基于改进多馈入有效短路比的受端交直流混联电网STATCOM定容方法

STATCOM capacity-determine method based on modified multi-infeed effective short-circuit ratio in receiving-end AC/DC hybrid grid

针对传统多馈入有效短路比无法计及STATCOM动态响应过程的缺点,文章基于戴维南动态等值方法提出了一种考虑STATCOM接入影响的改进多馈入有效短路比,该指标通过BPA动态仿真求取系统等值阻抗,能够更准确地描述受端系统的强度。此外根据所提出的改进多馈入有效短路比,文章以提升受端交直流混联电网安全稳定性为目标,从总体性和平衡性两方面量化了STATCOM的无功补偿的效果,并建立了一套完善的STATCOM定容方法。利用实际电网算例证明了所提指标和方法的有效性。

Aiming at the shortcomings of the traditional multi-infeed effective short-circuit ratio that cannot account for the dynamic response process of STATCOM,this paper proposes a modified multi-infeed effective short-circuit ratio based on Thevenin’s dynamic equivalence method,taking the impact of STATCOM into account.Such index can be obtained by working out the system equivalent impedance with BPA dynamic simulation,which will better describe the strength of the receiving-end system.Moreover,according to the proposed modified multi-infeed effective short-circuit ratio,aiming at improving the safety and stability of the receiving-end AC/DC hybrid grid,this paper quantifies the reactive power compensation effect of STATCOM from two aspects of totality and balance,a complete set of STATCOM capacity-determine method is established.Finally,the effectiveness of the proposed index and method are verified by an actual grid calculation example.