MULTI-MICROGRIDS AS A SMART STRUCTURE Carlos Moreira Ciência 2010 –

INTRODUCTION Electric power systems are facing a change of paradigm On-line available:

MICROGRID: A SMART AND FLEXIBLE CELL OF THE ELECTRICAL POWER SYSTEM Micro Wind Generator Microturbine Fuel Cell Storage Device MGCC MC LC MG Hierarchical Control: MGCC, LC, MC Communication infrastructure

EVOLUTION OF THE MICROGRID CONCEPT New concept  Multi-Microgrids Requires a higher level structure, at the MV level, consisting of LV Microgrids and DG units connected on several adjacent MV feeders Microgrids, DG units and MV loads under DSM control can be considered as active cells, for the purpose of control and management An effective management of such a system requires the development of a hierarchical control architecture, where intermediate control will be exercised by a Central Autonomous Management Controller (CAMC) to be installed at the MV bus level of a HV/MV substation

CONTROL SCHEME OF A MULTI-MICROGRID SYSTEM Use of a Decentralized and Hierarchical Control Scheme Autonomy vs. Coordination

CONTROL SCHEME OF A MULTI-MICROGRID SYSTEM Existing DMS functionalities need to be adapted to Multi-MicroGrid operation The management of the Multi-MicroGrid will be performed through the CAMC using an Hierarchical Control Architecture, which required the development of important functionalities: The Multi-MicroGrid allows the intelligent integration of all the players connected to it – both costumers and DG –in order to efficiently improve electricity supply

THE ESSENCE OF THE SMART GRID SmartGrids: exploiting DER (DG+loads) value

SMART GRID: TOWARDS A REAL IMPLEMENTATION INOVGRID vs Multi-MicroGrid InovGrid project will provide the communication and control infrastructure to enable the implementation of the smart grid concept

COORDINATED VOLTAGE SUPPORT IN A MULTI-MICROGRID High DG penetration may cause voltage rise problems, especially in the case of weak distribution networks The effects of voltage rise may propagate to the LV side From the power flow equations (in LV networks where R<<X): In conclusion, high DG and microgeneration penetration will require the development of an effective voltage control scheme based on active and reactive power control

COORDINATED VOLTAGE SUPPORT IN A MULTI-MICROGRID DIMENSION AND COMPLEXITY

COORDINATED VOLTAGE SUPPORT IN A MULTI-MICROGRID DIMENSION AND COMPLEXITY

COORDINATED VOLTAGE SUPPORT IN A MULTI-MICROGRID DIMENSION AND COMPLEXITY

COORDINATED VOLTAGE SUPPORT IN A MULTI-MICROGRID In order to maintain voltage profiles within admissible limits, Microgeneration Shedding was required A Neural Network was used to emulate the behavior of the LV MicroGrid Global Approach Optimizing distribution network operation in interconnected mode, when dealing simultaneously with DG connected directly to the MV grid and microgeneration installed at the LV side Controls: OLTC Transformer taps Reactive power provided by DG Sources and Capacitor Banks Active power control at the MicroGrid level in extreme scenarios (using Microgeneration Shedding)

COORDINATED FREQUENCY SUPPORT CHP MicroGrid Hydro DFIM VSI TEST SYSTEM

COORDINATED FREQUENCY SUPPORT Frequency Deviation following Islanding of the Multi-MicroGrid System Active Power Set-Points sent by the CAMC to the DG Units and MicroGrids Local secondary frequency control was designed such that load shedding is also managed

FINAL REMARKS The main issues to be dealt within the future are the deployment of Smart Metering as a mean of pushing forward the development of MicroGrids (MG) as an integrated part of the general Smart Grid concept Integrated management of MicroGrids allows the integration of flexible DG, flexible consumption (including EV battery charging – smart charging) and flexible storage.  Flexibility A full assessment of active demand side management strategies (managed by the DSO) should also be carried out Regulatory issues need to further addressed (quantity of needed flexibility and value of flexibility) for system operation in normal and emergency modes

PROJECTS AND RESEARCH TEAMS MICROGRIDS – Large scale integration of microgeneration in low voltage grids ( EU FP5) Coordinator: Professor João Peças Lopes Professor Manuel Matos Doctor João Paulo Tomé Saraiva PhD Student Carlos Moreira PhD Student André Madureira PhD Student Fernanda Resende Luís Seca InovGrid (Contracted by EDP Distribuição – …) Coordinator: Professor Doutor João Peças Lopes Doctor Carlos Moreira Doctor Nuno Fidalgo Doctor José Rui Ferreira Doctor Nuno Gil PhD Student Pedro Almeida PhD Student Filipe Joel Soares Luís Seca Pedro Barbeiro MORE MICROGRIDS – Advanced architectures and control concepts for More Microgrids ( EU FP6) Coordinator: Professor João Peças Lopes Professor Manuel Matos Doctor João Paulo Tomé Saraiva PhD Student Carlos Moreira PhD Student André Madureira PhD Student Fernanda Resende PhD Student Nuno Gil PhD Student Julija Vasiljevska Luís Seca TWENTIES – Transmission system operation with large penetration of Wind and other renewable Electricity sources in Networks by means of innovative Tools and Integrated Energy Solutions (2010 – 2013 EU FP7) Coordinator: Doctor Carlos Moreira Professor João Peças Lopes Doctor Fernanda Resende Phd Student Bernardo Silva

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