On electromagnetic and mechanical interactions in asynchronous machines

A detailed analysis of electric power and electromechanical interactions in asynchronous machines is carried out from the standpoint of the fundamental laws of electrophysics, analytical mechanics and theoretical electrical engineering. A structural and logical scheme (roadmap) of the movement of electromagnetic energy from the engine power source to the rotation of the shaft and the drive mechanism rigidly connected to it is proposed. Each stage of the energy movement is accompanied by an explanation of the causes of the movement with references to the laws and postulates of electrophysics and electromechanics that form these stages. The formation of the fundamental law of motion of mechanical energy is shown, accompanied by potential (external to the engine), kinetic (internal mechanical) and energy associated with thermal losses of the rotating system “engine – drive mechanism”. At the same time, the physical foundations of the formation of the corresponding torque and braking moments are shown. The mistakes made in some textbooks in the formation of mathematical models of asynchronous motors are determined. The physical foundations of the formation of external (potential) energy and the power consumed by the engine from an external source are investigated. It is confirmed that the main reason for the rotation of the motor rotor is the Ampere force formed by the corresponding law of electrodynamics. Analytical dependences are given that allow calculating both the magnitude of the force and the direction of rotation of the engine shaft. According to the magnitude of the force acting on the rotor, the corresponding energy and braking torque are easily determined. The conditions for the formation of the nominal rotation speed of the rotor are considered. The process of forming the kinetic energy of the rotating inertial mass of the “motor – drive mechanism” system is shown. Graphs of changes in all types of energy within the framework of the law of conservation and transformation of energy are given, which allow us to visually analyze the processes in the machine. Conclusions are drawn about a significant expansion of capabilities in calculating the operating modes of the machine.