This paper presents a Microcontroller based three phase induction motor protection relay. The scheme employs the Hall effect current transducers for sensing motor line currents, and an ‘Auto ranging ’ feature, in order to acquire motor line currents accurately from no load to blocked rotor current. The flexibility of ‘Operator selectable thermal current versus time (I-T) curves feature’ is incorporated in the relay software, in which using the operator fed cold curve points and the thermal time constant of the motor, the corresponding I-T cold and hot curves can be fitted by the relay Software. The relay performance, with the selected I-T curves has been studied in the laboratory by testing on a three phase, 5 h.p. induction motor and it has been observed that the relay to follow the selected I-T characteristics. © 1998 Taylor & Francis.
| dc.contributor.author | Vittal, K.P. | |
| dc.contributor.author | Fakruddin, D.B. | |
| dc.contributor.author | Raghavendra Rao, I. | |
| dc.contributor.author | Parthasarathy, K. | |
| dc.date.accessioned | 2026-02-05T11:00:33Z | |
| dc.date.issued | Microcontroller based three-phase induction motor protection relay with operator selectable thermal it curve feature | |
| dc.description.abstract | 1998 | |
| dc.identifier.citation | Electric Machines and Power Systems, 1998, 26, 1, pp. 13-26 | |
| dc.identifier.issn | 0731356X | |
| dc.identifier.uri | https://doi.org/10.1080/07313569808955804 | |
| dc.identifier.uri | https://idr.nitk.ac.in/handle/123456789/28042 | |
| dc.title | This paper presents a Microcontroller based three phase induction motor protection relay. The scheme employs the Hall effect current transducers for sensing motor line currents, and an ‘Auto ranging ’ feature, in order to acquire motor line currents accurately from no load to blocked rotor current. The flexibility of ‘Operator selectable thermal current versus time (I-T) curves feature’ is incorporated in the relay software, in which using the operator fed cold curve points and the thermal time constant of the motor, the corresponding I-T cold and hot curves can be fitted by the relay Software. The relay performance, with the selected I-T curves has been studied in the laboratory by testing on a three phase, 5 h.p. induction motor and it has been observed that the relay to follow the selected I-T characteristics. © 1998 Taylor & Francis. |