Study On The Influence Of Power System Component Parameters On Transient Stability

With the power continuous developed and its scale expanded and factors affecting the transient stability of power grid increasing, the grid stability failure has more and more big damage to power system and the social economy. Therefore, an accurate grasp of the actual grid operating characteristics and influencing factors has important practical significance for giving full play to the potential power transmission and power supply capacity, and improving operational efficiency and the level of security and stability of the grid. Component parameters is an important factor affecting the system stability, an accurate grasp of the component parameters on the influence degree of power system transient stability and its characteristics and laws, for the grid scheduling and operational control has important practical engineering value. Based on the engineering background of the real power grid, this paper launched a profound research on the influence of parameters on the transient stability of power grid.Firstly, the definition, analysis method of power system transient stability, the research status of the influence of component parameters on transient stability and the study and application situation of trajectory sensitivity method in transient stability analysis are briefly reviewed; then the mathematical model of the system components and its characteristics and application scenario are introduced and illustrated; as well as the definition, classification and calculation method of trajectory sensitivity and th e characteristics of its application in power system transient stability analysis are summarized and analyzed.Secondly, in order to reflect the impact of component parameters on transient stability detailedly and intuitively, on the basis of analyzing the relationship between the characteristics of power angle and voltage dynamic trajectory and power system transient stability, a parametric sensitivity analysis method based on transient stability measure index is proposed in this paper, which achieved qua ntitative evaluation of the impact of component parameters on the transient stability. Simulation result in the real power grid verified the validity of this method.Finally, this paper makes research on Hunan power grid, the perturbation theory, the trajectory sensitivity method, the parameter sensitivity analysis method are integrated used to study the influence of the parameters of synchronous generator, speed governor, excitation system, the main transmission lines and transformers on the transient stability of Hunan power grid. The results show that: parameters such as the alternating and direct axis synchronous reactance, rotor inertia time constant, electric transmission line reactance, capacitance of transmission lines to ground, transformer ratio have greater impact on transient stability of the power grid. Among them, the rotor inertia time constant increased helps to improve transient stability, the alternating and direct axis synchronous reactance, transient reactance direct axis, transmission line reactance, capacitance of transmission lines to ground decreased can improve the transient stability, transformer variable appropriately increased can also improve the transient stability. The results for the real power grid development planning and scheduling have project reference value.