Electromagnetic Transient Simulation Of DC Distribution Power System

Along with the increasingly urgent demand for energy and severe environmental problems, wind generation, photovoltaic power generation and other renewable energy technologies as well as energy storage technology attract more and more attention. Compared with AC (Alternating Current, AC) power distribution system, the DC (Direct Current, DC) power distribution system has more advantages in renewable generation accommodation. To study the running characteristics and dynamic response of DC power distribution system, system simulation of DC power distribution system is inevitable. The DC power distribution system consists of electric network and control network. Because of the numerous power electronic devices and the complex control logic of power switches, simulation of the control network becomes difficult. This thesis sections as following:Firstly, the simulation of DC power distribution network was studied systematically, and models of photovoltaic batteries, lithium batteries, VSC converter and other components of the simulation were built respectively. Models of basic components were built, including electric components and control components. Cases of models were used to demonstrate the accuracy of the modeling.Secondly, in order to improve the efficiency of the simulation, the paper proposed a parallel algorithm of the control system simulation. Because of the numerous power electronic devices and the complex control logic of power switches, simulation of the control network becomes difficult. Time delay components are prevalent among all components, by which the control system were divided into decoupling parts. By using the parallel algorithm, the DC electromagnetic transient simulation program was optimized. Through the method of time delayed decoupling, the control network of the simulation system was partitioned. Thus, the overall simulation speed and degree of parallelism were improved effectively.Finally, a simulation platform was developed. To improve the efficiency of the algorithm, MATE algorithm and time delay parallel algorithm were used. Finally, a sample example is employed to demonstrate the feasibility and validity of the model built and algorithm developed.