Dispatching Control Strategy And Application Analysis Of DC Distribution Network

With more and more new energy and new loads being connected to the distribution network,the traditional AC distribution mode can not meet the requirements of the development of the power grid in the new era.Compared with the traditional AC distribution network,the DC distribution network,through adopting DC transmission which reduces the step of commutation link,is more convenient for the access of distributed power generation,energy storage unit as well as DC load.At the same time,DC distribution network has more advantages,such as,the better power quality,larger power supply capacity,less power loss and higher power supply reliability.These advantages make DC distribution network become a new direction of distribution network development in the future.With the increasingly deep research,DC distribution net work will have a broad prospect.Firstly,this Paper analyses the common topological structures of medium-Voltage DC distribution network and low-voltage DC distribution network and introduces the bus structure of DC distribution network.Through studying the influencing factors of voltage level in DC distribution network,the classification of DC voltage level is given.This paper analyzes the main equipments in DC distribution network,such as AC/DC converter,DC circuit breaker,energy storage equipment,etc.Then,the dispatching control strategy of DC distribution network is studied.The working principle of energy management system and the shortcomings of traditional scheduling strategy are analyzed.AS DC distribution network is a typical dynamic network,it is necessary to satisfy the requirements of non-linearity,multi-constraints and dynamization,in order to optimize the dispatching of DC distribution network,so a multi-period real-time dispatching strategy is adopted.The objective function is established to optimize the total operating cost of the system.Constraints are set on the premise of guaranteeing internal power balance and safe and reliable operation of each part of the power grid.Thus,a mathematical model of optimal scheduling is established,and it is verified by an example.Finally,the power supply capability and economy of AC and DC distribution network are analyzed and studied.The advantages of DC distribution network are proved by calculation and comparison.However,it does not mean that the DC distribution network is the best choice in all situations.It is necessary to make an appropriate choice according to the actual situation and specific analysis of specific problems.