An ultra-high frequency carrier high-speed industrial motor drive control method and system

Abstract

This invention discloses an ultra-high frequency carrier high-speed industrial motor drive control method and system, relating to the field of industrial motor drive control technology, including the following steps: S1: Obtain the instantaneous power fluctuation of the motor, obtain the vibration frequency of the motor spindle, obtain the load information value through the instantaneous power fluctuation and the vibration frequency of the motor spindle, obtain the instruction speed and instruction feed rate in the CNC system machining instructions, obtain the process quality value through the instruction speed and instruction feed rate, obtain the maximum allowable junction temperature and the current junction temperature of the power device, and obtain the temperature rise value through the maximum allowable junction temperature and the current junction temperature of the power device; thereby facilitating a more accurate judgment of the current grinding state, and further facilitating the subsequent adjustment of a more suitable carrier frequency based on the current grinding state, and further facilitating the automatic decision-making to switch the carrier frequency of the grinding motor based on the real-time grinding conditions, thereby improving the surface finish of the workpiece while reducing switching heating losses.

Description

Technical Field

[0001] This invention relates to the field of industrial motor drive control technology, specifically to an ultra-high frequency carrier high-speed industrial motor drive control method and system. Background Technology

[0002] The core technology of the ultra-high frequency carrier motor lies in using a power switching frequency far higher than that of the conventional one to reconstruct the motor current waveform with an extremely fine pulse sequence, making it infinitely close to the ideal sine wave. This achieves the miniaturization of electromagnetic torque pulsation from the root, thereby driving the spindle to rotate at an almost absolute constant speed. In precision grinding scenarios, this means that the grinding wheel can contact the workpiece at an extremely stable linear speed, making each micro-cut uniform and consistent, and ultimately carving a mirror-like smooth texture on the surface of the workpiece. Grinding operations are divided into rough grinding and fine grinding. During fine grinding, the motor load is small and the grinding force is small, requiring extremely stable spindle speed and minimal current ripple. Therefore, using an ultra-high carrier frequency can greatly improve the sinusoidal nature of the current waveform and reduce torque pulsation, thereby directly improving the surface finish of the workpiece and eliminating noise. However, during rough grinding, the motor load is large, the grinding force is large, and the motor output current is large. If the ultra-high carrier frequency is maintained, the switching losses will increase dramatically, the temperature rise of the driver power devices will easily trigger overheat protection or even damage them, the system efficiency will drop significantly, and energy will be wasted seriously. Therefore, traditional fixed carrier frequency motors are not suitable for the grinding field. If the motor is set with multiple frequency levels for manual switching, this relies on the operator's experience and cannot respond to instantaneous changes in the working conditions in real time. In order to facilitate the automatic decision-making and switching of the carrier frequency of the grinding motor based on the real-time grinding conditions, thereby improving the surface finish of the workpiece while reducing switching temperature rise losses, we propose an ultra-high frequency carrier high-speed industrial motor drive control method and system. Summary of the Invention

[0003] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides an ultra-high frequency carrier high-speed industrial motor drive control method and system to solve the aforementioned problems in the prior art.

[0004] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: a method for driving and controlling a high-speed industrial motor using an ultra-high frequency carrier wave, comprising the following steps: S1: Obtain the instantaneous power fluctuation of the motor, obtain the vibration frequency of the motor spindle, obtain the load information value through the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle, obtain the instruction speed and instruction feed rate in the CNC system machining instruction, obtain the process quality value through the instruction speed and instruction feed rate, obtain the maximum allowable junction temperature value and the current junction temperature value of the power device, and obtain the temperature rise value through the maximum allowable junction temperature value and the current junction temperature value of the power device; S2: Obtain the recommended carrier frequency through the load information value, process quality value and temperature rise value, obtain the current carrier frequency, and determine whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. If carrier frequency switching is performed, then execute S3; if carrier frequency switching is not performed, then repeat S1. S3: Formulate a carrier frequency ramp plan based on the temperature rise value, recommended carrier frequency and current carrier frequency, and execute carrier frequency switching according to the spindle vibration frequency and carrier frequency ramp plan.

[0005] Preferably, in S1, the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle are obtained. The load information value is obtained by combining the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle. Specifically: S101: Set a monitoring period, obtain the instantaneous power of the motor within 10 monitoring periods, and obtain the instantaneous power fluctuation of the motor by subtracting the maximum and minimum instantaneous power of the motor within 10 monitoring periods. Set a preset threshold for the instantaneous power fluctuation of the motor, and determine whether the instantaneous power fluctuation of the motor is higher than the preset threshold. If the instantaneous power fluctuation of the motor is higher than the preset threshold, mark the instantaneous power fluctuation of the motor as 1. If the instantaneous power fluctuation of the motor is lower than or equal to the preset threshold, mark the instantaneous power fluctuation of the motor as 0. S102: Set a preset threshold for the high-frequency range of spindle vibration, obtain the vibration frequency of the motor spindle, and determine whether the vibration frequency of the motor spindle is within the preset threshold for the high-frequency range of spindle vibration. If the vibration frequency of the motor spindle is within the preset threshold for the high-frequency range of spindle vibration, mark the vibration frequency of the motor spindle as 1; if the vibration frequency of the motor spindle is not within the preset threshold for the high-frequency range of spindle vibration, mark the vibration frequency of the motor spindle as 0. S103: The load information value is obtained by weighted summation of the motor spindle vibration frequency mark and the instantaneous power fluctuation mark.

[0006] Preferably, in S1, the commanded rotational speed and commanded feed rate from the CNC system machining command are obtained, and the process quality value is obtained through the commanded rotational speed and commanded feed rate, specifically as follows: S104: Obtain the instruction speed in the CNC system machining instruction, set the instruction speed preset threshold, determine whether the instruction speed is higher than or equal to the instruction speed preset threshold. If the instruction speed is higher than or equal to the instruction speed preset threshold, mark the instruction speed as 0. If the instruction speed is lower than the instruction speed preset threshold, mark the instruction speed as 1. S105: Obtain the instruction feed rate in the CNC system machining instruction, set the instruction feed rate preset threshold, determine whether the instruction feed rate is higher than or equal to the instruction feed rate preset threshold, if the instruction feed rate is higher than or equal to the instruction feed rate preset threshold, mark the instruction feed rate as 1, if the instruction feed rate is lower than the instruction feed rate preset threshold, mark the instruction feed rate as 0. S106: The process quality value is obtained by weighted summation of the commanded feed rate flag and the commanded speed flag.

[0007] Preferably, in S1, the maximum allowable junction temperature and the current junction temperature of the power device are obtained, and the temperature rise value is obtained by using the maximum allowable junction temperature and the current junction temperature of the power device. Specifically, the maximum allowable junction temperature of the power device is obtained, the current junction temperature of the power device is obtained, and the temperature rise value is obtained by subtracting the maximum allowable junction temperature of the power device from the current junction temperature of the power device.

[0008] Preferably, in S2, the recommended carrier frequency is obtained using load information values, process quality values, and temperature rise values, specifically as follows: S201: Set a preset threshold for load information value, obtain the load information value, determine whether the load information value is higher than the preset threshold for load information value, if the load information value is higher than the preset threshold for load information value, mark the load information value as a high load information value, if the load information value is lower than or equal to the preset threshold for load information value, mark the load information value as a low load information value. S202: Set a preset threshold for process quality value, obtain the process quality value, determine whether the process quality value is higher than the preset threshold for process quality value, if the process quality value is higher than the preset threshold for process quality value, mark the process quality value as a high process quality value, if the process quality value is lower than or equal to the preset threshold for process quality value, mark the process quality value as a low process quality value; S203: Set a preset threshold for temperature rise, obtain the temperature rise value, determine whether the temperature rise value is higher than the preset threshold for temperature rise, if the temperature rise value is higher than the preset threshold for temperature rise, mark the temperature rise value as a high temperature rise value, if the temperature rise value is lower than or equal to the preset threshold for temperature rise, mark the temperature rise value as a low temperature rise value. S204: Set the coarse grinding carrier frequency and the fine grinding carrier frequency, with the coarse grinding carrier frequency being lower than the fine grinding carrier frequency. If the marking result is a high load information value, a high process quality value, or a low temperature rise value, then the coarse grinding carrier frequency is used as the recommended carrier frequency. If the marking result is a low load information value, a low process quality value, or a high temperature rise value, then the fine grinding carrier frequency is used as the recommended carrier frequency.

[0009] Preferably, in S2, it is determined whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. Specifically, the current carrier frequency is obtained, the recommended carrier frequency is obtained, and it is determined whether the current carrier frequency is a coarse-grinding carrier frequency or a fine-grinding carrier frequency. If both the current carrier frequency and the recommended carrier frequency are coarse-grinding carrier frequencies or fine-grinding carrier frequencies, then there is no need to switch the carrier frequency. If one of the current carrier frequency and the other of the recommended carrier frequency is a coarse-grinding carrier frequency and the other is a fine-grinding carrier frequency, then there is a need to switch the carrier frequency.

[0010] Preferably, in S3, a carrier frequency ramp plan is formulated using the temperature rise value, the recommended carrier frequency, and the current carrier frequency, specifically as follows: S301: Obtain the temperature rise value, set the emergency preset threshold for the temperature rise value, determine whether the temperature rise value is lower than the emergency preset threshold for the temperature rise value, if the temperature rise value is lower than the emergency preset threshold for the temperature rise value, mark it as fast switching and set the fast switching interval time, if the temperature rise value is higher than or equal to the emergency preset threshold for the temperature rise value, mark it as slow switching and set the slow switching interval time, and the fast switching interval time is less than the slow switching interval time. S302: Obtain the recommended carrier frequency, obtain the current carrier frequency, obtain the carrier frequency difference by taking the absolute value of the difference between the current carrier frequency and the recommended carrier frequency, divide the carrier frequency difference by 10 to obtain the single handover frequency, obtain the handover marking result, if the handover marking result is fast handover, then gradually switch the carrier frequency according to the fast handover interval time and the single handover frequency, if the handover marking result is slow handover, then gradually switch the carrier frequency according to the slow handover interval time and the single handover frequency.

[0011] Preferably, in S3, carrier frequency switching is performed based on the spindle vibration frequency and the carrier frequency ramp plan, specifically as follows: S303: Obtain the spindle vibration frequency, set a preset threshold for fine-tuning frequency offset, obtain the minimum vibration frequency interference by subtracting the spindle vibration frequency from the preset threshold for fine-tuning frequency offset, obtain the maximum vibration frequency interference by summing the spindle vibration frequency from the preset threshold for fine-tuning frequency offset, and obtain the interference frequency range by subtracting the minimum vibration frequency interference from the maximum vibration frequency interference. S304: Obtain 10 target carrier frequencies by summing the current carrier frequency with 1 to 10 single-switching frequencies respectively. Determine whether each of the 10 target carrier frequencies is within the interference frequency range. If none of the 10 target carrier frequencies is within the interference frequency range, then perform carrier frequency switching according to the carrier frequency ramp plan. If any of the 10 target carrier frequencies is within the interference frequency range, then mark the target carrier frequency within the interference frequency range as the resonant carrier frequency. Determine whether the resonant carrier frequency is the recommended carrier frequency. If the resonant carrier frequency is the recommended carrier frequency, then subtract the recommended carrier frequency from one single-switching frequency to obtain a new recommended carrier frequency and repeat S302. If the resonant carrier frequency is not the recommended carrier frequency, then skip the resonant carrier frequency during carrier frequency switching.

[0012] A high-speed industrial motor drive control system with ultra-high frequency carrier wave, comprising the following modules: The grinding parameter processing module acquires the instantaneous power fluctuation of the motor, the vibration frequency of the motor spindle, and obtains the load information value through the instantaneous power fluctuation and the vibration frequency of the motor spindle. It also acquires the command speed and command feed rate from the CNC system's machining instructions, obtains the process quality value through the command speed and command feed rate, acquires the maximum allowable junction temperature and the current junction temperature of the power device, and obtains the temperature rise value through the maximum allowable junction temperature and the current junction temperature of the power device. The carrier frequency switching judgment module obtains the recommended carrier frequency through the load information value, process quality value and temperature rise value, acquires the current carrier frequency, and determines whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. If carrier frequency switching is to be performed, the carrier frequency switching execution module is executed. If carrier frequency switching is not to be performed, the grinding parameter processing module is executed repeatedly. The carrier frequency switching execution module formulates a carrier frequency ramp plan based on the temperature rise value, recommended carrier frequency, and current carrier frequency, and executes carrier frequency switching according to the spindle vibration frequency and the carrier frequency ramp plan.

[0013] (III) Beneficial Effects This invention provides a method and system for driving and controlling a high-speed industrial motor using ultra-high frequency carrier waves, which has the following advantages: (1) In this scheme, the current grinding state is analyzed by combining the motor working state, CNC machine tool instructions and the temperature rise value of power devices, so as to make more accurate judgment of the current grinding state, and then make it easier to adjust the carrier frequency more appropriately according to the current grinding state, and then make it easier to automatically switch the carrier frequency of the grinding motor according to the real-time grinding conditions, thereby improving the surface finish of the workpiece while reducing the switching temperature rise loss.

[0014] (2) In this scheme, a carrier frequency ramp plan is formulated by using the temperature rise value, recommended carrier frequency and current carrier frequency, so as to facilitate the gradual switching when switching carrier frequencies, avoid the current and torque caused by a one-time direct switch to the position, which will cause grinding defects on the surface of the workpiece. It is also beneficial to avoid the risk of voltage shock or overvoltage that could damage the motor, and also beneficial to avoid the current loop oscillation caused by the instability of the control loop. At the same time, the switching rate is adjusted according to the temperature rise value, so as to facilitate the adjustment of the switching rate according to the actual temperature pressure of the power device, and avoid the power device from working at high temperature for a long time, which will affect its service life.

[0015] (3) In this scheme, the carrier frequency is switched according to the spindle vibration frequency and the carrier frequency ramp plan, so as to bypass the spindle vibration frequency when switching the carrier frequency, avoid the spindle resonance causing severe oscillation in the grinding operation, and thus help to avoid the grinding tool from oscillating and scratching the workpiece, thereby improving the safety of the grinding operation. Attached Figure Description

[0016] Figure 1 This is a flowchart of a high-speed industrial motor drive control method using ultra-high frequency carrier waves according to the present invention. Figure 2 This is a schematic diagram of the module structure of an ultra-high frequency carrier high-speed industrial motor drive control system according to the present invention. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Please see Figures 1-2 This invention provides a method for driving and controlling a high-speed industrial motor using an ultra-high frequency carrier wave, comprising the following steps: S1: Obtain the instantaneous power fluctuation of the motor, obtain the vibration frequency of the motor spindle, obtain the load information value through the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle, obtain the instruction speed and instruction feed rate in the CNC system machining instruction, obtain the process quality value through the instruction speed and instruction feed rate, obtain the maximum allowable junction temperature value and the current junction temperature value of the power device, and obtain the temperature rise value through the maximum allowable junction temperature value and the current junction temperature value of the power device; S2: Obtain the recommended carrier frequency through the load information value, process quality value and temperature rise value, obtain the current carrier frequency, and determine whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. If carrier frequency switching is performed, then execute S3; if carrier frequency switching is not performed, then repeat S1. S3: Formulate a carrier frequency ramp plan based on the temperature rise value, recommended carrier frequency and current carrier frequency, and execute carrier frequency switching according to the spindle vibration frequency and carrier frequency ramp plan.

[0019] In this embodiment, the load information value is obtained by the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle. Since the grinding resistance is high during rough grinding, the instantaneous power of the motor and the vibration frequency of the spindle will be higher, which makes it easier to judge the current grinding condition based on the actual working table of the motor. The process quality value is obtained by the command speed and command feed rate. Since the command speed and command feed rate of the CNC machine tool are higher during rough grinding, the current grinding condition can be judged by the input command of the CNC machine tool. The temperature rise value is obtained by the maximum allowable junction temperature value and the current junction temperature value of the power device. Since the resistance is high during rough grinding, the junction temperature value of the power device is higher and the temperature rise value is lower, which makes it easier to judge the current grinding condition by the temperature rise value of the power device. In this embodiment, the current grinding condition is comprehensively analyzed by combining the motor working status, CNC machine tool command and the temperature rise value of the power device, which makes it easier to judge the current grinding condition more accurately. This facilitates the subsequent adjustment of a more suitable carrier frequency based on the current grinding condition, and facilitates the automatic decision-making to switch the carrier frequency of the grinding motor based on the real-time grinding condition, thereby improving the surface finish of the workpiece while reducing the switching heating loss. In this solution, the recommended carrier frequency is obtained through load information value, process quality value and temperature rise value, so as to give the corresponding recommended carrier frequency according to the current grinding situation. This helps to avoid the grinding efficiency being reduced by low carrier frequency during fine grinding, and also helps to avoid the impact of high carrier frequency on switching temperature rise loss during rough grinding. When it is not necessary to switch the carrier frequency, the judgment is repeated, which facilitates real-time monitoring of the current grinding status and facilitates rapid and intelligent switching of carrier frequency according to changes in the grinding status. This scheme establishes a carrier frequency ramp plan based on temperature rise, recommended carrier frequency, and current carrier frequency. This facilitates gradual switching when changing carrier frequencies, avoiding direct switching that could cause current and torque issues leading to grinding defects on the workpiece surface. It also helps avoid voltage surges or overvoltage risks that could damage the motor, and prevents current loop oscillations caused by control loop instability. Furthermore, adjusting the switching rate based on the temperature rise allows for adjustments to the switching rate according to the actual temperature requirements of the power devices, preventing prolonged high-temperature operation from affecting their lifespan. The carrier frequency switching is executed based on the spindle vibration frequency and the carrier frequency ramp plan, allowing the switching frequency to bypass the spindle vibration frequency and avoid severe oscillations during grinding caused by spindle resonance. This, in turn, helps prevent the grinding tool from scratching the workpiece due to oscillations, improving the safety of the grinding operation. It is worth mentioning that the value of the preset threshold in this scheme can be obtained through weight analysis, which will not be elaborated on here.

[0020] In S1, the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle are obtained. The load information value is obtained by combining the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle. Specifically: S101: Set a monitoring period, obtain the instantaneous power of the motor within 10 monitoring periods, and obtain the instantaneous power fluctuation of the motor by subtracting the maximum and minimum instantaneous power of the motor within 10 monitoring periods. Set a preset threshold for the instantaneous power fluctuation of the motor, and determine whether the instantaneous power fluctuation of the motor is higher than the preset threshold. If the instantaneous power fluctuation of the motor is higher than the preset threshold, mark the instantaneous power fluctuation of the motor as 1. If the instantaneous power fluctuation of the motor is lower than or equal to the preset threshold, mark the instantaneous power fluctuation of the motor as 0. S102: Set a preset threshold for the high-frequency range of spindle vibration, obtain the vibration frequency of the motor spindle, and determine whether the vibration frequency of the motor spindle is within the preset threshold for the high-frequency range of spindle vibration. If the vibration frequency of the motor spindle is within the preset threshold for the high-frequency range of spindle vibration, mark the vibration frequency of the motor spindle as 1; if the vibration frequency of the motor spindle is not within the preset threshold for the high-frequency range of spindle vibration, mark the vibration frequency of the motor spindle as 0. S103: The load information value is obtained by weighted summation of the motor spindle vibration frequency mark and the instantaneous power fluctuation mark of the motor; In S1, the commanded rotational speed and feed rate from the CNC system machining command are obtained, and the process quality value is obtained through the commanded rotational speed and feed rate, specifically as follows: S104: Obtain the instruction speed in the CNC system machining instruction, set the instruction speed preset threshold, determine whether the instruction speed is higher than or equal to the instruction speed preset threshold. If the instruction speed is higher than or equal to the instruction speed preset threshold, mark the instruction speed as 0. If the instruction speed is lower than the instruction speed preset threshold, mark the instruction speed as 1. S105: Obtain the instruction feed rate in the CNC system machining instruction, set the instruction feed rate preset threshold, determine whether the instruction feed rate is higher than or equal to the instruction feed rate preset threshold, if the instruction feed rate is higher than or equal to the instruction feed rate preset threshold, mark the instruction feed rate as 1, if the instruction feed rate is lower than the instruction feed rate preset threshold, mark the instruction feed rate as 0. S106: The process quality value is obtained by weighted summing of the commanded feed rate flag and the commanded speed flag; In S1, the maximum allowable junction temperature and the current junction temperature of the power device are obtained. The temperature rise value is obtained by taking the difference between the maximum allowable junction temperature and the current junction temperature of the power device. Specifically, the maximum allowable junction temperature of the power device is obtained, the current junction temperature of the power device is obtained, and the temperature rise value is obtained by taking the difference between the maximum allowable junction temperature and the current junction temperature of the power device.

[0021] In this embodiment, the load information value is obtained by the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle. Since the grinding resistance is high during rough grinding, the instantaneous power of the motor and the vibration frequency of the spindle will be higher, which makes it easier to judge the current grinding condition based on the actual working turntable of the motor. The process quality value is obtained by the commanded speed and commanded feed rate. Since the commanded speed and commanded feed rate of the CNC machine tool are higher during rough grinding, the current grinding condition can be judged by the input command of the CNC machine tool. The temperature rise value is obtained by the maximum allowable junction temperature value of the power device and the current junction temperature value. Since the resistance is high during rough grinding, the junction temperature value of the power device is higher and the temperature rise value is lower, which makes it easier to judge the current grinding condition by the temperature rise value of the power device.

[0022] In S2, the recommended carrier frequency is obtained using load information values, process quality values, and temperature rise values, specifically: S201: Set a preset threshold for load information value, obtain the load information value, determine whether the load information value is higher than the preset threshold for load information value, if the load information value is higher than the preset threshold for load information value, mark the load information value as a high load information value, if the load information value is lower than or equal to the preset threshold for load information value, mark the load information value as a low load information value. S202: Set a preset threshold for process quality value, obtain the process quality value, determine whether the process quality value is higher than the preset threshold for process quality value, if the process quality value is higher than the preset threshold for process quality value, mark the process quality value as a high process quality value, if the process quality value is lower than or equal to the preset threshold for process quality value, mark the process quality value as a low process quality value; S203: Set a preset threshold for temperature rise, obtain the temperature rise value, determine whether the temperature rise value is higher than the preset threshold for temperature rise, if the temperature rise value is higher than the preset threshold for temperature rise, mark the temperature rise value as a high temperature rise value, if the temperature rise value is lower than or equal to the preset threshold for temperature rise, mark the temperature rise value as a low temperature rise value. S204: Set the coarse grinding carrier frequency and the fine grinding carrier frequency, with the coarse grinding carrier frequency being lower than the fine grinding carrier frequency. If the marking result is a high load information value, a high process quality value, or a low temperature rise value, then the coarse grinding carrier frequency is used as the recommended carrier frequency. If the marking result is a low load information value, a low process quality value, or a high temperature rise value, then the fine grinding carrier frequency is used as the recommended carrier frequency.

[0023] In this embodiment, the current grinding state is comprehensively analyzed by combining the motor operating status, CNC machine tool instructions, and the temperature rise value of power devices. This facilitates a more accurate judgment of the current grinding state, which in turn facilitates the subsequent adjustment of a more suitable carrier frequency based on the current grinding state. Furthermore, it facilitates the automated decision-making to switch the carrier frequency of the grinding motor based on the real-time grinding conditions, thereby improving the surface finish of the workpiece while reducing switching temperature rise losses.

[0024] In S2, the decision to perform a carrier frequency switch is made based on the recommended carrier frequency and the current carrier frequency. Specifically, the current carrier frequency is obtained, the recommended carrier frequency is obtained, and it is determined whether the current carrier frequency is a coarse-grinding carrier frequency or a fine-grinding carrier frequency. If both the current carrier frequency and the recommended carrier frequency are coarse-grinding carrier frequencies or fine-grinding carrier frequencies, then no carrier frequency switch is required. If one of the current carrier frequency and the other of the recommended carrier frequency is a coarse-grinding carrier frequency and the other is a fine-grinding carrier frequency, then a carrier frequency switch is required.

[0025] In this embodiment, the recommended carrier frequency is obtained through load information value, process quality value and temperature rise value, so as to give the corresponding recommended carrier frequency according to the current grinding situation. This helps to avoid the grinding efficiency being reduced by low carrier frequency during fine grinding, and also helps to avoid the impact of high carrier frequency on the switching temperature rise loss during rough grinding. When it is not necessary to switch the carrier frequency, the judgment is repeated, which facilitates real-time monitoring of the current grinding status, and facilitates rapid and intelligent switching of carrier frequency according to changes in the grinding status.

[0026] In S3, a carrier frequency ramp plan is formulated using the temperature rise value, the recommended carrier frequency, and the current carrier frequency, specifically as follows: S301: Obtain the temperature rise value, set the emergency preset threshold for the temperature rise value, determine whether the temperature rise value is lower than the emergency preset threshold for the temperature rise value, if the temperature rise value is lower than the emergency preset threshold for the temperature rise value, mark it as fast switching and set the fast switching interval time, if the temperature rise value is higher than or equal to the emergency preset threshold for the temperature rise value, mark it as slow switching and set the slow switching interval time, and the fast switching interval time is less than the slow switching interval time. S302: Obtain the recommended carrier frequency, obtain the current carrier frequency, obtain the carrier frequency difference by taking the absolute value of the difference between the current carrier frequency and the recommended carrier frequency, divide the carrier frequency difference by 10 to obtain the single handover frequency, obtain the handover marking result, if the handover marking result is fast handover, then gradually switch the carrier frequency according to the fast handover interval time and the single handover frequency, if the handover marking result is slow handover, then gradually switch the carrier frequency according to the slow handover interval time and the single handover frequency.

[0027] In this embodiment, a carrier frequency ramp plan is formulated by using the temperature rise value, recommended carrier frequency, and current carrier frequency. This facilitates a gradual switching when changing carrier frequencies, avoiding a one-time direct switch that could cause current and torque issues leading to grinding defects on the workpiece surface. It also helps avoid damage to the motor caused by voltage surges or overvoltage risks, and prevents current loop oscillations caused by control loop instability. Furthermore, the switching rate is adjusted based on the temperature rise value, making it easier to adjust the switching rate according to the actual temperature pressure of the power devices, thus preventing the power devices from operating at high temperatures for extended periods and affecting their service life.

[0028] In S3, carrier frequency switching is performed based on the spindle vibration frequency and carrier frequency ramp plan, specifically as follows: S303: Obtain the spindle vibration frequency, set a preset threshold for fine-tuning frequency offset, obtain the minimum vibration frequency interference by subtracting the spindle vibration frequency from the preset threshold for fine-tuning frequency offset, obtain the maximum vibration frequency interference by summing the spindle vibration frequency from the preset threshold for fine-tuning frequency offset, and obtain the interference frequency range by subtracting the minimum vibration frequency interference from the maximum vibration frequency interference. S304: Obtain 10 target carrier frequencies by summing the current carrier frequency with 1 to 10 single-switching frequencies respectively. Determine whether each of the 10 target carrier frequencies is within the interference frequency range. If none of the 10 target carrier frequencies is within the interference frequency range, then perform carrier frequency switching according to the carrier frequency ramp plan. If any of the 10 target carrier frequencies is within the interference frequency range, then mark the target carrier frequency within the interference frequency range as the resonant carrier frequency. Determine whether the resonant carrier frequency is the recommended carrier frequency. If the resonant carrier frequency is the recommended carrier frequency, then subtract the recommended carrier frequency from one single-switching frequency to obtain a new recommended carrier frequency and repeat S302. If the resonant carrier frequency is not the recommended carrier frequency, then skip the resonant carrier frequency during carrier frequency switching.

[0029] In this embodiment, the carrier frequency is switched according to the spindle vibration frequency and the carrier frequency ramp plan, which makes it easier to bypass the spindle vibration frequency when switching the carrier frequency, avoid causing spindle resonance and severe oscillation during grinding, and thus help to avoid the grinding tool from oscillating and scratching the workpiece, thereby improving the safety of grinding operations.

[0030] Please see Figures 1-2 This invention provides an ultra-high frequency carrier high-speed industrial motor drive control system, comprising the following modules: The grinding parameter processing module acquires the instantaneous power fluctuation of the motor, the vibration frequency of the motor spindle, and obtains the load information value through the instantaneous power fluctuation and the vibration frequency of the motor spindle. It also acquires the command speed and command feed rate from the CNC system's machining instructions, obtains the process quality value through the command speed and command feed rate, acquires the maximum allowable junction temperature and the current junction temperature of the power device, and obtains the temperature rise value through the maximum allowable junction temperature and the current junction temperature of the power device. The carrier frequency switching judgment module obtains the recommended carrier frequency through the load information value, process quality value and temperature rise value, acquires the current carrier frequency, and determines whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. If carrier frequency switching is to be performed, the carrier frequency switching execution module is executed. If carrier frequency switching is not to be performed, the grinding parameter processing module is executed repeatedly. The carrier frequency switching execution module formulates a carrier frequency ramp plan based on the temperature rise value, recommended carrier frequency, and current carrier frequency, and executes carrier frequency switching according to the spindle vibration frequency and the carrier frequency ramp plan.

[0031] The above embodiments can be implemented, in whole or in part, by software, hardware, firmware, or any other combination thereof. When implemented in software, the above embodiments can be implemented, in whole or in part, as a computer program product. Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution.

[0032] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0033] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application.

Claims

1. A method for driving and controlling a high-speed industrial motor using ultra-high frequency carrier waves, characterized in that, Includes the following steps: S1: Obtain the instantaneous power fluctuation of the motor, obtain the vibration frequency of the motor spindle, obtain the load information value through the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle, obtain the instruction speed and instruction feed rate in the CNC system machining instruction, obtain the process quality value through the instruction speed and instruction feed rate, obtain the maximum allowable junction temperature value and the current junction temperature value of the power device, and obtain the temperature rise value through the maximum allowable junction temperature value and the current junction temperature value of the power device; S2: Obtain the recommended carrier frequency through the load information value, process quality value and temperature rise value, obtain the current carrier frequency, and determine whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. If carrier frequency switching is performed, then execute S3; if carrier frequency switching is not performed, then repeat S1. S3: Formulate a carrier frequency ramp plan based on the temperature rise value, recommended carrier frequency and current carrier frequency, and execute carrier frequency switching according to the spindle vibration frequency and carrier frequency ramp plan.

2. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 1, characterized in that: In S1, the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle are obtained. The load information value is obtained by combining the instantaneous power fluctuation of the motor and the vibration frequency of the motor spindle. Specifically: S101: Set a monitoring period, obtain the instantaneous power of the motor within 10 monitoring periods, and obtain the instantaneous power fluctuation of the motor by subtracting the maximum and minimum instantaneous power of the motor within 10 monitoring periods. Set a preset threshold for the instantaneous power fluctuation of the motor, and determine whether the instantaneous power fluctuation of the motor is higher than the preset threshold. If the instantaneous power fluctuation of the motor is higher than the preset threshold, mark the instantaneous power fluctuation of the motor as 1. If the instantaneous power fluctuation of the motor is lower than or equal to the preset threshold, mark the instantaneous power fluctuation of the motor as 0. S102: Set a preset threshold for the high-frequency range of spindle vibration, obtain the vibration frequency of the motor spindle, and determine whether the vibration frequency of the motor spindle is within the preset threshold for the high-frequency range of spindle vibration. If the vibration frequency of the motor spindle is within the preset threshold for the high-frequency range of spindle vibration, mark the vibration frequency of the motor spindle as 1; if the vibration frequency of the motor spindle is not within the preset threshold for the high-frequency range of spindle vibration, mark the vibration frequency of the motor spindle as 0. S103: The load information value is obtained by weighted summation of the motor spindle vibration frequency mark and the instantaneous power fluctuation mark.

3. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 1, characterized in that: In S1, the commanded rotational speed and feed rate from the CNC system machining command are obtained, and the process quality value is obtained through the commanded rotational speed and feed rate, specifically as follows: S104: Obtain the instruction speed in the CNC system machining instruction, set the instruction speed preset threshold, determine whether the instruction speed is higher than or equal to the instruction speed preset threshold. If the instruction speed is higher than or equal to the instruction speed preset threshold, mark the instruction speed as 0. If the instruction speed is lower than the instruction speed preset threshold, mark the instruction speed as 1. S105: Obtain the instruction feed rate in the CNC system machining instruction, set the instruction feed rate preset threshold, determine whether the instruction feed rate is higher than or equal to the instruction feed rate preset threshold, if the instruction feed rate is higher than or equal to the instruction feed rate preset threshold, mark the instruction feed rate as 1, if the instruction feed rate is lower than the instruction feed rate preset threshold, mark the instruction feed rate as 0. S106: The process quality value is obtained by weighted summation of the commanded feed rate flag and the commanded speed flag.

4. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 1, characterized in that: In S1, the maximum allowable junction temperature and the current junction temperature of the power device are obtained. The temperature rise value is obtained by taking the difference between the maximum allowable junction temperature and the current junction temperature of the power device. Specifically, the maximum allowable junction temperature of the power device is obtained, the current junction temperature of the power device is obtained, and the temperature rise value is obtained by taking the difference between the maximum allowable junction temperature and the current junction temperature of the power device.

5. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 1, characterized in that: In S2, the recommended carrier frequency is obtained using load information values, process quality values, and temperature rise values, specifically: S201: Set a preset threshold for load information value, obtain the load information value, determine whether the load information value is higher than the preset threshold for load information value, if the load information value is higher than the preset threshold for load information value, mark the load information value as a high load information value, if the load information value is lower than or equal to the preset threshold for load information value, mark the load information value as a low load information value. S202: Set a preset threshold for process quality value, obtain the process quality value, determine whether the process quality value is higher than the preset threshold for process quality value, if the process quality value is higher than the preset threshold for process quality value, mark the process quality value as a high process quality value, if the process quality value is lower than or equal to the preset threshold for process quality value, mark the process quality value as a low process quality value; S203: Set a preset threshold for temperature rise, obtain the temperature rise value, determine whether the temperature rise value is higher than the preset threshold for temperature rise, if the temperature rise value is higher than the preset threshold for temperature rise, mark the temperature rise value as a high temperature rise value, if the temperature rise value is lower than or equal to the preset threshold for temperature rise, mark the temperature rise value as a low temperature rise value. S204: Set the coarse grinding carrier frequency and the fine grinding carrier frequency, with the coarse grinding carrier frequency being lower than the fine grinding carrier frequency. If the marking result is a high load information value, a high process quality value, or a low temperature rise value, then the coarse grinding carrier frequency is used as the recommended carrier frequency. If the marking result is a low load information value, a low process quality value, or a high temperature rise value, then the fine grinding carrier frequency is used as the recommended carrier frequency.

6. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 1, characterized in that: In S2, the decision to perform a carrier frequency switch is made based on the recommended carrier frequency and the current carrier frequency. Specifically, the current carrier frequency is obtained, the recommended carrier frequency is obtained, and it is determined whether the current carrier frequency is a coarse-grinding carrier frequency or a fine-grinding carrier frequency. If both the current carrier frequency and the recommended carrier frequency are coarse-grinding carrier frequencies or fine-grinding carrier frequencies, then no carrier frequency switch is required. If one of the current carrier frequency and the other of the recommended carrier frequency is a coarse-grinding carrier frequency and the other is a fine-grinding carrier frequency, then a carrier frequency switch is required.

7. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 1, characterized in that: In S3, a carrier frequency ramp plan is formulated using the temperature rise value, the recommended carrier frequency, and the current carrier frequency, specifically as follows: S301: Obtain the temperature rise value, set the emergency preset threshold for the temperature rise value, determine whether the temperature rise value is lower than the emergency preset threshold for the temperature rise value, if the temperature rise value is lower than the emergency preset threshold for the temperature rise value, mark it as fast switching and set the fast switching interval time, if the temperature rise value is higher than or equal to the emergency preset threshold for the temperature rise value, mark it as slow switching and set the slow switching interval time, and the fast switching interval time is less than the slow switching interval time. S302: Obtain the recommended carrier frequency, obtain the current carrier frequency, obtain the carrier frequency difference by taking the absolute value of the difference between the current carrier frequency and the recommended carrier frequency, divide the carrier frequency difference by 10 to obtain the single handover frequency, obtain the handover marking result, if the handover marking result is fast handover, then gradually switch the carrier frequency according to the fast handover interval time and the single handover frequency, if the handover marking result is slow handover, then gradually switch the carrier frequency according to the slow handover interval time and the single handover frequency.

8. The ultra-high frequency carrier high-speed industrial motor drive control method according to claim 7, characterized in that: In S3, carrier frequency switching is performed based on the spindle vibration frequency and carrier frequency ramp plan, specifically as follows: S303: Obtain the spindle vibration frequency, set a preset threshold for fine-tuning frequency offset, obtain the minimum vibration frequency interference by subtracting the spindle vibration frequency from the preset threshold for fine-tuning frequency offset, obtain the maximum vibration frequency interference by summing the spindle vibration frequency from the preset threshold for fine-tuning frequency offset, and obtain the interference frequency range by subtracting the minimum vibration frequency interference from the maximum vibration frequency interference. S304: Obtain 10 target carrier frequencies by summing the current carrier frequency with 1 to 10 single-switching frequencies respectively. Determine whether each of the 10 target carrier frequencies is within the interference frequency range. If none of the 10 target carrier frequencies is within the interference frequency range, then perform carrier frequency switching according to the carrier frequency ramp plan. If any of the 10 target carrier frequencies is within the interference frequency range, then mark the target carrier frequency within the interference frequency range as the resonant carrier frequency. Determine whether the resonant carrier frequency is the recommended carrier frequency. If the resonant carrier frequency is the recommended carrier frequency, then subtract the recommended carrier frequency from one single-switching frequency to obtain a new recommended carrier frequency and repeat S302. If the resonant carrier frequency is not the recommended carrier frequency, then skip the resonant carrier frequency during carrier frequency switching.

9. A high-speed industrial motor drive control system using ultra-high frequency carrier wave, applied to the high-speed industrial motor drive control method using ultra-high frequency carrier wave as described in any one of claims 1-8, characterized in that, Includes the following modules: The grinding parameter processing module acquires the instantaneous power fluctuation of the motor, the vibration frequency of the motor spindle, and obtains the load information value through the instantaneous power fluctuation and the vibration frequency of the motor spindle. It also acquires the command speed and command feed rate from the CNC system's machining instructions, obtains the process quality value through the command speed and command feed rate, acquires the maximum allowable junction temperature and the current junction temperature of the power device, and obtains the temperature rise value through the maximum allowable junction temperature and the current junction temperature of the power device. The carrier frequency switching judgment module obtains the recommended carrier frequency through the load information value, process quality value and temperature rise value, acquires the current carrier frequency, and determines whether to perform carrier frequency switching based on the recommended carrier frequency and the current carrier frequency. If carrier frequency switching is to be performed, the carrier frequency switching execution module is executed. If carrier frequency switching is not to be performed, the grinding parameter processing module is executed repeatedly. The carrier frequency switching execution module formulates a carrier frequency ramp plan based on the temperature rise value, recommended carrier frequency, and current carrier frequency, and executes carrier frequency switching according to the spindle vibration frequency and the carrier frequency ramp plan.

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