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Abstract
Introduction. The paper proposes a model for a cause-oriented assessment of the operational availability of low-power grid-connected solar photovoltaic power plants (SPVPP) operating in low-voltage distribution networks. The scientific idea of the work is that the actual unavailability of the SPVPP is considered not as a single integrated downtime, but as a result of the interaction of solar generation, local load, connection point parameters, network constraints, and inverter protection logic.
Methods and materials. A hybrid physical-statistical model has been developed in which the state of the plant is described by an availability indicator KD(t), and calendar availability KDcal, availability in the potential solar generation window KDsol, network-conditioned availability KDnet, and equipment availability KDeq are presented as special cases of a unified calculation scheme. The model is calibrated based on annual monitoring data of a 10 kW SPVPP in the Khatyrchi district of the Navoi region for 2024.
Results. 613 protective shutdowns with a total duration of 306.5 hours were registered; calendar availability was 96.51%, and availability in the 2900-hour solar window was 89.43%. It was found that 433 events, or 70.6%, are associated with overvoltage in the low-voltage network. The dependence of KDcal(r) and KDsol(r) on the share of reduction in overvoltage-related shutdowns r is proposed; it is shown that reducing this group of events by 50-75% increases KDsol to 93.16-95.03%. Verification was carried out at two levels: locally – on five similar SPVPPs in the Khatyrchi district, and interregionally – on five 10 kW stations in various regions of Uzbekistan.
Conclusion. A target function, boundary conditions for sustainable operation, and an operational energy audit algorithm have been formed. The proposed approach allows moving from recording outages to diagnosing the physical cause of unavailability and selecting technically justified measures.
References
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This work is licensed under a Creative Commons Attribution 4.0 International License.
Copyright (c) 2026 Avezova, N.R., Shog‘o‘chqorov, S.Q., Qulmatov, H.H., Qudratov, A.R., Raxmatov, A.R., Siddiqov, X.Z. (Muallif)