Industrial loads are mostly inductive and hence operate at low power factor. Several methods including the installation of capacitor banks are available for improving power factor in order to reduce the kilovolt ampere (kVA) demand of the load and power loss from the power supply system. However, literatures have shown that improvement of power factor has effect on switching transients which is dangerous for industrial loads and operating personnel. In this work, we investigated the effect of improving the power factor of a power system beyond 0.8 (lagging) on switching transient levels using FUMMAN industry power network as a case study. A power factor measuring tool was modelled using the mathematical relation between power factor, reactive power and active power. The modelled equations were simulated Matlab/Simulink software (Version 7.9.0.529 ‘R2009b’). The characteristics of the system under study namely root mean square (r.m.s) voltage, peak steady state voltage, peak transient voltage and kVA demand were measured during the simulation with and without parallel connection of capacitor bank across the system. The result from the analysis showed that FUMMAN industry power network was operating at a lagging power factor of 0.8 with r.m.s voltage of 412.1 V, peak steady state voltage of 582.8 V, peak transient voltage of 701.9 V and kVA demand of 1878 kVA without the capacitor bank. However, when a capacitor bank was connected across the system and the power factor increased from 0.8 (lagging) to 0.9098 (lagging), optimised performance of the system was obtained with a capacitor bank size of 440 kVar. At lagging power factor of 0.9098, the kVA demand of the system was 1650 kVA, r.m.s voltage was 415.5 V and peak transient voltage was 749.5 V. The analysis therefore showed that increasing power factor beyond 0.8 (lagging) using capacitor banks though improves the r.m.s voltage and reduces the power loss but invariably leads to increase in switching transients which is undesired for optimised system performance.
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