Method and system for controlling rotor speed of motor

Abstract

The invention relates to the technical field of motor control and discloses a method and system for controlling the rotor speed of a motor. The method comprises the following steps of S1, acquiring the operation information of the rotor of a motor in real time; S2, determining whether it is necessary to cut off the power supply of the motor according to the acquired operation information; when theobtained speed value is less than a set value 1, firstly reducing the power supply voltage and current of the motor and performing a time delay; when the time of reducing the supply voltage and current is greater than the predetermined time, comparing the obtained speed value with a set value 2; when the obtained speed value is equal to the set value 2, performing initialization to restore the normal power supply of the motor; and when the obtained speed value is less than the set value 2, cutting off the power supply of the motor. According to the above technical solution, when an impeller is actually used, an obstacle instantaneously blocks the impeller to lower the impeller speed is lowered such that the motor cannot be braked by mistake; the motor is braked and prevented from being burnt out only when the impeller is stuck and the speed continuously decreases.

Description

technical field [0001] The invention relates to the technical field of motor control, more specifically, it relates to a method and system for controlling the rotational speed of a motor rotor. Background technique [0002] A motor is an electromagnetic device that converts or transmits electrical energy according to the law of electromagnetic induction. The motor is represented by the letter M in the circuit. Its main function is to generate driving torque. As a power source for various machines, its main function is to convert electrical energy into mechanical energy. [0003] When the current motor is applied to the chimney to drive the impeller to rotate, the motor may be burned because the impeller may block obstacles during work. Therefore, the solution to this problem in the prior art is mainly by installing a rotational speed sensor to detect the rotational speed of the impeller, and when the rotational speed sensor senses that the rotational speed of the impeller d...

AI Technical Summary

Problems solved by technology

[0004] However, in the actual application process of the above-mentioned method of cutting off the power supply, since the actual chimney is exhausting smoke, there are easily large obstacles in the chimney. When the obstacle is discharged from the chimney, it touches the impeller and will Causes the speed of the impeller to drop to a certain speed instantly, and then when the obstacle is discharged from the chimney, the speed of the impeller returns to the original speed

When the above-mentioned speed sensor system is installed, the speed sensor senses the instantaneous speed drop when the obstacle is discharged from the chimney, which will also cause the power supply of the motor to be cut off, which requires people to turn on the motor again, which is troublesome

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