CEO power, government monitoring, and bank dividends

We investigate the role of CEO power and government monitoring on bank dividend policy for a sample of 109 European listed banks for the period 2005-2013. We employ three main proxies for CEO power: CEO ownership, CEO tenure, and unforced CEO turnover. We show that CEO power has a negative impact on dividend payout ratios and on performance, suggesting that entrenched CEOs do not have the incentive to increase payout ratios to discourage monitoring from minority shareholders. Stronger internal monitoring by board of directors, as proxied by larger ownership stakes of the board members, increases performance but decreases payout ratios. These findings are contrary to those from the entrenchment literature for non-financial firms. Government ownership and the presence of a government official on the board of directors of the bank, also reduces payout ratios, in line with the view that government is incentivized to favor the interest of bank creditors before the interest of minority shareholders. These results show that government regulators are mainly concerned about bank safety and this allows powerful CEOs to distribute low payouts at the expense of minority shareholders.

Reaaliaikaisen PMU-mittaustiedon hyödyntäminen voimajärjestelmän valvonnassa

Tämä työ on tehty Fingrid Oyj:lle. Työn tavoitteena oli tutkia, miten reaaliaikaista PMU-mittaustietoa voidaan hyödyntää voimajärjestelmän valvonnassa. Voimajärjestelmän dynaamisia ilmiöitä ovat jännite- ja kulmastabiilius. Työssä tutkittiin voimajärjestelmän kulmastabiiliutta PSS/E-ohjelmalla simuloitujen mittaustulosten perusteella. Fouriermuunnoksen tulokset osoittavat, että huonoiten vaimeneva taajuuskomponentti on 0,3 Hz taajuus. Lisäksi tiedetään, että huonosti vaimeneva taajuuskomponentti rajoittaa siirtokapasiteettia. Voimajärjestelmän stabiiliutta voidaan esittää Wide Area Monitoring -järjestelmien (WAMS) avulla. WAMS perustuu Phasor Measurement -laitteen (PMU) reaaliaikaiseen mittaustekniikkaan. Jännitteen vaihekulman mittaaminen mahdollistaa voimajärjestelmän tilan määrittämisen reaaliajassa. Työssä on esitelty Fingridin käytössä oleva WAMS ja lisäksi esitelty kolmen eri laitetoimittajan WAMS:n rakennetta ja operaattorin käyttöön tarkoitettuja käyttöliittymiä. WAMS:n rakenteet ovat pääpiirteittäin samanlaisia, mutta stabiiliuden visuaalisessa esittämisessä on eroja. PMU -mittaustietoja on mahdollista tuoda käytönvalvontajärjestelmään erillisellä tiedonsiirtoprotokollalla. PMU-mittaustiedon hyödyntäminen käytönvalvontajärjestelmän toimintaaluenäytöllä mahdollistaa verkon tilan esittämisen reaaliajassa. Roottorin kulmastabiilius esitetään Fingridin käytönvalvontajärjestelmässä vaihekulmaerojen avulla ja työssä on esitetty, kuinka vaihekulmaeron arvolla on vaikutus tehonsiirtoon. Vaihekulmaeron arvo kuvaa vian jälkeisen tehoheilahtelun voimakkuutta. PMU-mittaustiedon esittäminen antaa operaattorille selkeämmän kuvan ylläpitää tehonsiirto turvallisella tasolla ja epästabiilin heilahtelun havainnoiminen vähentää suurhäiriön riskiä. Tulevaisuudessa siirtoverkon kehittyessä tarvitaan operaattorin käyttöön myös nopeita stabiilisuutta esittäviä työkaluja.

Monitoring system for small sized photovoltaic power plants

This paper presents a monitoring system devoted to small sized photovoltaic (PV) power plants. The system is characterized by: a high level of integration; a low cost, when compared to the cost of the PV system to be monitored; and an easy installation in the majority of the PV plants with installed power of some kW. The system is able to collect, store, process and display electrical and meteorological parameters that are crucial when monitoring PV facilities. The identification of failures in the PV system and the elaboration of performance analysis of such facilities are other important characteristics of the developed system. The access to the information about the monitored facilities is achieved by using a web application, which was developed with a focus on the mobile devices. In addition, there is the possibility of an integration between the developed monitoring system and the central supervision system of Martifer Solar (a company focused on the development, operation and maintenance of PV systems).

The impact of poor power quality in solar photovoltaic microgeneration: technical problems and losses of revenue

This paper presents a critical and quantitative analysis of the influence of the Power Quality in grid connected solar photovoltaic microgeneration installations. First are introduced the main regulations and legislation related with the solar photovoltaic microgeneration, in Portugal and Europe. Next are presented Power Quality monitoring results obtained from two residential solar photovoltaic installations located in the north of Portugal, and is explained how the Power Quality events affect the operation of these installations. Afterwards, it is described a methodology to estimate the energy production losses and the impact in the revenue caused by the abnormal operation of the electrical installation. This is done by comparing the amount of energy that was injected into the power grid with the theoretical value of energy that could be injected in normal conditions. The performed analysis shows that Power Quality severally affects the solar photovoltaic installations operation. The losses of revenue in the two monitored installations M1 and M2 are estimated in about 27% and 22%, respectively.

In-process grinding monitoring through acoustic emission

This work aims to investigate the efficiency of digital signal processing tools of acoustic emission signals in order to detect thermal damages in grinding processes. To accomplish such a goal, an experimental work was carried out for 15 runs in a surface grinding machine operating with an aluminum oxide grinding wheel and ABNT 1045 Steel as work material. The acoustic emission signals were acquired from a fixed sensor placed on the workpiece holder. A high sampling rate data acquisition system working at 2.5 MHz was used to collect the raw acoustic emission instead of the root mean square value usually employed. Many statistical analyses have shown to be effective to detect burn, such as the root mean square (RMS), correlation of the AE, constant false alarm rate (CFAR), ratio of power (ROP) and mean-value deviance (MVD). However, the CFAR, ROP, Kurtosis and correlation of the AE have been presented more sensitive than the RMS. Copyright © 2006 by ABCM.

Power flow optimization for grid connected inverter using evolutionary algorithm and additional control loop

In this work it is proposed to validate an evolutionary tuning algorithm in plants composed by a grid connected inverter. The optimization aims the tuning of the slopes of P-Ω and Q-V curves so that the system is stable, damped and minimum settling time. Simulation and experimental results are presented to prove the feasibility of the proposed approach. However, experimental results demonstrate a compromising effect of grid frequency oscillations in the active power transferring. In addition, it was proposed an additional loop to compensate this effect ensuring a constant active power flow. © 2011 IEEE.

Development and verification of control and protection strategies in hybrid AC/DC power systems for smart grid applications

Modern power networks incorporate communications and information technology infrastructure into the electrical power system to create a smart grid in terms of control and operation. The smart grid enables real-time communication and control between consumers and utility companies allowing suppliers to optimize energy usage based on price preference and system technical issues. The smart grid design aims to provide overall power system monitoring, create protection and control strategies to maintain system performance, stability and security. This dissertation contributed to the development of a unique and novel smart grid test-bed laboratory with integrated monitoring, protection and control systems. This test-bed was used as a platform to test the smart grid operational ideas developed here. The implementation of this system in the real-time software creates an environment for studying, implementing and verifying novel control and protection schemes developed in this dissertation. Phasor measurement techniques were developed using the available Data Acquisition (DAQ) devices in order to monitor all points in the power system in real time. This provides a practical view of system parameter changes, system abnormal conditions and its stability and security information system. These developments provide valuable measurements for technical power system operators in the energy control centers. Phasor Measurement technology is an excellent solution for improving system planning, operation and energy trading in addition to enabling advanced applications in Wide Area Monitoring, Protection and Control (WAMPAC). Moreover, a virtual protection system was developed and implemented in the smart grid laboratory with integrated functionality for wide area applications. Experiments and procedures were developed in the system in order to detect the system abnormal conditions and apply proper remedies to heal the system. A design for DC microgrid was developed to integrate it to the AC system with appropriate control capability. This system represents realistic hybrid AC/DC microgrids connectivity to the AC side to study the use of such architecture in system operation to help remedy system abnormal conditions. In addition, this dissertation explored the challenges and feasibility of the implementation of real-time system analysis features in order to monitor the system security and stability measures. These indices are measured experimentally during the operation of the developed hybrid AC/DC microgrids. Furthermore, a real-time optimal power flow system was implemented to optimally manage the power sharing between AC generators and DC side resources. A study relating to real-time energy management algorithm in hybrid microgrids was performed to evaluate the effects of using energy storage resources and their use in mitigating heavy load impacts on system stability and operational security.

Survey on demand side sensitivity to power quality in Ireland

Power systems require a reliable supply and good power quality. The impact of power supply interruptions is well acknowledged and well quantified. However, a system may perform reliably without any interruptions but may have poor power quality. Although poor power quality has cost implications for all actors in the electrical power systems, only some users are aware of its impact. Power system operators are much attuned to the impact of low power quality on their equipment and have the appropriate monitoring systems in place. However, over recent years certain industries have come increasingly vulnerable to negative cost implications of poor power quality arising from changes in their load characteristics and load sensitivities, and therefore increasingly implement power quality monitoring and mitigation solutions. This paper reviews several historical studies which investigate the cost implications of poor power quality on industry. These surveys are largely focused on outages, whilst the impact of poor power quality such as harmonics, short interruptions, voltage dips and swells, and transients is less well studied and understood. This paper examines the difficulties in quantifying the costs of poor power quality, and uses the chi-squared method to determine the consequences for industry of power quality phenomenon using a case study of over 40 manufacturing and data centres in Ireland.

Development and Verification of Control and Protection Strategies in Hybrid AC/DC Power Systems for Smart Grid Applications

Modern power networks incorporate communications and information technology infrastructure into the electrical power system to create a smart grid in terms of control and operation. The smart grid enables real-time communication and control between consumers and utility companies allowing suppliers to optimize energy usage based on price preference and system technical issues. The smart grid design aims to provide overall power system monitoring, create protection and control strategies to maintain system performance, stability and security. This dissertation contributed to the development of a unique and novel smart grid test-bed laboratory with integrated monitoring, protection and control systems. This test-bed was used as a platform to test the smart grid operational ideas developed here. The implementation of this system in the real-time software creates an environment for studying, implementing and verifying novel control and protection schemes developed in this dissertation. Phasor measurement techniques were developed using the available Data Acquisition (DAQ) devices in order to monitor all points in the power system in real time. This provides a practical view of system parameter changes, system abnormal conditions and its stability and security information system. These developments provide valuable measurements for technical power system operators in the energy control centers. Phasor Measurement technology is an excellent solution for improving system planning, operation and energy trading in addition to enabling advanced applications in Wide Area Monitoring, Protection and Control (WAMPAC). Moreover, a virtual protection system was developed and implemented in the smart grid laboratory with integrated functionality for wide area applications. Experiments and procedures were developed in the system in order to detect the system abnormal conditions and apply proper remedies to heal the system. A design for DC microgrid was developed to integrate it to the AC system with appropriate control capability. This system represents realistic hybrid AC/DC microgrids connectivity to the AC side to study the use of such architecture in system operation to help remedy system abnormal conditions. In addition, this dissertation explored the challenges and feasibility of the implementation of real-time system analysis features in order to monitor the system security and stability measures. These indices are measured experimentally during the operation of the developed hybrid AC/DC microgrids. Furthermore, a real-time optimal power flow system was implemented to optimally manage the power sharing between AC generators and DC side resources. A study relating to real-time energy management algorithm in hybrid microgrids was performed to evaluate the effects of using energy storage resources and their use in mitigating heavy load impacts on system stability and operational security.

Three-phase harmonic distortion state estimation algorithm based on evolutionary strategies

This paper presents a new methodology to estimate unbalanced harmonic distortions in a power system, based on measurements of a limited number of given sites. The algorithm utilizes evolutionary strategies (ES), a development branch of evolutionary algorithms. The problem solving algorithm herein proposed makes use of data from various power quality meters, which can either be synchronized by high technology GPS devices or by using information from a fundamental frequency load flow, what makes the overall power quality monitoring system much less costly. The ES based harmonic estimation model is applied to a 14 bus network to compare its performance to a conventional Monte Carlo approach. It is also applied to a 50 bus subtransmission network in order to compare the three-phase and single-phase approaches as well as the robustness of the proposed method. (C) 2010 Elsevier B.V. All rights reserved.

Produção Sustentável em BT- Análise de Características de Contadores Inteligentes

A crescente necessidade de reduzir a dependência energética e a emissão de gases de efeito de estufa levou à adoção de uma série de políticas a nível europeu com vista a aumentar a eficiência energética e nível de controlo de equipamentos, reduzir o consumo e aumentar a percentagem de energia produzida a partir de fontes renováveis. Estas medidas levaram ao desenvolvimento de duas situações críticas para o setor elétrico: a substituição das cargas lineares tradicionais, pouco eficientes, por cargas não-lineares mais eficientes e o aparecimento da produção distribuída de energia a partir de fontes renováveis. Embora apresentem vantagens bem documentadas, ambas as situações podem afetar negativamente a qualidade de energia elétrica na rede de distribuição, principalmente na rede de baixa tensão onde é feita a ligação com a maior parte dos clientes e onde se encontram as cargas não-lineares e a ligação às fontes de energia descentralizadas. Isto significa que a monitorização da qualidade de energia tem, atualmente, uma importância acrescida devido aos custos relacionados com perdas inerentes à falta de qualidade de energia elétrica na rede e à necessidade de verificar que determinados parâmetros relacionados com a qualidade de energia elétrica se encontram dentro dos limites previstos nas normas e nos contratos com clientes de forma a evitar disputas ou reclamações. Neste sentido, a rede de distribuição tem vindo a sofrer alterações a nível das subestações e dos postos de transformação que visam aumentar a visibilidade da qualidade de energia na rede em tempo real. No entanto, estas medidas só permitem monitorizar a qualidade de energia até aos postos de transformação de média para baixa tensão, não revelando o estado real da qualidade de energia nos pontos de entrega ao cliente. A monitorização nestes pontos é feita periodicamente e não em tempo real, ficando aquém do necessário para assegurar a deteção correta de problemas de qualidade de energia no lado do consumidor. De facto, a metodologia de monitorização utilizada atualmente envolve o envio de técnicos ao local onde surgiu uma reclamação ou a um ponto de medição previsto para instalar um analisador de energia que permanece na instalação durante um determinado período de tempo. Este tipo de monitorização à posteriori impossibilita desde logo a deteção do problema de qualidade de energia que levou à reclamação, caso não se trate de um problema contínuo. Na melhor situação, o aparelho poderá detetar uma réplica do evento, mas a larga percentagem anomalias ficam fora deste processo por serem extemporâneas. De facto, para detetar o evento que deu origem ao problema é necessário monitorizar permanentemente a qualidade de energia. No entanto este método de monitorização implica a instalação permanente de equipamentos e não é viável do ponto de vista das empresas de distribuição de energia já que os equipamentos têm custos demasiado elevados e implicam a necessidade de espaços maiores nos pontos de entrega para conter os equipamentos e o contador elétrico. Uma alternativa possível que pode tornar viável a monitorização permanente da qualidade de energia consiste na introdução de uma funcionalidade de monitorização nos contadores de energia de determinados pontos da rede de distribuição. Os contadores são obrigatórios em todas as instalações ligadas à rede, para efeitos de faturação. Tradicionalmente estes contadores são eletromecânicos e recentemente começaram a ser substituídos por contadores inteligentes (smart meters), de natureza eletrónica, que para além de fazer a contagem de energia permitem a recolha de informação sobre outros parâmetros e aplicação de uma serie de funcionalidades pelo operador de rede de distribuição devido às suas capacidades de comunicação. A reutilização deste equipamento com finalidade de analisar a qualidade da energia junto dos pontos de entrega surge assim como uma forma privilegiada dado que se trata essencialmente de explorar algumas das suas características adicionais. Este trabalho tem como objetivo analisar a possibilidade descrita de monitorizar a qualidade de energia elétrica de forma permanente no ponto de entrega ao cliente através da utilização do contador elétrico do mesmo e elaborar um conjunto de requisitos para o contador tendo em conta a normalização aplicável, as características dos equipamentos utilizados atualmente pelo operador de rede e as necessidades do sistema elétrico relativamente à monitorização de qualidade de energia.

Automatic meter reading – benefits and applications

In liberalized electricity markets, which have taken place in many countries over the world, the electricity distribution companies operate in the competitive conditions. Therefore, accurate information about the customers’ energy consumption plays an essential role for the budget keeping of the distribution company and for correct planning and operation of the distribution network. This master’s thesis is focused on the description of the possible benefits for the electric utilities and residential customers from the automatic meter reading system usage. Major benefits of the AMR, illustrated in the thesis, are distribution network management, power quality monitoring, load modelling, and detection of the illegal usage of the electricity. By the example of the power system state estimation, it was illustrated that even the partial installation of the AMR in the customer side leads to more accurate data about the voltage and power levels in the whole network. The thesis also contains the description of the present situation of the AMR integration in Russia.

Study of thresholds to burning in surface grinding process

This work aims at finding out the threshold to burning in surface grinding process. Acoustic emission and electric power signals are acquired from an analog-digital converter and processed through algorithms in order to generate a control signal to inform the operator or interrupt the process in the case of burning occurrence. The thresholds that dictate the situation of burn and non-burn were studied as well as a comparison between the two parameters was carried out. In the experimental work one type of steel (ABNT-1045 annealed) and one type of grinding wheel referred to as TARGA model 3TG80.3-NV were employed. Copyright © 2005 by ABCM.

A Influência da Referência de Tensão na Avaliação de Indicadores de Qualidade de Energia

This paper discusses the importance of the voltage referential for power quality monitoring and power systempsilas instrumentation. Considering the operating conditions of simple power circuits, it will be demonstrated that an incorrect choice of the voltages referential may result in erroneous quantification of some power quality indices, especially in three-phase four wire circuits. The use of a virtual reference point and the neutral conductor as reference have been considered and the simulation results confirm the influence of the voltage reference selection in the evaluation of total harmonic distortion, unbalance factors and voltage sags. Finally a way of linking both methods will be discussed by means of Blakesleypsilas theorem. © Copyright 2010 IEEE - All Rights Reserved.

Avaliação experimental de um sistema não linear para extração de energia através de vibrações utilizando material piezelétrico

Pós-graduação em Engenharia Mecânica - FEIS