In the cross-regional grids electricity transaction

deviation electric quantity and its reasonable pricing is an important problem demanding prompt resolution

which is directly related to the economic interests and fairness of the parties to the transaction. A novel method is proposed to determine the responsibility and pricing for the deviation electric quantity of cross-regional AC grids based on frequency average deviation. The power exchange center can get the relevant data through power network dispatching and gateway electricity meter every trading day to obtain inter-regional exchanging electricity quantity in each time interval. The deviation electric quantity along with the frequency average deviation in that time interval are calculated. The “米” shaped diagram of tie line deviation electric quantity can be drawn via frequency and electric quantity deviation in each time interval of the trading day. The responsibility party and the corresponding responsible level of deviation electric quantity are determined according to the operating point of each time period in the different eight areas of the “米” diagram. Then the different penalty prices of deviation electric quantity are set on the basis of the deviation responsible party and its level

settling accounts monthly by clearing daily. Thus the pricing differences and separate settlement between the cross-regional grids trading contract electric quantity and deviation electric quantity are realized. Simulation results show the feasibility and effectiveness of the method. This work is supported by State Grid Corporation of China(No. JS033〔2014〕).