电力系统微分代数模型的奇异性和暂态电压稳定

将电力系统微分代数模型的奇异性与暂态电压稳定相联系，用动态负荷模型逼近静态负荷模型，以消除原微分代数方程模型中的奇异性。在2机单负荷3节点系统和新英格兰39节点系统中构造算例，证实了系统在原奇异点附近具有暂态电压崩溃的特征，从而微分代数方程的奇异性可以作为暂态电压崩溃的一种机理解释。此外，还研究了动态负荷模型时间常数、负荷功率和负荷成分对暂态电压稳定性的影响。研究结果表明具有恒功率或恒电流负荷特性且负荷响应较快的系统在重载下易发生电压崩溃。上述结论对研究暂态电压稳定的机理、电压稳定和功角稳定的关系、电力系统微分代数方程模型的理论和仿真分析具有一定的参考价值。

Relationship Between Transient Voltage Stability and Singularity in Power System Differential-algebraic Model

The singularity in power system differential-algebraic model is related to transient voltage stability in the paper. By using a type of dynamic load model instead of static load model, the singularity in DAE is eliminated. Case studies in two-generator single-load three-bus system and New England 39-bus system proved that the system state near singular point has the characteristic of transient voltage collapse. Hence, the singularity of the differential-algebraic model can act as a kind of mechanisms for transient voltage collapse. The influences of time constant in dynamic load model, load power and load constitution on transient voltage stability are also studied. The results indicate that the power system with the load having the constant power and constant current load characteristics and quick response ability is prone to voltage collapse under the heavy load conditions. The above conclusions are helpful for the studies of transient voltage collapse mechanism, relationship between voltage stability and angle stability, theory and simulation methods for power system differential-algebraic model.