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Increasing the proportion of carbon-free power sources, such as renewable energy, is essential for transitioning to a zero-carbon power system. However, when the rate of grid expansion and flexibility cannot match the rate of renewable energy increase, surplus energy is the result. Surplus energy can be discarded through curtailment or stored and utilized when required. The optimal equipment configuration of the storage system should be determined based on the surplus energy characteristics. This study proposes an optimal energy storage mix configuration method by considering long-term forecasts of surplus energy in the South Korean renewable energy supply and power grid expansion plan. The surplus energy by time slot is comprehensively analyzed considering renewable energy power output, power demand, and power system operation constraints. We calculate the required power and energy of storage devices. Furthermore, we construct a long-term optimal energy storage mix using surplus energy generation patterns and technical and economical characteristics of storage technologies. The total cost minimization was considered as the objective function, comprising three elements: initial construction, equipment replacement, and loss costs for charging and discharging. We propose a time sequence analysis (TSA) method that enables chronological analysis from the starting year to the final target year. The TSA method provides an energy storage mix configuration roadmap that can utilize surplus energy for various years over the entire period, considering the annual increase in surplus energy and commercialization timing of each storage technology. We compare the difference between our proposed TSA method and the method that analyzes only the final target year to validate the superiority of this methodology. [ABSTRACT FROM AUTHOR]

This study examines the effectiveness of government-supported incubator programmes in China. Findings highlight the importance of private-sector involvement in the incubators' governing body. Previous literature acknowledges the importance of government intervention in the entrepreneurial incubation process to overcome innovation market failure. However, factors that potentially influence the effectiveness of government-supported incubators have not been explored. Using surveys and follow-up interviews with managers of tenant venture firms, as well as administrators of four sampled incubators in Shanghai and Chongqing, we find that government-supported business incubators effectively provide physical infrastructure, general resources such as administrative support, and access to university resources. Except for the incubator that has been managed by business professionals, government-supported incubators are found to be rather ineffective in offering counselling, external private financing, and networking services to incubated tenant firms, which suggests that government agencies and officials lack business and technological expertise. The implications of the effectiveness of government-driven incubator programmes and avenues for future research are discussed. [ABSTRACT FROM AUTHOR]

In this study, we draw upon literature in technology and innovation management to theorise about how process improvement efforts in organisations can drive the exploratory activity that is generally associated with more radical forms of innovation. We develop a set of propositions on how process improvement efforts might directly and indirectly drive exploration and more radical forms of organisational innovation. These propositions are organised into four categories: (1) ‘Direct’ – how exploratory forms of process improvement can directly drive innovativeness; (2) ‘Resource Capacity’ – how process improvement can increase the resource capacity that drives innovativeness; (3) ‘Knowledge’ – how process improvement efforts can strengthen knowledge resources that drive innovativeness; and (4) ‘Management Vision’ – how process improvement efforts can influence the managerial vision that moderates the effect of process improvement efforts on innovativeness. [ABSTRACT FROM AUTHOR]

With growing interest in sustainability and net-zero emissions, there has been a global trend to integrate wind power into energy grids. However, challenges such as the intermittency of wind energy remain, which leads to a significant need for accurate wind-power forecasting. Therefore, this study focuses on creating a wind-power generation-forecasting model using a machine-learning algorithm. In this study, we used the gradient-boosting machine (GBM) algorithm to build a wind-power forecasting model. Time-series data with a 15 min interval from Jeju's wind farms were applied to the model as input data. The short-term forecasting model trained by the same month with the test set turns out to have the best performance, with an NMAE value of 5.15%. Furthermore, the forecasting results were applied to Jeju's power system to carry out a grid-security analysis. The improved accuracy of wind-power forecasting and its impact on the security of electrical grids in this study potentially contributes to greater integration of wind energy. [ABSTRACT FROM AUTHOR]

Recently, the number of electric-power facilities, including high-voltage direct current (HVDC) and flexible AC current transmission system (FACTS), has rapidly increased, owing to restrictions regarding the expansion of existing AC networks. Traditionally, a final site acceptance test (SAT) is conducted following controller performance verification in a factory acceptance test (FAT), based on an equivalent small network or voltage sources. Furthermore, several standards and guidelines related to the FAT and SAT of HVDC and FACTS have been published. Meanwhile, as the number of power electronic devices and the complexity of power systems increase, controller performance tests reflecting the wide area dynamic characteristics and control operation of adjacent devices should be required. However, a wide-area dynamic performance test (DPT) requires a large-scale real-time simulator and high-level operational technology. Owing to these difficulties, the definition, standard, procedure, and test protocol of hardware-in-the-loop simulation (HILS)-DPT, based on a large-scale power system, have not yet been established systematically, and only a few applications have been reported. This study aims to establish and propose procedures, a test protocol, and a methodology of HILS-DPT and large-scale power system modeling for testing. To this end, a case study was conducted to demonstrate the necessity of the DPT procedures and methodologies for the static VAR compensator controller installed at the Shin-Jecheon substation, an ongoing project undertaken the by Korea Electric Power Corporation, as of 2019. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to introduce, examine, and evaluate the industrial experiences and effectiveness of a Thyristor Controlled Series Compensator (TCSC) replica controller installed in Korea in 2019 through a review of its configuration, test platform, and practical application, and further to propose operational guidelines for replica controllers. Four representative practical cases were conducted: a Dynamic Performance Test (DPT) under a sufficiently large-scale power system prior to the Site Acceptance Test (SAT), pre-verification for on-site controller modification during operation stage, parameter tuning to mitigate the control interaction, and time domain simulation for Sub-Synchronous Torsional Interaction (SSTI). None of these four cases can be performed in a Factory Acceptance Test (FAT) or on-site. Therefore, TCSC control performance was accurately verified under the entire Korean power system based on a large-scale real-time simulator, which demonstrated its effectiveness as a powerful tool for operations including multiple power electronics devices. Our review herein of these four practical cases is expected to show the usefulness of replica controllers, to demonstrate their strength to deal with practical field events, and to contribute to the further expansion of the application area from a perspective of electric utility. [ABSTRACT FROM AUTHOR]

This paper develops a computationally efficient method to bound the impact of multiple uncertain parameters in a dynamic load model. Load model trajectory sensitivity is first conducted on regional dynamics only (e.g., a large industrial load bus and its model for adequately representing the bus voltage dynamics) to identify critical and correlated load parameters. Systemwide trajectory sensitivity on the entire power system model is then evaluated for this reduced set of parameters, and finally, the impact of multiple uncertain parameters on the representation of power system dynamics is bounded. To reinforce this reasoning, we elaborate on the conceptual meaning of the load model trajectory sensitivity, its implication, and its applicability to the entire power grid analysis. This research also develops a fluctuation index of trajectory sensitivity to effectively rank and select the model parameters based on the impact of their perturbations on the system's dynamic performance. Case studies for the Korean power system demonstrate the validity and efficacy of the developed methods for adequately bounding the uncertainty impacts with reference to the comprehensive time-domain dynamic simulation approach. [ABSTRACT FROM AUTHOR]

This paper presents the hardware-in-the-loop simulation for dynamic performance test (HILS-DPT) of power electronic equipment replicas using a real-time hybrid simulator (RTHS). The authors developed the procedure of HILS-DPT, and as an actual case example, the results of HILS-DPT of Static VAR Compensator (SVC) replica using RTHS is presented. RTHS is a co-simulation tool that synthesizes real-time simulator (RTS) with transient stability program to perform real-time dynamic simulation of a large power system. As power electronics applications have been increasing, the electric utilities have performed HILS-DPT of the power electronics equipment to validate the performance and investigate interactions. Because inspection tests are limited in their ability to validate its impact on the power system during various contingencies, all power electronics equipment newly installed in the Korean power system should take HILS-DPT using large-scale RTS with replicas since 2018. Although large-scaled RTS offers an accuracy improvement, it requires lots of hardware resources, time, and effort to model and simulate the equipment and power systems. Therefore, the authors performed SVC HILS-DPT using RTHS, and the result of the first practical application of RTHS present feasibility comparing the result of HILS-DPT using large-scale RTS. The authors will discuss the test results and share lessons learned from the industrial experience of HILS-DPT using RTHS. [ABSTRACT FROM AUTHOR]