DFIG风电机组串联耦合补偿低压穿越研究

发布时间：2018-12-18 14:37

【摘要】：双馈风电机组(doubly fed induction generator,DFIG)在电网电压故障以及故障恢复作用下的磁链变化将导致转子过电压或过电流,威胁转子侧的变换器。采用串联耦合补偿(series coupled compensation,SCC)的新型电压穿越方案,SCC通过耦合变压器串接在发电机输入端,它能克服电网多种故障对风电系统的影响。提出的控制策略有如下优势:能削弱故障下机组定子、转子电流暂态成分,克服了定、转子绕组不平衡发热的问题,延长了风电机组使用寿命;在电网故障下发电机组仍能平稳输出有功、无功功率;在整个故障运行过程中,DFIG系统转子侧变换器始终可控,从而为故障电网提供无功功率支持成为可能。在电网对称和非对称故障条件下,采用PSCAD/EMTDC建立了1MW DFIG风力发电系统模型,仿真结果表明该控制方案可以提高DFIG的故障穿越能力。
[Abstract]:The flux change of double-fed wind turbine (doubly fed induction generator,DFIG) under the action of voltage fault and fault recovery will lead to the overvoltage or overcurrent of the rotor which threatens the rotor side of the converter. A novel voltage traversing scheme with series coupling compensation (series coupled compensation,SCC) is adopted in which SCC is connected in series through coupled transformers to the generator input. It can overcome the influence of various faults on the wind power system. The proposed control strategy has the following advantages: it can weaken the transient components of stator and rotor current, overcome the problem of unbalanced heating of stator and rotor winding, and prolong the service life of wind turbine; The generator can still output active power and reactive power stably under the fault of power grid. During the whole operation of the fault, the rotor side converter of DFIG system is always controllable, so it is possible to provide reactive power support for the fault power network. The 1MW DFIG wind power system model is established by using PSCAD/EMTDC under symmetrical and asymmetric fault conditions. The simulation results show that the proposed control scheme can improve the fault traversing capability of DFIG.
【作者单位】：东南大学电气工程学院;
【基金】：国家重点基础研究发展计划项目(973项目)(2013CB 035603) 国家自然科学基金项目(51137011,50977011)~~
【分类号】：TM614

【参考文献】