A framework for the analysis of voltage collapse in electric power systems

Thesis/Dissertation · Sun Jan 01 04:00:00 EST 1989

OSTI ID:6156840

Mercede, F J

The phenomenon of voltage collapse in a power system is manifested as a progressive decline (i.e., sagging) in bus voltages, notably load bus voltages, over a relatively long time frame (i.e., seconds to minutes). At present, the voltage collapse problem is not fully understood; which makes its prevention, assessment and control difficult. Further complicating this problem is the confusion over whether voltage collapse is steady-state or dynamic in nature. The main contribution of this thesis is the formulation of a decision support framework to evaluate the accuracy of Performance Indices (PI's) used to assess voltage instability phenomena, such as voltage collapse, in electric power systems. It is shown that many of the criteria proposed in the literature to assess voltage stability can be rewritten in terms of scalar PI's and corresponding threshold values of the PI's. Based on this framework, criteria to assess voltage stability are reformulated as decision rules; so that, the misclassification errors incurred in using the criteria can be expressed in terms of (i) the probability of missing a voltage unstable event and (ii) the probability of false alarm. It is shown that the key to quantifying these misclassification errors are the definitions and characterizations of a Voltage Stability (VS) Region, which is based on the power system model and signifies the universal set of possible impacts on the system, and an Approximate Voltage Stability (AVS) Region, which is defined by the voltage stability criterion. Moreover, based on this framework, an optimization problem is formulated whose solution provides an accurate criterion to predict static mechanisms of voltage instability which satisfies a given trade-off in the number of misses and false alarms by the operator.

• Research Organization: Drexel Univ., Philadelphia, PA (USA)
• OSTI ID: 6156840
• Country of Publication: United States
• Language: English

Related Subjects

24 POWER TRANSMISSION AND DISTRIBUTION
240100* -- Power Systems-- (1990-)
CONTROL
DECISION MAKING
ELECTRIC POTENTIAL
ELECTRIC POWER
ENERGY SYSTEMS
EVALUATION
OPERATION
OPTIMIZATION
PERFORMANCE
POWER
POWER SYSTEMS
PROBABILITY
STABILITY
SYSTEMS ANALYSIS
TIME DEPENDENCE
VOLTAGE DROP