基于Parareal算法的VSC-HVDC电磁暂态计算方法

针对VSC-HVDC系统,考虑Parareal并行计算方法的并行性与高效性特点,提出一种电磁暂态计算问题方法,以提高VSC-HVDC系统电磁暂态计算速度与数值精度。首先,建立VSC-HVDC时域动态模型,并使用Parareal方法进行计算,该方法通过划分整个仿真时间为一系列子区间,将各子区间内的初始值用一组满足网络初始条件的近似解来表示;其次,利用这组初始值在各子区间内单独、同时进行计算求解;最后,通过预估-校正的方法得到精细解。算例测试表明:该算法可获得有效的加速比及较高的并行效率,应用于VSC-HVDC系统电磁暂态数值仿真中能显著提高计算速度。

Electromagnetic transient calculation method of VSC-HVDC based on Parareal algorithms

In order to improve calculation speed for the electromagnetic transient of VSC-HVDC system without lossing accuracy,the Parareal method is applied to the electromagnetic transient simulation of VSC-HVDC.At the beginning,the VSC-HVDC time domain dynamic model is established.Then the model is calculated by employing the Parareal method.This method can decomposed the whole simulation time into a series of subintervals and a coarse approximation of the trajectory is utilized to supply the initial conditions at each subinterval.Secondly,using this set of initial values solves the evolution problems at each subinterval concurrently and separately.Then a fine solution is obtained by using an estimate-correction method.The experimental results show that the algorithm can obtain a more effective speed ratio with a high parallel efficiency.It can improve the calculation speed of VSC-HVDC system in electromagnetic transient numerical simulations.