Operation Mechanism And Scheduling Strategy Of Electric Vehicles For Participation In Frequency Control Ancillary Services

The current energy structure of the world is in the process of huge evolution,many countries are committed to the use of clean energy to replace traditional fossil energy,so as to reduce carbon emissions.Clean energy like wind power,photovoltaic and other renewable energy’s application scale is constantly expanding.This makes the increasingly complex power system face both challenges and opportunities in maintaining frequency stability:on the one hand,the increasing scale of renewable energy access brings more uncertainty to the frequency stability of the power system on the power side;on the other hand,with the continuous progress of demand-side response technology,the idea of providing frequency regulation reserve capacity by flexible loads to absorb short-term frequency fluctuations is also gaining more and more attention.Demand-side resources,such as electric vehicles and central air conditioners,which can perform power regulation in a short period of time,have the advantages of low deployment cost and fast response time when participating in frequency regulation services.However,most of the research on the participation of demand-side resources in frequency regulation is still at the theoretical stage,and the main difficulty of its application is that the participating demand-side resources will face the demands of both power consumption and system frequency regulation demand,as well as the uncertainty of the load’s own power consumption and the interference with the load’s power consumption after participating in frequency regulation.In addition,power system of many countries are exploring compensation mechanisms for frequency regulation service participants,but the compensation mechanism for each individual will also affect their willingness to participate after different individuals on the demand side are aggregated as an aggregator,but there is no mature research on the compensation mechanism for each load within the aggregator in this regard.Based on the above background,in order to realize demand-side load aggregators’participation in frequency regulation services,this paper establishes an operational model of frequency reserve optimization,real-time power scheduling,and compensation settlement mechanism with aggregators as the research objects,and the specific research contents include the following aspects.1)The uncertainty scenario description problem is studied.For the optimal scheduling problem of reserve capacity when aggregator participation in frequency regulation services,the uncertainty on both sides of system regulation demand and load electricity consumption is addressed.On the system side,the conversion method from regulation signal sequence to energy storage demand is proposed based on historical signal data,thus giving the uncertainty description method of regulation demand;on the user side,the time-series correlation of electricity consumption data is studied and a data-driven electricity load prediction method is proposed.2)The aggregator’s power consumption/reserve capacity optimization problem is studied.Based on the uncertainty scenario description,the adjustable capacity evaluation method of demand-side resources participating in frequency regulation is studied and used as the boundary condition for optimal dispatching,as well as the evaluation method of real-time regulation response under this boundary condition,the cost/revenue expectation of aggregators is evaluated before real-time response,the risk of aggregators failing to meet customers’ power consumption/frequency regulation demand under the power constraint is focused on,and the risk cost is quantified and added to the optimization The cost/benefit expectation of aggregators is evaluated before the real-time response,focusing on the risk of aggregators not being able to meet customers’ electricity/frequency regulation demand under power constraints,quantifying the risk cost and adding it to the optimization target,maximizing the overall revenue of aggregators,and fully exploiting the adjustable margin of demand-side resources for grid frequency recovery.3)The power allocation scheduling problem of aggregators responding to theregulation demand in real time is studied.For loads with different physical characteristics and sizes,as well as their respective power demand,a common adjustable margin evaluation method is studied,and the margin parameter is used as the core index for scheduling,so that the total power consumption of the aggregator,consisting of power consumption plan and regulation demand,is allocated to each load in the real-time phase to meet the goals of both power consumption and regulation demand.Through this method,different loads are aggregated and dispatched together to support each other,improve the overall frequency regulation effect and power consumption satisfaction,and ultimately enhance the economic efficiency of the aggregator and each load.4)On the basis of the above EV aggregator’s frequency regulation service participation model,air conditioning loads are introduced to study the collaborative scheduling problem of both loads.For loads with different physical characteristics and different power scales,as well as the respective power demand of these loads,a general regulable margin evaluation method is studied,and the margin parameter is used as the core index of dispatching to allocate the total power consumption of the aggregator,which is composed of power consumption plan and frequency regulation demand,to each load in the real-time stage,so as to meet the objectives of both power consumption and frequency regulation demand.The aggregation of different loads and cooperative dispatching achieve mutual support,improve the overall frequency regulation effect and power consumption satisfaction,and ultimately enhance the economic efficiency of the aggregator and each load.