Spot market clearing method and system considering back-to-back direct current modeling

The invention provides a spot market clearing method and system considering back-to-back direct current modeling. The method comprises the following steps: obtaining spot market clearing basic data and back-to-back direct current data; constructing a security constraint unit commitment model based on spot market clearing basic data; based on the back-to-back direct current data, increasing constraints for the safety constraint unit combination model to obtain a spot market clearing model so as to regulate and control the section power flow; and solving the spot market clearing model, obtaining a solving result, and realizing spot market clearing based on the solving result. According to the spot market clearing method considering back-to-back direct current modeling, the section power flow is regulated and controlled through back-to-back direct current modeling, overload of the section power flow can be effectively relieved, rationality and reliability of a unit combination and a power plan are guaranteed, an