International Journal of Advanced and Applied Sciences, 8(5) 2021, Pages: 59-66 Contents lists available at Science-Gate International Journal of Advanced and Applied Sciences Journal homepage: http://www.science-gate.com/IJAAS.html 59 Speed control of the asynchronous motor using LabVIEW Petru Livinti * Department of Energy and Computer Science, Vasile Alecsandri University of Bacău, Bacău, Romania ARTICLE INFO ABSTRACT Article history: Received 1 October 2020 Received in revised form 20 December 2020 Accepted 19 January 2021 In this paper a comparative study on the methods of adjusting the speed of a three-phase asynchronous motor with a rotor in a short circuit was presented. For the same structure of the experimental stand used, two programs were created, implemented, and validated in LabVIEW. For the first method, the program in LabVIEW was made with the PI (proportional- integrative) controller and for the second method, the program in LabVIEW was made with the Fuzzy Logic controller. Following the analysis of the resulting graphs, it was found that the speed control system made with the fuzzy logic controller ensures an increase in its performance compared to the speed control system made with the conventional PI type controller. The indicial responses of the adjustment system of the three-phase asynchronous motor speed with PI controller or Fuzzy Logic controller have been determined in real-time by means of the experimental stand. The override of the speed adjustment system is decreased from the value of 26.9% corresponding to the PI controller to the value of 2.3% corresponding to the Fuzzy Logic controller and the duration of the transient time is decreased from the value of 2.2 s related to the PI controller to the value of 0.5 s, related to the Fuzzy Logic controller. By using the Fuzzy Logic controller, the amount of electrical energy required to supply the electric drive system made with a three-phase asynchronous motor will be reduced. This three-phase asynchronous motor speed adjustment algorithm can be implemented for other electric drive systems from different industrial applications. Keywords: Three-phase asynchronous motor Fuzzy logic Speed control © 2021 The Authors. Published by IASE. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). 1. Introduction *The frequency static converters allow the modification of the electric energy parameters (voltage and frequency) by transforming the A.C. currents of constant voltage and frequency from the industrial mains supply into A.C. currents of variable voltage and frequency. The frequency static converters are used for the power supply of three- phase electric motors. Real-time ordering of the frequency static converters is realized with the microcontrollers from the Compact RIO control board structure. In works Kumar and Patnaik (2015), Aggarwal et al. (2015), and Salim (2015) was presented the speed adjustment algorithms with proportional-integrative (PI) controller or Fuzzy Logic controller that was implemented in LabVIEW for DC motors or servomotors. A comparison of the * Corresponding Author. Email Address: plivinti@ub.ro https://doi.org/10.21833/ijaas.2021.05.007 Corresponding author's ORCID profile: https://orcid.org/0000-0002-6217-5733 2313-626X/© 2021 The Authors. Published by IASE. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/) results obtained through the Fuzzy Logic controller versus the conventional PI controller for controlling the speed of the D.C. motors or induction motors has been presented in the works of Nagarajan et al. (2019), Acikgoz (2018), Shaija and Daniel (2016), Rajpoot et al. (2018) and Usha and Subramani (2018). In the works of Asija (2010), Faisal and Paliwal (2018), Kalhoodashti and Shahbazian (2011), and Manjunatha (2017); the speed adjustment algorithms with PI controllers and Fuzzy Logic controllers have been presented that were simulated in MATLAB-SIMULINK for three-phase asynchronous motors. In the study of Livinti and Pusca (2012), a speed control algorithm with a PI controller implemented in LabVIEW for the three- phase asynchronous motor was presented. The purpose of this work is to present two methods for adjusting the speed of a three-phase asynchronous motor with short-circuit rotor in real-time, supplied from a static frequency converter. In the case of the first method, a conventional controller of proportional-integrative type (PI) is used, whilst in the case of the second method, a Fuzzy Logic controller is used. If the designing of the PI controller requires the determination of the transfer function