This page has only limited features, please log in for full access.
This study investigates the effect of uncertainty characteristics of renewable energy resources on the flexibility of a power system. The more renewable energy resources introduced, the greater the imbalance between load and generation. Securing the flexibility of the system is becoming important to manage this situation. The degree of flexibility cannot be independent of the uncertainty of the power system. However, most existing studies on flexibility have not explicitly considered the effects of uncertainty characteristics. Therefore, this study proposes a method to quantitatively analyze the effect of uncertainty characteristics on power system flexibility. Here, the uncertainties of the power system indicate the net load forecast error, which can be represented as a probability distribution. Of the characteristics of the net load forecast error, skewness and kurtosis were considered. The net load forecast error was modeled with a Pearson distribution, which has been widely used to generate the probability density function with skewness and kurtosis. Scenarios for the forecast net load, skewness, and kurtosis were generated, and their effects on flexibility were evaluated. The simulation results for the scenarios based on a modified IEEE-RTS-96 revealed that skewness is more effective than kurtosis. The proposed method can help system operators to efficiently respond to changes in the uncertainty characteristics of renewable energy resources.
Changgi Min. Investigating the Effect of Uncertainty Characteristics of Renewable Energy Resources on Power System Flexibility. Applied Sciences 2021, 11, 5381 .
AMA StyleChanggi Min. Investigating the Effect of Uncertainty Characteristics of Renewable Energy Resources on Power System Flexibility. Applied Sciences. 2021; 11 (12):5381.
Chicago/Turabian StyleChanggi Min. 2021. "Investigating the Effect of Uncertainty Characteristics of Renewable Energy Resources on Power System Flexibility." Applied Sciences 11, no. 12: 5381.
This study proposes a method to evaluate the impact of transmission congestion on the flexibility of a power system, based on the ramping capability shortage expectation (RSE). Here, flexibility refers to the ability to retain a power balance in response to changes in the net load. The flexibility issue arises due to the extensive integration of renewable energy resources; specifically, the higher the degree of integration, and the greater the variability and uncertainty in the power system. Flexibility is further limited by the net transfer capacity (NTC) of transmission lines. Here, we propose a method capable of capturing the extent to which transmission congestion affects the power system, to identify transmission reinforcement options for improved flexibility. In Korea, transmission congestion occurs frequently in regions to the north and southeast. A case study for a Korean power system in 2030 was conducted. Simulation results showed that the impact of transmission reinforcement in flexibility tends to be proportional to the NTC and is greater when the penetration level is low.
Changgi Min. Impact Analysis of Transmission Congestion on Power System Flexibility in Korea. Energies 2020, 13, 2191 .
AMA StyleChanggi Min. Impact Analysis of Transmission Congestion on Power System Flexibility in Korea. Energies. 2020; 13 (9):2191.
Chicago/Turabian StyleChanggi Min. 2020. "Impact Analysis of Transmission Congestion on Power System Flexibility in Korea." Energies 13, no. 9: 2191.
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.
Chang-Gi Min. Analyzing the Impact of Variability and Uncertainty on Power System Flexibility. Applied Sciences 2019, 9, 561 .
AMA StyleChang-Gi Min. Analyzing the Impact of Variability and Uncertainty on Power System Flexibility. Applied Sciences. 2019; 9 (3):561.
Chicago/Turabian StyleChang-Gi Min. 2019. "Analyzing the Impact of Variability and Uncertainty on Power System Flexibility." Applied Sciences 9, no. 3: 561.