Model based control algorithms for a secure integration of distributed generation into microgrids
- Authors
- Minchala ?vila, Luis Ismael
- Format
- DoctoralThesis
- Status
- publishedVersion
- Description
The prosperity of smart grids related technology nowadays at industrial and scienti c/academic levels is noticeable and undoubtedly the topic is a hot spot in research and development. The technology that demands immediate attention due to the advent of energy shortage problems is microgrids technology, since it constitutes a feasible solution to these problems. Microgrids operation lack of well-established standards and the need for their development has fostered signi cant research and development activities in this eld. This thesis focuses in the design and development of model-based and optimal, non-classic control algorithms, to be applied in the operation of microgrids. The aim of these control strategies is to guarantee a secure operation of microgrids when they operate in islanded mode. The thesis studies problems related with frequency and voltage regulation of microgrid generation units, as well as optimal load shedding decisions for balancing local power generation and load. A centralized control algorithm is implemented in a simulation platform generated in Simulink for ensuring a secure islanded microgrid operation when power system stability may be a ected by imbalances between generation and load. A nonlinear model predictive control (NMPC) algorithm is selected for processing measurements of the batteries state of charge, the renewable energy sources active power generation, and the forecasted load. The algorithm predicts the microgrid response of selected state variables, which are used to identify upcoming active power unbalances and to initiate automated load shedding applied to non-critical loads. The control strategy guarantees a stable microgrid operation, while covering prioritized load demand. The control strategy is tested in a medium voltage distribution system with distributed generation (DG) units modeled in a simulation environment developed in MATLAB. A hierarchical control strategy is designed, which lower layer is ful lled with distributed controllers to control DG. Two model-based distributed controllers were designed to control the DG units: a model predictive control (MPC) and a model reference adaptive control (MRAC). Fault-tolerant control (FTC) techniques were used for designing an adequate control strategy to integrate a diesel engine generator (DEG) as the master generation unit controlling voltage and frequency, in an islanded microgrid. The control algorithms developed in this research project are tested and compared with classic control techniques and open-loop operating conditions in order to evaluate the performance improvement achieved with the use of these control strategies, which increase microgrid reliability by maintaining the balance between generation and load, and by providing fault-tolerant microgrid operation.
- Publication Year
- 2014
- Language
- eng
- Topic
- INGENIER?A DE CONTROL
REDES EL?CTRICAS INTELIGENTES
MODEL BASED CONTROLLER
SMART GRIDS
- Repository
- Repositorio SENESCYT
- Rights
- openAccess
- License