Application of vector-based validation measures in power-hardware-in-the-loop testing of wind turbines

Integrating renewable energy sources into power grids poses challenges for manufacturers and grid operators. Accelerated production and time-to-market phases require effective testing aligned with current standards. Conventional field testing is simple and allows testing complete power generation units (PGUs), while hardware-in-the-loop (HIL) test benches offer shorter testing periods, reproducible conditions, and greater flexibility via real-time simulations. Studies show that PGU behavior on test benches can match field behavior, usually validated by fault ride-through tests. However, when field measurements are unavailable or new testing methods are developed, the accuracy of HIL simulation concepts may be questioned. This paper proposes a method for validating power HIL (PHIL) testing using vector-based measures. Physical quantities are collected in generalized vectors, allowing the application of Euclidean vector norm and cosine similarity. Unlike methods based on symmetrical components that require filtering, the proposed vector-based approach is valid for both steady-state and transient assessments. Applying the concept to three-phase PHIL simulations in wind turbine testing, the paper discusses advantages and limitations through three example applications. It demonstrates how the method can be used to validate requirements on test equipment, compare test bench and field measurements, and evaluate PHIL simulation quality when benchmark data is unavailable.