A study on low voltage ride-through capability improvement fordoubly fed induction generator

• Main Authors: Xiao-Chiu Lin, 林筱秋
• Other Authors: Chan-Nan Lu
• Format: Others
• Language: zh-TW
• Published: 2010
• Online Access: http://ndltd.ncl.edu.tw/handle/91142200464868888674

碩士 === 國立中山大學 === 電機工程學系研究所 === 98 === Since large scale unscheduled tripping of wind power generation could lead to power system stability problem. Thus network interconnection regulations become more rigid when the wind power penetration reaches a non-neglible portion of the total power generation. This thesis presents a comparison of five different low voltage ride through (LVRT) capability enhancement technologies, i.e., additional rotor resistance, DC bus chopper, crowbar on rotor, the combination of above schemes, and grid voltage support by controlling grid side converter. System simulations are performed under Digsilent environment with model and control blocks provided by the package. Additional models are developed to implement the LVRT enhancement schemes studied. A Doubly-Fed Induction Generator (DFIG) with pitch control is used to simulate different system fault scenarios with different voltage sag magnitude and duration time. Simulation results indicate that different enhancement schemes provide various levels in relieving DC bus overvoltage, rotor winding overcurrent, and overspeed problems, and the method combines all tested schemes seems to provide the best result.