مدل سازي سيگنال كوچك ريزشبكه هاي تركيبي در حالت جزيره اي

چكيده انگليسي :

Small Signal Modeling of Hybrid Microgrids in Islanding Mode Navid Sedighiani n sedighiani@ec iut ac ir July 3 2019 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language Farsi Supervisors Javad Askari j askari@cc iut ac ir Mohammad Sadegh Golsorkhi golsorkhi@cc iut ac ir AbstractFrequency stability and stability of the grid voltages in the islands after an unusual event that leads to volatilityand frequency fluctuations in the grid is very important and crucial for the proper functioning of the grid Therefore the stability analysis of micro grids is of particular importance The stability analysis of conventionalpower systems is often done well but in grid networks it is necessary to check how the circuit functions control and how to dampen fluctuations to ensure the stability of the grid An appropriate mathematical modelis essential for sustainability analysis This dissertation presents modeling and stability analysis in the operatingstate of the islands of interconnecting interconnecting interconnecting and interconnecting micro grids Forthe modeling of all micro grids internal loop voltages and inverters and transducers are modeled in detailto observe all the modes of the grid for sustainability analysis For ease of modeling the overall system ofthe combined grid is divided into several subsections the subsystems of the system are modeled with state space equations and finally all sub sections are combined through the bases and the overall model of thecombined grid system is modeled in the form of state space equations In the general modeling of the system the bus voltages are used as a parameter for the connection of different micro grid components In modelingthe bus voltages a virtual strength is used to connect the meshes to any arbitrary structure Also in a grid ofdirect current from the Boost converter to increase the voltage level of the distributed generation source usedin previous work to facilitate system stability from the Buck converter Due to the existence of some modesof relatively high frequency inverters and converters the full dynamic network model is used instead of thealgebraic impedance model The complete model of the system is rooted around a work point and the final state matrix of the combined grid is used to extract special values Using the extracted values the stability ofthe combined grid system can be checked In addition to conducting system stability this study also identifiesthe relationship between system stability and system parameters such as controller gain in order to optimizethe efficiency of controllers Specific values or system modes indicate the frequency and rate of oscillationof component oscillations in the transient response of the system The stability analysis of the grid also helpsdefine the root of each mode and defines possible feedback signals for designing controllers to improve systemstability In the next simulation and modeling simulation a mixed mesh grid is presented that demonstrates thecorrect and stable performance of the combined grid Using the proposed model the stability analysis of thespecific values of the grid is done KeywordsHybrid Microgrid ac Microgrid dc Microgrid Modeling Stability Analysis

صديقياني، نويد

مدل سازي سيگنال كوچك ريزشبكه هاي تركيبي در حالت جزيره اي

ريزشبكه تركيبي , ريزشبكه ac , ريزشبكه dc , مدل سازي , تحليل پايداري