Motor starting control method and device, medium, motor controller and program product
By adopting a specific acceleration control strategy when starting the motor, the problem of failure of permanent magnet synchronous motor in low temperature environment is solved, and the stable operation and high reliability of the motor under low temperature conditions is achieved.
Patent Information
- Application Number
- CN202411936581.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-26
- Publication Date
- 2025-05-06
AI Technical Summary
The permanent magnet synchronous motor fails to start in a low temperature environment, resulting in the use of the equipment being affected and may cause economic losses.
When the motor starts, if the ambient temperature is lower than the preset temperature, after switching the closed-loop control with open-loop control, the motor is controlled to run at the first preset acceleration, grinding out the ice of the bearing and the waterproof ring, generating heat, increasing the gap, and reducing resistance; then the acceleration increases linearly until the second preset acceleration is reached and maintained to the maximum speed.
It effectively avoids the problem of motor start-up failure in low-temperature environments, ensures that the motor operates stably under low-temperature conditions, improves reliability and versatility, and reduces costs.
Smart Images
Figure CN119945202A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of control, and in particular to a motor starting control method, device, medium, motor controller and program product. Specifically, it relates to a motor starting control method, device, computer-readable storage medium, motor controller and computer program product. Background Art
[0002] At present, permanent magnet synchronous motors are used in many fields, and many of them are used in low temperature environments, especially in Heilongjiang, Inner Mongolia and other regions, where the temperature can even reach -40°C. In low temperature environments, the lubricating oil condenses and the waterproof ring shrinks, increasing the resistance to the motor's rotation and causing the motor to fail to start. This not only affects the use of the equipment, but can even cause significant economic losses. Summary of the invention
[0003] The main purpose of the present invention is to overcome the defects of the above-mentioned related technologies and provide a motor starting control method, device, medium, motor controller and program product to solve the problem of permanent magnet synchronous motor failure to start in a low temperature environment in the related technology.
[0004] On one hand, the present invention provides a motor starting control method, comprising: when the motor starts, if the ambient temperature is lower than a preset temperature, after the open-loop control is switched to the closed-loop control, the motor is controlled to run at a first preset acceleration; after the motor is controlled to run at the first preset acceleration for a second preset time, the acceleration of the motor is controlled to increase until it reaches a second preset acceleration; when the acceleration of the motor reaches the second preset acceleration, the motor continues to be controlled to run at the second preset acceleration until the speed of the motor reaches a preset maximum speed.
[0005] Optionally, the method further includes: performing a first PI control when the open-loop control switches to the closed-loop control; and switching to a second PI control after the duration of the first PI control reaches a first preset time and the open-loop control switches to the closed-loop control successfully.
[0006] Optionally, a proportional control parameter of the first PI control is smaller than a proportional control parameter of the second PI control; and an integral control parameter of the first PI control is smaller than an integral control parameter of the second PI control.
[0007] Optionally, controlling the acceleration of the motor to increase includes: controlling the acceleration of the motor to increase linearly according to a preset slope until a second preset acceleration is reached.
[0008] On the other hand, the present invention provides a motor starting control device, comprising: a first control unit, for controlling the motor to run at a first preset acceleration after the open-loop control switches to the closed-loop control if the ambient temperature is lower than a preset temperature when the motor starts; a second control unit, for controlling the acceleration of the motor to increase after the first control unit controls the motor to run at the first preset acceleration for a second preset time until a second preset acceleration is reached; and a third control unit, for continuing to control the motor to run at the second preset acceleration when the acceleration of the motor reaches the second preset acceleration until the speed of the motor reaches a preset maximum speed.
[0009] Optionally, it also includes: a PI control unit, which is used to perform a first PI control when the open-loop control switches to the closed-loop control; and switch to a second PI control after the duration of the first PI control reaches a first preset time and the open-loop control switches to the closed-loop control successfully.
[0010] Optionally, a proportional control parameter of the first PI control is smaller than a proportional control parameter of the second PI control; and an integral control parameter of the first PI control is smaller than an integral control parameter of the second PI control.
[0011] Optionally, the second control unit controls the acceleration of the motor to increase, including: controlling the acceleration of the motor to increase linearly according to a preset slope until a second preset acceleration is reached.
[0012] Another aspect of the present invention provides a storage medium having a computer program stored thereon, wherein the program implements the steps of any of the aforementioned methods when executed by a processor.
[0013] Another aspect of the present invention provides a motor controller, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the aforementioned methods when executing the program.
[0014] In another aspect, the present invention provides a motor controller, comprising any of the above-mentioned motor starting control devices.
[0015] In yet another aspect, the present invention provides a computer program product, comprising a computer program, wherein when the computer program is executed by a processor, the steps of any of the aforementioned methods are implemented.
[0016] According to the technical solution of the present invention, when the motor is in a low-temperature environment, when the motor is started at a low temperature, after the open-loop control is switched to the closed-loop control, the motor is first controlled to accelerate for a certain period of time at a lower acceleration to grind off the ice on the bearings and the waterproof rings, generate heat, increase the gap between the bearings and the waterproof rings, and reduce resistance; then the acceleration is controlled to increase linearly until it reaches the set value and no longer changes, thereby avoiding the increase in resistance to bearing rotation caused by condensation of lubricating fluid at the motor bearings and contraction of the waterproof rings in a low-temperature environment, which results in the motor current continuing to increase when the open-loop is switched to the closed-loop, triggering shutdown protection and starting failure. This method has high reliability and versatility.
[0017] According to the technical solution of the present invention, at the moment when the motor open-loop control switches to closed-loop control, PI control is performed according to the preset time to ensure that the motor open-loop switches to closed-loop smoothly and that the motor runs stably after the open-loop switches to closed-loop, thereby preventing the motor from shaking and causing closed-loop switching failure.
[0018] According to the technical solution of the present invention, in a low temperature environment (eg -40°C), the motor is started at low acceleration during startup, and a suitable PI duration of the instantaneous observer after the open-loop switching to the closed-loop is set, thereby solving the startup failure problem.
[0019] The technical solution of the present invention has high reliability, wide applicability and saves costs.
[0020] 1. It can solve the problem of open-loop and closed-loop failure of permanent magnet synchronous motors during low-temperature starting.
[0021] 2. It can solve the problem of permanent magnet synchronous motor failure in open loop and closed loop during low temperature starting, excessive winding current, and motor shutdown protection. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:
[0023] Figure 1 is a method schematic diagram of an embodiment of a motor starting control method provided by the present invention;
[0024] Figure 2 is a method schematic diagram of a specific embodiment of the motor starting control method provided by the present invention;
[0025] Figure 3 It is a structural block diagram of an embodiment of the motor starting control device provided by the present invention. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.
[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.
[0028] The methods for low-temperature motor starting in related technologies include: 1. Solving the starting problem from the hardware aspect, adjusting the starting voltage through the boost circuit, and adding jitter control before starting to reduce the resistance of lubricating oil adhesion, which increases the cost; 2. After entering the low-temperature starting mode, increase the starting current of the motor and run it for a period of time to reduce the resistance of the motor rotation. After running for a certain period of time, restart the motor at a normal speed. In a relatively harsh low-temperature environment, this method is likely to cause excessive current, trigger motor protection, and easily damage the motor.
[0029] The present invention provides a motor low temperature starting control method. The method can be implemented in a motor controller. The motor controller is mainly composed of a current real-time acquisition module, a voltage real-time acquisition module, a temperature acquisition module, a main control logic module and a power switch module, wherein the main control logic module is divided into three main parts: a main control logic module identification function area, a main control logic module shutdown function area and a main control logic module startup function area.
[0030] Figure 1 It is a method schematic diagram of an embodiment of the motor starting control method provided by the present invention.
[0031] like Figure 1 As shown, according to one embodiment of the present invention, the motor start control method at least includes step S110, step S120 and step S130.
[0032] Step S110, when the motor is started, if the ambient temperature is lower than a preset temperature, the motor is controlled to run at a first preset acceleration after the open-loop control is switched to the closed-loop control.
[0033] Specifically, when the motor is started, it is detected whether the ambient temperature of the environment where the motor is located is lower than a preset temperature, for example, by using a temperature detection module to detect whether the ambient temperature of the environment where the motor is located is lower than a preset temperature. If the ambient temperature of the environment where the motor is located is not lower than the preset temperature, it is considered that the motor is at room temperature, and the motor is started and operated according to a normal scheme. If the ambient temperature of the environment where the motor is located is lower than the preset temperature, it means that the motor is started in a low temperature environment, and the preset low temperature protection needs to be executed.
[0034] Preferably, when the motor is started, a first PI control is performed when the open-loop control is switched to closed-loop control; after the duration of the first PI control reaches a first preset time and the open-loop control is successfully switched to the closed-loop control, the control is switched to the second PI control; after the open-loop control is switched to the closed-loop control, the motor is controlled to run at a first preset acceleration.
[0035] Specifically, when the motor starts, it first performs open-loop starting. When the open-loop control switches to closed-loop control (i.e., the moment when the open-loop switches to the closed-loop), the first PI control is performed (the observer detects the rotor position and speed to perform the first PI control) and lasts for a first preset time t1. This time ensures that the motor's open-loop switching to closed-loop is relatively smooth, and prevents the motor from shaking and causing closed-loop switching failure.
[0036] PI control is to control based on the difference between the target value and the detected value. The control parameters of PI control can be obtained from experience. The target value can be the current at a given motor speed; the detected value can be the current at the current motor speed. PI control is a controller with proportional-integral control. It is an algorithm that controls based on the difference e(t) between the target value and the detected value. P is proportional control and I is integral control. The formula is as follows: The first part of the formula is proportional control, the second part is integral control, u(t) is the output of the control algorithm, by changing K P and K I Regulation control law, K P It will amplify the error signal e(t), making the system more sensitive. I The output will be adjusted according to the integral of the error signal e(t) in order to eliminate the error. The control parameter K of the first PI control P and K I When the open loop is switched to the closed loop, these two parameters will be too large, which will cause current oscillation and easy failure of the open loop switching to the closed loop. These two control parameters are determined by continuous debugging in actual tests.
[0037] After the first PI control is performed for the first preset time and the open-loop control is successfully switched to the closed-loop control, the second PI control is switched (the observer detects the rotor position and speed to perform the second PI control), and the motor is controlled to run at the first preset acceleration. After the first PI control (the observer detects the rotor position and speed to perform the first PI control) lasts for the first preset time t1, the second PI control is switched (the observer detects the rotor position and speed to perform the second PI control), and the motor is controlled to run at the first preset acceleration a1. The proportional control parameter of the second PI control is greater than the proportional control parameter of the first PI control. The integral control parameter of the second PI control is greater than the integral control parameter of the first PI control.
[0038] The first PI control takes effect at the moment of cutting the open loop from the closed loop, and the PI parameters are small and the duration is short. At the moment of cutting the closed loop, the output current will decrease, the current will oscillate violently, and the output current will be non-sinusoidal, which may easily lead to failure of cutting the open loop from the closed loop, and the current will increase rapidly, triggering the protection or burning the motor. Therefore, the PI control 1 parameter is small to ensure that the current is closer to the sine wave and there is no violent oscillation when the open loop is cut from the closed loop. The second PI control takes effect after the open loop is successfully cut from the closed loop. At this time, the current amplitude and frequency gradually increase, so the PI control parameters need to be increased to speed up the current response and adapt to load fluctuations.
[0039] Step S120, after controlling the motor to run at the first preset acceleration for a second preset time, controlling the acceleration of the motor to increase until reaching a second preset acceleration.
[0040] Specifically, after the motor enters closed-loop control, the acceleration is the first preset acceleration a1. When the duration is ≤ t2, the acceleration remains unchanged at the first preset acceleration a1. The purpose is to grind off the ice on the bearing and the waterproof ring, generate heat, increase the gap between the bearing and the waterproof ring, and reduce resistance. When the motor rotor maintains the a1 acceleration, the motor rotor speed increases slowly, and there will be a relatively long time for friction with the waterproof ring, grinding off the ice attached to the rotor bearing, generating heat to expand the waterproof ring, and reducing the resistance to the motor rotation.
[0041] When the duration of the motor running at the first preset acceleration a1 is greater than the second preset time t2, the acceleration starts to increase until the acceleration reaches the second preset acceleration a2. Specifically, the acceleration of the motor can be controlled to increase linearly according to the preset slope k.
[0042] Step S130: When the acceleration of the motor reaches a second preset acceleration, continue to control the motor to increase its speed at the second preset acceleration until the rotation speed of the motor reaches a preset maximum rotation speed.
[0043] Specifically, when the duration of the motor running at the first preset acceleration a1 is greater than the second preset time t2, the acceleration begins to increase linearly with a slope of k until the acceleration reaches the second preset acceleration a2, and the acceleration remains at a2 until the speed reaches the maximum speed, that is, the acceleration a=k*t+a1, until the set value a2 is reached.
[0044] In low temperature environment, for example, -40℃, the lubricating fluid in the motor bearing condenses and the waterproof seal shrinks, which increases the rotation resistance of the motor bearing. In the closed loop state, when the motor acceleration command is still the acceleration command at normal temperature, the motor bearing rotation cannot keep up with the command, and the motor winding current will continue to increase, eventually causing the motor to shut down for protection or even damage the motor. Therefore, the motor acceleration after the closed loop is a1, and when the duration is ≤t2, the acceleration remains unchanged at a1, the purpose of which is to grind off the ice between the bearing and the waterproof ring, generate heat, increase the gap between the bearing and the waterproof ring, and reduce resistance; when the acceleration a1 duration is >t2, the acceleration begins to increase linearly with a slope of k until the acceleration reaches the set value a2, and the acceleration remains at a2 until the speed reaches the highest. During this process, the motor speed gradually increases, and the time from standstill to the highest speed of the motor startup is t3.
[0045] According to the above-mentioned embodiments of the present invention, it is possible to avoid the increase in resistance to bearing rotation caused by condensation of lubricating fluid in the motor bearing and contraction of the waterproof ring in a low temperature environment, which leads to continuous increase in current when the motor switches from open loop to closed loop, triggering shutdown protection and starting failure. This method has high reliability and versatility.
[0046] In order to clearly illustrate the technical solution of the present invention, the execution process of the motor starting control method provided by the present invention is described below with reference to a specific embodiment.
[0047] Figure 2 FIG. 1 is a schematic diagram of a specific embodiment of the motor starting control method provided by the present invention. Figure 3As shown, when the motor is started, the temperature detection module is used to detect whether the ambient temperature is lower than the preset temperature T1. If the ambient temperature is higher than the preset temperature T1, it is considered that the motor is at room temperature, and the motor starts and runs according to the normal plan. If the ambient temperature is lower than the preset temperature T1, it is considered that the motor is in a low temperature environment, and the motor runs according to the starting plan in the low temperature environment. The motor starts in a low temperature environment and first performs open-loop starting. At the moment of open-loop switching, the observer detects the rotor position and speed to perform PI control 1 (first PI control) for a duration of t1. This time ensures that the motor's open-loop switching is relatively smooth to prevent motor jitter from causing closed-loop switching failure. After t1, it switches to the observer to detect the rotor position and speed for PI control 2 (second PI control). The acceleration of the motor after the closed loop is a1. When the duration is ≤t2, the acceleration remains unchanged at a1. The purpose is to grind off the ice on the bearing and the waterproof ring, generate heat, increase the gap between the bearing and the waterproof ring, and reduce resistance. When the acceleration a1 duration is >t2, the acceleration begins to increase linearly with a slope of k, that is, acceleration a=k*t+a1, until the acceleration reaches the set value a2. The acceleration remains at a2 until the speed reaches the maximum. During this process, the motor speed gradually increases, and the time for the motor to start from rest to the maximum speed is t3.
[0048] The present invention also provides a motor low temperature starting control device. The device can be implemented in a motor controller. The motor controller is mainly composed of a current real-time acquisition module, a voltage real-time acquisition module, a temperature acquisition module, a main control logic module and a power switch module, wherein the main control logic module is divided into three main parts: a main control logic module identification function area, a main control logic module shutdown function area and a main control logic module startup function area.
[0049] Figure 3 FIG. 1 is a structural block diagram of an embodiment of the motor starting control device provided by the present invention. Figure 3 As shown, the motor starting control device 100 includes: a first control unit 110 , a second control unit 120 and a third control unit 130 .
[0050] The first control unit 110 is used to control the motor to run at a first preset acceleration after the open-loop control switches to the closed-loop control when the motor is started if the ambient temperature is lower than a preset temperature.
[0051] Specifically, when the motor is started, it is detected whether the ambient temperature of the environment where the motor is located is lower than a preset temperature, for example, by using a temperature detection module to detect whether the ambient temperature of the environment where the motor is located is lower than a preset temperature. If the ambient temperature of the environment where the motor is located is not lower than the preset temperature, it is considered that the motor is at room temperature, and the motor is started and operated according to a normal scheme. If the ambient temperature of the environment where the motor is located is lower than the preset temperature, it means that the motor is started in a low temperature environment, and the preset low temperature protection needs to be executed.
[0052] Preferably, the device 100 also includes: a PI control unit, which is used to perform a first PI control when the motor is started and when the open-loop control is switched to the closed-loop control; switch to a second PI control after the duration of the first PI control reaches a first preset time, and after the open-loop control is switched to the closed-loop control, control the motor to run at a first preset acceleration.
[0053] Specifically, when the motor starts, it first performs open-loop starting. When the open-loop control switches to closed-loop control (i.e., the moment when the open-loop switches to the closed-loop), the first PI control is performed (the observer detects the rotor position and speed to perform the first PI control) and lasts for a first preset time t1. This time ensures that the motor's open-loop switching to closed-loop is relatively smooth, and prevents the motor from shaking and causing closed-loop switching failure.
[0054] PI control is to control based on the difference between the target value and the detected value. The control parameters of PI control can be obtained from experience. The target value can be the current at a given motor speed; the detected value can be the current at the current motor speed. PI control is a controller with proportional-integral control. It is an algorithm that controls based on the difference e(t) between the target value and the detected value. P is proportional control and I is integral control. The formula is as follows: The first part of the formula is proportional control, the second part is integral control, u(t) is the output of the control algorithm, by changing K P and K I Regulation control law, K P It will amplify the error signal e(t), making the system more sensitive. I The output will be adjusted according to the integral of the error signal e(t) in order to eliminate the error. The control parameter K of the first PI control P and K I When the open loop is switched to the closed loop, these two parameters will be too large, which will cause current oscillation and easy failure of the open loop switching to the closed loop. These two control parameters are determined by continuous debugging in actual tests.
[0055] After the first PI control is performed for a first preset time, the second PI control is switched to (the observer detects the rotor position and speed to perform the second PI control), and the motor is controlled to run at a first preset acceleration. After the first PI control (the observer detects the rotor position and speed to perform the first PI control) lasts for a first preset time t1, the second PI control is switched to (the observer detects the rotor position and speed to perform the second PI control), and the motor is controlled to run at a first preset acceleration a1. The proportional control parameter of the second PI control is greater than the proportional control parameter of the first PI control. The integral control parameter of the second PI control is greater than the integral control parameter of the first PI control.
[0056] The first PI control takes effect at the moment of cutting the open loop from the closed loop, and the PI parameters are small and the duration is short. At the moment of cutting the closed loop, the output current will decrease, the current will oscillate violently, and the output current will be non-sinusoidal, which may easily lead to failure of cutting the open loop from the closed loop, and the current will increase rapidly, triggering the protection or burning the motor. Therefore, the PI control 1 parameter is small to ensure that the current is closer to the sine wave and there is no violent oscillation when the open loop is cut from the closed loop. The second PI control takes effect after the open loop is successfully cut from the closed loop. At this time, the current amplitude and frequency gradually increase, so the PI control parameters need to be increased to speed up the current response and adapt to load fluctuations.
[0057] The second control unit 120 is used to control the acceleration of the motor to increase until it reaches a second preset acceleration after the first control unit controls the motor to run at the first preset acceleration for a second preset time.
[0058] Specifically, after the motor enters closed-loop control, the acceleration is the first preset acceleration a1. When the duration is ≤ t2, the acceleration remains unchanged at the first preset acceleration a1. The purpose is to grind off the ice on the bearing and the waterproof ring, generate heat, increase the gap between the bearing and the waterproof ring, and reduce resistance. When the motor rotor maintains the a1 acceleration, the motor rotor speed increases slowly, and there will be a relatively long time for friction with the waterproof ring, grinding off the ice attached to the rotor bearing, generating heat to expand the waterproof ring, and reducing the resistance to the motor rotation.
[0059] When the duration of the motor running at the first preset acceleration a1 is greater than the second preset time t2, the acceleration starts to increase until the acceleration reaches the second preset acceleration a2. Specifically, the acceleration of the motor can be controlled to increase linearly according to the preset slope k.
[0060] The third control unit 130 is used for, when the acceleration of the motor reaches a second preset acceleration, continuing to control the motor to increase its speed at the second preset acceleration until the rotation speed of the motor reaches a preset maximum rotation speed.
[0061] Specifically, when the duration of the motor running at the first preset acceleration a1 is greater than the second preset time t2, the acceleration begins to increase linearly with a slope of k until the acceleration reaches the second preset acceleration a2, and the acceleration remains at a2 until the speed reaches the maximum speed, that is, the acceleration a=k*t+a1, until the set value a2 is reached.
[0062] In a low temperature environment, such as -40℃, the lubricating fluid in the motor bearing condenses and the waterproof seal shrinks, which increases the rotation resistance of the motor bearing. In the closed loop state, when the motor acceleration command is still the acceleration command at room temperature, the motor bearing rotation cannot keep up with the command, and the motor winding current will continue to increase, eventually causing the motor to shut down for protection or even damage the motor. Therefore, the motor acceleration after the closed loop is a1, and when the duration is ≤t2, the acceleration remains unchanged at a1. The purpose is to grind off the ice on the bearing and the waterproof ring, generate heat, increase the gap between the bearing and the waterproof ring, and reduce resistance; when the acceleration a1 duration is >t2, the acceleration begins to increase linearly with a slope of k until the acceleration reaches the set value a2. The acceleration remains at a2 until the speed reaches the highest. During this process, the motor speed gradually increases, and the time from standstill to the highest speed of the motor startup is t3.
[0063] According to the above-mentioned embodiments of the present invention, it is possible to avoid the increase in resistance to bearing rotation caused by condensation of lubricating fluid in the motor bearing and contraction of the waterproof ring in a low temperature environment, which leads to continuous increase in current when the motor switches from open loop to closed loop, triggering shutdown protection and starting failure. This method has high reliability and versatility.
[0064] The present invention also provides a storage medium corresponding to the motor starting control method, on which a computer program is stored, and when the program is executed by a processor, the steps of any of the above methods are implemented.
[0065] The present invention also provides a motor controller corresponding to the motor starting control method, comprising a processor, a memory, and a computer program stored in the memory and executable on the processor, wherein the processor implements the steps of any of the aforementioned methods when executing the program.
[0066] The present invention also provides a motor controller corresponding to the motor starting control device, comprising any of the aforementioned motor starting control devices.
[0067] The present invention also provides a computer program product corresponding to the motor start-up control method, comprising a computer program, and when the computer program is executed by a processor, the steps of any of the aforementioned methods are implemented.
[0068] Based on this, the solution provided by the present invention is that when the motor is in a low-temperature environment, when the motor is started at low temperature, after the open-loop control is switched to the closed-loop control, the motor is first controlled to accelerate for a certain period of time at a lower acceleration to grind off the ice on the bearings and the waterproof rings, generate heat, increase the gap between the bearings and the waterproof rings, and reduce resistance; then the acceleration is controlled to increase linearly until it reaches the set value and no longer changes, thereby avoiding the increase in resistance of the bearings during rotation due to condensation of the lubricating fluid at the motor bearings and contraction of the waterproof rings in a low-temperature environment, which causes the current of the motor to continue to increase when the open-loop is switched to the closed-loop, triggering shutdown protection and starting failure. This method has high reliability and versatility.
[0069] The solution provided by the present invention performs PI control according to a preset time at the moment when the motor open-loop control switches to closed-loop control, to ensure that the motor open-loop switches to closed-loop smoothly, and that the motor runs stably after the open-loop switches to closed-loop, to prevent motor jitter from causing closed-loop switching failure.
[0070] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored as one or more instructions or codes on a computer-readable medium or transmitted via a computer-readable medium. Other examples and implementations are within the scope and spirit of the present invention and the appended claims. For example, due to the nature of software, the functions described above may be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these. In addition, each functional unit may be integrated into a processing unit, each unit may exist physically separately, or two or more units may be integrated into one unit.
[0071] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.
[0072] The units described as separate components may or may not be physically separated, and the components of the control device may or may not be physical units, that is, they may be located in one place or distributed in multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.
[0073] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the relevant technology or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, disk or optical disk and other media that can store program codes.
[0074] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.
Claims
1. A motor starting control method, characterized in that: include: When the motor is started, if the ambient temperature is lower than a preset temperature, the motor is controlled to run at a first preset acceleration after the open-loop control is switched to the closed-loop control; After controlling the motor to run at the first preset acceleration for a second preset time, controlling the acceleration of the motor to increase until reaching a second preset acceleration; When the acceleration of the motor reaches a second preset acceleration, the motor is continuously controlled to increase speed at the second preset acceleration until the rotation speed of the motor reaches a preset maximum rotation speed.
2. The method according to claim 1, characterized in that Also includes: When the open-loop control switches to the closed-loop control, the first PI control is performed; after the duration of the first PI control reaches a first preset time and the open-loop control switches to the closed-loop control successfully, the control is switched to the second PI control.
3. The method according to claim 2, characterized in that The proportional control parameter of the first PI control is smaller than the proportional control parameter of the second PI control; the integral control parameter of the first PI control is smaller than the integral control parameter of the second PI control.
4. The method according to any one of claims 1 to 3, characterized in that: Controlling the acceleration of the motor to increase, comprising: The acceleration of the motor is controlled to increase linearly according to a preset slope until a second preset acceleration is reached.
5. A motor starting control device, characterized in that: include: A first control unit is used to control the motor to run at a first preset acceleration after the open-loop control switches to the closed-loop control when the motor is started if the ambient temperature is lower than a preset temperature; a second control unit, configured to control the acceleration of the motor to increase until reaching a second preset acceleration after the first control unit controls the motor to run at the first preset acceleration for a second preset time; The third control unit is used for, when the acceleration of the motor reaches a second preset acceleration, continuing to control the motor to increase its speed at the second preset acceleration until the rotation speed of the motor reaches a preset maximum rotation speed.
6. The device according to claim 5, characterized in that Also includes: The PI control unit is used to perform a first PI control when the open-loop control switches to the closed-loop control; and switch to a second PI control after the duration of the first PI control reaches a first preset time and the open-loop control switches to the closed-loop control successfully.
7. The device according to claim 6, characterized in that The proportional control parameter of the first PI control is smaller than the proportional control parameter of the second PI control; the integral control parameter of the first PI control is smaller than the integral control parameter of the second PI control.
8. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the program is executed by a processor, the steps of any method described in claims 1-4 are implemented.
9. A motor controller, characterized in that: The invention comprises a processor, a memory and a computer program stored in the memory and executable on the processor, wherein when the processor executes the program, the steps of the method described in any one of claims 1 to 4 are implemented, or the invention comprises a motor starting control device described in any one of claims 5 to 7.
10. A computer program product, characterized in that The invention comprises a computer program, which implements the steps of the method according to any one of claims 1 to 4 when being executed by a processor.