Scheduling And Planning Methods Of Community Integrated Energy Systems For Flexible And Reliable Operation

With the primary energy depletion and increasing environmental pollution all around the world,it is of great importance to develop and utilize renewable energy,as well as improve the efficiency and cleanliness of user-side energy consumption.Community integrated energy system(CIES)couples multiple energy systems and can realize high efficiency utilization,and is a promising means to realize sustainable development and clean energy substitution.CIES contains multiple energy forms.The supply,distribution and consumption are highly coupled,making the operation behaviors more complex.In order to realize the efficient and reliable operation of CIES,it is necessary to develop reasonable and effective operating and planning methods.This dissertation focuses on the key issues of optimal operation and planning of CIES for different requirements and application scenarios.The main contributions are summarized as follows:1)For the economic scheduling problem,the economic scheduling strategy and corresponding tie-lie power smoothing method of CIES are proposed with consideration of the unit commitment constraints and energy storage's flexibilities.After building detailed models of energy supply and thermal storage devices,a mixed-integer linear programming-based day-ahead scheduling strategy is proposed,which takes into account multiple energy demands,multiple energy conversion links and multiple energy supply methods.Electricity is set as the core energy and the goal is to minimize the operating cost and the on-off penalty of the devices.The unit commitment constraints in practical operation and the flexibilities of energy storage devices are fully considered;thus the startup/shutdown frequency is significantly decreased and the energy efficiency and economic performance are improved.Considering the peak-valley difference requirements of the distribution system operator(DSO),a scheduling model for the tie-line power smoothing is also proposed.Thus,the peak-valley difference of tie-line power is decreased and the fluctuations are suppressed.2)Considering the uncertainties of distributed generation outputs,loads and environmental factors,the model predictive control(MPC)based multiple time-scale scheduling strategy and robust scheduling strategy considering multiple links' flexibilities are proposed.The proposed MPC-based multiple time-scale scheduling strategy includes the rolling optimization stage of large time-scale and dynamic adjustment stage of small time-scale.The uncertainties of renewable resources and loads with various time-scale are well adapted.Additionally,an MPC-based robust scheduling method with the integration of multiple links' flexibilities is proposed.The source-network-load rolling economic dispatch model integrates the operation of central energy station,the pipelines' dynamic transfer characteristics and buildings' storage characteristics;and it can fully utilize the flexibilities of different links while improving the adaptability to forecasting uncertainties.The uncertainties of the environmental factors are quantified and the robust schedule can be generated by the adjustable margins' reservation.Thus,the real-time forecasting errors of environmental factors can be well accommodated.3)To satisfy the resilient requirements of energy systems,the scheduling and planning methods which consider the operational resilience of integrated electricity and gas energy system(IEGS)are proposed.For the IEGS that contains multiple energy inputs,the resilience scheduling strategy considering the storage reserve is proposed based on the complementary coordination and reservation of the devices driven by different energies.The thermal storage devices are used as emergency response resources to support the critical loads in case of failures.And the ability to cope with the source outages is improved.Meanwhile,the sensitivity analysis of the outage and critical loads' parameters is also carried out.Furthermore,a two-level planning method that integrates the resilient operation is developed.Through the optimization iteration with genetic algorithm in the upper level and the resilience scheduling strategy in the lower level,the configuration scheme that can effectively adapt to gas and electricity outages in actual operation is obtained.