Improving the quality of traction electric mo-tors for electric transportation

Abstract

Problem. Despite the widespread use of asynchronous electric motors (ED) in electric transportation, they often fail to meet high reliability requirements. This is primarily due to their operation in a wide range of rotational frequencies, variable load modes, frequent stops and starts, and challenging road conditions. These factors result in significant vibrations of traction asynchronous EDs, leading to reduced reliability and service life. Goal: The goal of this study is to develop methods to enhance the reliability and longevity of traction asynchronous EDs by improving the design and manufacturing technology of the stator housing and rotor of the electric motor. Methodology: Analytical research methods were employed to investigate approaches for improving the quality of traction electric motors for electric transport. Experimental research methods were used to determine the technical condition of EDs based on their vibrodiagnostic parameters. Statistical methods were utilized to process experimental data. Results: Vibration levels, which are indicative of the technical condition of EDs, were selected as the primary criterion for assessing their quality. The proposed design and manufacturing technology for asynchronous electric motors enable the following: increased manufacturing and assembly precision of EDs, simplified assembly process, reduced number of sorted parts during inspection and bearing replacement, and the development of an asynchronous traction ED with a power capacity of 90 kW and a rotational frequency of 3000 rpm, meeting class D requirements with permissible vibration levels. Originality: This study presents developed methods for increasing the reliability and longevity of traction asynchronous EDs through experimental approaches. The one-sided arrangement of base surfaces in the stator housing and the attachment of rotor bearing units enabled the production of a vertical ED assembly consisting of two independently controlled units: a housing with a shield and a rotor with bearing units. Practical Value: The achieved reduction in vibration levels allows for a predicted 2-3 times increase in the lifespan of the developed ED, depending on operating conditions. Furthermore, the created ED meets all environmental standards' requirements for vibration levels.