Evaluation method for transmission capacity and constraints of multi-channel AC/DC hybrid section

Abstract

The invention discloses an evaluation method for the power transmission capacity of a multi-channel AC / DC hybrid cross-section and its constraint conditions. Firstly, the AC-DC power flow transfer ratio matrix D of the hybrid cross-section and the load rate matrix η of the AC line are calculated, and then according to the matrix D Calculate the line load rate matrix λ after the N-1 fault occurs on the AC line with the matrix η and the rated power of each AC line; judge whether the maximum element in the line load rate matrix λ is 1, and adjust the power flow of the AC section according to the judgment result, and then Calculate the power transmission capacity P of the AC section a ; Then calculate the transmission capacity P of the flexible DC section d ;Finally, according to the transmission capacity P of the AC section a and the power transmission capacity P of the flexible DC section d Determine the power transmission capacity and constraints of the hybrid section. The invention can realize the rapid evaluation of the power transmission capacity and constraint conditions of the multi-channel AC-DC hybrid cross-section with flexible direct current, has short calculation time, high calculation efficiency and relatively accurate and reasonable calculation results.

Description

technical field [0001] The invention relates to the technical field of power system analysis, in particular to an evaluation method for the power transmission capacity of a multi-channel AC-DC hybrid cross-section with flexible DC and its constraint conditions. Background technique [0002] At present, the power system has gradually formed a national interconnection pattern with a clear transmission and reception relationship. As an important connection line group connecting the power grid regions, the transmission section is the key monitoring and control object for the safe operation of the system. With the rapid development of DC and flexible DC transmission technologies, the composition of the transmission section has changed from the traditional AC section to the AC-DC hybrid section, and the operating characteristics of the section are more complex. In a traditional AC section, after a certain line fails to operate, the power of the line is transferred to other AC line...

AI Technical Summary

Problems solved by technology

[0004] Compared with the calculation of the transmission capacity and constraint conditions of the traditional AC section, the calculation of the transmission capacity and constraint conditions of the multi-channel AC-DC hybrid section with flexible DC is more complicated

In the calculation process, it is also necessary to pay attention to the selection of the flexible DC rated capacity. At present, after the initial determination of the flexible DC rated capacity, the flexible DC rated capacity is corrected through a large number of AC-DC hybrid cross-section power transmission capabilities and constraint conditions. This method The relationship between the flexible DC rated capacity and the transmission capacity of the AC / DC hybrid section cannot be fully explored, the selection of the flexible DC rated capacity is not reasonable enough, and the traditional calculation method of the section transmission limit is to determine the limit value through a large number of power flow calculations and stability calculations. This method has the problems of complex calculation, large amount of calculation, and long time consumption, and cannot quickly and accurately evaluate the transmission capacity and constraints of multi-channel AC-DC hybrid sections with flexible DC

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