The Research On Control Technology Of Microgrid Based On Proportional Complex Integral Controller

Energy is the foundation for the development of socialty and economy,which has a direct impact on the social stability.With an extensive use of the fossil energies,those energy are facing exhaustion problems.Meanwhile,the environmental problems caused by the burning of fossil fuels have attracted much attention in the world.The electronic power is a secondhand energy which can be convertered from the firsthand energy such as fussil energy.However,it is recommended that the electronic power energy should not be highly independently on the fossil energy because of environmental problems and the exhaustion of fossil energy.Therefore,in order to ensure the normal running of the society,the electronic power should find a stable and sustainable development.Consequently,renewable energy power has become the inevitable choice for generating electronic power.Microgrid,which is an important part of energy interconnection and smart grid,can be treated as an interface between the main power system and distributed generation system.Therefore,studying the mircogrid has an important significance.Based on the operating requirements of the microgrid,the control technology of the converter has been mainly studied.And a power cross-coupling compensation control strategy is proposed.The main structure of the thesis can be simplified as follows.Firstly,the three-level control system hierarchy and the main control strategies of the microgrid have been introduced in the final of the introduction.Secondly,the operating method?modulation technology and the key control technologies of the converter have been clarified.The operating performance and the application of different drop controls have been analyzed based on the foundation of the primary drop control.The mechanisms of circulatingcurrent among the different distributed generaters have been clarified.The proportional complex integral(PCI)control strategy is proposed and selected as the main control strategy of the converter.Thirdly,the implement of the PCI control has been studied.The control structure of the proposed drop control strategy based on the power cross-coupling compensation control strategy has been designed.And the three-level closed loop control strategy of the power cross-coupling compensation control strategy designed for the microgrid has been obtained.Fourtly,considering the paralleled converters of microgrid with different line distance may be unstable under the traditional drop control when the microgrid runs into the inland operating stuts and the problems that traditional proportional integral(PI)controller can not realize the zeros steady state of AC quinities,a power cross-coupling compensation control strategy with PCI controller under ?? coordinate is proposed.This control strategy not ONLY can make the microgrid steady operated even with different line distances but also can obtain zeros steady state of the output AC voltage.Finally,the effectiveness of the proposed method is validated by using the MATLAB/simulink.