Silniki indukcyjne jednofazowe o podwyższonej sprawności i mocy znamionowej 7,5 oraz 10 HP

In the paper is described four prototype one-phase motors rated power 7,5 and 10 HP designed and manufactured in Electrotechnical Institute. Motors are designed according to NEMA standards for rated frequency 60 Hz. On account of rated power increase in this motors the special windings with non-uniform distribution of turns are applied. The windings are optimized on account of criterion of possible uniform slot filling by not exceed 3 % content of magnetomotive force third harmonic. For this motors was designed an especial auxiliary start capacitor switch. As actuator is utilized the pair of push-pull connected thyristors. As analyzed parameter for the electronic system is utilized the voltage on the run capacitor. The switch include an unique precision comparator with floating reference voltage. Such solution enabled accurate determination of switching moment by network voltage fluctuation and voltage drops by motor start. Prototype motors was tested and test results indicates, that all motors have better efficiency according to standard motors manufactured by leading American manufacturer and only about 1 % lower as Super-E series motors manufactured by this manufacturer. The paper presents the main motors parameters obtained from tests and also a comparison between tests and calculation results.