Study On Energy Management Strategy Of Combined Heating And Power Generation In Microgrid

With the development of renewable energy,combined heating and power unit(CHP unit),and energy storage technologies,the relationship between electricity and heat in production,transmission,and consunption is getting closer.More and more attention has been paid to the combined heating and power microgrid(CHP-MG),however,there are two challenges in its scheduling:first,the CHP-MG solves the electrical and thermal load requirements through the CHP unit,however,there is a rigid coupling relationship between electricity and heat of CHP units,which limits the flexibility of power and heat dispatching;second,the permeability of renewable energy in CHP-MG is high,so it is difficult to solve the uncertainty of load and renewable energy.In view of the above problems,under the grid-connected operation mode of CHP-MG?this paper proposes an optimal scheduling strategy based on energy storage real-time corrected double-loop control.The coordination operation of storage system and CHP unit is adopted.The outer-loop is targeted at the lowest operating cost,while optimizing the power supply cost and heating cost.This not only eliminates the electro-thermal coupling,but also flexibly carries out the joint optimal dispatch of electro-thermal.The inner-loop is based on the real-time energy storage correction algorithm,which does not depend on the accuracy of the prediction data.It can adjust charge/discharge heating or power flexibly and has the ability to cope with the impact load.Under the island operation mode of the CHP-MG,the demand for solving the uncertainty of load and new energy output is higher,and the power fluctuation needs to be balanced in real time.An optimal dispatching method of multi-time-scale coordinated double-loop control for isolated microgrid is proposed.The combined optimal dispatching of heating and power is carried out flexibly through double-loop control,and the reliability of power supply is guaranteed by multi-time-scale coordination.In the pre-scheduling stage,a certain margin of peak-shaving capacity is set for real-time operation to cope with power fluctuation.In the real-time scheduling stage,the pre-scheduling stage can be fed back by actual output,the reserve factor of peak-shaving power can be corrected,and the pre-scheduling plan can be updated.The islanding dispatching mode can consider the reliability of power supply from the overall point of view,and can adjust the dispatching plan flexibly and effectively.