Ahmed Altaher | Institut polytechnique de Grenoble - Grenoble INP (original) (raw)

Papers by Ahmed Altaher

Research paper thumbnail of On benchmarking of networked cyber-physical systems

Benchmarking and testing are important steps toward ensuring reliable service of cyber-physical s... more Benchmarking and testing are important steps toward ensuring reliable service of cyber-physical systems. Site acceptance testing of communication networks in smart grids is difficult in terms of safety due to the electrical power nature and real-time constraints. Ethernet has become de facto for smart automation systems in electric grid applications. Engineers, therefore, should consider benchmark testing regarding quality of service networking parameters to avoid degradation of the system reliability. Hence, testing methodology should consider both the dynamics of the Ethernet network and the automation system, i.e. testers should take into account the behavior of automation when communication faults take place. This paper describes how an integrated benchmarking methodology provides empirical evaluation of Ethernet services in industrial automation networks. The results prove the technical feasibility of this method and motivates using commercial-off-the-shelf components (COTS).

Research paper thumbnail of Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture

Present-day developments, in electrical power transmission and distribution, require consideratio... more Present-day developments, in electrical power transmission and distribution, require considerations of the status quo. In other meaning, international regulations enforce increasing of reliability and reducing of environment impact, correspondingly they motivate developing of dependable systems. Power grids especially intelligent (smart grids) ones become industrial solutions that follow standardized development. The International standardization, in the field of power transmission and distribution, improve technology influences. The rise of dedicated standards for SAS (Substation Automation Systems) communications, such as the leading International Electro-technical Commission standard IEC 61850, enforces modern technological trends in this field. Within this standard, a constraint of low ETE (End-to-End) latency should be respected, and time-critical status transmission must be achieved. This experimental study emphasis on IEC 61850 SAS communication standard, e.g. IEC 61850 GOOSE...

Research paper thumbnail of Performance Evaluation of IEC 61850 safety-related communication architecture

Recent improvements, in electrical power transmission and distribution, require considerations of... more Recent improvements, in electrical power transmission and distribution, require considerations of existing regulations that enforce increasing of reliability and reducing of environment impact. Smart grids become industrial solutions that follow standardized development. It is used to satisfy both the electrical energy supply from producers to consumers and the need for consumers' data transmission to electrical utility and providers. This technology is affected by international standardization in the field of power transmission and distribution. Modern electrical substations, i.e. electrical transmission and distribution stations, are part of smart grids. These substations follow new technological trends [1]. The IEC 61850 standard consists of 10 parts to enforce interoperability between different manufactured devices, e.g. intelligent electronic device (IED), in the substation communication systems [2]. The standard uses high speed time-critical communication to exchange event...

Research paper thumbnail of Whole GICS network data with background traffic

Research paper thumbnail of Mise en œuvre d’un cadre de sûreté de fonctionnement pour les systèmes d'automatisation de sous-stations intelligentes : application à la distribution de l’énergie électrique

Depuis son invention, l'electricite joue un role essentiel dans notre vie quotidienne. L'... more Depuis son invention, l'electricite joue un role essentiel dans notre vie quotidienne. L'apparition des premieres installations de production d'electricite a la fin du XIXeme siecle a ouvert la voie au systeme electrique et a ses sous-systemes. Les consommateurs d'energie electrique exigent un service fiable en termes de stabilite et de securite du reseau electrique. Depuis la liberalisation des marches, les producteurs d'energie electrique, les fournisseurs de services publics et d'equipements, en tant qu'acteurs principaux, suivent une tendance emergente pour satisfaire les demandes des consommateurs. Cette tendance implique l'amelioration des technologies, l'innovation et le respect des normes et des reglementations gouvernementales. Tous ces efforts ont ete qualifies de concept de reseaux intelligents (Smart Grid en anglais) qui evolue pour repondre aux demandes futures.Les sous-stations numeriques modernes et futures faconnent des nœuds essen...

Research paper thumbnail of Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture

Present-day developments, in electrical power transmission and distribution, require consideratio... more Present-day developments, in electrical power transmission and distribution, require considerations of the status quo. In other meaning, international regulations enforce increasing of reliability and reducing of environment impact, correspondingly they motivate developing of dependable systems. Power grids especially intelligent (smart grids) ones become industrial solutions that follow standardized development. The International standardization, in the field of power transmission and distribution, improve technology influences. The rise of dedicated standards for SAS (Substation Automation Systems) communications, such as the leading International Electro-technical Commission standard IEC 61850, enforces modern technological trends in this field. Within this standard, a constraint of low ETE (End-to-End) latency should be respected, and time-critical status transmission must be achieved. This experimental study emphasis on IEC 61850 SAS communication standard, e.g. IEC 61850 GOOSE...

Research paper thumbnail of Implementation of a dependability framework for smart substation automation systems : application to electric energy distribution

Since its invention, Electricity has played a vital role in our everyday life. The appearance of ... more Since its invention, Electricity has played a vital role in our everyday life. The appearance of the first power production facilities in the late nineteenth century paved the way for the electrical power system and its subsystems. Consumers of electric power demand dependable service in terms of power grid stability and safety. Since the liberalization of the markets, producers of electric power, utilities and equipment suppliers, as principal players, are following an emerging trend to satisfy consumers’ demands. This trend involves improving technologies, innovating and respecting standards requirements and governments’ regulations. All these efforts termed as the concept of the Smart Grid that is evolving to meet future demands.Modern and future digital substations shape essential nodes in the grid, where stability of electric power flow, converting of voltage levels and protecting switchyard equipment are among the primary roles of these nodes. The promising standard IEC 61850 ...

Research paper thumbnail of Real-Time safety: Analyzing coordination time for networked automation systems

2021 IEEE 1st International Maghreb Meeting of the Conference on Sciences and Techniques of Automatic Control and Computer Engineering MI-STA

safety is the main concern during electric power fault clearance. The main objective of automatio... more safety is the main concern during electric power fault clearance. The main objective of automation systems, in this circumstance, is to coordinate protection functions to avoid potential risks. These risks may cause both economic and societal losses. The failure of protection coordination could lead to non-clearance of power faults. Besides, the long duration of these faults may lead to melted materials and blasts. Hence, faults continuity causes severe consequences. The role of communication network should be therefore evaluated. This paper analyzes contributions of automation system networks, such as their latency, during faults clearance. To validate network design in safety applications, protection, automation and coordination must respect time-critical constraints. Results prove that faults of communication network and inappropriate configuration can cause delayed arc-flash clearance. Additionally, the paper proposes mitigating techniques such as priority policies and use of virtual local networks to reduce End-To-End delays.

Research paper thumbnail of Dependability optimization of process-level protection in an IEC-61850-based substation

Risk, Reliability and Safety: Innovating Theory and Practice, Sep 14, 2016

Research paper thumbnail of Experimental Evaluation of an IEC 61850-Station Bus Communication Reliability

Recent improvements, in electrical power transmission and distribution, require considerations of... more Recent improvements, in electrical power transmission and distribution, require considerations of existing regulations that enforce increasing of reliability and reducing of environment impact. Smart grids become industrial solutions that follow standardized development. These technologies are affected by international standardization in the field of power transmission and distribution. This study emphasis on modern SAS (Substation Automation System) communication standards, e.g. IEC 61850 GOOSE (Generic Object Oriented Substation Events), to present an experimental method to calculate End-To-End delay by utilizing monitoring capabilities and using network equipment such as SPAN and TAP devices.

Research paper thumbnail of On benchmarking of networked cyber-physical systems

Benchmarking and testing are important steps toward ensuring reliable service of cyber-physical s... more Benchmarking and testing are important steps toward ensuring reliable service of cyber-physical systems. Site acceptance testing of communication networks in smart grids is difficult in terms of safety due to the electrical power nature and real-time constraints. Ethernet has become de facto for smart automation systems in electric grid applications. Engineers, therefore, should consider benchmark testing regarding quality of service networking parameters to avoid degradation of the system reliability. Hence, testing methodology should consider both the dynamics of the Ethernet network and the automation system, i.e. testers should take into account the behavior of automation when communication faults take place. This paper describes how an integrated benchmarking methodology provides empirical evaluation of Ethernet services in industrial automation networks. The results prove the technical feasibility of this method and motivates using commercial-off-the-shelf components (COTS).

Research paper thumbnail of Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture

Present-day developments, in electrical power transmission and distribution, require consideratio... more Present-day developments, in electrical power transmission and distribution, require considerations of the status quo. In other meaning, international regulations enforce increasing of reliability and reducing of environment impact, correspondingly they motivate developing of dependable systems. Power grids especially intelligent (smart grids) ones become industrial solutions that follow standardized development. The International standardization, in the field of power transmission and distribution, improve technology influences. The rise of dedicated standards for SAS (Substation Automation Systems) communications, such as the leading International Electro-technical Commission standard IEC 61850, enforces modern technological trends in this field. Within this standard, a constraint of low ETE (End-to-End) latency should be respected, and time-critical status transmission must be achieved. This experimental study emphasis on IEC 61850 SAS communication standard, e.g. IEC 61850 GOOSE...

Research paper thumbnail of Performance Evaluation of IEC 61850 safety-related communication architecture

Recent improvements, in electrical power transmission and distribution, require considerations of... more Recent improvements, in electrical power transmission and distribution, require considerations of existing regulations that enforce increasing of reliability and reducing of environment impact. Smart grids become industrial solutions that follow standardized development. It is used to satisfy both the electrical energy supply from producers to consumers and the need for consumers' data transmission to electrical utility and providers. This technology is affected by international standardization in the field of power transmission and distribution. Modern electrical substations, i.e. electrical transmission and distribution stations, are part of smart grids. These substations follow new technological trends [1]. The IEC 61850 standard consists of 10 parts to enforce interoperability between different manufactured devices, e.g. intelligent electronic device (IED), in the substation communication systems [2]. The standard uses high speed time-critical communication to exchange event...

Research paper thumbnail of Whole GICS network data with background traffic

Research paper thumbnail of Mise en œuvre d’un cadre de sûreté de fonctionnement pour les systèmes d'automatisation de sous-stations intelligentes : application à la distribution de l’énergie électrique

Depuis son invention, l'electricite joue un role essentiel dans notre vie quotidienne. L'... more Depuis son invention, l'electricite joue un role essentiel dans notre vie quotidienne. L'apparition des premieres installations de production d'electricite a la fin du XIXeme siecle a ouvert la voie au systeme electrique et a ses sous-systemes. Les consommateurs d'energie electrique exigent un service fiable en termes de stabilite et de securite du reseau electrique. Depuis la liberalisation des marches, les producteurs d'energie electrique, les fournisseurs de services publics et d'equipements, en tant qu'acteurs principaux, suivent une tendance emergente pour satisfaire les demandes des consommateurs. Cette tendance implique l'amelioration des technologies, l'innovation et le respect des normes et des reglementations gouvernementales. Tous ces efforts ont ete qualifies de concept de reseaux intelligents (Smart Grid en anglais) qui evolue pour repondre aux demandes futures.Les sous-stations numeriques modernes et futures faconnent des nœuds essen...

Research paper thumbnail of Evaluation of Time-Critical Communications for IEC 61850-Substation Network Architecture

Present-day developments, in electrical power transmission and distribution, require consideratio... more Present-day developments, in electrical power transmission and distribution, require considerations of the status quo. In other meaning, international regulations enforce increasing of reliability and reducing of environment impact, correspondingly they motivate developing of dependable systems. Power grids especially intelligent (smart grids) ones become industrial solutions that follow standardized development. The International standardization, in the field of power transmission and distribution, improve technology influences. The rise of dedicated standards for SAS (Substation Automation Systems) communications, such as the leading International Electro-technical Commission standard IEC 61850, enforces modern technological trends in this field. Within this standard, a constraint of low ETE (End-to-End) latency should be respected, and time-critical status transmission must be achieved. This experimental study emphasis on IEC 61850 SAS communication standard, e.g. IEC 61850 GOOSE...

Research paper thumbnail of Implementation of a dependability framework for smart substation automation systems : application to electric energy distribution

Since its invention, Electricity has played a vital role in our everyday life. The appearance of ... more Since its invention, Electricity has played a vital role in our everyday life. The appearance of the first power production facilities in the late nineteenth century paved the way for the electrical power system and its subsystems. Consumers of electric power demand dependable service in terms of power grid stability and safety. Since the liberalization of the markets, producers of electric power, utilities and equipment suppliers, as principal players, are following an emerging trend to satisfy consumers’ demands. This trend involves improving technologies, innovating and respecting standards requirements and governments’ regulations. All these efforts termed as the concept of the Smart Grid that is evolving to meet future demands.Modern and future digital substations shape essential nodes in the grid, where stability of electric power flow, converting of voltage levels and protecting switchyard equipment are among the primary roles of these nodes. The promising standard IEC 61850 ...

Research paper thumbnail of Real-Time safety: Analyzing coordination time for networked automation systems

2021 IEEE 1st International Maghreb Meeting of the Conference on Sciences and Techniques of Automatic Control and Computer Engineering MI-STA

safety is the main concern during electric power fault clearance. The main objective of automatio... more safety is the main concern during electric power fault clearance. The main objective of automation systems, in this circumstance, is to coordinate protection functions to avoid potential risks. These risks may cause both economic and societal losses. The failure of protection coordination could lead to non-clearance of power faults. Besides, the long duration of these faults may lead to melted materials and blasts. Hence, faults continuity causes severe consequences. The role of communication network should be therefore evaluated. This paper analyzes contributions of automation system networks, such as their latency, during faults clearance. To validate network design in safety applications, protection, automation and coordination must respect time-critical constraints. Results prove that faults of communication network and inappropriate configuration can cause delayed arc-flash clearance. Additionally, the paper proposes mitigating techniques such as priority policies and use of virtual local networks to reduce End-To-End delays.

Research paper thumbnail of Dependability optimization of process-level protection in an IEC-61850-based substation

Risk, Reliability and Safety: Innovating Theory and Practice, Sep 14, 2016

Research paper thumbnail of Experimental Evaluation of an IEC 61850-Station Bus Communication Reliability

Recent improvements, in electrical power transmission and distribution, require considerations of... more Recent improvements, in electrical power transmission and distribution, require considerations of existing regulations that enforce increasing of reliability and reducing of environment impact. Smart grids become industrial solutions that follow standardized development. These technologies are affected by international standardization in the field of power transmission and distribution. This study emphasis on modern SAS (Substation Automation System) communication standards, e.g. IEC 61850 GOOSE (Generic Object Oriented Substation Events), to present an experimental method to calculate End-To-End delay by utilizing monitoring capabilities and using network equipment such as SPAN and TAP devices.