Model Predictive Torque Control of a Wind Turbine System Test Bench in Hardware-in-the-Loop Operation

This paper presents a Model Predictive Control of the flange torque of a Wind Turbine System Test Bench drive train as the core of a Hardware-in-the-Loop simulation. A System Test Bench enables the efficient and reproducible investigation of the complex behavior of an entire Wind Turbine drive train only without the rotor and tower, as these complicate the test significantly. Instead, a motor applies the torque, yet the altered drive train setup changes its dynamic considerably. This results in unrealistic loads and thus makes the operation with the original Wind Turbine control impossible. The proposed control restores the original behavior by controlling the flange torque between the Wind Turbine and Test Bench drive train according to a reference from a Hardware-in-the-Loop simulation of the rotor. It considers the motor constraints and is robust both against deviation of its internal model and time delay. In simulation, the Model Predictive Control emulates the realistic Wind Turbine drive train dynamic perfectly in part load, though with less performance, yet still robustly, in full load due to the motor constraints. It is already implemented on a dSPACE system integrated in the System Test Bench with a research Wind Turbine. The Hardware-in-the-Loop concept itself is validated experimentally with a simpler control with less performance.