An Optimal Approach to Voltage Collapse Margin in Nigerian Power System
By Leonard Onyedikachukwu Oluka
Published: October 28, 2017
Uploaded by: Leonard Onyedikachukwu Oluka
Controlling and monitoring of reactive power and voltage remains a great challenge faced in the power system operation of Nigeria that has continuously resulted in voltage collapse. Persistent increases in quest for power and the consequent rise in reactive power for support of voltage transfer as loads rises is insufficient to be injected by generators. The need for an approach to voltage collapse margin which is to return back the system to steady state by injection/compensation of reactive power on the transmission lines becomes urgent with other use of tap-changing transformers and load shedding strategies. These compensators which are presented in this work are SVC, STATCOM, TCSC, SSSC and UPFC are the approaches used. PSAT software which makes use of Newton-Raphson’s iterative method was used to simulate the existing 28-bus system of Nigeria which displayed high accuracy and converged in few iterations. SVC and STATCOM were first used separately to compensate bus1 (0.9673pu) while TCSC, SSSC and UPFC were later used separately to compensate the system. Results obtained showed that the use of dynamic shunt compensators (SVC and STATCOM) maintained the bus 1 voltage at 0.9673pu while the use of series compensators (TCSC, SSSC and UPFC) slightly maintained a power flow of 80MW and bus 1 voltage at 0.9673pu after several increases in loadings. It is with this that the research work presents the use of series compensators on the transmission lines as the optimal approach to voltage collapse margin in Nigerian Power system. An Optimal site for the placement of the series compensator is at Bus 8 (Jos) and Bus 9 (Gombe) which have the lowest loss of sensitivity index. The installation of any of the series compensators in Nigeria power network keeps the system in steady state at all times.
About the Author
Leonard Onyedikachukwu Oluka