shaorc

maychang posted on 2019-1-17 09:36 Since we don't know the drive structure and the permanent magnet synchronous motor winding structure, it is difficult to specifically analyze the back electromotive force on the motor stator winding...

Thank you again, teacher. How do you understand the moment of inertia mentioned above? I often hear it but don't know what it means.

maychang

shaorc posted on 2019-1-17 10:29 Thank you again, teacher. How to understand the moment of inertia mentioned above? I often hear about it but don’t know what it means

The moment of inertia is a mechanical concept. In mechanics, there is the concept of mass. When an object is subjected to a certain force, it will produce acceleration. The larger the mass of the object, the smaller the acceleration generated under the action of a certain force. We say that under the action of a certain force, the acceleration is inversely proportional to the mass of the object. If the object is not in free motion, but rotates on a fixed axis. Then under the action of a certain torque, angular acceleration (the differential of angular velocity with respect to time) will be generated. The larger the moment of inertia of the object, the smaller the angular acceleration generated under the action of a certain torque. We say that under a certain torque, angular acceleration is inversely proportional to the moment of inertia. Intuitively, when an object rotates about a fixed axis, the greater the moment of inertia, the more difficult it is to accelerate or decelerate its rotation.

maychang

shaorc posted on 2019-1-17 10:29 Thank you again, teacher. How to understand the moment of inertia mentioned above? I often hear it but don’t know what it means

The moment of inertia is not only related to the mass of the object, but also to the position of the axis of rotation. For a uniform circular disk, the axis of rotation is perpendicular to the disk surface and passes through the center of the disk, or the axis of rotation is parallel to the disk surface and passes through the center of the disk. In both cases, the moment of inertia of the disk is different. If the axis of rotation is perpendicular to the disk surface and passes through the edge of the disk, the moment of inertia of the disk is greater. As for the calculation of the moment of inertia, it is omitted because it requires the use of multiple integrals.

maychang

shaorc posted on 2019-1-17 10:29 Thank you again, teacher. How do you understand the moment of inertia mentioned above? I often hear it but don’t know what it means

The moment of inertia should be mentioned in the course of "General Physics". For example, Chapter 4 of Volume 1 of Cheng Shouzhu Jiang Zhiyong's "General Physics" is "Rotation of Rigid Bodies".

shaorc

maychang posted on 2019-1-17 10:47 Moment of inertia should be mentioned in the course of "General Physics". For example, Cheng Shouzhu and Jiang Zhiyong's "General Physics" Volume 1, Chapter 4 "Rotation of Rigid Bodies".

Thank you, I will go to read the book now