Hierarchical Control And Operation Optimization For Multi-energy Complementary Microgrid

With the transformation of national energy structure,the role of multi-energy complementary microgrid with high energy efficiency and high clean energy permeability is becoming more and more significant.On one hand,as an extension of microgrid,multi-energy complementary microgrid inherits the advantages of flexible operation and local consumption of microgrid,but also leaves over the problems about frequency of unbalanced power and difficulty in ensuring power quality caused by the intermittent output of microsource and load fluctuation.On the other hand,multi-energy complementary microgrid has multiple energy flow interactions which are making its control strategy more complex than traditional microgrid.According to the operational requirements and real-time requirements of multi-energy complementary microgrid,this thesis investigated the operational control strategy of multi-energy complementary microgrid that makes an overall planning for the operation mode of multi-energy complementary microgrid with three-layer control constructed,and proposed a new power quality optimization control scheme.Based on the interaction of cold,heat and power interaction,this thesis structured the structure of multi-energy complementary microgrid and established the simulation model of microsource.Aiming at the problem of microsource power distribution when load fluctuates,the underlying control strategy based on droop control is adopted.To solve the problem of microsource output prediction and planning,a second-layer optimal operation control strategy is constructed by using Particle Swarm Optimization algorithm with the objective of minimizing the combined operation and environmental protection cost.Focusing on the problem that power quality is not considered in operation and optimization control,a three-layer power quality optimization control strategy based on power optimization scheme with different weight proportions and comprehensive ranking by Data Envelopment Analysis is proposed.Simulation results of multi-energy complementary microgrid hierarchical control strategy show that the underlying control strategy based on droop control can realize the instantaneous power redistribution when the working condition changes on the basis of the rated power output,and as to meet the load requirements.The second-layer optimization control strategy can optimize the power of each micro-source and equipment under the constraints of cold,heat and electric power balance,as well as obtain the best economic and environmental protection indicators.The three-layer control optimizes the output power of each microsource according to different weight proportions to obtain better power quality.This thesis also established the multi-energy complementary microgrid semi-physical platform based on RTLAB and LabVIEW operation data monitoring platform.The foundation is established for further experimental verification.