Method for calculating maximum power supply capability of active power distribution network based on second-order cone relaxation

Abstract

The invention relates to a method for calculating a maximum power supply capability of an active power distribution network based on second-order cone relaxation, belonging to the field of power system optimized evaluation. The method related by the invention comprises the steps of: considering all scenes of different main transformer faults and introducing new parameters for expressing different fault scenes; establishing a maximum power supply capability calculation model of the active power distribution network based on the second-order cone relaxation, wherein an objective function of the model is to maximize a total load capacity in the active power distribution network subtracting a weighted network power loss and simultaneously needs to satisfy each technical constraint for power network operation; and setting a second-order cone constraint for describing a load flow variable relationship in the active power distribution network. By solving the model, an evaluation result on the maximum power supply capability of the active power distribution network can be obtained, namely, a total load upper limit under the condition that distribution transformer N-1 constraints are met, and a load value of each node correspondingly when the load upper limit is used. The evaluation model established with the method of the invention is very precise, suitable for practical situation and easy to solve, and has very strong practicability.

Description

technical field [0001] The invention relates to a method for calculating the maximum power supply capacity of an active distribution network based on second-order cone relaxation, and belongs to the field of power system optimization evaluation. Background technique [0002] The fault of the main transformer (referred to as the main transformer) of the active distribution network is the most serious fault. A safe distribution network requires that all power-off loads can be transferred when the main transformer fails. When any transformer in the substation fails, if the load under it has the ability to be transferred by other transformers in the same station, or through the connection line between feeders, it is said that the distribution network system meets the distribution transformer N-1 safety constraints . When the active distribution network system satisfies the N-1 constraint of the distribution transformer, the total load will have an upper limit, that is, the maxi...

AI Technical Summary

Problems solved by technology

Therefore, the traditional model (1-1) only considers the constraints of the connection capacity between feeders, the constraints of the main transformer, and the condition that the power-off load can be transferred after any main transformer failure, so as to maximize the load carrying capacity of the distribution network. , does not involve the specific constraints of branch flow and node voltage, and does not consider the reconfigurability in the feeder, which will make the power supply capacity assessment results too optimistic or pessimistic and deviate from the actual situation

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