Study On The Strategy Of Coping With High Proportion Of Renewable Energy Power Generation

With the large-scale renewable energy generation access to the grid such as wind and PV,and the deepening of the concept of clean energy utilization,the power system is experiencing the process of transition from passive renewable energy such as fossil fuels,actively adjustable to the controllable energy generation.In the process of power generation conversion,a high proportion of renewable energy power generation has become the trend of the grid.In response to this trend,the active load of distributed energy storage and electric vehicles has also been rapidly developed.In this context,the limited thermal power unit's regulation can't effectively accommodate high-ratio renewable energy generation,the problem of how to connect and coordinate artificially introduced flexible resources such as energy storage and how to allocate them more effectively need to be clarified.This paper takes the capacity of renewable energy as a clue,mainly discusses the strategies to solve these problems,and expects to provide guidance and Suggestions for long-term power system planning.The main work and results are as follows:Firstly,after the power supply structure changed,the reduction of the thermal power unit makes the probability that the adjustable capacity is insufficient or the adjustment speed is difficult to meet the fluctuation of the renewable energy in the unit combination stage.The frequency regulation effect is not negligible as the basis of the system to deal with the uncertainty.The power balance in the simulation operation is added to the slack amount,and based on this,the active deficiency and standby vacancy evaluation indicators are established,and the time series production simulation model considering the frequency regulation effect is established to evaluate the ability of the thermal power unit to absorb the renewable energy generation.The relationship between generating capacity,power structure and regulating parameters of thermal power units is discussed.Secondly,the energy storage in the large power grid participates in the collaborative planning of various types of power sources.The energy storage system participates in the long-term planning of the power supply,replacing some thermal power units with only regulating functions,reducing the investment cost of the thermal power unit,and its value is more fully reflected in the long-term planning.Establish a collaborative planning model for active power(thermal power,etc.),passive power(renewable power such as wind and light),and indirect active power(storage system),with the goal of minimum cycle cost,including investment decision module and production simulation module,which iterate with each other to get the final planning result.Analyze the value of energy storage system in long-term planning.Finally,the distributed energy storage configuration problem in the active distribution network.Considering that renewable energy exists in a distributed form in the distribution network in the future,resulting in the generation of bidirectional currents.Voltage quality becomes an important factor restricting the consumption of renewable energy,and the energy storage system can not only suppress the reverse current by adjusting the active power,but also,the voltage quality can be improved by adjusting the reactive power,thereby promoting the outward transfer of the active power of the renewable energy and improving the system's ability to absorb.This paper defines three states in which voltage quality affects the generation of renewable energy,and establishes the siting capacity determination and operation strategy optimization model of distributed energy storage that takes the voltage quality into account,and analyzes the role of distributed energy storage in assisting the absorption of renewable energy power generation.