paper proposes an inertia compensation strategy based on energy flow equivalence. By adding or subtraction the electric energy input from the grid to driving side of WTDTF, this strategy is equivalent to energy storage and release in the change process of a large inertia WT’s speed. Furthermore, the influence of the delay difference between the energy input loop and the energy output loop on WTDTF is analyzed, and a strategy to reduce the time delay difference is proposed. Finally, the experimental results show that the strategy proposed in this paper can achieve the target of the hundred-fold moment inertia compensation stably and accurately.