Harmonic impact of LPG-to-electric cooking substitution on Indian low-voltage networks and a hybrid GWO–DE tuned active-filter mitigation

A constraint on liquefied petroleum gas (LPG) supply through the Strait of Hormuz, the corridor through which the majority of India’s imported LPG is routed, would induce a substitution of LPG-based domestic cooking by electric alternatives. The present study evaluates the low-voltage (LV) distribution-side power-quality consequences of such a substitution through a scenario-based simulation study. The supply-constraint scenario is treated explicitly as a what-if construct rather than as a reported event: the Hormuz-routed share of LPG imports is postulated to fall from \\(90\\%\\) to \\(35\\%\\) with domestic output raised by \\(25\\%\\) , and the resulting consumer substitution is parameterised through an adoption fraction that is swept across its full range rather than predicted. A non-trivial fraction of consumers is assumed to transition to induction cookers, induction ovens and triode-for-alternating-current (TRIAC) controlled infrared (IR) heaters, each of which is intrinsically non-linear at the point of common coupling (PCC). Device-level harmonic signatures are taken from laboratory measurements of five commercially available units purchased on the Indian retail market, giving a measured mean current total harmonic distortion of \\(78.4\\%\\) for the induction cooker, \\(71.2\\%\\) for the induction oven and \\(64.8\\%\\) for the TRIAC-IR cooktop, with the third, fifth and seventh harmonics at \\(62\\%\\) , \\(41\\%\\) and \\(28\\%\\) of the fundamental respectively for the induction cooker. A representative Indian 4-wire 415/240 V LV feeder served by a 250 kVA 11/0.415 kV transformer supplying 240 households is modelled, and the analysis is conducted using a three-phase four-wire unbalanced load-flow formulation with explicit neutral-conductor and earth-return representation, so that the random single-phase connection pattern characteristic of Indian residential feeders is captured rather than assumed away. A Monte-Carlo penetration sweep of 500 realisations per adoption fraction is conducted for adoption rates ranging from \\(\\eta = 0.1\\) to \\(\\eta = 0.8\\) . Under the unbalanced formulation the PCC voltage total harmonic distortion (THD) is found to rise from a baseline of \\(3.1\\%\\) to \\(12.9\\%\\) at \\(\\eta = 0.6\\) , the feeder current THD from \\(14.2\\%\\) to \\(58.7\\%\\) , the neutral current from 0.11 to 1.87 times the mean per-phase RMS current owing to the combined effect of zero-sequence triplen amplification and fundamental-frequency phase imbalance, and the transformer K-factor from 1.18 to 5.43, the last reducing the effective transformer capacity to approximately \\(79\\%\\) of nameplate. A hybrid Grey Wolf Optimiser–Differential Evolution (GWO–DE) tuned shunt active power filter (SAPF) is proposed for mitigation. The proposed scheme restores the PCC voltage THD to \\(2.6\\%\\) , the feeder current THD to \\(5.6\\%\\) , the neutral current to 0.47 times the mean per-phase current and the K-factor to 1.62, with a DC-link voltage ripple of \\(1.8\\%\\) and a settling time of 21.4 ms. Against four recent metaheuristics (WOA, AOA, GTO and RIME) evaluated under an identical objective-evaluation budget, the proposed hybrid attains the lowest best objective and the fewest iterations to convergence. The controller tuning has been validated on a controller-hardware-in-the-loop platform and on a 5 kVA laboratory prototype, which reproduce the simulated indices to within 0.4 percentage points of voltage THD. The hybrid optimiser converges in 43 iterations against 78, 69 and 92 iterations for standalone GWO, DE and PSO respectively, attaining a best objective value of 0.097. A whole-life economic assessment incorporating SAPF inverter conduction and switching losses, standby consumption and annual maintenance yields a payback period of 6.8 to 9.1 years. The findings quantify the distribution-side power-quality exposure associated with rapid electric-cooking substitution and provide a mitigation strategy for distribution utilities.