CN-114878025-B - Real-time measuring and calculating method for rotor temperature of permanent magnet synchronous motor and related equipment

CN114878025BCN 114878025 BCN114878025 BCN 114878025BCN-114878025-B

Abstract

The embodiment of the application provides a real-time measuring and calculating method and related equipment for the rotor temperature of a permanent magnet synchronous motor, which are used for improving the accuracy of the real-time measuring and calculating of the rotor temperature of the permanent magnet synchronous motor, wherein the method comprises the steps of obtaining E0, wherein E0 is the real back electromotive force line voltage value of the permanent magnet synchronous motor under constant rotating speed and no-load running under the initial temperature T0; the method comprises the steps of obtaining E2 and E2 to be the counter electromotive force line voltage value read by a frequency converter under constant rotation speed and constant load operation of a permanent magnet synchronous motor at an initial temperature T0, reading E3 by the frequency converter to be the counter electromotive force line voltage value read by the frequency converter under constant rotation speed and constant load operation of the permanent magnet synchronous motor at a current temperature T1, and calculating the current temperature T1 of a rotor of the permanent magnet synchronous motor by using E0, E2 and E3 according to a preset formula. The embodiment of the application can realize real-time measurement of the rotor temperature of the permanent magnet synchronous motor, and has high accuracy of measurement results.

Inventors

SUN QISHENG
PENG XIAOYAN
YANG KAIQIANG
CHEN QIXIN
ZHANG CHUNBO

Assignees

厦门钨业股份有限公司
西安合升动力科技有限公司

Dates

Publication Date: 20260508
Application Date: 20220613

Claims (10)

1. The method for measuring and calculating the temperature of the rotor of the permanent magnet synchronous motor in real time is characterized by comprising the following steps of: E0 is obtained, wherein the E0 is a real counter electromotive force line voltage value of the permanent magnet synchronous motor under constant rotation speed and no-load operation at an initial temperature T0; E2 is obtained, wherein the E2 is a counter electromotive force line voltage value read by a frequency converter under the constant rotating speed and the constant load operation of the permanent magnet synchronous motor at the initial temperature T0; Reading E3 by using a frequency converter, wherein E3 is a counter electromotive force line voltage value read by the frequency converter under the constant rotating speed and the constant load operation of the permanent magnet synchronous motor at the current temperature T1, and T1 is smaller than the demagnetizing temperature of magnetic steel of the permanent magnet synchronous motor; and calculating the current temperature T1 of the rotor of the permanent magnet synchronous motor by using the E0, the E2 and the E3 according to a preset formula.
2. The method for measuring and calculating the rotor temperature of the permanent magnet synchronous motor according to claim 1, wherein the preset formula comprises a difference calculation term, and the difference calculation term represents a difference between the E3 and the E2.
3. The method for measuring and calculating the rotor temperature of the permanent magnet synchronous motor according to claim 2, wherein the preset formula comprises a ratio calculation term, and the ratio calculation term represents the ratio of the difference value to the E0.
4. A method for measuring and calculating the rotor temperature of a permanent magnet synchronous motor according to any one of claims 1 to 3, wherein the obtaining E2 specifically includes: And at the initial temperature T0, applying the constant load to the permanent magnet synchronous motor within a preset time period, and reading the E2 by using the frequency converter at the constant rotating speed.
5. A method for measuring and calculating the rotor temperature of a permanent magnet synchronous motor in real time according to any one of claims 1 to 3, wherein the method further comprises: and acquiring a constant error value delta E of the permanent magnet synchronous motor, wherein the constant error value delta E is an error for reading a counter electromotive force line voltage value of the permanent magnet synchronous motor by using the frequency converter.
6. A method for measuring and calculating the rotor temperature of a permanent magnet synchronous motor according to any one of claims 1 to 3, wherein the obtaining E0 specifically includes: And E0 is obtained by a reverse dragging method.
7. A method for measuring and calculating the rotor temperature of a permanent magnet synchronous motor according to any one of claims 1 to 3, wherein the predetermined formula is Wherein the method comprises the steps of Is the temperature coefficient of the magnetic steel of the permanent magnet synchronous motor.
8. The utility model provides a permanent magnet synchronous motor rotor temperature real-time measuring and calculating device which characterized in that includes: the first acquisition unit is used for acquiring E0, wherein E0 is a real counter electromotive force line voltage value of the permanent magnet synchronous motor under constant rotation speed and no-load operation at an initial temperature T0; The second acquisition unit is used for acquiring E2, wherein E2 is a counter electromotive force line voltage value of the permanent magnet synchronous motor, which is read by the frequency converter under the constant rotating speed and the constant load operation of the permanent magnet synchronous motor at the initial temperature T0; the first reading unit is used for reading E3 by using a frequency converter, wherein E3 is the back electromotive force line voltage value of the permanent magnet synchronous motor read by the frequency converter under the constant rotating speed and the constant load operation of the permanent magnet synchronous motor at the current temperature T1, and T1 is smaller than the demagnetizing temperature of magnetic steel of the permanent magnet synchronous motor; and the formula calculation unit is used for calculating the current temperature T1 of the rotor of the permanent magnet synchronous motor by using the E0, the E2 and the E3 according to a preset formula.
9. A computer device, comprising: the CPU, the memory, the input/output interface and the power supply; The memory is a short-term memory or a persistent memory; The central processor is configured to communicate with the memory and to execute instruction operations in the memory to perform the method of any of claims 1 to 7.
10. A computer readable storage medium comprising instructions which, when run on a computer, cause the computer to perform the method of any of claims 1 to 7.

Description

Real-time measuring and calculating method for rotor temperature of permanent magnet synchronous motor and related equipment Technical Field The embodiment of the application relates to the field of motors, in particular to a method for measuring and calculating the temperature of a rotor of a permanent magnet synchronous motor in real time and related equipment. Background Compared with an asynchronous permanent magnet synchronous motor, the permanent magnet synchronous motor has the characteristics of high power density, high efficiency, energy conservation and the like. With implementation of new energy consumption standard of the permanent magnet synchronous motor and setting of a double-carbon target, the application breadth and depth of the permanent magnet synchronous motor in various fields of industry are accelerated and improved. However, the performance of the magnet steel of the permanent magnet synchronous motor changes along with the change of temperature, which greatly influences the output performance of the permanent magnet synchronous motor. When the temperature of the permanent magnet synchronous motor reaches a demagnetizing temperature point of a magnetic steel brand, the magnetic steel is subjected to irreversible demagnetization, so that real-time monitoring of the temperature of a rotor of the permanent magnet synchronous motor is necessary in industrial application. Disclosure of Invention The embodiment of the application provides a method and related equipment for measuring and calculating the temperature of a rotor of a permanent magnet synchronous motor in real time, which are used for improving the accuracy of measuring and calculating the temperature of the rotor of the permanent magnet synchronous motor in real time. A first aspect of an embodiment of the present application provides a method for measuring and calculating a rotor temperature of a permanent magnet synchronous motor in real time, including: Acquiring E0, wherein E0 is the real counter electromotive force line voltage value of the permanent magnet synchronous motor under constant rotation speed and no-load operation at the initial temperature T0; e2, E2 is obtained and is the back electromotive force line voltage value read by the frequency converter under the constant rotating speed and the constant load operation of the permanent magnet synchronous motor at the initial temperature T0; reading E3 by using a frequency converter, wherein E3 is the back electromotive force line voltage value read by the frequency converter under the constant rotating speed and constant load operation of the permanent magnet synchronous motor at the current temperature T1, and T1 is smaller than the demagnetizing temperature of the magnetic steel of the permanent magnet synchronous motor; According to a preset formula, the current temperature T1 of the rotor of the permanent magnet synchronous motor is calculated by using E0, E2 and E3. In an implementation manner of the first aspect of the embodiment of the present application, the preset formula includes a difference calculation term, where the difference calculation term represents a difference between E3 and E2. In an implementation manner of the first aspect of the embodiment of the present application, the preset formula includes a ratio calculation term, where the ratio calculation term represents a ratio of the difference value to E0. In an implementation manner of the first aspect of the embodiment of the present application, acquiring E2 specifically includes: at the initial temperature T0, a constant load is applied to the permanent magnet synchronous motor within a preset time period, and E2 is read by a frequency converter at a constant rotating speed. In an implementation manner of the first aspect of the embodiment of the present application, the method further includes: And acquiring a constant error value delta E of the permanent magnet synchronous motor, wherein the constant error value delta E is an error for reading a counter electromotive force line voltage value of the permanent magnet synchronous motor by using a frequency converter. That is, a constant error value Δe is obtained, where the constant error value Δe is an error between a counter electromotive force line voltage value of the permanent magnet synchronous motor and a counter electromotive force line voltage of the real permanent magnet synchronous motor, which is obtained by using a frequency converter when the permanent magnet synchronous motor is idle or under constant rotation speed and constant load. In an implementation manner of the first aspect of the embodiment of the present application, obtaining E0 specifically includes: e0 is obtained by using a reverse dragging method. In an implementation manner of the first aspect of the embodiment of the present application, the preset formula is Wherein the method comprises the steps ofIs the temperature coefficient of the magnetic steel of the pe