This page has only limited features, please log in for full access.
The proliferation of renewable energy resources (RES), especially solar photovoltaic (PV) generation resources, causes overvoltage and line overloading in distribution networks. This study proposes a two-level volt–var control method based on multiple timescales. The on-load tap changer (OLTC) operates on an hourly timescale, to regulate the voltage on the secondary winding. In the 15-minutes timescale, PV-connected smart inverters and static var compensators (SVCs) are obliged to compensate the reactive power for the voltage control at the point of common coupling. In the multi-timescale voltage control framework, this study proposes a new multi-sectional volt–var curve (MSVVC) of a PV inverter. The objective of the MSVVC is to minimize the energy loss in the network, improve the voltage profile, and obtain the operational margin of other reactive power compensation devices. In the process of determining the optimal parameters of the MSVVC, stochastic modeling-based load flow analysis is utilized to consider the intermittency and uncertainty of RES generation. The effectiveness of the proposed method is verified on the IEEE 33-bus system in comparison with the conventional volt–var curve cases.
Dongwon Lee; Changhee Han; Gilsoo Jang. Stochastic Analysis-Based Volt–Var Curve of Smart Inverters for Combined Voltage Regulation in Distribution Networks. Energies 2021, 14, 2785 .
AMA StyleDongwon Lee, Changhee Han, Gilsoo Jang. Stochastic Analysis-Based Volt–Var Curve of Smart Inverters for Combined Voltage Regulation in Distribution Networks. Energies. 2021; 14 (10):2785.
Chicago/Turabian StyleDongwon Lee; Changhee Han; Gilsoo Jang. 2021. "Stochastic Analysis-Based Volt–Var Curve of Smart Inverters for Combined Voltage Regulation in Distribution Networks." Energies 14, no. 10: 2785.
Renewable generation in power systems has proved to be challenging for system operators owing to the increasing levels of penetration. The operation of power systems currently requires additional flexibility and reserves due to the intermittency and unpredictability of renewable generators. However, it is difficult to precisely predict and control the stochastic nature of renewable sources; nevertheless, its capacity continues to increase. To monitor and control renewable generators efficiently, the entire system needs to be established in a hierarchical order. This study proposed the concept of a substation that is uniquely designed for renewable interconnection. The purpose of this substation is simple: to make the renewable generators dispatchable to operators such that each group of renewable generators is sufficiently stable to be considered as conventional generators. For this purpose, methods for sizing and controlling energy storage system are proposed based on forecasts and error distributions.
Yeuntae Yoo; Seungmin Jung; Sungwoo Kang; Sungyoon Song; Jaehyeong Lee; Changhee Han; Gilsoo Jang. Dispatchable Substation for Operation and Control of Renewable Energy Resources. Applied Sciences 2020, 10, 7938 .
AMA StyleYeuntae Yoo, Seungmin Jung, Sungwoo Kang, Sungyoon Song, Jaehyeong Lee, Changhee Han, Gilsoo Jang. Dispatchable Substation for Operation and Control of Renewable Energy Resources. Applied Sciences. 2020; 10 (21):7938.
Chicago/Turabian StyleYeuntae Yoo; Seungmin Jung; Sungwoo Kang; Sungyoon Song; Jaehyeong Lee; Changhee Han; Gilsoo Jang. 2020. "Dispatchable Substation for Operation and Control of Renewable Energy Resources." Applied Sciences 10, no. 21: 7938.
This paper proposes a recurrent neural network (RNN)-based maximum frequency deviation forecasting model for power systems with high photovoltaic power (PV) penetration. The proposed RNN model extracts the nonlinear features and invariant structures exhibited in regional PV power output data and time-variable frequency data in case of contingency. To capture the regularity and random characteristics of PV power output, a probability power flow-dynamic tool (PPDT) for uncertain power system modeling has been developed. This tool considers all possible combinations of PV power generation patterns, even those with low probability, such as those caused by passing clouds. The results are verified by a comparison of various artificial intelligence methods using case studies from the South Korean power system. An online dispatch algorithm that considers the frequency constraints for a designated contingency can be implemented by using the proposed model.
Sungyoon Song; Yoongun Jung; Changhee Han; Seungmin Jung; MinHan Yoon; Gilsoo Jang. Recurrent Neural-Network-Based Maximum Frequency Deviation Prediction Using Probability Power Flow Dynamic Tool. IEEE Access 2020, 8, 182054 -182064.
AMA StyleSungyoon Song, Yoongun Jung, Changhee Han, Seungmin Jung, MinHan Yoon, Gilsoo Jang. Recurrent Neural-Network-Based Maximum Frequency Deviation Prediction Using Probability Power Flow Dynamic Tool. IEEE Access. 2020; 8 (99):182054-182064.
Chicago/Turabian StyleSungyoon Song; Yoongun Jung; Changhee Han; Seungmin Jung; MinHan Yoon; Gilsoo Jang. 2020. "Recurrent Neural-Network-Based Maximum Frequency Deviation Prediction Using Probability Power Flow Dynamic Tool." IEEE Access 8, no. 99: 182054-182064.
This study proposes an adaptive droop control strategy to be used in hybrid static synchronous compensator (STATCOM) systems. The proposed voltage-sensitivity-based adaptive droop control scheme using a hybrid STATCOM system is introduced to eliminate the possibility of interference with the other voltage regulation devices while achieving better voltage regulation without having to implement a full observation of the corresponding network. The sensitivity-analysis is performed by the voltage control of STATCOM system and the sliding-mode-control is included for control system robustness. A comparison between fixed and adaptive control methods is made through case studies of the IEEE 39-bus test system. The results were further verified through a transient simulation of the hybrid STATCOM system that considers both low and high penetration levels of inverter-based reactive power resources.
Sungyoon Song; Changhee Han; Gyu-Sub Lee; Roy A. McCann; Gilsoo Jang. Voltage-Sensitivity-Approach-Based Adaptive Droop Control Strategy of Hybrid STATCOM. IEEE Transactions on Power Systems 2020, 36, 389 -401.
AMA StyleSungyoon Song, Changhee Han, Gyu-Sub Lee, Roy A. McCann, Gilsoo Jang. Voltage-Sensitivity-Approach-Based Adaptive Droop Control Strategy of Hybrid STATCOM. IEEE Transactions on Power Systems. 2020; 36 (1):389-401.
Chicago/Turabian StyleSungyoon Song; Changhee Han; Gyu-Sub Lee; Roy A. McCann; Gilsoo Jang. 2020. "Voltage-Sensitivity-Approach-Based Adaptive Droop Control Strategy of Hybrid STATCOM." IEEE Transactions on Power Systems 36, no. 1: 389-401.
As a proportion of generation using renewable energy increases in a power system, the need for facility investment is increasing in not only the distribution system but also the transmission system. However, it is inefficient to invest in new equipment to deal with the short peak output of renewable energy generation. For this reason, this paper proposes a method for operating the grid more flexibly, through an optimal operating strategy of the direct current (DC) line at medium-voltage (MV) level, thereby delaying the facility investment in the transmission line. In order to determine the optimal operating point of the converter connected with a DC line, the swarm intelligence-based optimization technique, which can minimize multi-objective function, is used. In addition, in order to overcome the communication dependency of the centralized control, which needs to receive information about the optimal operating point computed by the system operator, this paper proposes a decentralized emergency control (DEC) method in case of a communication fault.
Changhee Han; Sungyoon Song; Juyong Kim; Gilsoo Jang. Enhancing Line Capacity Utilization in Power Transmission System Using Active MVDC Link. Energies 2019, 12, 1589 .
AMA StyleChanghee Han, Sungyoon Song, Juyong Kim, Gilsoo Jang. Enhancing Line Capacity Utilization in Power Transmission System Using Active MVDC Link. Energies. 2019; 12 (9):1589.
Chicago/Turabian StyleChanghee Han; Sungyoon Song; Juyong Kim; Gilsoo Jang. 2019. "Enhancing Line Capacity Utilization in Power Transmission System Using Active MVDC Link." Energies 12, no. 9: 1589.