The Research On Digital Simulation Method And Development Of Load Modeling System For Microgrid

Digital simulation is the most commonly method to study the static and dynamicbehavior of power system, it has become an indispensable tool of power systemresearch and engineering fields. Besides, simulation technology is also an importantresearch tool for distributed generation system and microgrid system. TheMeasurement-based load modeling strictly uses input-output data of research objectsas the basis, again determines the mathematical model and parameters of the loadaccording to the system identification theory. Given the complexity of the microgridsystem and engineering application status of microgrid and distributed generationtechnologies, with the limitations of the actual conditions, there are few examples ofmicrogrid operation and less experimental data for reference at present. In addition,there are great difficulties to obtain project site operational or experimental data ofthe distribution network with a certain scale distributed generation system. Therefore,the research on digital simulation method of distribution network with microgrid anddistributed generation system, the development of digital simulation and modelingsystem of distribution network with microgrid and distributed power have importanttheoretical and practical significance.This paper has analyzed and described the main technology and implementationmethods of necessary for the visualization software design on the basis of a briefoverview of development and research status of microgrid and characteristics andrequirements of synthesis load modeling with distributed power. Besides, it hasproposed design ideas, construction principle, the basic structure and functionalrequirements of the digital simulation and load modeling system for microgrid. Thenagain, it has developed a digital simulation and load modeling system for distributionnetwork with microgrid and distributed power.This system was developed with object-oriented programming languages andvisual programming technology based on the Windows environment. Each databaseand functional modules were integrated into a whole organically through the use ofmodular software design and a variety of interface technologies. Moreover, the frontoperation interface of this system has adopted graphic user interface (Graphic UserInterface, GUI) based on Matlab, the back-end database server has taken SQL Server2000, altogether with M and VC++as programming language while using the open database connectivity (Open Database Connectivity, ODBC) to achieve the connectionbetween Matlab and database, using ADO (ActiveX Data Objects) database accessinterface technology to achieve the VC++recognition program to access the database,using ActiveX controls to achieve Matlab operating on VC++recognition program.This system has four functions: Firstly, library operation with different types ofdistributed power and other network components, such as build and packagecomponent model, add, modify and delete the components. In the second place,system simulation experiment, such as building simulation system, transientsimulation experiments under the conditions of steady state and fault disturbance,query and display the experimental results. Furthermore, data processing, such asprocessing simulation data into a data sample for identification modeling, engineeringfield measured data import, data query, display and management. At last, theMeasurement-based load modeling, such as data sample, model structure andidentification algorithm selection, model parameter identification, graphical displayof the identification results and the model parameter database management. Given itsadvantages of opening source code, strong extensibility, unique design, reliable andsimple operation, this system is to provide a good experimental research platform forstudying the impact of microgrid and distributed power on comprehensive loadcharacteristics of distribution network.