Analyzing the Impact of Variability and Uncertainty on Power System Flexibility

Abstract

Featured Application: This study presents a method for separating the variability and uncertainty in a power system, and determining which is more influential in terms of flexibility, based on the flexibility index, named the ramping capability shortage probability (RSP). A process of scenario generation and sensitivity analysis is also proposed, and applied to a modified IEEE-RTS-96. The proposed method can evaluate the individual effect of variability and uncertainty and effectively provide the system operator with information that will enable more efficient operation and planning of a power system. Abstract:This study investigates the impact of variability and uncertainty on the flexibility of a power system. The variability and uncertainty make it harder to maintain the balance between load and generation. However, most existing studies on flexibility evaluation have not distinguished between the effects of variability and uncertainty. The countermeasures to address variability and uncertainty differ; thus, applying strategies individually tailored to variability and uncertainty is helpful for more efficient operation and planning of a power system. The first contribution of this study is in separating the variability and uncertainty, and determining which is more influential in terms of flexibility in specific system situations. A flexibility index, named the ramping capability shortage probability (RSP), is used to quantify the extent to which the variability and uncertainty affect the flexibility. The second contribution is to generate various scenarios for variability and uncertainty based on a modified IEEE-RTS-96, to evaluate the flexibility. The penetration level of renewable energy resources is kept the same in each scenario. The results of a sensitivity analysis show that variability is more effective than uncertainty for high and medium net loads.

Weather biased optimal delta model for short‐term load forecast

“…Another perspective used to analyse the performance is by visualising the uncertainties across actual demand and forecast computed using the proposed model, and then comparing it with the output of benchmark GAM model. For this purpose, the aspects chosen were standard deviation ( σ ) and skewness (SK p ) [42, 43]. Fig.…”

Joint Operation of Renewable Energy and Battery Switch Station Considering the Benefits of Different Subjects

“…, N t . Furthermore, the RE company's revenue can be calculated by Equation (1). The backward induction method can be solved by genetic algorithm, where its objective function is maximizing the revenue of the RE company and the decision variables are the charge/discharge price in different time periods.…”

“…With the rapid development of renewable energy (RE), its uncontrollability and volatility have caused a series of problems to the grid [1][2][3][4]. Cooperation with controllable resources to enhance the controllability of RE has become a consensus [5][6][7].…”

Investigating the Effect of Uncertainty Characteristics of Renewable Energy Resources on Power System Flexibility

“…Along with these policy and institutional efforts, one of the essentials in introducing massive renewable energy resources (RERs) is to enhance the flexibility of power systems, although comprehensive strategies considering the energy sector coupled with using technologies such as power to gas (P2G) and power to heat (P2H) equally count [6]. The large penetration of RER into the power system is likely to increase the volatility and uncertainty of the net load, i.e., the load minus the output of the RER [7]. A growing amount of variable generation, such as wind and photovoltaic (PV) power plants, requires more flexibility, where flexibility is defined as the ability of a power system to respond to the change in net load [8].…”