基于稳定域边界二阶逼近的暂态电压稳定分析

电力系统中暂态电压失稳事故时有发生从而引起电力界广泛关注。目前的暂态电压稳定分析方法尚存在不足之处。本文基于非线性动力学的半张量积方法研究电力系统暂态电压稳定问题,以期在电力系统发生大扰动后快速判断故障后系统的电压稳定性,从而有利于及时采取控制措施避免系统崩溃。论文首先建立了暂态电压稳定分析的系统综合模型,主要包括对暂态电压失稳至关重要的发电机、励磁、感应电动机和输电网四个子系统。在此基础上,提出了基于稳定域边界二阶逼近的暂态电压稳定判据;在一个简单系统进行的实例分析表明所提出的暂态电压失稳判据具有速度快、准确度高及易于计算机实现的特点,具有较高的工程实用性,可望有效判断故障后系统的暂态电压稳定性。

Transient Voltage Stability Analysis Based on Second-order Approximation of Stability Boundary

Since accidents due to transient voltage instability happen occasionally in power systems, enhancement of transient voltage stability has become significant and has been getting more and more attention within power system field.However, the existing methods of analysing transient voltage stability have some shortcomings.This paper tackles the problem of transient voltage stability by using the semi-tensor product method of non-linear dynamics.The aim is to estimate voltage stability of post-fault power systems rapidly, so that a proper control method can be adopted in time to prevent power systems from collapse.Firstly, a general power system model for transient voltage stability analysis is established.This mode takes into account generators, excitations, motors and transmission systems.Secondly, based on the second-order approximation of stability boundary, a criterion is proposed to estimate transient voltage stability. Finally, simulation results performed on a simple system show that the proposed criterion has some advantages, such as rapid convergence, high accuracy and high practicability, and can be used for effective estimation of transient voltage stability of post-fault systems.