S. Sangiovanni - Academia.edu (original) (raw)
Papers by S. Sangiovanni
2020 AEIT International Annual Conference (AEIT), 2020
In the last years, the frequency and the intensity of adverse meteorological conditions are on th... more In the last years, the frequency and the intensity of adverse meteorological conditions are on the rise and climate changes have the potential to affect negatively the electrical systems in many different ways. Local or extended electrical outages have been and are caused by extremely severe negative meteorological events of different nature, like strong wind, wet snow, heavy rain and heat waves. Of course, such interruptions of electrical system affect also critical infrastructures with a negative impact on all the human and industrial activities. To face this reality, the Italian Regulatory Authority for Energy, Networks and the Environment (ARERA), established new more stringent rules to maintain high standards of power quality services also through more resilient electrical system. For this reason, there have been established very ambitious benchmark values for the key performance indicators, normally used to evaluate the quality of electric service. With the aim to increase the resilience of the distribution electrical networks, the DSOs are studying and developing new grid operations with improved assets adopting also advanced electrical technologies. For this reason, in the last decades were developed medium voltage cable joints much easier and faster to install. These joints can make the system more vulnerable for possible imperfections introduced during the construction phase for unperfect manpower and for the complexity of the operations.
Sensors, Nov 27, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
2019 IEEE 20th International Conference on Dielectric Liquids (ICDL), 2019
The latest version of the standard IEC 60156 “Insulating liquids - Determination of the breakdown... more The latest version of the standard IEC 60156 “Insulating liquids - Determination of the breakdown voltage at power frequency - Test method” was published in August 2018 as Edition 3.0. This standard follows the two previously published versions in 1963 and 1995. The test method described in practically all IEC 60156 versions defines a procedure in which the insulating liquid is subjected to an increasing AC electrical field until breakdown occurs and it is used for both acceptance testing on unused liquids at the time of their delivery and for establishing the condition of samples taken in monitoring and maintenance of equipment. In this paper the experimental results of 50 Hz breakdown voltages of both mineral and natural ester liquids performed following the tests methods described in the new edition of IEC 60156 are shown. The tests were performed also with the use of different stirring systems.
2020 IEEE 3rd International Conference on Dielectrics (ICD), 2020
The Partial Discharges Inception Voltage (PDIV) determination is believed to be an important test... more The Partial Discharges Inception Voltage (PDIV) determination is believed to be an important test able to describe the behavior of insulating liquids when subjected to high electrical stress. In IEC standardization body, this test procedure is described by the IEC TR 61294 (Determination of the Partial Discharge Inception Voltage). In particular, according to this standard, the inception voltage is defined as the voltage at which at least one single partial discharge (PD) occurs of apparent charge equal to or greater than 100 pC. On the other hands, partial discharges in insulating liquids are random events which occurs within vapor phase regions located somewhere in the proximity of the cathode. These vapor phase regions may be different in number and in dimension in function of the local field so that partial discharge phenomena appear in terms of PD amplitude distribution in which a single pulse greater than 100 pC cannot be relevant to the overall phenomena. With the aim to establish when a significative PD activity is present in insulating liquids, in this paper different criteria for PDIV determination have been adopted and compared. The results of these tests may be of interest when revising the IEC TR 61294 or considering the actual preparation of an ASTM Standard (Project WK65707 - New Test Method for Partial Discharge Inception Voltage Measurement of Insulating Liquids Using Plane and Needle Electrodes).
2020 19th International Conference on Harmonics and Quality of Power (ICHQP), 2020
The paper proposes a generic Matlab-Simulink model to represent quasi-static time-varying non-lin... more The paper proposes a generic Matlab-Simulink model to represent quasi-static time-varying non-linear loads in power systems. The methodology presented allows to combine both deterministic and a probabilistic approaches. The procedure is able to evaluate voltage and current harmonic spectra under uncertainty scenarios in a power system allowing a preevaluation of harmonic disturbances. The methodology allows to simulate load variability taking into account power consumption and harmonic profile changes in time and to evaluate the introduction of new non-linear loads and renewable sources in a generic electrical power system.
2021 AEIT International Annual Conference (AEIT), 2021
In the last years, the summer meteorological conditions became much hotter and more arid as one o... more In the last years, the summer meteorological conditions became much hotter and more arid as one of the consequences of the climate changes. These conditions have caused and are causing an increasing number of unexpected failures in underground medium voltage cables, mainly in correspondence of cable joints which are weak points of the system. The anomalous hot weather conditions during the summer period may last for several days (heatwaves), worsening appreciably the consequence of this phenomenon; the stress obviously increases as the number of the warmer days and lack of rain prolongs, heating cable and joint insulating materials with their internal defects and voids, wherein partial discharge phenomena may be easily triggered at this higher temperature under the action of the electrical field greatly increased in correspondence of such defects and voids. The present paper reports a study on the hotter day sequences in some Italian main cities with the aim to establish a correct definition for the term "heatwave", to be used when dealing with underground cables failure topic.
2020 IEEE International Workshop on Metrology for Industry 4.0 & IoT, 2020
Traditional wireless communication methods tend to saturate in terms of data rate, frequency spec... more Traditional wireless communication methods tend to saturate in terms of data rate, frequency spectrum and reliability. Visible Light Communication (VLC) integrated with the emerging technology of Internet-of-Things (IoT) opens up to a wide range of indoor applications. In this work we will describe the potential of an optical wireless communication infrastructure and we will make a comparison with the emerging 5G and 6G Wi-Fi (RF) technologies.
2019 IEEE 20th International Conference on Dielectric Liquids (ICDL), 2019
The recent evolution in electricity distribution systems has led to the development of new intell... more The recent evolution in electricity distribution systems has led to the development of new intelligent structures, better known as Smart Grids, Microgrids and Prosumers. The consequent advantages regard mainly both economy aspects and environmental safeguard. In a microgrid, producers and consumers can exchange energy in peer-to-peer way. Normally, the microgrid is connected to a Smart Grid in a single common point. In this case, the microgrid can be easily disconnected from the external grid and continue to work in “island” mode. In this condition, local production must be equal to the energy consumed, unless local storage systems are installed on site. In case of a bidirectional management, the source may change in load and vice versa. In this situation, a traditional transformer may work in an overload condition and the protection system may trip, provoking, in the worst conditions, a blackout. In order to avoid this condition, some solutions are here proposed and commented.
INTELEC 07 - 29th International Telecommunications Energy Conference, 2007
An instrument based on FPGA technology able to determine in an only period and with a little numb... more An instrument based on FPGA technology able to determine in an only period and with a little number of samples the fundamental frequency of electrical net signal is been realized. The algorithm implemented on the instrument is a modified version of the well known Curve Fitting Algorithm (CFA) particularly suitable to determine Power Quality Parameters. A study of the uncertainty to evaluate the performances of the instruments is presented too.
Energies, 2021
The reliability of systems and components is a fundamental need for the efficient development of ... more The reliability of systems and components is a fundamental need for the efficient development of a smart distribution grid. In fact, the presence of a fault in one component of the grid could potentially lead to a service interruption and loss of profit. Since faults cannot be avoided, the introduction of a diagnostic scheme could predict the fault of a component in order to carry out predictive maintenance. In this framework, this paper proposes a novel Fault Detection and Isolation (FDI) scheme for AC/DC converters in MV/LV substations. In order to improve the reliability of the FDI procedure, the system architecture includes also an Instrument Fault Detection and Isolation section for identifying faults that could occur on the instruments and sensors involved in the monitoring process of the AC/DC converter. The proposed architecture is scalable, easily upgradable, and uses cost-effective sensors. Tests, carried out on a real test site, have demonstrated the efficacy of the propo...
2020 AEIT International Annual Conference (AEIT), 2020
In the last years, the frequency and the intensity of adverse meteorological conditions are on th... more In the last years, the frequency and the intensity of adverse meteorological conditions are on the rise and climate changes have the potential to affect negatively the electrical systems in many different ways. Local or extended electrical outages have been and are caused by extremely severe negative meteorological events of different nature, like strong wind, wet snow, heavy rain and heat waves. Of course, such interruptions of electrical system affect also critical infrastructures with a negative impact on all the human and industrial activities. To face this reality, the Italian Regulatory Authority for Energy, Networks and the Environment (ARERA), established new more stringent rules to maintain high standards of power quality services also through more resilient electrical system. For this reason, there have been established very ambitious benchmark values for the key performance indicators, normally used to evaluate the quality of electric service. With the aim to increase the resilience of the distribution electrical networks, the DSOs are studying and developing new grid operations with improved assets adopting also advanced electrical technologies. For this reason, in the last decades were developed medium voltage cable joints much easier and faster to install. These joints can make the system more vulnerable for possible imperfections introduced during the construction phase for unperfect manpower and for the complexity of the operations.
Sensors, Nov 27, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
2019 IEEE 20th International Conference on Dielectric Liquids (ICDL), 2019
The latest version of the standard IEC 60156 “Insulating liquids - Determination of the breakdown... more The latest version of the standard IEC 60156 “Insulating liquids - Determination of the breakdown voltage at power frequency - Test method” was published in August 2018 as Edition 3.0. This standard follows the two previously published versions in 1963 and 1995. The test method described in practically all IEC 60156 versions defines a procedure in which the insulating liquid is subjected to an increasing AC electrical field until breakdown occurs and it is used for both acceptance testing on unused liquids at the time of their delivery and for establishing the condition of samples taken in monitoring and maintenance of equipment. In this paper the experimental results of 50 Hz breakdown voltages of both mineral and natural ester liquids performed following the tests methods described in the new edition of IEC 60156 are shown. The tests were performed also with the use of different stirring systems.
2020 IEEE 3rd International Conference on Dielectrics (ICD), 2020
The Partial Discharges Inception Voltage (PDIV) determination is believed to be an important test... more The Partial Discharges Inception Voltage (PDIV) determination is believed to be an important test able to describe the behavior of insulating liquids when subjected to high electrical stress. In IEC standardization body, this test procedure is described by the IEC TR 61294 (Determination of the Partial Discharge Inception Voltage). In particular, according to this standard, the inception voltage is defined as the voltage at which at least one single partial discharge (PD) occurs of apparent charge equal to or greater than 100 pC. On the other hands, partial discharges in insulating liquids are random events which occurs within vapor phase regions located somewhere in the proximity of the cathode. These vapor phase regions may be different in number and in dimension in function of the local field so that partial discharge phenomena appear in terms of PD amplitude distribution in which a single pulse greater than 100 pC cannot be relevant to the overall phenomena. With the aim to establish when a significative PD activity is present in insulating liquids, in this paper different criteria for PDIV determination have been adopted and compared. The results of these tests may be of interest when revising the IEC TR 61294 or considering the actual preparation of an ASTM Standard (Project WK65707 - New Test Method for Partial Discharge Inception Voltage Measurement of Insulating Liquids Using Plane and Needle Electrodes).
2020 19th International Conference on Harmonics and Quality of Power (ICHQP), 2020
The paper proposes a generic Matlab-Simulink model to represent quasi-static time-varying non-lin... more The paper proposes a generic Matlab-Simulink model to represent quasi-static time-varying non-linear loads in power systems. The methodology presented allows to combine both deterministic and a probabilistic approaches. The procedure is able to evaluate voltage and current harmonic spectra under uncertainty scenarios in a power system allowing a preevaluation of harmonic disturbances. The methodology allows to simulate load variability taking into account power consumption and harmonic profile changes in time and to evaluate the introduction of new non-linear loads and renewable sources in a generic electrical power system.
2021 AEIT International Annual Conference (AEIT), 2021
In the last years, the summer meteorological conditions became much hotter and more arid as one o... more In the last years, the summer meteorological conditions became much hotter and more arid as one of the consequences of the climate changes. These conditions have caused and are causing an increasing number of unexpected failures in underground medium voltage cables, mainly in correspondence of cable joints which are weak points of the system. The anomalous hot weather conditions during the summer period may last for several days (heatwaves), worsening appreciably the consequence of this phenomenon; the stress obviously increases as the number of the warmer days and lack of rain prolongs, heating cable and joint insulating materials with their internal defects and voids, wherein partial discharge phenomena may be easily triggered at this higher temperature under the action of the electrical field greatly increased in correspondence of such defects and voids. The present paper reports a study on the hotter day sequences in some Italian main cities with the aim to establish a correct definition for the term "heatwave", to be used when dealing with underground cables failure topic.
2020 IEEE International Workshop on Metrology for Industry 4.0 & IoT, 2020
Traditional wireless communication methods tend to saturate in terms of data rate, frequency spec... more Traditional wireless communication methods tend to saturate in terms of data rate, frequency spectrum and reliability. Visible Light Communication (VLC) integrated with the emerging technology of Internet-of-Things (IoT) opens up to a wide range of indoor applications. In this work we will describe the potential of an optical wireless communication infrastructure and we will make a comparison with the emerging 5G and 6G Wi-Fi (RF) technologies.
2019 IEEE 20th International Conference on Dielectric Liquids (ICDL), 2019
The recent evolution in electricity distribution systems has led to the development of new intell... more The recent evolution in electricity distribution systems has led to the development of new intelligent structures, better known as Smart Grids, Microgrids and Prosumers. The consequent advantages regard mainly both economy aspects and environmental safeguard. In a microgrid, producers and consumers can exchange energy in peer-to-peer way. Normally, the microgrid is connected to a Smart Grid in a single common point. In this case, the microgrid can be easily disconnected from the external grid and continue to work in “island” mode. In this condition, local production must be equal to the energy consumed, unless local storage systems are installed on site. In case of a bidirectional management, the source may change in load and vice versa. In this situation, a traditional transformer may work in an overload condition and the protection system may trip, provoking, in the worst conditions, a blackout. In order to avoid this condition, some solutions are here proposed and commented.
INTELEC 07 - 29th International Telecommunications Energy Conference, 2007
An instrument based on FPGA technology able to determine in an only period and with a little numb... more An instrument based on FPGA technology able to determine in an only period and with a little number of samples the fundamental frequency of electrical net signal is been realized. The algorithm implemented on the instrument is a modified version of the well known Curve Fitting Algorithm (CFA) particularly suitable to determine Power Quality Parameters. A study of the uncertainty to evaluate the performances of the instruments is presented too.
Energies, 2021
The reliability of systems and components is a fundamental need for the efficient development of ... more The reliability of systems and components is a fundamental need for the efficient development of a smart distribution grid. In fact, the presence of a fault in one component of the grid could potentially lead to a service interruption and loss of profit. Since faults cannot be avoided, the introduction of a diagnostic scheme could predict the fault of a component in order to carry out predictive maintenance. In this framework, this paper proposes a novel Fault Detection and Isolation (FDI) scheme for AC/DC converters in MV/LV substations. In order to improve the reliability of the FDI procedure, the system architecture includes also an Instrument Fault Detection and Isolation section for identifying faults that could occur on the instruments and sensors involved in the monitoring process of the AC/DC converter. The proposed architecture is scalable, easily upgradable, and uses cost-effective sensors. Tests, carried out on a real test site, have demonstrated the efficacy of the propo...