Power Flow Study For Transient Stability Problems And Its Enhancement Using Thyristor Controlled Series Capacitor (Case Study In Gilgel Gibe-Ii To Sebeta-Ii High Voltage Transmission Line)

Abstract

The Stability Problem Is An Important Issue That Explains The Stable And Reliable Operation Of An Electrical Power System. A Stability Problem Is Either A Steady-State Or Transient Stability Problem. An Increase In Power Demand In Recent Years Has Developed A Number Of Challenges For Power System Engineers, For Increasing The Power Transfer Capability Of The Already Installed Transmission System Without The Expansion Of The Existing Or Building New Transmission Networks. Conventional Methods Adopted For The Enhancement Of Transient Stability Include Circuit Breakers, Fast-Acting Exciters, And Reduced Total Transfer Reactance Of The System. However, The Modern Technology Flexible AC Transmission System Devices Such As Thyristor Controlled Series Compensator (TCSC) Can Help To Increase Power Transfer Capacity In Heavily Loaded Networks Because Of Their Capability To Control Power Flow Effectively. This Is Where The TCSC Device Is Very Useful Because Of Its Low Initial Cost As Compared To Setting Up Completely New Transmission Networks. The TCSC Technology Makes Use Of The Already Installed Generating And Transmission Systems With Minimum Line Losses And Maximum Use Of The Existing System. The Most Common Causes Of Transient Stability Are Fault, Lightning, Power Line Switching, And Others. The Severity Of Problems That Occur Due To The Source Of Transient Disturbances Occur In A Transmission Line Can Be Mitigated By Using FACTS Device Controllers. Thus, Taking The Consideration Of The Above Facts Into Account In Resolving The Transient Stability Problems In The High Voltage Transmission Systems, This Thesis Aimed To Focus On Flexible AC Transmission System Controller (FACTS) Devices To Be Used As An Effective Utilization And Minimization Means Of Power Losses In The Transmission Line. This Controller Improves The Performance Of Transient Stability In The Transmission Line. Facts Devices Are Best For Steady-State, Dynamic, And Transient Stability Improvement. From The Different Types Of FACTS Devices, This Thesis Has Used Thyristor Controlled Series Capacitor Facts Device Because Of Its Effectiveness, Cost And Used For Many Applications Like Transient And Dynamic Stability Improvement, Voltage Control, Etc. For Further Improving The Transient Stability Margin (TSM), Facts Devices Have Been Employed, And The Results Of Gilgel Gibe (GG)-II To SEBETA-II Transmission Line Have Been Obtained And Verified Using MATLAB Simulink Software. From The Results, The Power Transfer Capacity Is Increased From 417.89MW To 611.38MW With TCSC And The Suitability And Effectiveness Of The Selected Facts Device For Enhancing The Transient Stability Of The Power System Have Been Discussed And Optimal Results Are Obtained.