Research On Energy Storagy Modeling And Control Strategy Of The Air Conditioning Load

Air-conditioning load is the most significant part of the power peak load, bringing great negative impact on the economic and safe operation of power grid. On the other hand, Air-conditioning system has thermal storage ability, which has the huge potential of load regulation, and is becoming the important demand response resources under smart grid, with the fast speed and great potential in demand response. However, approaches to air conditioning load control technology to keep the balance of power and improve system operation efficiency are not fully provided. Therefore, it is of great significance to do the research on how to connect the demand side resources of air-conditioning load effectively into dispatch operation of power system through load scheduling.Based on the energy storage characteristic of the air-conditioning system analyzed in this paper, the air-conditioning system’s energy storage model is established. On this basis, the models of aggregation technology for air-conditioning load are fully studied, and the control strategy of air-conditioning demand response resources’ participation in economic dispatching and secondary frequency regulation of power system is proposed.Firstly, feasibility and necessity of mining demand response potential of air conditioning load participating in power system dispatching is analyzed and present development and application of air conditioning load control at home and abroad is outlined. Besides, the current academic research is summarized from three aspects, including load model, aggregation technology and operational control, laid the foundation for the follow-up research.Secondly, energy storage characteristic of the air conditioning system are studied, considering the building thermal storage characteristics and human thermal comfort requirements. Compared with the existing typical energy storage component, the energy storage model for air-conditioning system is put forward, which has a larger application advantage, compared with the tranditional equivalent thermal parameters model in two aspects of saving storage space and compatibility.Then, the control architecture of the air conditioning load participating in secondary frequency regulation of power system is presented, focusing on the establishment of the air conditioning load aggregation model and the control strategy for energy storage componets. In load aggregation model, the cluster load of air conditioning will be integrated into a virtual AGC generator unit, with the representation of its regulation capacity, regulation speed and regulation precision, which enables it participating in the system frequency regulation like traditional units. The AGC instructions will be inversed into open or stop control signal of air-conditioning equipment through the control strategy.Finally, transfer matrix reflecting changes of SOC state probability density of the cluster load of air-conditioning is deduced using the principle of Markov chain, based on the storage model. And aggregation model of the air conditioning load is established to obtain output range of virtual generator units integrated with the cluster load of air conditioning, under temperature set point adjustment scenarios. Based on the traditional scheduling model, a new economic dispatch mathematical model containing air conditioning load control, which focus on the air conditioning load adjustable ability and the adjustment cost, is put forward.