Validating measurement-based composite load model

Since the digital simulation is one of the basic tools in understanding the modern complex power systems, its veracity has direct effects on the decision making on the power system operation and control. However, the accuracy of the digital simulation is dependant heavily on the model validity. Among all the dynamic components of the power system, the load is one of the most difficult one to be modeled. The difficulty lies in the fact that the scenario when the load model is built is always different from the real situation raised by the faults. So the question naturally arises that whether the measurement-based load model could be applied in the digital simulation when analyzing different operation scenarios. And to what extent does the model keep valid? It is hard to answer these questions because the field data, which constitute the basis of the measurement-based load modeling, are limited. This paper reports our work on validating the load model via RTDS. By simulating various fault situations on a model of a real provincial power system in RTDS, we could get a great amount of data to build the model as well as research its validity. Two greatly concerned problems related to the measurement-based load model are addressed in this paper; one is the possibility of applying the load model for various fault scenarios and the other is the validity of the load model when the load composition changes. Suggestions for the measurement-based load modeling practice are also given from the model validation work.