دانلود رایگان مقاله انگلیسی رویکردی برای تحلیل پایداری ولتاژ پویا برای ادغام پارک ها - IEEE 2018

Abstract:

In this study, an improved voltage stability index that can evaluate the unstable behaviour of the power system with doubly-fed induction generator (DFIG) wind parks integration is presented. Accordingly, voltage stability constrained optimal power flow (VSC-OPF) is studied including an improved impedance-based (IB) index. In particular, this study has two main contributions. First, it proposes an IB index with consideration of DFIG capability curve limits and on-load tap changer (OLTC) behaviour. The proposed voltage stability index can detect precisely the voltage collapse, especially after the occurrence of a given contingency due to the dynamic elements of the system. In this study, a model is proposed for DFIG capability curve limits that can be integrated to the internal circuit of the generator. In particular, the proposed model can be appended to impedance matching theory. Furthermore, the OLTC model is added to this index. The index uses the concept of the coupled single-port circuit. The second contribution proposes a VSCOPF with an improved IB index that is also compared with three existing VSCOPF methods in stressed and single line outage conditions. These approaches are tested and validated on modified WSCC test system, IEEE 39-bus, IEEE 57-bus and Polish 2746-bus systems.

6 Conclusion

In this paper, we propose the improved IB VSI, which can detect precisely the voltage instability with high penetration of wind turbine. This index can model the DFIG reactive power limit and it uses the concept of the coupled single-port circuit. A VSC-OPF is carried out with the proposed index. The improved model is based on a variable virtual impedance and it is adaptable with DFIG reactive behaviour. The paper proposes also the modelling of the OLTC in the IB index if it is available in the system.

Several dynamic and static studies are proposed to demonstrate the effectiveness of the proposed model. They have been divided into two parts that are voltage stability monitoring and VSC-OPF. By applying the proposed model to voltage stability monitoring, the accurate voltage instability detection has been depicted in three case studies. In particular, the comparison between improved and traditional IB index represents the method performance. The proposed VSC-OPF also has been compared between improved IBindex, L-index, VCPI and MSV. The results reveal that the improved IB index has the lowest operating cost. The results can also produce different scenarios with several objective functions and load profiles. Hence, ISO can identify the proper strategy in these different scenarios. In future works, this VSC-OPF could consider the characteristics of an electricity market such as reactive power market. Therefore, it would be compatible with the electricity market regulations.