Research On Key Technologies Of Optimized Scheduling Of Large Scale Air Conditioning Loads

In recent years,with the development of economy and the increasing power load,air-conditioning has been widely used,the peak-valley gap of power grid has been further widened,and the contradiction between supply and demand has become increasingly prominent.Summer is the peak of electricity use,but also the peak of air-conditioning use.In order to ensure the safe operation of the power grid,it is necessary to regulate the air-conditioning reasonably to participate in the demand response of the power grid.Therefore,this paper takes the large-scale decentralized air-conditioning as the research object,combines the model,control means and response characteristics of air-conditioning,respectively from three levels of operators,load aggregators and air-conditioning users,and proposes a set of multi-level optimal dispatching strategies for large-scale air-conditioning to participate in demand response.The main research work of this paper is as follows:1)The modeling mode,control means and response characteristics of large-scale air-conditioning are studied.Equivalent thermal parameter model is established,switching control and temperature control are put forward to keep diversity,and supported by clustering method of large-scale air-conditioning to keep diversity,so that each group contains the same number of all-state air-conditioning,avoiding power fluctuation caused by air-conditioning scheduling.The adjustable potential of air-conditioning in groups is calculated.The response characteristics of air-conditioning are analyzed,and based on the analysis of the randomness of response,the correlation of response also needs to be considered.2)An aggregator declaration model considering the response characteristics of air-conditioning is proposed.An improved Latin hypercube sampling method is proposed to model the response characteristics.Emphasis is laid on the analysis of the scene where the correlation coefficient matrix is not positive definite due to the increase of the number of air-conditioning users.The hypersphere decomposition method,spectral decomposition method and the improved alternating projection method are used to correct the scene in turn.Considering the response characteristics of air-conditioning,the cost and benefit of load aggregator are analyzed.A decision-making model considering air-conditioning and energy storage is established and solved by stochastic simulation and genetic algorithm.The example analysis proves that adding energy storage can get higher profit than not adding energy storage.It also verifies that air-conditioning users with different correlations have different benefits.At the same time,it verifies that the mean value of responsiveness distribution parameters is positively correlated with profit,and the standard deviation is negatively correlated with profit.The research results have certain guiding significance for the reasonable selection of adjustable load for the aggregator.3)A multi-level optimal dispatching model for large-scale air-conditioning participating in demand response is proposed.The optimal dispatching models of upper operators,middle load aggregators and lower air-conditioning users are analyzed in detail.The optimal dispatching model for upper operators with the lowest dispatching cost and network loss,the optimal decision-making scheme for middle-level aggregators with the highest profit and the response characteristics,and the optimal control method for lower air-conditioning users with the least number of shutdowns and dispatching deviation are proposed respectively.The improved Latin hypercube sampling method,genetic algorithm,optimal power flow algorithm and other algorithms are used to solve the problem.An example shows that the optimal dispatching strategy proposed by operators can effectively prevent voltage overshoot,optimize the operation of power grid,reduce the cost of network loss and the payment cost of load aggregator;the middle-level aggregator optimal decision-making scheme with maximum profit and response characteristics can effectively improve the profit of load aggregator,and the number of shutdowns is the least considered adjustment.The optimal control method of degree deviation can control the error within 1%,and effectively reduce the number of shutdown of air-conditioning.