A dynamic power system model cannot perfectly predict the behaviour of a physical power system. Model validation tries to answer the question whether the model predicts the behaviour of the physical system sufficiently. This study evaluates if and how a dynamic power system model of the Dutch power grid can be validated using PMU measurements. For this, two approaches to validation of dynamic power system models are compared. They are validation using System Wide Simulation and validation using Hybrid Dynamic Simulation. Both approaches use measurements of disturbances in the power system as a basis for the comparison of the measured and the simulated behaviour of the system. With System Wide Simulation, comparison can be done using measured voltage magnitude, active power flow and reactive power flow. With Hybrid Dynamic Simulation, comparison can be done using measured active power flow and reactive power flow. Identification of model inaccuracies is limited by inaccuracies that are the result of the simulation approach. Inaccuracies are introduced by poor representation of the pre-disturbance operating conditions of the model and poor representation of the disturbance in the simulation. System Wide Simulation is more strongly affected in both cases and is therefore less accurate than Hybrid Dynamic Simulation. System Wide Simulation can be used to gain rough insight into the validity of a model. For accurate model validation and subsequent calibration however, System Wide Simulation falls short, and Hybrid Dynamic Simulation is required. Hybrid Dynamic Simulation however requires PMU measurements to be taken in specifically targeted locations.