Voltage Stability Analysis Of Power System With Wind Farm Integration

As one of the most mature renewable energy technologies, wind power has gained rapid development around the world. With the constant enlargememt of wind farms both in capacity and scale, the influence of its integration on the operation of power system is becoming more and more serious. Security and stability problems of power system with wind farm integration have become an important research field in recent years. This paper focuses on the voltage stability analysis of power system including wind farm, and the main contents are as follows:(1) Based on the analysis of three main types of wind power generation systems and their advantages and disadvantages, the mathematical models of each module in wind power generation system were studied and derived in detail.(2) The Dynamic Link Library File LF-UPO.dll was invoked by using the User Program Interface (UPI) module in PSASP software, and the power flow calculation models of wind turbines for steady-state simulation were established. Taking a real power system connected with wind farm as calculation example, the P-V curve method was applied to analyze the static voltage stability, and the voltage stability limit points of wind farm under different operation modes were determined.(3) The eigenvalue structure analysis method (ESA) was introduced to analyze the convergent power flow Jacobian matrix of power system including wind farm. Writing the entire algorithms based on M-file environment in MATLAB software, taking the minimum module eigenvalues and the participation factors as indicators, the impact of wind farm integration on the static voltage stability of power systems was studied. The steady-state model of STATCOM was added into power flow equations and an eigenvalue structure analysis model considering STATCOM in grid-connected wind farm system was built. Taking the static stability margin as indicator, the ameliorative effects of STATCOM on the static voltage stability was investigated.(4) The Dynamic Link Library File LF-UPO.dll was invoked by using the User Program Interface (UPI) module in PSASP software, and the transient calculation models of wind turbines for dynamic simulation were established. The transient characteristics of wind turbines were simulated and analyzed first, and then a comparative study on transient voltage stability was conducted between induction generator (IG) based wind farm and doubly-fed induction generator (DFIG) based wind farm.