Dynamic Response of a Feedback Thermoresistive Electrical Substitution Pyranometer

Autor:	Raimundo C. S. Freire, P.C. Lobo, Amauri Oliveira, Antonio Marcus Nogueira Lima, J. S. Rocha Neto, G.S. Deep
Rok vydání:	1998
Předmět:	Actinometer Wheatstone bridge Pyranometer Materials science Input offset voltage Renewable Energy Sustainability and the Environment business.industry Amplifier Energy Engineering and Power Technology Temperature measurement law.invention Optics Transducer Radiant flux law business
Zdroj:	Journal of Solar Energy Engineering. 120:126-130
ISSN:	1528-8986 0199-6231
DOI:	10.1115/1.2888055
Popis:	Solar radiant flux at the terrestrial surface is measured by pyrheliometers for direct (including circumsolar) radiation at normal incidence, and by pyranometers for total and sky radiation from a hemisphere. Calorimetric pyranometers use plane black thermal sensors which absorb solar radiation. If a thermoresistive transducer (sensor-detector combination) is used, the temperature measured is nearer the true value than for thermoelectric transducers. More importantly, the measurement of electrical power is much more accurate than the measurement of temperature. In commercial platinum (thermoresistive), thin film thermometers, the substrate produces transducer time constants an order of magnitude larger than for the best thermoelectric transducers. Use of an electronic amplifier with the thermoresistive sensor, forming one arm of a Wheatstone bridge and arranged in a negative feedback configuration, can reduce the overall response time considerably. Theoretical formulations of instrument response, taking into account the amplifier input offset voltage, are presented and the response time is estimated.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::0a8f0dddcef14f85fccac9b8c01ca536 https://doi.org/10.1115/1.2888055 Zobrazit plný text záznamu