Research On The Simulation And Application Of STATCOM In Multi-machine Power Systems

As one of the important members of FACTS (Flexible AC Transmission System), STATCOM (Static Synchronous Compensator) has advanced control performance and good compensation effect. It plays very important roles in voltage maintaining, oscillation damping and improving the transient stability. In recent years, STATCOM has been actively researched and developed in all countries of the world and the application of STATCOM in power systems is becoming more and more widely. In the thesis, the controller design of STATCOM and the effect for transient stability performance of STATCOM in multi-machine power systems are emphatically studied and analyzed, based on the researches of simulation and application of STATCOM in multi-machine power systems.The principle of STATCOM is introduced in this thesis. The steady and dynamic models for STATCOM are deduced. For a typical two-area four-machine power systems with STATCOM connected at the electrical mid-point of the inter-area transmission line, the unified model for the four-machine power systems with STATCOM is established.In the thesis, a new type of multi-objective fuzzy controller combined withmulti-state linear feedback is designed for STATCOM. The multi-objective fuzzycontroller can adapt the change of variables and identify the main objective from different operating states in power systems. And thus the correct control measure can be taken and the optimum control result can be obtained. The system-level simulation model for STATCOM is established in the thesis. The reversible system PI control strategy and the multi-objective fuzzy control strategy are simulated through MATLAB, which provide theoretical basis for the application of STATCOM in multi-machine power systems.The effect on transient stability performance of STATCOM in multi-machine power systems is emphatically studied. The results show that STATCOM can greatly improve the dynamic performance and enhance the inter-area transmission capability in multi-machine power systems. The reversible system PI control strategy and the multi-objective fuzzy control strategy of STATCOM can both make multi-machine power systems obtain superior dynamic performance. But compared with the former, the latter is better.