The effect of greenhouse irradiators on the load factor of step-down transformers

Abstract

The aim of the work is to determine the permissible load factors of step-down transformers when powering various types of greenhouse irradiators. All examined irradiators have nonlinear volt-ampere characteristic and generate upper current harmonics. The object of research are greenhouse illuminators with high pressure sodium lamps, induction and light-emitting diodes greenhouse illuminators (LED) with active and passive power factor. The permissible load factors of transformers are calculated using obtained data: for high-pressure sodium lamp light is 0.95 max; for LED lamps with active power factor corrector – 0.76 max; for LED lamps with passive power factor correction – 0.59 max; for electrodeless lamp light – 0.98 max. To reduce current harmonics in systems with LED lamps and to increase the load factor of transformers, it is necessary to apply special devices – active or passive harmonic filters. For greenhouse irradiators with sodium lamps and induction irradiators, the use of harmonic filters is not required.

Digital technologies for monitoring and implementation of smart diagnostics of the isolation of power supply systems with isolated neutral in the operating mode

“…Four of these cases led to a complete shutdown of the production. The existing methods of detection and localization of damage sites are problematic and take a lot of time, since the inability to diagnose these damages in advance affects [8]. The introduction of the proposed method into the production process will reduce the time and minimize losses.…”

“…The currently used methods of thermal imaging and ultrasonic testing do not allow to accurately identify the cause of accidents in distribution networks [4,5,6]. The current search generators, due to their low power, cannot cover the entire section of the diagnosed circuit [7,8,9]. A phase-to-ground fault is abnormal and dangerous for a number of reasons:…”