Study Of Multi-Parameter Optimization Of PSS Based On The Entire Power Grid Frequency Stability

Modern power system the size and complexity of being a significant increase, taking into account the economic and environmental restrictions on the power system power transmission level of demand higher and higher, with a large unit, EHV grid for the characteristics of the large-scale electricity the rapid development of systems to improve the stability of the system is running into the safety of the growing importance of the urgency of the study.The power system in operation for various reasons sometimes appear every few minutes to dozens of very low frequency of spontaneous frequency oscillation system, when the oscillation will seriously damage the internet system of parallel operation, causing massive power outage, to the national economy caused great losses. Research shows that low-frequency oscillations can provide the necessary additional excitation control of the additional damping to be inhibited, the practice shows that in a specific unit to install power system stabilizer (PSS) is restrain the low-frequency oscillations of cost-effective way. But for PSS with the multi-unit system, if no suitable PSS parameters, PSS will not be able to effectively play its role in damping low-frequency oscillation, the oscillation could even help by starting role, based on the power grid frequency stability of the entire multi-PSS parameter optimization and check on the power system to improve security and the economy are of great significance.In this paper, the disturbance caused by the power system for small, low-frequency oscillations of the mechanism and measures to curb based on the analysis of the power system's stability principle was introduced, the current parameters of the PSS optimization methods were compared, PSO algorithm is simple, fast convergence, and other advantages, can effectively address the high-dimensional, nonlinear, multi-peak complex optimization problems, a new potential evolutionary algorithm. In this paper, the introduction of cross-operation to improve the PSO algorithm, compared to basic PSO algorithm is faster convergence rate and overall search capabilities, can be effective access to PSS parameters optimization global optimal solution.