Characterization and capture of photovoltaic system losses due to nonuniform conditions

摘要: This research develops a comprehensive methodology and model for accurate prediction of power losses caused by nonuniform electrical characteristics operating conditions in grid-tied photovoltaic systems, as well the potential increased energy capture systems which employ sub-array optimizers (microconverters or microinverters). Investigation these topics provides framework more loss modeling determination optimizers' value variety scenarios, enabling future PV maximizing built environment. A custom multitracer, records simultaneous module-level I-V curves, is designed to collect data on 27 installations Southwestern U.S. The resulting measured dataset, including over 500 modules crystalline silicon thin film technologies, indicates that commonly-used, single diode generator methodologies often incorrectly predict performance at low medium light levels. new parameters are proposed, demonstrating an improved way incorporate increase accuracy arrays. unique, detailed annual simulation environment system developed, allowing user-input cell level. It specifically mismatch partial array shading, use mitigate related losses. simulations, combined with curve used module-to-module variation each monitored array. losses, representing may be directly recovered using optimizers, moderately most tested Annual simulations realistic shading scenarios configurations show percent 2-3 times incident lost partially shaded Sub-module even module level nearly same opportunities simplification. Arrays can recover 30-45% loss. In example advantageous levels, adding little benefit string bypass sub-module