Transmission Expansion Planning in the Electricity Market Environment with Considering Price Signals

With the further deregulation of the electricity market, the number of market participants are expanding; the elements of the system are increasing; and the complexity of the network is growing. The traditional transmission expansion planning only considers the optimization of line investment costs, which can no longer meet the needs of the market environment with volatile price signals that have long-term trend impact on the investment plans. Therefore, based on the analysis of the price formation mechanism in the market, this paper proposes a set of congestion indice that can reflect the driving changes of price signals in the market environment. By using the congestion index, the traditional transmission expansion planning model can be improved, and the transmission expansion planning model considering the price signal in the market environment is proposed. The Garver 6-node system is used for example verification, and the results out of traditional transmission expansion planning are compared with the results of the model proposed in this paper. The results of the calculation examples show that the model proposed in this paper can better adapt to the needs of the electricity market environment. It can be concluded that when planning in the market environment, it is necessary to take into account the impact of power system congestion costs and line investment costs at the same time.