CS2AC-UPC - Supervision, Safety and Automatic Control
http://hdl.handle.net/2117/191802
2024-03-28T23:09:06Z
2024-03-28T23:09:06Z
Distributed cooperative control for stepper motors synchronization
Yague, Sauro J.
Reyes Carmenaty, Guillermo
Rolán Blanco, Alejandro
Garcia Cerrada, Aurelio
http://hdl.handle.net/2117/190881
2020-10-09T10:38:13Z
2020-06-16T12:29:58Z
Distributed cooperative control for stepper motors synchronization
Yague, Sauro J.; Reyes Carmenaty, Guillermo; Rolán Blanco, Alejandro; Garcia Cerrada, Aurelio
This paper describes the design and simulation of a distributed cooperative control algorithm based on multi-agents to synchronize a group of stepper motors. Modeling of the two-phase hybrid stepper motor in closed loop is derived in d-q rotary reference frame, based on field-oriented control techniques to provide torque control. The simulation obtained by MATLAB-Simulink shows that the distributed cooperative control effectiveness depends on the network topology defined by the graph.
2020-06-16T12:29:58Z
Yague, Sauro J.
Reyes Carmenaty, Guillermo
Rolán Blanco, Alejandro
Garcia Cerrada, Aurelio
This paper describes the design and simulation of a distributed cooperative control algorithm based on multi-agents to synchronize a group of stepper motors. Modeling of the two-phase hybrid stepper motor in closed loop is derived in d-q rotary reference frame, based on field-oriented control techniques to provide torque control. The simulation obtained by MATLAB-Simulink shows that the distributed cooperative control effectiveness depends on the network topology defined by the graph.
Integration of cold ironing and renewable sources in the Barcelona smart port
Rolán Blanco, Alejandro
Manteca, Paola
Oktar, Rahime
Siano, Pierluigi
http://hdl.handle.net/2117/190877
2021-11-30T01:32:24Z
2020-06-16T12:22:22Z
Integration of cold ironing and renewable sources in the Barcelona smart port
Rolán Blanco, Alejandro; Manteca, Paola; Oktar, Rahime; Siano, Pierluigi
Cold ironing, which is the procedure of supplying shoreside electrical power to a ship at berth when its engines are turned off, arises as the eco-friendly way to deliver power to ships while they are berthed in ports, thus avoiding the use of diesel engines onboard, which provokes the emission of large amounts of greenhouse gases into the atmosphere. The aim of this study is twofold. Firstly, a survey of research developments on cold ironing is carried out in order to show the state of the art on the problem of greenhouse gases emitted by ships while docked and how to tackle it. Current regulations and examples of current ports that make use of technologies for cold ironing purposes are also shown. Secondly, the study proposes the use of a cold ironing system in the port of Barcelona, where the power generation is entirely given by renewable energy systems (wind turbines and photovoltaic panels). The idea is to contribute to the wide spread of cold ironing within smart port microgrids to achieve the goal of zero emissions from berthed ships.
2020-06-16T12:22:22Z
Rolán Blanco, Alejandro
Manteca, Paola
Oktar, Rahime
Siano, Pierluigi
Cold ironing, which is the procedure of supplying shoreside electrical power to a ship at berth when its engines are turned off, arises as the eco-friendly way to deliver power to ships while they are berthed in ports, thus avoiding the use of diesel engines onboard, which provokes the emission of large amounts of greenhouse gases into the atmosphere. The aim of this study is twofold. Firstly, a survey of research developments on cold ironing is carried out in order to show the state of the art on the problem of greenhouse gases emitted by ships while docked and how to tackle it. Current regulations and examples of current ports that make use of technologies for cold ironing purposes are also shown. Secondly, the study proposes the use of a cold ironing system in the port of Barcelona, where the power generation is entirely given by renewable energy systems (wind turbines and photovoltaic panels). The idea is to contribute to the wide spread of cold ironing within smart port microgrids to achieve the goal of zero emissions from berthed ships.
A survey and evaluation of the potentials of distributed ledger technology for peer-to-peer transactive energy exchanges in local energy markets
Siano, Pierluigi
De Marco, Giuseppe
Rolán Blanco, Alejandro
Loia, Vincenzo
http://hdl.handle.net/2117/190876
2021-09-30T00:33:28Z
2020-06-16T12:18:03Z
A survey and evaluation of the potentials of distributed ledger technology for peer-to-peer transactive energy exchanges in local energy markets
Siano, Pierluigi; De Marco, Giuseppe; Rolán Blanco, Alejandro; Loia, Vincenzo
Theunpredictability and intermittency introduced by Renewable Energy Sources (RESs) in power systems may lead to unforeseen peaks of energy production, which might differ from energy demand. To manage these mismatches, a proper communication between prosumers (i.e., users with RESs that can either inject or absorb energy) and active users (i.e., users that agree to have their loads changed according to the system needs) is required. To achieve this goal, the centralized approach used in traditional power systems is no longer possible because both prosumers and active users would like to take part in energy transactions, and a decentralized approach based on transactive energy systems (TESs) and Peer-to-Peer (P2P) energy transactions should be adopted. In this context, the Distributed Ledger Technology (DLT), based on the blockchain concept arises as the most promising solution to enable smart contracts between prosumers and active users, which are safely guarded in blocks with cryptographic hashes. The aim of this paper is to provide a review about the deployment of decentralized TESs and to propose and discuss a transactive management infrastructure. In this context, the concept of Proof of Energy is proposed as a novel consensus protocol for P2P energy exchanges managed by DLT. An application of the proposed infrastructure considering a Virtual Power Plant (VPP) aggregator and residential prosumers endowed with a new transactive controller to manage the electrical storage system is discussed.
2020-06-16T12:18:03Z
Siano, Pierluigi
De Marco, Giuseppe
Rolán Blanco, Alejandro
Loia, Vincenzo
Theunpredictability and intermittency introduced by Renewable Energy Sources (RESs) in power systems may lead to unforeseen peaks of energy production, which might differ from energy demand. To manage these mismatches, a proper communication between prosumers (i.e., users with RESs that can either inject or absorb energy) and active users (i.e., users that agree to have their loads changed according to the system needs) is required. To achieve this goal, the centralized approach used in traditional power systems is no longer possible because both prosumers and active users would like to take part in energy transactions, and a decentralized approach based on transactive energy systems (TESs) and Peer-to-Peer (P2P) energy transactions should be adopted. In this context, the Distributed Ledger Technology (DLT), based on the blockchain concept arises as the most promising solution to enable smart contracts between prosumers and active users, which are safely guarded in blocks with cryptographic hashes. The aim of this paper is to provide a review about the deployment of decentralized TESs and to propose and discuss a transactive management infrastructure. In this context, the concept of Proof of Energy is proposed as a novel consensus protocol for P2P energy exchanges managed by DLT. An application of the proposed infrastructure considering a Virtual Power Plant (VPP) aggregator and residential prosumers endowed with a new transactive controller to manage the electrical storage system is discussed.
Doubly fed induction generator-based variable-speed wind turbine: proposal of a simplified model under a faulty grid with short-duration faults
Rolán Blanco, Alejandro
Pedra Durán, Joaquim
http://hdl.handle.net/2117/190873
2020-10-09T10:46:36Z
2020-06-16T12:11:50Z
Doubly fed induction generator-based variable-speed wind turbine: proposal of a simplified model under a faulty grid with short-duration faults
Rolán Blanco, Alejandro; Pedra Durán, Joaquim
The aim of this study is to provide a simplified model of a variable-speed wind turbine (VSWT) with the technology of a doubly-fed induction generator (DFIG) which operates under faulty grid conditions. A simplified model is proposed, which consists of a set of electrical and mechanical equations that can be easily modeled as simplistic electrical circuits. It makes it an excellent tool to achieve fault ride-through capability of grid-connected VSWT with DFIGs. Both symmetrical and unsymmetrical grid faults, which cause symmetrical and unsymmetrical voltage sags, have been applied to the system in order to validate the model. The proposed simplified model has been compared with the traditional full-order model under multiple sags (different durations and depths), and the results reveal that both models present similar accuracy. As the idea is to reduce the computational time required to simulate the machine behavior under faulty grid conditions, the proposed model becomes suitable for that purpose. The analytical study has been validated by simulations carried out with MATLAB.
2020-06-16T12:11:50Z
Rolán Blanco, Alejandro
Pedra Durán, Joaquim
The aim of this study is to provide a simplified model of a variable-speed wind turbine (VSWT) with the technology of a doubly-fed induction generator (DFIG) which operates under faulty grid conditions. A simplified model is proposed, which consists of a set of electrical and mechanical equations that can be easily modeled as simplistic electrical circuits. It makes it an excellent tool to achieve fault ride-through capability of grid-connected VSWT with DFIGs. Both symmetrical and unsymmetrical grid faults, which cause symmetrical and unsymmetrical voltage sags, have been applied to the system in order to validate the model. The proposed simplified model has been compared with the traditional full-order model under multiple sags (different durations and depths), and the results reveal that both models present similar accuracy. As the idea is to reduce the computational time required to simulate the machine behavior under faulty grid conditions, the proposed model becomes suitable for that purpose. The analytical study has been validated by simulations carried out with MATLAB.
Initialization of DFIG wind turbines with a phasor-based approach
Rolán Blanco, Alejandro
Pedra Durán, Joaquim
http://hdl.handle.net/2117/190872
2020-10-09T11:32:25Z
2020-06-16T12:08:23Z
Initialization of DFIG wind turbines with a phasor-based approach
Rolán Blanco, Alejandro; Pedra Durán, Joaquim
The objective of this paper is to propose a simple approach to solve the steady state of a wind turbine (WT) equipped with a doubly-fed induction generator (DFIG) which can be used to initialize dynamic studies of the machine. The idea is to model the rotor-side converter (RSC) as a constant current source connected to the rotor of the DFIG. The resulting equivalent circuit consists of a voltage source in series with a reactance, which makes it possible to obtain simple phasor expressions that can be used to obtain the Park components of the variables. The proposed method is compared with the traditional Newton-Raphson algorithm, showing that it is easier and faster to implement, as it makes use of the phasor expressions and it does not require an iterative process to obtain the final solution. Finally, the results of the proposed method are used to simulate a 2 MW DFIG-based WT under three-phase faults, considering three different WT operating points. In these simulations, the idea of constant rotor current is extrapolated to the entire event. The simulated results show that both current at torque peaks are reduced. The analytical study and the simulations have been carried out in MATLAB.
2020-06-16T12:08:23Z
Rolán Blanco, Alejandro
Pedra Durán, Joaquim
The objective of this paper is to propose a simple approach to solve the steady state of a wind turbine (WT) equipped with a doubly-fed induction generator (DFIG) which can be used to initialize dynamic studies of the machine. The idea is to model the rotor-side converter (RSC) as a constant current source connected to the rotor of the DFIG. The resulting equivalent circuit consists of a voltage source in series with a reactance, which makes it possible to obtain simple phasor expressions that can be used to obtain the Park components of the variables. The proposed method is compared with the traditional Newton-Raphson algorithm, showing that it is easier and faster to implement, as it makes use of the phasor expressions and it does not require an iterative process to obtain the final solution. Finally, the results of the proposed method are used to simulate a 2 MW DFIG-based WT under three-phase faults, considering three different WT operating points. In these simulations, the idea of constant rotor current is extrapolated to the entire event. The simulated results show that both current at torque peaks are reduced. The analytical study and the simulations have been carried out in MATLAB.
Analysis of the performance of MMC under fault conditions in HVDC-based off-shore wind farms
Vidal-Albalate, Ricardo
Beltran, Héctor
Rolán Blanco, Alejandro
Belenguer Balaguer, Enrique Francisco
Peña, Rubén
Blasco-Giménez, Ramón
http://hdl.handle.net/2117/190870
2020-10-09T10:28:57Z
2020-06-16T11:59:32Z
Analysis of the performance of MMC under fault conditions in HVDC-based off-shore wind farms
Vidal-Albalate, Ricardo; Beltran, Héctor; Rolán Blanco, Alejandro; Belenguer Balaguer, Enrique Francisco; Peña, Rubén; Blasco-Giménez, Ramón
This paper analyzes the behavior of a modular multilevel converter-high-voltage direct-current (MMC HVDC)-connected offshore wind power plant (WPP) during dc faults. For that purpose, detailed models of the dc cable, MMC stations, and transformers have been used in order to obtain reliable results. The influence of the WPP control method in the short-circuit behavior of the HVDC link has also been studied. Results show that the dynamics of the WPP contribution to pole-to-ground faults are slightly slower than those of the wind turbines current control loops. Therefore, the wind turbine front-end converters can be used to reduce the peak and average value of the fault current in such a system. Moreover, it has been found that ferroresonant oscillations can appear in the offshore ac grid when the WPP delivers constant power during faults.
2020-06-16T11:59:32Z
Vidal-Albalate, Ricardo
Beltran, Héctor
Rolán Blanco, Alejandro
Belenguer Balaguer, Enrique Francisco
Peña, Rubén
Blasco-Giménez, Ramón
This paper analyzes the behavior of a modular multilevel converter-high-voltage direct-current (MMC HVDC)-connected offshore wind power plant (WPP) during dc faults. For that purpose, detailed models of the dc cable, MMC stations, and transformers have been used in order to obtain reliable results. The influence of the WPP control method in the short-circuit behavior of the HVDC link has also been studied. Results show that the dynamics of the WPP contribution to pole-to-ground faults are slightly slower than those of the wind turbines current control loops. Therefore, the wind turbine front-end converters can be used to reduce the peak and average value of the fault current in such a system. Moreover, it has been found that ferroresonant oscillations can appear in the offshore ac grid when the WPP delivers constant power during faults.
Voltage sag influence on controlled three-phase grid-connected inverters according to the Spanish grid code
Bakkar, Mostafa
Bogarra Rodríguez, Santiago
Rolán Blanco, Alejandro
Córcoles López, Felipe
Saura Perisé, Jaime
http://hdl.handle.net/2117/186794
2022-03-20T06:21:23Z
2020-05-08T09:28:10Z
Voltage sag influence on controlled three-phase grid-connected inverters according to the Spanish grid code
Bakkar, Mostafa; Bogarra Rodríguez, Santiago; Rolán Blanco, Alejandro; Córcoles López, Felipe; Saura Perisé, Jaime
To ensure the safe operation of the grid, there are some requirements to be taken into consideration to connect power converters. During abnormal conditions – e.g. during voltage sags –, the control of the converters is a very important key to guarantee power quality and good behaviour of the distributed generation system. The aim of this study is to employ two possible control strategies for a grid-connected inverter according to the Spanish grid code, and to analyse the behaviour of the output voltages during both symmetrical and unsymmetrical voltage sags. The analytical development shows the sag influence on currents, voltages, active and reactive powers. These influences are explained through Ku transformation in the synchronous reference frame, thus giving a representation for electrical variables easiest to analyse. The results show how control strategies affect the converter behaviour and how they can support the main grid during faults through the control of active and reactive power injection. Sags with different durations and depths have been taken into account, which can provoke critical values for electrical magnitudes and can lead to the violation of the grid code. The proposed control strategies study has been validated by means of both simulations in MatlabTM–Simulink and experimental results
© 2020 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting /republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works
2020-05-08T09:28:10Z
Bakkar, Mostafa
Bogarra Rodríguez, Santiago
Rolán Blanco, Alejandro
Córcoles López, Felipe
Saura Perisé, Jaime
To ensure the safe operation of the grid, there are some requirements to be taken into consideration to connect power converters. During abnormal conditions – e.g. during voltage sags –, the control of the converters is a very important key to guarantee power quality and good behaviour of the distributed generation system. The aim of this study is to employ two possible control strategies for a grid-connected inverter according to the Spanish grid code, and to analyse the behaviour of the output voltages during both symmetrical and unsymmetrical voltage sags. The analytical development shows the sag influence on currents, voltages, active and reactive powers. These influences are explained through Ku transformation in the synchronous reference frame, thus giving a representation for electrical variables easiest to analyse. The results show how control strategies affect the converter behaviour and how they can support the main grid during faults through the control of active and reactive power injection. Sags with different durations and depths have been taken into account, which can provoke critical values for electrical magnitudes and can lead to the violation of the grid code. The proposed control strategies study has been validated by means of both simulations in MatlabTM–Simulink and experimental results
Voltage recovery influence on three-phase grid-connected inverters under voltage sags
Rolán Blanco, Alejandro
Giménez, Pablo
Yague, Sauro J.
Bogarra Rodríguez, Santiago
Saura Perisé, Jaime
Bakkar, Mostafa
http://hdl.handle.net/2117/131082
2022-03-20T06:18:00Z
2019-04-01T15:52:00Z
Voltage recovery influence on three-phase grid-connected inverters under voltage sags
Rolán Blanco, Alejandro; Giménez, Pablo; Yague, Sauro J.; Bogarra Rodríguez, Santiago; Saura Perisé, Jaime; Bakkar, Mostafa
Faults in power systems cause voltage sags, which, in turn, provoke large current peaks in grid-connected equipment. Then, a complete knowledge of the inverter behaviour is needed to meet fault ride-through capability. The aim of this paper is to propose a mathematical model that describes the behaviour of the currents that a three-phase inverter with RL filter inject to a faulty grid with symmetrical and unsymmetrical voltage sags. The voltage recovery process is considered, i.e., the fault is assumed to be cleared in the successive zero-cross instants of the fault current. It gives rise to a voltage recovery in different steps (discrete voltage sag), which differs from the usual model in the literature, where the voltage recovers instantaneously (abrupt voltage sag). The analytical model shows that the fault-clearing process has a strong influence on the injected currents. Different sag durations and depths have also been considered, showing that there exist critical values for these magnitudes, which provoke the highest current peaks. The analytical study is validated through simulations in MATLAB and through experimental results
2019-04-01T15:52:00Z
Rolán Blanco, Alejandro
Giménez, Pablo
Yague, Sauro J.
Bogarra Rodríguez, Santiago
Saura Perisé, Jaime
Bakkar, Mostafa
Faults in power systems cause voltage sags, which, in turn, provoke large current peaks in grid-connected equipment. Then, a complete knowledge of the inverter behaviour is needed to meet fault ride-through capability. The aim of this paper is to propose a mathematical model that describes the behaviour of the currents that a three-phase inverter with RL filter inject to a faulty grid with symmetrical and unsymmetrical voltage sags. The voltage recovery process is considered, i.e., the fault is assumed to be cleared in the successive zero-cross instants of the fault current. It gives rise to a voltage recovery in different steps (discrete voltage sag), which differs from the usual model in the literature, where the voltage recovers instantaneously (abrupt voltage sag). The analytical model shows that the fault-clearing process has a strong influence on the injected currents. Different sag durations and depths have also been considered, showing that there exist critical values for these magnitudes, which provoke the highest current peaks. The analytical study is validated through simulations in MATLAB and through experimental results
Modeling and control of a three-phase grid-connected inverter under fault conditions
Rolán Blanco, Alejandro
Giménez, Pablo
Yague, Sauro J.
Bogarra Rodríguez, Santiago
http://hdl.handle.net/2117/123223
2020-10-09T11:31:57Z
2018-10-30T11:10:08Z
Modeling and control of a three-phase grid-connected inverter under fault conditions
Rolán Blanco, Alejandro; Giménez, Pablo; Yague, Sauro J.; Bogarra Rodríguez, Santiago
The aim of this paper is to study the behavior of a three-phase inverter with an RL filter powered by a renewable energy source and connected to a grid under fault conditions. The novelty of the work lies in proposing a mathematical model which can be solved analytically. So, a comprehensive analytical solution is given, which can be used to describe the behavior of a three-phase inverter under both symmetrical and unsymmetrical faults. Firstly, a complete mathematical model of the system is given. Secondly, a control is applied for both symmetrical (three-phase faults) and unsymmetrical (one-phase and two-phase faults) conditions, making use of the positive- and negative-sequence components for the latter. Finally, a mathematical model for the whole system Is developed. The analytical approach is valid for any fault conditions, either symmetrical or unsymmetrical, which helps in the understanding of the behavior of three-phase inverters connected to a faulty grid and simplifies its study. The analytical model is validated through simulations carried out in Matlab-simulink™.
©2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.
2018-10-30T11:10:08Z
Rolán Blanco, Alejandro
Giménez, Pablo
Yague, Sauro J.
Bogarra Rodríguez, Santiago
The aim of this paper is to study the behavior of a three-phase inverter with an RL filter powered by a renewable energy source and connected to a grid under fault conditions. The novelty of the work lies in proposing a mathematical model which can be solved analytically. So, a comprehensive analytical solution is given, which can be used to describe the behavior of a three-phase inverter under both symmetrical and unsymmetrical faults. Firstly, a complete mathematical model of the system is given. Secondly, a control is applied for both symmetrical (three-phase faults) and unsymmetrical (one-phase and two-phase faults) conditions, making use of the positive- and negative-sequence components for the latter. Finally, a mathematical model for the whole system Is developed. The analytical approach is valid for any fault conditions, either symmetrical or unsymmetrical, which helps in the understanding of the behavior of three-phase inverters connected to a faulty grid and simplifies its study. The analytical model is validated through simulations carried out in Matlab-simulink™.
Testing of three-phase equipment under voltage sags
Rolán Blanco, Alejandro
Córcoles López, Felipe
Pedra Durán, Joaquim
Monjo Mur, Lluís
Bogarra Rodríguez, Santiago
http://hdl.handle.net/2117/79313
2021-10-24T08:02:32Z
2015-11-16T13:24:24Z
Testing of three-phase equipment under voltage sags
Rolán Blanco, Alejandro; Córcoles López, Felipe; Pedra Durán, Joaquim; Monjo Mur, Lluís; Bogarra Rodríguez, Santiago
This paper provides insight into the testing of three-phase equipment exposed to voltage sags caused by faults.
The voltage sag recovers at the fault-current zeros, leading to a ‘discrete’ voltage recovery, that is, the fault is cleared in
different steps. In the literature, the most widespread classification divides ‘discrete’ sags into 14 types. The authors study shows that it is generally sufficient to consider only five sag types for three-phase equipment, here called ‘time-invariant
(TI)’ equipment. As the remaining nine sag types cause identical equipment behaviour in Park or Ku variables, the number of laboratory tests (or of extensive simulations) on equipment under sags is reduced by a ratio of 14/5. The study is validated by simulation of a three-phase induction generator and a three-phase inverter, which are ‘TI’, and a threephase
diode bridge rectifier, which is not ‘TI’. Both analytical study and simulation results are validated by testing a three-phase induction motor and a three-phase diode bridge rectifier.
2015-11-16T13:24:24Z
Rolán Blanco, Alejandro
Córcoles López, Felipe
Pedra Durán, Joaquim
Monjo Mur, Lluís
Bogarra Rodríguez, Santiago
This paper provides insight into the testing of three-phase equipment exposed to voltage sags caused by faults.
The voltage sag recovers at the fault-current zeros, leading to a ‘discrete’ voltage recovery, that is, the fault is cleared in
different steps. In the literature, the most widespread classification divides ‘discrete’ sags into 14 types. The authors study shows that it is generally sufficient to consider only five sag types for three-phase equipment, here called ‘time-invariant
(TI)’ equipment. As the remaining nine sag types cause identical equipment behaviour in Park or Ku variables, the number of laboratory tests (or of extensive simulations) on equipment under sags is reduced by a ratio of 14/5. The study is validated by simulation of a three-phase induction generator and a three-phase inverter, which are ‘TI’, and a threephase
diode bridge rectifier, which is not ‘TI’. Both analytical study and simulation results are validated by testing a three-phase induction motor and a three-phase diode bridge rectifier.