Adaptive Controls for Maintaining the Stability of Microgrid Operations

• Main Authors: Mohammed Ansar Mohammed Manaz, 艾慕明
• Other Authors: Chan-Nan Lu
• Format: Others
• Language: en_US
• Published: 2019
• Online Access: http://ndltd.ncl.edu.tw/handle/exrdws

博士 === 國立中山大學 === 電機工程學系研究所 === 107 === Microgrids are designed to ensure reliability and quality of power supply. Reliable islanding transition and stable operation of the ensuing island microgrid are key to maintaining an uninterrupted supply of power to critical loads. Current islanding transition schemes proposed in the literature assume the availability of fast response from local energy resources, like battery storage system, to establish secure islanding transition and subsequent islanded operation; however, such fast response systems are often expensive. Analysis of historical events shows that the islanding event, at most instances, can be predicted; by exploiting this feature, this thesis proposes an adaptive optimal defense mechanism to establish secure islanding, without necessarily requiring fast response energy resources. During the ensuing islanded operation, the renewable energy sources like solar PV and wind energy conversion system can provide dynamic frequency support to maintain the stability of the microgrid. Given the scarcity of resources in such islanded microgrids, suitable controls must be developed to optimally utilize these sources’ frequency support capability. An optimal frequency support service must minimize the magnitude of the rate of change of frequency, maximize the frequency nadir and quickly damp frequency oscillations to the nominal value subject to device level constraints. To this end, this thesis proposes new controllers for the solar PV and wind energy conversion systems to optimize their frequency support service. Simulation results are presented to demonstrate the performance of the proposed methods.