Abstract
The risk-based assessment is a new approach to the voltage stability assessment in power systems. Under several uncertainties, the security risk of static voltage stability with the consideration of wind power can be evaluated. In this paper, we first build a probabilistic forecast model for wind power generation based on real historical data. Furthermore, we propose a new probability voltage stability approach based on Conditional Value-at-Risk (CVaR) and Quasi-Monte Carlo (QMC) simulation. The QMC simulation is used to speed up Monte Carlo (MC) simulation by improving the sampling technique. Our CVaR-based model reveals critical characteristics of static voltage stability. The distribution of the local voltage stability margin, which considers the security risk at a forecast operating time interval, is estimated to evaluate the probability voltage stability. Tested on the modified IEEE New England 39-bus system and the IEEE 118-bus system, results from the proposal are compared against the result of the conventional proposal. The effectiveness and advantages of the proposed method are demonstrated by the test results.
Highlights
With the rapid growth of power demand, modern power grids have been changing incredibly throughout the world
We provide a new voltage stability index based on Quasi-Monte Carlo (QMC) and Conditional Value-at-Risk (CVaR), which reveals important aspects of static voltage stability and is used for the online evaluation of tail risk-based security levels of wind-penetrated power systems
References [31,32,33] use the Gaussian mixture model to approximate the development for the probability density function (PDF) of wind power generation
Summary
With the rapid growth of power demand, modern power grids have been changing incredibly throughout the world. While the duck curve phenomenon represents an average net load behavior, it is the highly stochastic and spatial-temporal-dependent ramp event that presents difficult operational challenges to system operators For this reason, power system voltage stability is one of major topics of concern for secure operation of transmission networks. Reference [9] introduces a transmission line overload risk index for measuring the security level of wind integrated power systems considering the wind and load-power generation correlation. Researchers have made great efforts, these probabilistic risk-based methods are not appropriate enough for large wind power-penetrated system, because these indices cannot reflect the tail risk of the voltage static loss. We provide a new voltage stability index based on QMC and CVaR, which reveals important aspects of static voltage stability and is used for the online evaluation of tail risk-based security levels of wind-penetrated power systems.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
