A Control Strategy of Air-Conditioning Load Groups and Optimization Scheduling as Demand-side Resources Participating in Grid

At present, the air-conditioning load participates in the demand side management of power grid, and the operation characteristics of the load are in accordance with the fixed frequency. Considering that under the same temperature interval, the number of status of the fixed frequency air-conditioning varies in different temperature ranges, in this paper the air-conditioning load was divided into two types, namely fixed frequency air-conditioning and variable frequency air-conditioning. And an optimal scheduling strategy for air conditioning load groups to participate in power grid regulation was proposed. To effectively solve load fluctuations caused by changes in the number of operating condition during the temperature regulation, a strategy combining the temperature control and direct on/off control was used for the fixed frequency air-conditioning. In response to the user-side demands, the steady-state and dynamic load models were established for the variable frequency air-conditioning based on their operating characteristics. Based on the load model of fixed frequency air-conditioning and variable frequency air-conditioning, discrete particle swarm optimization algorithm was used to simulate and optimize the scheduling model. Given the air-conditioning load that participated in the demand response was fixed, five kinds of control strategies were simulated in two cases of the different regulation durations under the same reduction amount, and the different reduction amounts under the same regulation duration. The results showed that under the same reduction amount or the same regulation duration, the increasingly elevated regulation duration or reduction amount would lead to the decreased flexibility of the temperature regulation mode in each aggregate group. However, the ratios of the standard deviation of the regulation to the reduction amount were less than 3% in general, and the maximum power saving of air conditioning load group can be calculated under the same reduction amount or duration. Therefore, within a certain regulation range, the air-conditioning load as the demand side resource can fit the control target effectively. In addition, the load aggregators can achieve the reasonable load reduction amounts and reduction durations based on the regulation of the air-conditioners so as to improve the peak valley characteristics of the grid load. © 2017, Editorial Department of Advanced Engineering Sciences. All right reserved.