Engineering topics

Dagle, Jeffery E

Publications and source records attributed to Dagle, Jeffery E.

5 records

DOE OSTI2012

The Characteristic Ellipsoid Methodology and Its Application in Power Systems

The characteristic ellipsoid (CELL) method to monitor dynamic behaviors of a power system is proposed. Multidimensional minimum-volume-enclosing characteristic ellipsoids are built using synchronized phasor measurements. System dynamic behaviors are identified by tracking the change rate of the CELL’s characteristic indices. Decision tree techniques are used to link the CELL’s characteristic indices and the system’s dynamic behaviors and to determine types, locations and related information about the dynamic behaviors. The knowledge base of representative transient events is created by offline simulations based on the full Western Electric Coordinating Council (WECC) model. Two case studies demonstrate that the CELL method combined with the decision trees can detect transient events and their features with good accuracy.

Characteristic ellipsoid, decision tree, event det↗

DOE OSTI2011

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices

Electrical power distribution control methods, electrical energy demand monitoring methods, and power management devices are described. In one aspect, an electrical power distribution control method includes providing electrical energy from an electrical power distribution system, applying the electrical energy to a load, providing a plurality of different values for a threshold at a plurality of moments in time and corresponding to an electrical characteristic of the electrical energy, and adjusting an amount of the electrical energy applied to the load responsive to an electrical characteristic of the electrical energy triggering one of the values of the threshold at the respective moment in time.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗

DOE OSTI2011

Event Classification and Identification Based on the Characteristic Ellipsoid of Phasor Measurement

In this paper, a method to classify and identify power system events based on the characteristic ellipsoid of phasor measurement is presented. The decision tree technique is used to perform the event classification and identification. Event types, event locations and clearance times are identified by decision trees based on the indices of the characteristic ellipsoid. A sufficiently large number of transient events were simulated on the New England 10-machine 39-bus system based on different system configurations. Transient simulations taking into account different event types, clearance times and various locations are conducted to simulate phasor measurement. Bus voltage magnitudes and recorded reactive and active power flows are used to build the characteristic ellipsoid. The volume, eccentricity, center and projection of the longest axis in the parameter space coordinates of the characteristic ellipsoids are used to classify and identify events. Results demonstrate that the characteristic ellipsoid and the decision tree are capable to detect the event type, location, and clearance time with very high accuracy.

24 POWER TRANSMISSION AND DISTRIBUTION↗

DOE OSTI2011

Defining resilience within a risk-informed assessment framework

The concept of resilience is the subject of considerable discussion in academic, business, and governmental circles. The United States Department of Homeland Security for one has emphasised the need to consider resilience in safeguarding critical infrastructure and key resources. The concept of resilience is complex, multidimensional, and defined differently by different stakeholders. The authors contend that there is a benefit in moving from discussing resilience as an abstraction to defining resilience as a measurable characteristic of a system. This paper proposes defining resilience measures using elements of a traditional risk assessment framework to help clarify the concept of resilience and as a way to provide non-traditional risk information. The authors show various, diverse dimensions of resilience can be quantitatively defined in a common risk assessment framework based on the concept of loss of service. This allows the comparison of options for improving the resilience of infrastructure and presents a means to perform cost-benefit analysis. This paper discusses definitions and key aspects of resilience, presents equations for the risk of loss of infrastructure function that incorporate four key aspects of resilience that could prevent or mitigate that loss, describes proposed resilience factor definitions based on those risk impacts, and provides an example that illustrates how resilience factors would be calculated using a hypothetical scenario.

99 GENERAL AND MISCELLANEOUS↗

DOE OSTI2011

Deriving Optimal Operational Rules for Mitigating Inter-area Oscillations

This paper introduces a new method to mitigate inter-area oscillations of a large scale interconnected power system by means of generation re-dispatch. The optimal operational control procedures are derived as the shortest distance from the current operating condition to a desired damping ratio of the oscillation mode by adjusting generator outputs. A sensitivity based method is used to select the most effective generators for generation re-dispatch and decision tree is trained to approximate the security boundary in a space characterized by the selected generators. The optimal operational rules can be found by solving an optimization problem where the boundary constraints are provided by the decision tree rules. This method is tested on a Western Electricity Coordinating Council (WECC) 179-bus simplified network model and simulation results have demonstrated the proof of concept and shown promising application in real time operation.

24 POWER TRANSMISSION AND DISTRIBUTION↗