基于全电磁暂态数学模型的大规模交直流混联电力系统暂态稳定性仿真方法研究

Historically, due to the restrictions of computational tools and computing technology, the mechanical movement of the generator rotor transient process is ignored in electromagnetic transient process simulation, and the electromagnetic transient process of the generator stator winding is ignored in electromechanical transient process simulation. Obviously, these two kinds of transient process has influence on each other. In modern power systems, HV- and UHV-DC transmission lines are numerous, the power electronic equipments inside the converter stations are very sensitive to electromagnetic transient process. Usually, the transmission power of DC transmission lines are bigger, its operation status has important influence on system stability. Under these conditions, a natural question is: will it have disruptive influence on the results of system stability analysis, when ignoring or not to ignore the electromagnetic transient process of transmission network (including the converter station)? This proposal is aiming at studying a system electromagnetic transient and electromechanical transient unified simulation scheme, by abandoning the network quasi-steady-state model, and taking generator stator winding electromagnetic transient process into consideration. We will establish the full electromagnetic transient mathematical models of the system electromagnetic transient and electromechanical transient unified simulation; Then seek a numerical integration method that can satisfy the simulation precision and numerical stability requirements of rigid systems; And improve the simulation speed using suitable parallel computing framework. This research has both theoretical significance and engineering application values. Up to present, no similar results has been reported in the world.

由于计算工具和计算技术的制约，历史上电磁暂态过程仿真忽略发电机转子的机械运动暂态过程而机电暂态过程仿真忽略发电机定子绕组的电磁暂态过程。显然，这两种暂态过程是相互影响的。现代电力系统中已含有众多的高压、特高压直流输电线路，构成换流站的电力电子设备对系统的电磁暂态过程十分敏感。通常直流输电线路的输送功率较大，其运行状态对系统的稳定性有重要影响。在这种条件下，一个自然的问题是：忽略与不忽略输电网络（含换流站）的电磁暂态过程，对系统稳定性分析的结果是否有颠覆性影响？本课题旨在研究抛弃网络准稳态模型、计及发电机定子绕组电磁暂态过程的全系统电磁暂态与机电暂态统一仿真方案。研究将建立系统电磁暂态与机电暂态统一仿真的全电磁暂态数学模型；寻求满足刚性系统仿真精度和数值稳定性要求的数值积分方法；并采用合适的并行计算框架来提高仿真计算速度。研究具有理论意义和工程应用价值。目前国内外未见有同类研究的成果报导。

由于计算工具和计算技术的制约，历史上电磁暂态过程仿真忽略发电机转子的机械运动暂态过程而机电暂态过程仿真忽略发电机定子绕组的电磁暂态过程。显然，这两种暂态过程是相互耦合的。现代电力系统中已含有众多的高压、特高压直流输电线路，构成换流站的电力电子设备对系统的电磁暂态过程十分敏感。通常直流输电线路的输送功率较大，其运行状态对系统的稳定性有重要影响。因此，有必要研究抛弃网络准稳态模型、计及发电机定子绕组电磁暂态过程的全系统电磁暂态与机电暂态统一仿真方案。目前国内外尚未见有同类研究的成果报导。.本项目针对交直流混联系统电磁暂态与机电暂态统一仿真的全电磁暂态数学建模问题，采用电磁暂态仿真中的等效电导与历史电流源并联模型框架，建立了输电线路、HVDC及其控制系统、变压器和同步发电机的全电磁暂态时域仿真模型，来进行交直流混联系统暂态过程的统一仿真。.在全系统所有元件采用详细电磁暂态模型之后，系统统一仿真问题的计算规模巨大，系统各元件的微分方程加上网络的代数方程众多，使得整个方程组的维数很高、刚性问题突出。通过对各种线性多步法LMM的数值稳定性、收敛性等方面的分析和对比，提出了一种能够有效抑制数值振荡的2级隐式龙格库塔DIRK法，提高了系统统一仿真计算的数值稳定性、精确性和求解速度。.针对大规模元件的全电磁暂态模型下的数值计算效率问题，提出了一种新型的基于CPU+GPU电力系统全电磁暂态仿真异构并行仿真方法。通过对每步数值积分中的全电磁暂态元件历史电流源更新的密集矩阵计算特点分析，该并行仿真方法，能够大幅提高采用全电磁暂态模型的暂态统一仿真的求解效率。本项目的研究具有一定的理论意义和工程应用价值。.