Novel approaches to representing the speed–time characteristics of a direct start-up induction machine driving gravitational-type loads
Volume
75
Issue number
4
Article number
75402
Received
14.02.2024.
Received in revised form
16.07.2024.
Accepted
25.07.2024.
Available online
26.07.2024.
Authors
Ilija Knežević1, Tatijana Dlabač1*, Martin Ćalasan2, Maja Krčum3
1 Faculty of Maritime Studies Kotor, University of Montenegro
2 Faculty of Electrical Engineering, University of Montenegro
3 Faculty of Maritime Studies, University of Split
Corresponding author email
Abstract
On ships, practically all types of induction machine loads are present, among which those with fan and gravitational characteristics are the most common. This paper addresses the speed–time curve dependency on the direct start of an induction machine under gravitational load. The characteristic of speed–time, ω = f (t), is described through two analytical expressions. The first expression is derived using the formula for torque based on Thévenin’s equivalent circuit, while the second expression is derived from Kloss’s formula for torque. The mathematical model has been tested through simulation and experimental validation on an induction machine in laboratory conditions. Also, the paper includes a realised MATLAB program for determining the mentioned characteristics. The results show the high precision and practical applicability of the proposed analytical expressions in different working conditions.
Keywords
Mathematical modeling, Gravitational loads, Induction machine, Ship auxiliary machines, Ship’s power system