logoGlobal Energy Interconnection
  • Data-driven resilience analysis of power grids

    2021-03-15

    Qicong Sun, Yan Li, Jason Philhower

    2021, 4(1): 104-114 pdf html

    With the integration of renewable energy resources,the inertia of power systems significantly reduces,thereby making the system sensitive to operational disturbances.A disturbance-based method is presented herein to estimate inertia,uncovering the influence of renewables on system-resilient operations.The Gaussian process regression method is then used to predict the power system trajectory after disturbance.Extensive tests demonstrate the data-driven method mathematically estimates the inertia of the system as well as predicts the dynamics operations of power grids subject to disturbances.Numerical results also offer insights into the enhancement of system resilience by strategically designing the inertia of power systems.

    more
  • Key technologies for medium and low voltage DC distribution system

    2021-03-15

    Yiwen Fan, Yongning Chi, Yan Li, Zhibing Wang, Hongzhi Liu, Wei Liu, Xiangyu Li

    2021, 4(1): 91-103 pdf html

    Development of the medium and low voltage DC distribution system is of great significance to a regional transmission of electric energy,increasing a penetration rate of new energy,and enhancing a safety of the operation of the AC/DC interconnected grid.This paper first summarizes the medium and low voltage DC distribution system schemes and plans put forward by many countries,and then elaborate status of under-construction medium and low voltage DC distribution system project cases in China.Based on these project cases,this paper analyzes key issues involved in the medium and low voltage DC distribution system topologies,equipment,operation control technologies and DC fault protections,in order to provide theoretical and technical reference for future medium and low voltage DC distribution system-related projects.Finally,this paper combines a current China research status to summarize and give a prediction about the future research direction of medium and low voltage DC distribution system,which can provide reference for the research of medium and low voltage DC distribution system.

    more
  • Multi-objective partition planning for multi-infeed HVDC system

    2021-03-15

    Zhao Yu, Shuanbao Niu, Chao Huo, Ning Chen, Kaige Song, Xiaohui Wang, Yu Bai

    2021, 4(1): 81-90 pdf html

    The close proximity and the necessity of coordination between multiple high-voltage direct currents (HVDCs) raise the issue of grid partitioning in multi-infeed HVDC systems.A multi-objective partition strategy is proposed in this paper.Several types of relationships to be coordinated and complemented are analyzed and formulated using quantitative indices.According to the graph theory,the HVDC partition is transformed into a graph-cut problem and solved via the spectral clustering algorithm.Finally,the proposed method is validated for a practical multi-HVDC grid,confirming its feasibility and effectiveness.

    more
  • Power system planning with high renewable energy penetration considering demand response

    2021-03-15

    Peng Wang, Ershun Du, Ning Zhang, Xinzhi Xu, Yi Gao

    2021, 4(1): 69-80 pdf html

    Electric system planning with high variable renewable energy (VRE) penetration levels has attracted great attention world-wide.Electricity production of VRE highly depends on the weather conditions and thus involves large variability,uncertainty,and low-capacity credit.This gives rise to significant challenges for power system planning.Currently,many solutions are proposed to address the issue of operational flexibility inadequacy,including flexibility retrofit of thermal units,inter-regional transmission,electricity energy storage,and demand response (DR).Evidently,the performance and the cost of various solutions are different.It is relevant to explore the optimal portfolio to satisfy the flexibility requirement for a renewable dominated system and the role of each flexibility source.In this study,the value of diverse DR flexibilities was examined and a stochastic investment planning model considering DR is proposed.Two types of DRs,namely interrupted DR and transferred DR,were modeled.Chronological load and renewable generation curves with 8760 hours within a whole year were reduced to 4 weekly scenarios to accelerate the optimization.Clustered unit commitment constraints for accommodating variability of renewables were incorporated.Case studies based on IEEE RTS-96 system are reported to demonstrate the effectiveness of the proposed method and the DR potential to avoid energy storage investment.

    more
  • The IES dynamic time-scale scheduling strategy based on multiple load forecasting errors

    2021-03-15

    Fan Sun, Ran Li, Yi Han, Shouang Liu, Fanrui Liu, Huilan Liu

    2021, 4(1): 58-68 pdf html

    Considering the complex coupling of multiple energies and the varying load forecasting errors for an integrated energy system (IES),this study proposes a dynamic time-scale scheduling strategy based on long short-term memory (LSTM)and multiple load forecasting errors.This strategy dynamically selects a hybrid timescale which is suitable for a variety of energies for each month.This is obtained by combining the mean absolute percentage error (MAPE) curve of the load forecasting with the error restriction requirements of the dispatcher.Based on the day-ahead scheduling plan,the output of the partial equipment is selectively adjusted at each time-scale to realize multi-energy collaborative optimization and gives full play to the comprehensive advantages of the IES.This is achieved by considering the differences in the response speed for each piece of equipment within the intra-day scheduling.This study uses the IES as an example,and it dynamically determines the time scale of the energy monthly.In addition,this investigation presents a detailed analysis of the output plan of the key equipment to demonstrate the necessity and the advantages of the strategy.

    more
|<< Previous 1 2 3 4 5 6 7 8 9 ... Next >>|