Research On TCSC Dynamic Simulation Experiment And Optimization Design Of Its Monitoring System

Physical simulation experiments of TCSC device can reflect truly the operating characteristics of TCSC to a large extent in real power system. It is of great significance for the practical engineering application of TCSC to resolve the problems in time which are discovered by verifying the basic performaces and control strategies of TCSC equipment.This thesis begins with a review on TCSC engineerings applied in practical power system, following the introduction of the basic circuit topology, principle, operation modes of TCSC and a set of TCSC experimental setup. Regarding the TCSC device as the research object, the thesis is devoted to the study on the fundamental equivalent impedance characteristic considering the thyristor value, static simulation experiments on basic performances of TCSC setup, dynamic simulation experiments of control countermeasures and the optimal design of monitoring and protection system of TCSC apparatus.The medial layer impedance control of TCSC is directly related to the effectiveness of the top layer control strategies. It is observed that the fundamental impedance performance curve changes with the line current during digital simulations and physical simulation experiments, which will cause obvious errors of open loop impedance control. The formula of TCSC fundamental impedance is deduced when considering the thyristor conduction characteristic and using the line current synchronization, from which the reason why fundamental impedance performance curve changes with the line current is ascertained. By means of digital simulation analysis, the thesis points out the problems with the existed table lookup scheme, meanwhile puts forward two new meathods to look up table, and verifies the effectiveness and feasibility by physical experiments.Through digital simulations and static simulation experiments, some important properties of TCSC device are investigated, and the rationality of the design of TCSC setup and the validity of impedance control are validated. Using dynamic simulation experiments, the PID control of constant power and constant current as well as the impact of three-phase grounding fault on TCSC are studied, then the effectiveness of the top layer control strategies and protection action performance are tested. In additional, the POD(Power Oscillation Damping)controller is designed to work out the problem with the power oscillation produced by constant firing angle control and proved to be certain effect by dynamic simulation experiments.The monitoring and protection system is an important component of TCSC apparatus and related directly to the safe and reliable operation of the apparatus. The thesis proposes a new design scheme of monitoring and protection system of TCSC directing against some defect and deficiency of the extant monitoring system, which adopts real time data exchange technology, meets the demand of real-time running state monitoring, uses the ISA(Industry Standard Architecture) bus and the RS-485 network, so the new system possesses the characteristics of higher reliability, better expansibility and compatibility, solves the problems of the existed system of TCSC device, and provides a satisfactory monitoring platform for TCSC dynamic simulation experiments.