Multi-rate Parallel Transient Simulation of Active Distribution Network Based on Optimization Decomposition Strategy

With increasing species of elements and penetration of distributed generation, the dynamic process of network becomes more diversified, bringing a lot of difficulties for parallel transient simulation of distribution network. Aiming at the problem that the transient simulation method of active distribution network does not consider the influence of dynamic characteristics of elements on computational complexity and the requirement of simulation step size, this paper puts forward a multi-rate parallel simulation method with adaptive variable step sizes based on optimal decomposition strategy. Considering the difference of transient response speeds and computational complexity among different elements, an optimal decomposition strategy of active distribution network is proposed with the goal of balancing the computational complexity of each core and minimizing interactive data between cores. On this basis, an equivalent model of interfaces and a coordination model of subnets are established, and a parallel simulation method of multiple rates and variable step sizes is proposed to accelerate the transient simulation. The case study of 12 feeders at the same bus in a substation verifies that the proposed parallel simulation method can meet the transient simulation requirements of the distribution network and greatly improve computing speed while ensuring simulation accuracy. © 2020, Power System Technology Press. All right reserved.