Research On Optimal Configuration Of Dynamic Reactive Power Compensation Device In Guangzhou Power Grid

Highly concentrated load and four of eight "west-east power transmission" HVDC transmission lines in Guangzhou, result in a typical multi-infeed AC/DC mixed receiving system. In recent years, the change of dispatching management, rapid growth of load, less reactive power and weakness support ability of voltage, the transient voltage stability problem becomes one of the most serious problems in the security and stability operation of Guangzhou power grid.Due to the large disturbance of AC system, transient voltage instability and the voltage collapse occur occasionally in large-scale AC/DC mixed receiving-end systems and usually result in commutation failure of DC inverters, dropping of bus voltage and loss of load. Consequently, it may cause serious economic losses and adverse social impact. Therefore, transient voltage stability of large-scale AC/DC mixed receiving-end systems becomes one of the key factors affecting the security and stability operation of the large-scale receiving-end power grid.As the representative of reactive power compensation devices, Static Synchronous Compensator (STATCOM) which is an important part of FACTS can compensate the reactive power fastly, smoothly and continuously to improve the transient voltage stability.The configuration of some small capacity STATCOM in load side, it not only can improve the voltage stability, but also compensate the unbalanced load, filter the harmonic and improve the load power factor, etc.As a result, the in-depth analysis of transient voltage stability of Guangzhou power grid,identification of the weak area,and configuration of STATCOM are of great significance to ensure the security and stability of the power grid.Based on the practical transient voltage instability criteria of China Southern Power Grid, the quantitative assessment indexes reflecting the seriousness of bus voltage drop is proposed in this paper.They are voltage sag severity index and voltage sag eligibility index.Some typical faults are simulated with PSD-BPA software.Then combined with the proposed indexes, the hazard area of instability and configuration of STATCOM are researched.In the end, the application effect and investment were analyzed to select the optimal program,which can effectively solve the problem of transient voltage stability in Guangzhou power grid.