Mixed Linear Model of a Safety Dispatch Model in an Active Distribution Network for Source–Grid–Load Interactions

Abstract

There are a large number of plug-and-play loads in an active distribution network, such as EVs(Electric Vehicles), energy storage, solar power, etc. Due to the lack of security control methods for each terminal node and the lack of distributed power voltage control methods, the large number of loads brings a huge challenge to the security of the distribution network. At present, some regional distribution networks dominated by new energy in China have long-standing problems, such as high voltage impact and frequency flickering, which are extremely harmful to electric equipment, and the resulting load-side accidents have brought huge economic losses. Therefore, research on an optimization model of the source–grid–load interaction in the active distribution network considering the safety characteristics, especially the voltage of the system, will help to improve the quality of the grid dispatch. In this paper, the safety limits of the independent operation of a source network loaded on three sides are used as the operating constraints of the system, and the social welfare of the interaction is maximized as the goal. A joint optimization modeling after the independent solution of the three sides is used as the core means, a heuristic algorithm is used to solve the overall optimization of the whole system, a scheduling optimization model that meets the system security goals is constructed, and this model is used to guide the operation strategy of each node in the system. The Lagrangian relaxation factor is introduced for structural optimization, and finally, the simplified 36-node model of the actual power grid is used for verification. The results show that under the goal of ensuring the economy of the system, the system voltage is controlled within the specified range of the safe operation of the system, which can meet the safety needs of the interaction.