Enhancing power system loadability using improved PSO/ABC, ABC/BFO, PSO/BFO AND CS/BFO hybrid techniques

Abstract Nowadays, power grids operate closer to their loadability limits; hence, the power systems static voltage stability assessment becomes an essential task in planning and operating for electric power systems to prevent voltage instability and its eventual collapse. In this paper, the improved PSO/ABC, ABC/BFO, PSO/BFO AND CS/BFO hybrid techniques are applied for optimal placement and parameter setting of UPFC device for enhancing loadability with the aim to prevent voltage collapse on power system network. Voltage collapse phenomenon has remained an operational problem yet to be solved by power system engineers. The performance of the proposed hybrid methods is examined on the practical Nigerian 56-bus network for voltage stability and loadability improvement. The simulation results have shown that ABC/BFO technique is better than BFO/PSO by 3.44 $$\%$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>%</mml:mo> </mml:math> in improving voltage stability and loadability margin of power system, $$\text{PSO}/\text{ABC }$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mrow> <mml:mtext>PSO</mml:mtext> <mml:mo>/</mml:mo> <mml:mtext>ABC</mml:mtext> <mml:mspace/> </mml:mrow> </mml:math> gives additional improvement of 4.07 $$\%$$ <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"> <mml:mo>%</mml:mo> </mml:math> , totalling 7.51% and lastly BFO/CS technique improved voltage stability and load margin of power system further by 5% totalling 12.51%. Also this research revealed that the smaller the gamma value the better the UPFC contribution to voltage stability enhancement. BFO/CS technique yielded the smallest gamma values of 0. 74532 and 0.830913 in both Nigerian practical network and IEEE 14-bus network as shown in the analysis.