News & Updation
330KV NIGERIA ELECTRIC POWER SYSTEM OPTIMISATION BY PRIMAL-DUAL INTERIOR-POINT TECHNIQUE FOR TWO DIFFERENT POWER POOLS.
*Dr. C. I. Obinwa
Optimization technique that is applied in 330 kV and other Extra High Voltage Networks are many but, all in all Primal-Dual Interior-Point (PD-IP) technique currently proves most successful. . The Technique solves load flows which are non-linear with both equality and inequality constraints at the same time thereby saving time and saving the system from encountering problems due to delays in faults clearing. The existing solves one constraint after the other and has more than six (6) iterations before converging, while the developed method converges after first iteration. The developed technique guarantees higher system power generation with, higher loading and higher system stability. With these advantages PD-IP is most cherished and it is obtained by applying the non-negative Primal Variables, “S” and “z” into the problem formulation to transform the Inequality constraint part to Equality constraints and subsequently apply another non-negative Dual Variables, “” and “v” together with Lagrange multiplier “?” to solve optimisation. Optimisation is solved by incorporating, Barrier Parameter “” which ensures feasible point(s) exist(s) within the feasible region (INTERIOR POINT), Damping Factor or Step length parameter “?”, Step Size ?Y, in conjunction with Safety Factor “” (which improves convergence and keeps the non-negative variables strictly positive) are used for updating variables (Y1=Y0+??Y0). If initialised variables fail convergence test, iteration starts with the updated variables. The problem formulation is done economically through minimisation of cost of power generation; min C(PG)= ?+?PG+?PG2, g(x)=0, stands for conventional power flow equation and other equality constraints, which is represented as; PGPDloss=0 and h ? h(x) ? ?, stands for operating limits on the system, which is represented as PGmin ? PG) ?PGmax. The numerical algorithms of the method runs; Step Zero (Initialisation), Step One (Compute Newton Direction ?Y), Step Two (Update Variables), Step Three (Test for Convergence). Studies with results and analysis of improved performance by using PD-IP technique on the 330KV Bus are discussed with higher system stability obtained.[Full Text Article]