Compliance verification methodology for renewable generation integration. Application to island power grids

261 p.This thesis proposes a new methodology to validate the integration of renewable generation to install in island power grids. In weak power grids, the penetration of non-synchronous power generation can be challenging. Furthermore, system operators often impose strict technical requirements. In order to streamline grid code compliance verification, this thesis presents a simulation based procedure focused on most critical rules in isolated power grids: Frequency Ride-Through, Low Voltage Ride-Through and voltage and current unbalance. The methodology presented in this thesis proposes a generic and reduced grid model as equivalent system suitable for both simulating the static and dynamic performance of a selected power system for interconnection and design purposes, and for verifying the compliance of aforementioned technical requirements. Depending on the disturbance to be represented and on sensitivity studies of the model parameters, the generic grid model must be then particularised, in order to obtain a particular grid model. Finally, the grid model has to be parameterised based on grid characteristics and grid code limits, resulting into a parameterised grid model. In the present thesis, the methodology is applied to three study cases, where the installation of a renewable power plant is under study: a medium size island grid, Terceira island in the Açores and Fuerteventura-Lanzarote system. The numerical application to these three study cases backs the validity of the methodology proposed in the present thesis

Modelling of Resistive Type Superconducting Fault Current Limiter for HVDC Grids

The protection of high voltage direct current (HVDC) grids is a challenge considering that the protection system must detect, locate, and interrupt large fault currents in a few milliseconds. Resistive type superconducting fault current limiters (R-SFCL) can help solve that difficult task, reducing the extremely demanding ratings of HVDC circuit breakers. This paper presents different approaches to model R-SFCLs in order to analyze their suitability for assessing the performance of HVDC grid protection, including the step model, the exponential model, the RQ model, and the magneto-thermal model. In the first instance, the R-SFCL models are evaluated in a test grid to analyze their parameterisation and select the most adequate model for the study of HVDC grids. The RQ model is finally chosen for its simplicity but closer behavior to the magneto thermal model in terms of fault resistance dependency and resistance evolution curve. Then, the performance of an RQ type R-SFCL model in conjunction with a mechanical circuit breaker is evaluated in a multiterminal HVDC grid with different fault cases. This way, fault currents are greatly decreased as well as circuit breaker requirements. Hence, the R-SFCL under study enables a reliable protection of the HVDC grid

Teknologia elektrikoa

Helburuak: Sektore elektrikoan gaur egun erabiltzen diren teknologiei buruzko oinarrizko ezagutza bat lortzea. Norentzat: Industria Ingeniaritzako 4. mailako Teknologia Elektrikoa I ikasgaiko ikasleentzat.Teknologia Elektrikoa I -1. Energia-sistema elektrikoa -2. Garraio- eta banaketa-sare elektrikoak -3. Lineen parametroak eta ereduak -4. Energia-sare elektrikoetako elementuak -5. Behe-Tentsioko instalazioak -6. Akatsak -7. Babesgailuak -8. Gaintentsioen aurkako babesa -9. Lur-konexioa

Goi-Tentsioko linea eta kableak

Helburuak: Goi-Tentsioko linea eta kableen egoera iraunkorreko kalkulu elektrikoak burutzeko oinarriak azaltzea. Norentzat: Goi-Tentsioko linea eta kableekin kalkulu elektrikoak egin behar dituztenentzat.Goi-Tentsioko aireko lineak -1. Sarrera -2. Parametro elektrikoak -3. Erregimen iraunkorreko funtzionamendua -4. Anpazitatearen kalkulua Goi-Tentsioko lur azpiko lineak -1. Sarrera -2. Parametro elektrikoak -4. Anpazitate

Methodology for Tuning MTDC Supervisory and Frequency-Response Control Systems at Terminal Level under Over-Frequency Events

This paper proposes a methodology for tuning a supervisory and frequency-response outer loop control system of a multi-terminal direct current (MTDC) grid designed to transmit o_shore wind energy to an onshore AC grid, and to provide frequency support during over-frequency events. The control structure is based on a master–slave scheme and ensures the achievement of frequency response, with specific implementation of the UK national grid code limited-frequency sensitive (LFSM) and frequency-sensitive (FSM) modes. The onshore AC grid is modelled with an equivalent frequency-response model to simulate the onshore AC grid dynamics under frequency deviations. The main innovation of this paper is the development of a methodology for tuning simultaneously two hierarchical levels of a MTDC coordinated control structure, i.e., the MTDC supervisor, given by the active power set point for slave terminal, and the slope of frequency-response functions at onshore terminals. Based on these two hierarchical levels, di_erent strategies are evaluated in terms of frequency peak reductions and change of the frequency order type. Moreover, tuning guidance is given when a di_erent MTDC control structure or di_erent synchronous generator characteristics of the onshore AC grid are considered.This research was funded by the Spanish Ministry of Economy, Industry and Competitiveness (project ENE2016-79145-R AEI/FEDER, UE) and the Basque Government (project KK-2017/00083, and research group GISEL, grant number IT1083-16

Field validation of gap-type overhead conductor creep

Gap-type overhead conductor sag-tension calculations based on experimental conductor creep tests are based on stress-strain and metallurgical creep tests. Although for bi-metallic conductors, these tests are carried out for both the core and the full conductor, for gap-type overhead conductors the aluminum metallurgical creep is usually neglected and the full conductor metallurgical creep is not carried out. The purpose of the presented study is the validation of these calculation methods. For this purpose, field measurements have been obtained in a pilot line in operation. The gap-type conductor installation process has been measured and the conductor creep has been monitored during three years of line operation. In order to model relevant events such as the pre-sagging and sagging steps during the installation, and ice and wind events during the operation, a flexible sag-tension calculation method has been used. Besides, the widely used graphical sag-tension method has also been evaluated, obtaining similar results as the flexible method. The tension-decrease is used as the indicator of the creep. The calculated and measured tension-decrease values are close. Therefore, it is concluded that the sag-tension calculations based on experimental conductor creep tests are valid to represent the actual creep of the conductor in operation.This work was supported by the Ministerio de Economía, Industria y Competitividad, Spain, [DPI2013-44502-R and DPI2016-77215-R (AEI/FEDER, UE)]; and by the University of the Basque Country UPV/EHU [EHU16/19]

Design of an Anti-Corona Device for HVAC Substation Connectors

One of the aspects to consider during high-voltage (HV) equipment design is the reduction in the probability of corona effect onset. Indeed, the corona effect is related to high electric field values beyond the equipment’s insulation levels and insulation strength, among other factors. This issue can be addressed during the design step, either by modifying the geometry of the electrical device or by including additional elements in the equipment structure to smooth out the voltage gradient along critical regions, such as anti-corona devices. The study of anti-corona devices for HV insulators is well documented, in contrast to substation connectors. Therefore, the present study proposed the design of a novel anti-corona device for HV substation connectors, including a method for the selection of its dimensions. This study shows that the relationship between the dimensional design variables and the critical electrical field on the connector is described by linear and rational functions. Thus, the design process times are cut down due to a reduction in the number of simulations required to run the assessment of the anti-corona device arrangement impact.The authors wish to thank the support from the Basque Government (GISEL research group IT1191-19 and ELEKTRIKER research group IT164-22), as well as from the University of the Basque Country UPV/EHU (GISEL research group GIU18/181 and ELEKTRIKER research group GIU20/034)

Energia Elektrikoaren Sorkuntza

Helburuak: Sektore elektrikoan gaur egun energia elektrikoa sortzeko erabiltzen diren teknologiei buruzko oinarrizko ezagutza bat lortzea. Norentzat: Energia elektrikoaren sorkuntza ikasgai bezala duten ikasleentzatEdukia: 1. Eskariari erantzuna ematea 2. Sistemaren kudeaketa ekonomikoa. Merkatu elektrikoa 3. Sorkuntza konbentzionala 4. Energia berriztagarriak eta baterako sorkuntza 5. Sorkuntzaren sare-konexioa 6. Sorgailu trifasikoak 7. Sorgailu elektrikoen egonkortasuna 8. Zentralen kontrola 9. Zentralen babesaLiburu honek UPV/EHUko Euskararen Arloko Errektoreordetzaren dirulaguntza jaso d

Compliance verification methodology for renewable generation integration. Application to island power grids

261 p.This thesis proposes a new methodology to validate the integration of renewable generation to install in island power grids. In weak power grids, the penetration of non-synchronous power generation can be challenging. Furthermore, system operators often impose strict technical requirements. In order to streamline grid code compliance verification, this thesis presents a simulation based procedure focused on most critical rules in isolated power grids: Frequency Ride-Through, Low Voltage Ride-Through and voltage and current unbalance. The methodology presented in this thesis proposes a generic and reduced grid model as equivalent system suitable for both simulating the static and dynamic performance of a selected power system for interconnection and design purposes, and for verifying the compliance of aforementioned technical requirements. Depending on the disturbance to be represented and on sensitivity studies of the model parameters, the generic grid model must be then particularised, in order to obtain a particular grid model. Finally, the grid model has to be parameterised based on grid characteristics and grid code limits, resulting into a parameterised grid model. In the present thesis, the methodology is applied to three study cases, where the installation of a renewable power plant is under study: a medium size island grid, Terceira island in the Açores and Fuerteventura-Lanzarote system. The numerical application to these three study cases backs the validity of the methodology proposed in the present thesis

Teknologia elektrikoa

Helburuak: Sektore elektrikoan gaur egun erabiltzen diren teknologiei buruzko oinarrizko ezagutza bat lortzea. Norentzat: Industria Ingeniaritzako 4. mailako Teknologia Elektrikoa I ikasgaiko ikasleentzat.Teknologia Elektrikoa I -1. Energia-sistema elektrikoa -2. Garraio- eta banaketa-sare elektrikoak -3. Lineen parametroak eta ereduak -4. Energia-sare elektrikoetako elementuak -5. Behe-Tentsioko instalazioak -6. Akatsak -7. Babesgailuak -8. Gaintentsioen aurkako babesa -9. Lur-konexioa