Speaker
Dr. Xiaodong Liang, Assistant Professor, Department of Electrical and Computer Engineering, Memorial University of Newfoundland
Topic
Dynamic Load Modeling Method
Abstract
Power system planning, operation and control rely heavily on simulation models. Among all components modeling, load representation remains the least accurate due to large number of diverse load in the system and their time variant stochastic nature. The appearance of new non-conventional power electronic load and intermittent distributed generation add more complication and challenge to load modeling. Accurate dynamic load model is very important for power system stability studies, inaccurate load model may result in actual system collapse or separation.
In bulk power system studies, a load generally refers to the collective power demand at a substation – a portion of the system that is not explicitly represented in a system model, but rather is treated as if it is a single power-consuming device connected to a bus in the system model. The issues faced by power industry include: how to determine load composition by sectors (commercial, industrial, and residential); how much influence power electronic devices have on grid stability; and how to identify critical parameters of load models using traditional measurement-based or component-based approach.
To address some of these issues, a new concept, the template-based modeling technique, is developed for large industrial and commercial facilities in this study. These facilities typically draw large amount of power and have complex dynamic response to system disturbances. Traditional load modeling approaches such as those based on load composition or site measurement are not adequate to produce dynamic models for these facilities. The template-based load modeling technique requires minimal user input and can be implemented in a database program. Oil refinery facilities are used as an example to illustrate the proposed technique. Variable frequency drives (VFDs) are widely used in industrial facilities, their dynamic model, however, is not available for power system dynamic studies. The dynamic load model for VFD-motor systems is developed as part of the load modeling work for industrial facilities. Finally, a new generic composite load model structure for industrial facilities is proposed, which consists of four main loads, an induction motor, a synchronous motor, a motor drive system, and a static load.
Biography
Dr. Xiaodong Liang is an assistant professor with Memorial University of Newfoundland in St. John’s, Canada. She obtained her Ph.D. degree from the University of Alberta, Edmonton, Canada in 2013.
From 1995 to 1999, she served as a lecturer at Northeastern University, Shenyang, China. In October 2001, she joined Schlumberger in Edmonton, Canada, and in 2009 was promoted to be a Principal Power Systems Engineer with this large oil service company. After serving Schlumberger for almost 12 years, she joined Washington State University in Vancouver, Washington, United States in August 2013. From August 2013 to May 2015, she was a tenure-track assistant professor at Washington State University. In July 2015, she joined Memorial University of Newfoundland.
Dr. Liang is the author/co-author of 80 refereed journal and conference publications, and has 5 patent applications. During the work with Schlumberger, she wrote more than 100 engineering reports to industrial clients worldwide. Her research interests include power system dynamics, renewable energy integration, and electric machines.
Dr. Liang is a registered professional engineer in the provinces of Alberta and Newfoundland and Labrador, Canada. She is a Senior Member of IEEE (since 2009). She serves as an Associate Editor for IEEE Transactions on Industry Applications and IEEE Industry Application Magazine (since 2013).