Photovoltaic emulator

Abstract

With the increasing use of photovoltaics (PV), flexible test-systems for PV testing are growing in importance. This is particularly true for low-cost photovoltaic emulationhardware devices which replicate the characteristics of a real photovoltaic (PV) panel but can be tuned to emulate different commercially available units and would allow the replication of varying environmental conditions in the laboratory. The scheme presented in this paper is very low-cost, easily expandable, readily interfaced to other control hardware and can emulate a variety of conditions with minimal setting changes. This methodology uses the output voltage of an adjustable linear voltage regulator which is controlled to replicate the characteristic curve of a photovoltaic panel. Its key features are that it uses the non-linearity of a commercial IC to represent the PV panel and bump-less transfer between this non-linear stage and constant current control which is required for low-voltage outputs.

PV Emulation by using DC Programmable Sources

“…Table 3. Characteristic values of the power plant ETFOS1 for a sunny day (2 November 2014) Based on the current and voltage data at maximum power points, Table 3, and the inverter efficiency rate = 98.4 % [8], the following is obtained: P tot,DCj -DC power of both strings at the instance of time j; P ACj -AC power at inverter output at the instance of time j; W ANj -the obtained energy production at the instance of time j. The expressions used for obtaining data are listed in Table 3. (1)…”

“…Then by using simulation tools like MATLAB or Labview, these data are used as input data for developed hardware [3][4][5]. It is typical for this approach that physical quantities -currents and voltages -are scaled to quantities that are safe for handling and accessible for low cost measurements [6][7][8]. In this way, emulation of different PV modules was done, but there was lack of papers for obtaining emulation of a photovoltaic system in order to predict electricity generation.…”

Low-cost photovoltaic emulator for instructional laboratories

“…This is why majority of "low cost" emulators are actually linear power supplies. Although these emulators are rated for low power their control is relatively simple [17], [25], [26].…”

“…These systems are quite advanced and benefit from ability to be integrated into bigger measurement complexes. Analogue circuits usually used to control the linear power supply emulator at a low power rate [17], [25], [26].…”

Reconfigurable Photovoltaic Emulator for Differential Diffusion Charge Redistribution Solar Modules

“…Linear emulators [22,[33][34][35][36][37][38][39] do not have instability problems from switching intermodulation and higher order dynamics that are typical of switching-converters. Furthermore, quantization error is not an issue when analog controllers are used.…”