Inertia compensation scheme of WTS considering time delay for emulating large‐inertia turbines

Abstract

Wind turbine simulators (WTSs), devised for pre-validation of control strategies for wind energy conversion system, commonly employ the inertia compensation scheme for reproducing mechanical behaviours similar to real wind turbines (WTs). However, it is found in this study that when a WT with large inertia is simulated, the time delay in command communication from control unit to motor driver, usually neglected in the existing inertia compensation scheme, results in the oscillating acceleration response and consequently leads to instability of the WTS system. As a result, the existing WTS is unable to stably simulate large-inertia WTs, which significantly limits its applicability. Hence, in this study, a linear discrete model of the inertia compensation part that considers time delay of acceleration observation and communication is developed. On the basis of this model, an improved inertia compensation scheme in which a high-order filter is introduced to eliminate the deviation of acceleration response caused by the two types of time delay is proposed. Finally, the improved inertia compensation scheme and its applicability to simulating a 600 kW WT developed by National Renewable Energy Laboratory are experimentally verified.