Measurement of heat losses on the milking machine electric motor at various regulations of vacuum using methods of thermal imagery

• Published in: Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis Vol. 62; no. 5; pp. 1007 - 1014
• Main Authors: Kudelka, J., Mendel University in Brno (Czech Republic). Dept. of Agriculture, Food and Environmental Engineering, Fryc, J., Mendel University in Brno (Czech Republic). Dept. of Agricultural, Food and Environmental Engineering, Travnicek, P., Mendel University in Brno (Czech Republic). Dept. of Agricultural, Food and Environmental Engineering
• Format: Journal Article
• Language: English
• Published: Mendel University Press 2014
• Subjects: AIR TEMPERATURE; ANALISIS DE IMAGENES; ANALYSE D'IMAGE; CALOR; CAPTEUR; CARACTERISTICAS DE LA MAQUINARIA; CARACTERISTIQUE DU MATERIEL; CHALEUR; control valve; CONVECCION; CONVECTION; CZECH REPUBLIC; electric motor; ELECTRIC MOTORS; ELEMENT DE MATERIEL; ELEMENTOS DE MAQUINARIA; ENERGY LOSSES; EQUIPMENT CHARACTERISTICS; EQUIPMENT PARTS; frequency converter; HEAT; HUMEDAD RELATIVA; HUMIDITE RELATIVE; IMAGE ANALYSIS; IMAGENES; IMAGERIE; IMAGERY; MACHINE A TRAIRE; MAQUINAS DE ORDENO; MATEMATICAS; MATHEMATICS; MATHEMATIQUE; MEASUREMENT; MEDICION; MESURE; milking machine; MILKING MACHINES; MOTEUR ELECTRIQUE; MOTORES ELECTRICOS; PERDIDAS DE ENERGIA; PERTE D'ENERGIE; PROPIEDADES TERMICAS; PROPRIETE THERMIQUE; RADIACION TERMICA; RAYONNEMENT THERMIQUE; RELATIVE HUMIDITY; REPUBLICA CHECA; REPUBLIQUE TCHEQUE; rotary vacuum pump; SENSORES; SENSORS; TEMPERATURA; TEMPERATURA DEL AIRE; TEMPERATURE; TEMPERATURE DE L'AIR; TEMPS; thermal camera; THERMAL PROPERTIES; THERMAL RADIATION; TIEMPO; TIME
• ISSN: 1211-8516; 2464-8310
• DOI: 10.11118/actaun201462051007

To ensure the desirable vacuum in the milking machines, use is currently made predominantly of rotary vacuum pumps. These vacuum pumps are driven by a squirrel-cage induction motor. Until recently, the vacuum in the system to achieve the required value was controlled by a main control valve sucking in ambient air into the system. During the milking process itself and during other activities (flushing, sanitation), this control method consumed a large amount of electricity. The technical solution to electricity demand reduction was introduced with the emergence and development of frequency converters. The frequency converters control the operation of the asynchronous electric motor so that the actual delivery of the vacuum pumps equals the volume of air sucked into the vacuum pipe. The motor supply by the frequency converter brings about a host of adverse phenomena. This paper is dedicated to motor heating and heat losses on the surface of the electric motor at different regulations of vacuum in milking machines. The objective of the paper is to determine the immediate specific heat flows along the surface of the electric motor of the milking machine during milking using a control valve regulation and a control using the frequency converter, and compare the resulting value. The specific heat flows were determined by means of a non-traditional method of temperature field measurement using a system of thermal imagery. The calculated and measured data obtained from both these systems were statistically evaluated and compared. Use was made of a milking machine located in the cooperative Hospodarske obchodni druzstvo (HOD) Jablonov.