Optimal dispatch method for virtual capacity expansion of distribution transformer station area considering economic cost

With the accelerated construction of new power system, the phenomenon of heavy overloading occurs in some distribution transformer station areas, which seriously affects the reliability of power supply. The traditional method of expanding the capacity of transformers is high in cost and poor in flexibility. This paper proposes the concept of virtual capacity expansion, establishes a virtual capacity expansion optimal dispatch model that considers the cost and benefits of combine energy storage and flexible resources such as electric vehicles and inverter air conditioners, and comparatively analyzes the applicability of actual capacity expansion and virtual capacity expansion in different situations from the perspective of economy. The example shows that virtual capacity expansion can effectively increase the remaining capacity of the distribution transformer station area and alleviate the problem of heavy overload without expansion of power distribution facilities, while its implementation cost decreases with the increase of the price difference between different kind of time periods in time-of-use price.