Power sharing, peace and democracy: Any obvious relationships?

Helga Malmin Binningsbø 한국외국어대학교 국제지역연구센터 2013 International Area Studies Review Vol.16 No.1

Power sharing, mostly understood as including political opponents in a joint executive coalition government, is today a dominant approach to solving conflict. Almost as a panacea it has been introduced in numerous war-affected countries and is often recommended as a political solution to overcome deep divisions between groups. Researchers, mediators and policy-makers applaud such solutions as forward-looking, peace-strengthening and democratic. However, many have criticized power sharing and its failed ability to create peace and development in divided and conflict-ridden countries. The literature on power sharing can reach such divergent conclusions because there is no consensus on what power sharing is, what the aim of it is and how to study it. Apart from broad inclusion in joint government, the understanding of power sharing varies and recommendations to ‘share power’ give little guidance to policy-makers aiming to mitigate conflict. Therefore, this article reviews 40 years of research on power sharing by elaborating on four central aspects within the literature: (1) conceptualization; (2) domain; (3) causal mechanism; and (4) measurement. While there may be no ‘true’ power sharing or ‘truth’ about power sharing, the article concludes that it is crucial that researchers and policy-makers are clear about which type of power sharing they are discussing in specific situations. Given that power sharing is increasingly recommended and implemented in many fragile and post-conflict societies, it is important to understand what is meant by power sharing in these contexts.

An Enhanced Power Sharing Strategy for Islanded Microgrids Considering Impedance Matching for Both Real and Reactive Power

Liaoyuan Lin,Qian Guo,Zhihong Bai,Hao Ma 전력전자학회 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

There exists a strong coupling between real and reactive power owing to the complex impedances in droop based islanded microgrids (MGs). The existing virtual impedance methods consider improvements of the impedance matching for sharing of the voltage controlled power (VCP) (reactive power for Q-V droop, and real power for P-V droop), which yields a 1-DOF (degree of freedom) tunable virtual impedance. However, a weak impedance matching for sharing of the frequency controlled power (FCP) (real power for P-ω droop, and reactive power for Q-ω droop) may result in FCP overshoots and even oscillations during load transients. This in turn results in VCP oscillations due to the strong coupling. In this paper, a 2-DOF tunable adaptive virtual impedance method considering impedance matching for both real and reactive power (IM-PQ) is proposed to improve the power sharing performance of MGs. The dynamic response is promoted by suppressing the coupled power oscillations and power overshoots while realizing accurate power sharing. In addition, the proposed power sharing controller has a better parametric adaptability. The stability and dynamic performances are analyzed with a small-signal state-space model. Simulation and experimental results are presented to investigate the validity of the proposed scheme.

An Enhanced Power Sharing Strategy for Islanded Microgrids Considering Impedance Matching for Both Real and Reactive Power

Lin, Liaoyuan,Guo, Qian,Bai, Zhihong,Ma, Hao The Korean Institute of Power Electronics 2017 JOURNAL OF POWER ELECTRONICS Vol.17 No.1

There exists a strong coupling between real and reactive power owing to the complex impedances in droop based islanded microgrids (MGs). The existing virtual impedance methods consider improvements of the impedance matching for sharing of the voltage controlled power (VCP) (reactive power for Q-V droop, and real power for P-V droop), which yields a 1-DOF (degree of freedom) tunable virtual impedance. However, a weak impedance matching for sharing of the frequency controlled power (FCP) (real power for $P-{\omega}$ droop, and reactive power for $Q-{\omega}$ droop) may result in FCP overshoots and even oscillations during load transients. This in turn results in VCP oscillations due to the strong coupling. In this paper, a 2-DOF tunable adaptive virtual impedance method considering impedance matching for both real and reactive power (IM-PQ) is proposed to improve the power sharing performance of MGs. The dynamic response is promoted by suppressing the coupled power oscillations and power overshoots while realizing accurate power sharing. In addition, the proposed power sharing controller has a better parametric adaptability. The stability and dynamic performances are analyzed with a small-signal state-space model. Simulation and experimental results are presented to investigate the validity of the proposed scheme.

타지키스탄 라흐몬(Emomali Rahmon) 정권의권력 강화 방식 분석:권위주의 ‘권력공유’(Power-Sharing) 이론을 중심으로

성동기 한양대학교 아태지역연구센터 2020 중소연구 Vol.44 No.3

Rahmon of Tajikistan has maintained an authoritarian dictatorship for 26 years from 1994 to the present. However, Rahmon built the current regime by forming and strengthening power in an environment different from those of Kazakhstan's Nazarbayev, Uzbekistan’s Karimov, and Turkmenistan’s Niyazov who were the dictators of the countries around Central Asia. Unlike the president above, Rahmon was not from a clan who had dominated political power and had virtually patrons to support him. Moreover, it was difficult for Rahmon to monopolize the country’s economic interests. However, Rahmon overcame this situation and became president in 1994 and has since strengthened his power. The purpose of this study is to analyze Rahmon’s way of strengthening power which forms power and maintains a long-term dictatorship in different conditions from Nazarbayev, Karimov, and Niyazov as above. The research will be conducted with the following contents. First, the authoritarian ‘Power-Sharing’ theory will be introduced to understand Rahmon’s way of strengthening power. Second, the process of Rahmon’s power formation will be analyzed. Third, Rahmon’s process of strengthening power will be analyzed. Fourth, the characteristics of Rahmon’s way of strengthening power will be analyzed in the context of the authoritarian ‘Power-Sharing’ theory. 타지키스탄 대통령 라흐몬은 1994년부터 현재까지 26년 동안 권위주의 독재체제를 유지하고 있다. 그러나 라흐몬은 중앙아시아 주변 국가의 독재자였던 카자흐스탄의 나자르바예프, 우즈베키스탄의 카리모프, 투르크메니스탄의 니야조프와는 다른 정치적 배경과 환경에서 권력을 형성하고 강화하여 현 체제를 구축했다는 차이점을 가지고 있다. 위의 대통령들은 구소련 붕괴 이전에 이미 고르바초프의 지지를 받아서 최고 권력자의 위치에 있었고, 자신이 속한 지역파벌을 중심으로 권력을 강화시켜 나갔고, 국가의 경제적인 이권을 사실상 독점하였다는 공통점을 가지고 있었다. 반면에 라흐몬은 고르바초프와 같은 최고 권력자로부터 지지를 받지 못했고 자신이 속한 지역파벌은 기존에 정치권력을 장악한 지역파벌과 종속관계에 있는 불리한 상황에서 권력을 형성하였다. 게다가 그는 타지키스탄 내전으로 인해서 자신의 권력을 구축하고 강화해 나가는데 필요한 경제적 이권을 차지할 수도 없었다. 그러나 이러한 배경과 환경을 가졌음에도 불구하고 라흐몬은 자신의 권력을 강화시켜서 26년 동안 굳건하게 자신의 독재체제를 유지했고 최근 10월 11일 대선에서도 승리하여 자신의 권력을 2027년까지 연장하였다. 본 연구의 목적은 나자르바예프, 카리모프, 니야조프와 달리 정치적 약자로 권력을 형성한 라흐몬이 어떻게 자신을 위협하는 정치적 강자들을 제거하고 권력을 강화시켜 나갔는지 그 방식과 특징을 분석하는데 있다. 본 연구는 다음과 같은 내용으로 전개된다. 첫째, 라흐몬의 권력 강화 방식을 분석하기 위해서 스볼릭(Milan Svolik)의 권위주의 ‘권력공유’(Power-Sharing) 이론이 소개될 것이다. 둘째, 라흐몬의 권력 형성 과정이 분석될 것이다. 셋째, 라흐몬의 권력 강화 과정이 분석될 것이다. 넷째, 권위주의 ‘권력공유’ 이론을 중심으로 라흐몬의 권력 강화 방식 과정에서 나타난 특징이 분석될 것이다.

공급사슬 내의 파워유형이 정보역량에 미치는 영향: CSV 가치창출 관점

박광오 ( Park Kwang-o ),장활식 ( Chang Hwal-sik ),정대현 ( Jung Dae-hyun ) 한국정보시스템학회 2018 情報시스템硏究 Vol.27 No.3

Purpose The purpose of this study is to attempt to incorporate power theory to evaluate information capability of SCM adopters. Therefore, this study focuses on the relationship of information sharing, partnership quality, and information capacity according to the power intensity of the variables of SCM. and CSV value creation. Design/methodology/approach The questionnaire of SCM builder was conducted and 302 samples were analyzed. Based on the theoretical background of power and information capacity, we set up a structural equation model. Hypothesis testing and statistical analysis were done through AMOS and SPSS. Findings First, it shows that the compensation power among the constrained power has a positive effect on the partnership quality, and the legitimacy power has the positive influence only on the information sharing. Compulsive power, compensation, and legitimacy, which are generally restrictive powers, may reduce the quality of information sharing and partnership, but the results of this study are rather higher. Second, both non-binding power expertise and criterion have a positive effect on information sharing and partnership quality. Third, information sharing has a positive effect on partnership quality. Supporting a number of research results, it is well reflected in SCM attributes where interdependence is important. Fourth, information sharing and partnership quality have a positive effect on information capacity. Information literacy has become an essential element in modern management. Fifth, the enhancement of CSV value creation plays a role of a controlling variable to further strengthen information sharing through non - binding power attribute, expertise and conformity. In addition, the strengthening of CSV value creation has been shown to play a role as a controlling variable to further strengthen the quality of partnership through the non-binding power attribution, but expertise has been rejected.

Cooperative Power Control Scheme for a Spectrum Sharing System

Ban, Tae-Won,Jung, Bang-Chul The Korea Institute of Information and Commucation 2011 Journal of information and communication convergen Vol.9 No.6

In this paper, we investigate a power control problem which is very critical in underlay-based spectrum sharing systems. Although an underlay-based spectrum sharing system is more efficient compared to an overlay-based spectrum sharing system in terms of spectral utilization, some practical problems obstruct its commercialization. One of them is a real-time-based power adaptation of secondary transmitters. In the underlay-based spectrum sharing system, it is essential to adapt secondary user's transmit power to interference channel states to secure primary users' communication. Thus, we propose a practical power control scheme for secondary transmitters. The feedback overhead of our proposed scheme is insignificant because it requires one-bit signaling, while the optimal power control scheme requires the perfect information of channel states. In addition, the proposed scheme is robust to feedback delay. We compare the performance of the optimal and proposed schemes in terms of primary user's outage probability and secondary user's throughput. Our simulation results show that the proposed scheme is almost optimal in terms of both primary user's outage probability and secondary user's throughput when the secondary user's transmit power is low. As the secondary user's transmit power increases, the primary user's outage probability of the proposed scheme is degraded compared with the optimal scheme while the secondary user's throughput still approaches that of the optimal scheme. If the feedback delay is considered, however, the proposed scheme approaches the optimal scheme in terms of both the primary user's outage probability and secondary user's throughput regardless of the secondary user's transmit power.

The Effect of Information Sharing Impacts Distributor’s Channel Power? Mediation of Data-Driven Decision-Making and Moderation of Trust

판둥,엄금철,저우예이닝 한국생산성학회 2023 生産性論集 Vol.37 No.6

The rise of digital technology has also made supply chain management more complex, but it also provides more opportunities for information sharing. Information sharing can lead partners in different segments to better understand each other’s needs and capabilities, helping them better cope with market variations and uncertainties This paper investigates the relationship of information sharing between brands and distributors with distributor channel power after a successful brand-driven digitization reform. Furthermore, this study seeks to find out the moderating role of dealers’ data-driven decision-making and trust in the relationship between information sharing and distributors’ channel power. The data sources come from different industries in the Yangtze River Delta and Pearl River Delta regions, which are economically developed in China. The findings indicate that information sharing is positively associated with distributors’ channel power and data-driven decision-making. Trust mediates the impact of data-driven decision-making on channel power. This study provides new insights into how distributors can share information with brands to promote their channel power. It also presents suggestions for distributors on dealing with the relationship between the two during information sharing with brands. Researchers in the field of digital reform have previously overlooked the question of how information sharing enhances distributors’ channel power. This paper contributes to the information sharing and channel management literature by utilizing distributors’ data-driven decision-making and trust as moderation for analysis.

Accurate Power Sharing in Proportion for Parallel Connected Inverters by Reconstructing Inverter Output Impedance

Shengli Huang,Jianguo Luo 전력전자학회 2018 JOURNAL OF POWER ELECTRONICS Vol.18 No.6

This paper presents parallel-connected inverters to achieve accurate proportional power sharing. Due to line impedance mismatch, reactive power cannot be distributed proportionally when using the conventional P-ω and Q-E droop. In order to realize reactive proportional power sharing, the ratio of the droop coefficients should be inversely proportional to their power-sharing ratios. Meanwhile, the ratio of the line impedance should be inversely proportional to the desired power-sharing ratio, which is very difficult to be met in practice. In order to deal with this issue, a practical control strategy is presented. By measuring the PCC voltage and using the virtual impedance, the output impedance of individual inverters is reconstructed to counteract the line impedance effect. In order to guarantee system stability, a low pass filter is designed to suppress the bandwidth of the line compensation. Finally, the simulation and experimental results are given to verify the effectiveness of the proposed control strategy.

Design and Analysis of Decentralized Virtual Impedance Based Controller for Enhancing Power Sharing and Stability in an Islanded Microgrid

Prasad P. Shambhu,Parimi Alivelu M. 대한전기학회 2023 Journal of Electrical Engineering & Technology Vol.18 No.3

This paper investigates the role of a virtual impedance controller in improving the small-signal stability and power-sharing for an inverter-based islanded microgrid. The stability of microgrids is badly affected due to undamped low-frequency oscillations, which are often caused due to improper power-sharing among micro sources. The droop control approach has provided a viable solution to improve the power-sharing and hence the system’s stability. However, the droop gains suffer an inherent trade-off between power-sharing and stability, with a change in system dynamics like step load change. An increase in the droop gains improves power-sharing but causes low-frequency oscillating modes at the load terminals. It also deteriorates the micro sources voltage stability at the output terminals. This paper overcomes the trade-off faced by the droop controller with an approach of virtual impedance modeling along with voltage and current controller loops. A novel approach has been adapted by considering the virtual impedance as one state variable and investigating system stability by plotting the eigenvalue spectrum as a function of the droop coefficient. Participation factor-based sensitivity analysis for the proposed system has been carried out to measure the relative participation of corresponding state variables in respective oscillating modes. Time-domain simulation validates the role of virtual impedance in improving the damping performance and enhancing the participation of DG’s during the transient mode. It also provides an insight into the role of a virtual impedance controller in improving reactive power sharing and voltage stability.

Low-Voltage and High-Current DC Output Realized by Multiple Power Cells Based on Deadbeat and Automatic Current Sharing Control

Jinfeng Liu,Yu Zhang,Xudong Wang,Herbert Ho-Ching IU 대한전기학회 2017 Journal of Electrical Engineering & Technology Vol.12 No.4

This paper presents a synchronous generator with a distributed system of multiple parallel three-phase power cells. This generator can immediately output high DC. Each power cell comprises three-phase windings and a three-phase synchronous rectification bridge with a deadbeat control of load power feedforward, which can improve the characteristics of dynamic response and reflect the load variance in real time. Furthermore, each power cell works well independently and modularly using the method of automatic maximum current sharing. The simulation and experimental results for the distributed controller of multiple power cells demonstrate that the deadbeat control method can respond quickly and optimize the quality of the energy. Meanwhile, automatic maximum current sharing can realize the validity of current sharing among power cells.