Measurement-based static load modelling: case study for a medium voltage distribution feeder

The precise electrical load model under various operating conditions plays a critical role for power system analysis. A suitable load model can reflect the real condition of power system operation. This paper investigates the measurement-based static load modelling for power system analysis. For this purpose, practical measurement data, including voltage active and reactive power consumption, are used to obtain an accurate static model that represents the behaviour of electrical loads. In this paper, a method based on curve fitting and practical measurement data is proposed to select the appropriate time interval for accurate determination of load model coefficients. The study shows that a medium voltage distribution feeder can be modelled as a static load by a ZIP model whose coefficients are determined during the transformer tap changing operation. The obtained results show that the proposed method can accurately model the feeder load with the normalized root mean square error (NRMSE) during tap changes of about ۰.۲۲%, and ۰.۳۴% for active and reactive power, respectively.

Keywords:

PV curve , QV curve , ZIP load model , Curve fitting , Distribution feeder