Research On Construction And Operation Control Of RTLAB Based Multi-energy Complementary Microgrid

Due to the increasing shortage of the energy,the new energy power generation has been widely studied,in which the proportion of the clean energy is corresponding rising.Because the situation that large scale clean energy has been connected into the power grid,the number of consumption problem has significantly increased.Therefore,in order to solve the problem,the multi-energy complementary microgrid which has complementary characteristics came to emerge.This energy form has overcome randomness and intermittent impact of distributed power sources on the grid,as well as increases power supply reliability.When the multi-energy complementary microgrid switches between off-grid and heavy-duty switching,power shortages are easily prone to voltage and frequency fluctuations.Because there exist the large number of converters in the load,these non-linear loads generate a large amount of harmonic voltage which will affect the quality of the entire multi-energy complementary microgrid.Related to the national grid science and technology project "experimental microgrid planning,operation and platform demonstration considering multiple source-network-load flexible matching methods",this thesis studies the establishment of micro-source models and micro-source characteristics in detail,and builds a multi-energy complement the microgrid.On the basis of the experimental data of the existing micro-sources in the laboratory of Liaoning Electric Power Research Institute,the model is modified to be more accurate.Based on the complementary characteristics of cold and hot electric load,the large inertia of thermal cooling load in multi-energy complementary microgrid and the traditional electric heating control strategy,the energy balance control strategy of multi-energy complementary microgrid is designed.The simulation analysis of the multi-energy complementary microgrid with master-slave control.First,the multi-master-slave control structure which combines the advantages of master-slave control and peer-to-peer control is adopted to solve the problem of voltage and frequency fluctuation.Second,aiming at the traditional droop control strategy adopted by the dual-master micro-source,the voltage and frequency are subject to the fluctuation of the droop characteristic when the load is abrupt.The robust droop control strategy is adopted to stabilize the output voltage and frequency of the dual-master micro-source at 220 V.50Hz,which is to provide reference values from micro sources using P/Q control strategy accurately.Finally,facing the harmonic voltage generated by the nonlinear load,the harmonic droop control strategy is added,and combined with the robust droop control strategy.Besides that,the frequency-dividing droop control strategy is constructed to control the bus voltage and frequency fluctuation and harmonic voltage,which improves the power quality of multi-energy complementary microgrid systems.A small-signal model is constructed based on the control strategy and its stability is researched.Through the simulation experiment comparison,the control strategy is verified.Taking advantage of the semi-physical simulation platform RTLAB,the multiplexed complementary microgrid and control strategy run in real time,and the data of RTLAB is collected and analyzed by Audeli data acquisition system DEWE5000.