Motor starting method based on angle fitting

Abstract

The invention discloses a motor starting method based on angle fitting, and relates to the technical field of motor starting. According to the method, rapid and stable starting of the motor is ensured through fine angle fitting and current closed-loop control, the method is particularly suitable for the motor with a large-inertia load, the method comprises the steps of initial positioning of the motor, dragging acceleration, closed-loop operation and the like, control parameters are adjusted through feedback of a rotary transformer (rotary transformer) during debugging, and faults are monitored during starting operation. In addition, the method also considers forward and reverse rotation switching and communication fault processing under the condition of no-position operation, so that the flexibility and the reliability of the system are improved.

Description

Technical Field

[0001] The present application belongs to the technical field of motor starting, and in particular relates to a motor starting method based on angle fitting. Background Art

[0002] At present, some upper-mounted controllers have special working condition function requirements based on actual application scenarios. There is a risk that when a rotational transformer failure occurs, the mixing drum will not be able to operate, resulting in the solidification of the concrete inside the mixing drum. There is no redundant limp function.

[0003] In current mainstream sensorless control, there is a significant discrepancy between the estimated rotor angle at low speeds and the actual rotor angle. Directly starting the motor using the estimated angle can significantly affect motor stability and even cause the motor to stall. Common sensorless starting methods are primarily categorized into high-frequency injection and open-loop starting. Open-loop starting primarily utilizes voltage-to-frequency (V / F) and current-to-frequency (I / F) control methods. I / F control is an open-loop control algorithm based on V / F control. Leveraging its inherent self-stability between torque and rotor position, I / F effectively prevents current overshoot and achieves closed-loop control of the motor's operating current. However, due to its lack of ability to adjust the virtual q-axis current based on load variations, it is only suitable for short, low-speed starting procedures. It is primarily used to assist in achieving stable starting of PMSMs.

[0004] During the I / F dragging stage, the angle of current application is obtained from the target dragging speed. When this is applied to start a motor with a large inertia load, the initial state is affected by the large inertia load, causing the actual motor rotor to rotate slowly. The angle obtained from the target dragging speed deviates significantly from the actual angle, making it easy for the dragging to lose step and cause startup failure. Summary of the Invention

[0005] The purpose of this application is to provide a motor starting method based on angle fitting, which is developed for the upper controller function of the mixer truck to improve the speed and reliability of starting the motor with a large inertia load.

[0006] To achieve the above objectives, the present invention provides a motor starting method based on angle fitting, comprising:

[0007] Output the preset duty cycle to locate the initial position of the motor. During the debugging phase, use the resolver feedback angle to debug the positioning parameters. When the resolver feedback angle is consistent with the preset angle and meets the response requirements, solidify the positioning parameters.

[0008] The motor is dragged and accelerated based on the set target drag current. The drag current distribution angle is based on the fitting curve. During the debugging phase, the rotary transformer feedback angle is used to debug the drag parameters and fit the angle curve. When the rotary transformer feedback angle is consistent with the drag angle, the drag angle simulation curve is obtained and the drag parameters are solidified.

[0009] When the motor speed is detected to be higher than the set threshold for switching to the closed loop during dragging, the closed loop is switched to run, and the dragging current gradually and smoothly transitions to the speed loop output current.

[0010] The above method according to the embodiment of the present application may also have the following additional technical features:

[0011] Furthermore, when the motor starts running, fault detection is performed. If a resolver fault is detected in the memory, the motor is directly switched to positionless operation and runs at the angle and speed obtained by the observer.

[0012] Furthermore, when the motor starts running, fault detection is performed. If it is detected that there is no resolver fault in the memory, but a resolver fault is detected before running, it is directly switched to positionless operation and runs at the angle and speed obtained by the observer.

[0013] Furthermore, when the motor starts running, fault detection is performed. If it is detected that there is no resolver fault in the memory, but a resolver fault is detected during operation, the motor is first stopped and then switched to positionless operation, running at the angle and speed obtained by the observer.

[0014] Furthermore, when the motor starts running, a fault detection is performed. If it is detected that there is no resolver fault in the memory and no resolver fault is detected during operation, the motor runs at the angle and speed obtained by the resolver.

[0015] Furthermore, after the motor switches from startup operation to position-free operation, if the resolver fault recovery is detected, it still operates in position-free operation and runs at the angle and speed obtained by the observer.

[0016] Furthermore, it receives the command speed, torque limit, mode and enable from the vehicle controller;

[0017] Determine whether the motor switches forward or reverse in the position-free running state. If so, determine whether the host computer command is consistent with the actual running direction. If they are consistent, respond directly to the command speed; if not, stop the motor first and then respond to the command speed; if no forward or reverse switching occurs, respond directly to the command speed;

[0018] After responding to the command speed, determine whether there is a communication fault. If so, enter the emergency mode and run the preset speed, torque limit, mode and enable of the emergency mode; if not, respond to the command issued by the vehicle controller.

[0019] Furthermore, the method includes a first operating cycle and a second operating cycle; wherein the first operating cycle is less than 1 ms; and the second operating cycle is equal to 1 ms.

[0020] Furthermore, during the first operation cycle, a resolver fault is determined. If a fault occurs, the motor speed and position are obtained through an observer; if no fault occurs, the motor speed and position are obtained through a resolver sensor.

[0021] Determine whether the motor speed and position are obtained through the observer. If the motor speed and position are obtained through the observer, switch the motor operating state according to the target speed; if the motor speed and position are not obtained through the observer, switch the motor operating state according to the target torque;

[0022] Determine whether the motor speed and position are obtained through the resolver sensor. If so, the system operates according to the resolver sensor's feedback status. If not, the system enters the no-position operation state.

[0023] Furthermore, during the second operation cycle, a resolver fault is determined. If a fault occurs, the target speed is processed; if no fault occurs, the resolver feedback speed is subjected to mean filtering.

[0024] Determine whether transition processing is required. If not, operate according to the obtained DQ target current; if necessary, transition from the drag current to the speed loop output current according to the transition current step.

[0025] The motor starting method based on angle fitting provided by the embodiment of the present application has the following beneficial technical effects compared with the prior art:

[0026] The embodiment of the present application ensures that the motor can quickly and stably reach the preset angle and speed during the startup process through precise angle fitting and current closed-loop control. This is especially important for motors with large inertia loads, because large inertia loads require greater starting torque and a smoother acceleration process; the embodiment of the present application effectively improves the starting speed and stability of the motor through simulated drag angles, thereby meeting the high requirements of heavy-load equipment such as mixer trucks for motor starting performance.

[0027] The rotary transformer (resolver) in the embodiment of the present application serves as a key sensor, providing accurate feedback information on the motor position and speed. This is crucial when performing I / F (current-frequency) debugging because the debugger can adjust the control parameters based on the real-time data of the resolver sensor to ensure that the motor maintains optimal performance during startup and operation. In addition, because the resolver sensor provides high-precision feedback information, the debugging cycle can be significantly shortened, improving development efficiency.

[0028] The embodiment of the present application achieves a smooth transition during the startup process by smoothing the switching current; during the switching process of the motor from open-loop dragging to closed-loop operation, the method can ensure a smooth change in current and speed, thereby avoiding vibration and impact caused by switching; this is especially important for equipment such as mixer trucks that need to maintain smooth operation of the tank, because vibration may affect the stirring effect and the service life of the tank.

[0029] The embodiments of the present application are not only applicable to motor starting with a position sensor, but also provide a starting strategy in the absence of a position sensor. When the resolver sensor fails or cannot be used, the method can switch to a position-free operating state and rely on an observer to estimate the angle and speed of the motor. This provides a feasible solution to the problem of position-free starting of motors with large inertia loads, thereby improving the flexibility and reliability of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 A flow chart of a motor starting method based on angle fitting according to an embodiment of the present application is shown. DETAILED DESCRIPTION

[0031] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are described in detail below in conjunction with the accompanying drawings. It will be understood that the specific embodiments described herein are only used to explain the present application, rather than to limit the present application. It should also be noted that, for ease of description, only some, rather than all, structures related to the present application are shown in the accompanying drawings. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0032] As used herein, the terms "comprise," "comprising," and "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, method, product, or apparatus.

[0033] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0034] like Figure 1As shown, the embodiment of the present application provides a motor starting method based on angle fitting, comprising the following steps:

[0035] Step 101: Output a preset duty cycle to position the motor at its initial position. During the debugging phase, use the resolver feedback angle to debug the positioning parameters. When the resolver feedback angle is consistent with the preset angle and meets the response requirements, solidify the positioning parameters.

[0036] In the embodiment of the present application, step 101 ensures that the motor can be accurately and quickly positioned during the startup phase, and lays a solid foundation for subsequent drag acceleration and closed-loop operation.

[0037] The main task of step 101 is to obtain the initial positioning of the motor and control the feedback angle of the resolver (resolver) by adjusting the preset duty cycle until the angle reaches the preset value. Once the preset angle is reached, the positioning time and duty cycle settings are determined based on the waveform curve of the resolver feedback angle.

[0038] Before a motor starts, its initial position must be determined. This is typically achieved using a sensor (such as a resolver). The accuracy of this initial position is crucial to the subsequent startup process, as it directly affects the motor's starting performance and stability.

[0039] The duty cycle is the ratio of the time a signal remains high to the total cycle duration within a cycle. In motor control, the duty cycle is typically used to regulate the motor's speed and torque. In step 101, the system outputs a preset duty cycle based on the motor's initial positioning and desired startup performance.

[0040] A resolver is a sensor used to measure the rotation angle of a motor. It can convert the motor's rotation angle into an electrical signal output. In step 101, the resolver's feedback angle is obtained in real time to monitor the actual rotation of the motor. In this embodiment of the application, the resolver's feedback angle is compared with a preset angle. If the feedback angle does not reach the preset angle, it means that the actual rotation of the motor does not meet expectations and needs to be adjusted. If the feedback angle does not reach the preset angle, the preset duty cycle is adjusted according to the current situation. The adjusted duty cycle is re-output to the motor controller to control further rotation of the motor. This process is repeated until the resolver's feedback angle reaches the preset angle.

[0041] Once the resolver's feedback angle reaches the preset angle, the positioning time and duty cycle settings are determined based on the resolver's feedback angle waveform. Positioning time refers to the duration of the positioning duty cycle. The duty cycle setting is determined based on the motor's actual rotation and desired starting performance.

[0042] The embodiments of the present application achieve high-precision motor positioning by acquiring the feedback angle of the resolver in real time and comparing it with the preset angle; quickly adjust the preset duty cycle according to the current situation and re-output it to the motor controller, thereby achieving fast motor response; by continuously adjusting the duty cycle and monitoring the resolver feedback angle, it is possible to ensure that the motor maintains a stable rotation state during the startup process.

[0043] Specifically, the embodiment of the present application determines the time required for positioning by changing the limp W-phase positioning time and the U-phase positioning time, wherein the W-phase positioning time is 0.20S, the U-phase positioning time is 0.50S, and the limp positioning duty cycle step is set to 1%, and the maximum duty cycle is 2.8%.

[0044] In the resolver fault state, the motor startup steps are: positioning - dragging - closed-loop operation. The positioning stage provides a given duty cycle to stop the motor at a known angle. This known angle is the angle set by the dragging stage program. For example, it is first dragged to 90°, then to 60°. This known angle is used as the initial dragging angle. The purpose is to determine the initial angle of the motor when it starts.

[0045] The purpose of the dragging phase is to get the motor spinning. This is because the observer used cannot converge at zero speed or very low speeds. When this fails to converge, the angle and speed output by the observer are inaccurate. Therefore, dragging is performed first, and the closed loop is switched on when the motor speed allows the observer to converge.

[0046] The first step is positioning, and the second step is dragging. These are the two states of motor startup. Both positioning and dragging require reasonable parameters to start the motor, so the relevant parameters need to be debugged. These two steps can be debugged separately during the debugging phase (a stop command is issued after the positioning phase is completed), or they can be debugged together. Generally, the positioning parameters are debugged first, followed by the dragging parameters. When the motor starts running, there are two consecutive states.

[0047] Positioning involves outputting a duty cycle to rotate the motor to the set angle. Debugging requires determining the duty cycle size and duration. If the duty cycle is too small, the motor output torque is too low to rotate. If the duty cycle is too large, the internal current of the motor is too high, risking damage to the motor. If the duty cycle duration is too short, the motor may not be able to rotate to the set angle at the current duty cycle. If the duty cycle duration is too long, the motor startup time is too long and may damage the motor. The response in step 101 refers to the time from the duty cycle output to the motor rotating to the set angle, as shown in the figure below. The response must ensure that the set angle is reached as quickly as possible while minimizing oscillation. The purpose of fixing positioning parameters is to apply the debugged parameters to market products. A prototype vehicle is generally used during the debugging phase. After debugging is completed, the corresponding parameters must be fixed and applied to market vehicles in batches.

[0048] In summary, step 101 ensures high precision, fast response, and stable performance of the motor during the startup phase by obtaining the feedback angle of the resolver in real time, adjusting the preset duty cycle, and determining the positioning time and duty cycle setting value.

[0049] Step 102: The motor is dragged and accelerated based on the set target drag current. The drag current distribution angle is based on the fitting curve. During the debugging phase, the rotary transformer feedback angle is used to debug the drag parameters and fit the angle curve. When the rotary transformer feedback angle is consistent with the drag angle, a drag angle simulation curve is obtained and the drag parameters are solidified.

[0050] Step 102 accelerates the motor using the target drive current. During the debugging phase, the resolver feedback angle, which has reached the preset angle, is used to perform Park and Inverse Park transformations to adjust the drive parameters. This process continues until the resolver feedback angle is completely consistent with the drive angle, at which point a simulated curve for the drive angle is obtained.

[0051] The target drag current is key to the motor's starting output and is used to control the motor's acceleration process. The DQ-axis target current is the target current value for the motor's direct and quadrature axes in the DQ coordinate system. It is used to control the motor's electromagnetic torque and flux linkage. The drag angle is the position angle of the motor's rotor relative to the stator during the drag acceleration process, and it changes over time.

[0052] The Park transform and inverse Park transform are used to convert the motor's three-phase current (or voltage) into the current (or voltage) in the DQ coordinate system and back to the three-phase coordinate system. They are key steps in implementing motor vector control.

[0053] The control parameters of the waveform curve are used to adjust the waveform of motor current, speed and other parameters during the dragging process to ensure that the motor reaches the preset state smoothly and quickly.

[0054] The motor is dragged with the target drag current, and the angle changes during the dragging process are recorded. According to the actual situation during the dragging process, the control parameters of the waveform curve are adjusted to ensure that the motor reaches the preset state smoothly and quickly. The resolver feedback angle and the dragging angle are continuously compared until they are completely consistent. When the resolver feedback angle and the dragging angle are consistent, a simulated curve of the dragging angle can be obtained, indicating the completion of the drag acceleration process.

[0055] Specifically, the target dragging current is set to 30 amperes (A), and the angle is recorded from the time the motor starts dragging. Assuming the initial angle is 0 degrees, the angle gradually increases as the dragging acceleration progresses. The dragging acceleration process lasts for 5 seconds, during which the motor gradually accelerates to the target dragging speed.

[0056] Assuming that the resolver has been calibrated and reaches a preset angle (such as 45 degrees), Park transform and inverse Park transform are performed to convert the three-phase current of the motor into current in the DQ coordinate system for vector control.

[0057] The resolver feedback angle and the drag angle are continuously compared to ensure their consistency. When the difference between the resolver feedback angle and the drag angle is less than a certain threshold (such as 0.1 degrees), they can be considered consistent.

[0058] When the resolver feedback angle is consistent with the drag angle, a simulation curve of the drag angle can be obtained. By analyzing the simulation curve, the performance of the motor during the drag acceleration process, such as acceleration time and stability, can be understood.

[0059] The drag current distribution angle is based on the fitting curve, and the vector control input signal is formed based on the drag current and angle to control the power module, thereby controlling the motor drag. Positionless operation is a state in which a fault in the resolver is detected, which is equivalent to a redundant function of the reliability setting. During the debugging stage, the resolver is fault-free and can provide real feedback on the angle of the motor. During debugging, external conditions are created to first allow the motor control program to run in positionless state, and then the angle feedback from the resolver is used to debug the drag and positioning parameters (external conditions are created, for example: first unplug the resolver connection harness to allow the program to detect the resolver fault, and then reinsert the connection harness after the control program switches to positionless state).

[0060] During positioning, it is necessary to determine whether the output duty cycle will rotate the motor to the set position. The angle of the resolver feedback can be monitored through monitoring software. During the dragging phase, the dragging current is set, and the power module is controlled according to the current loop of the vector control to control the motor drag. Vector control is based on the DQ axis rotating coordinate system. The control power module needs to be converted to the static αβ coordinate system, so the angle of the dragging current must be known. This angle is obtained from the fitting curve. During the debugging phase, the resolver fault is artificially created by the outside world, so its feedback position is reliable. The simulation curve can be determined based on the feedback angle. After the simulation angle curve is determined, it is solidified into the control program. If a resolver fault is detected in a market vehicle, this is a real fault. The resolver feedback angle is unreliable, and the system switches to positionless control. The motor will use the solidified angle simulation curve during the dragging phase of startup.

[0061] In summary, step 102 involves multiple aspects of the motor's acceleration, current control, and vector control. By precisely controlling the speed, adjusting the waveform parameters, and performing other controls, the motor can be ensured to reach the preset state smoothly and quickly, providing strong support for subsequent operation.

[0062] Step 103 : When the motor speed is detected to be higher than the set threshold value for switching to the closed loop during dragging, the closed loop is switched to run, and the dragging current gradually and smoothly transitions to the speed loop output current.

[0063] "Solidifying" the positioning parameters and dragging parameters means that the steps have been completed. Step 103 is equivalent to a transition stage of switching to a closed loop. During dragging in step 102, the program will also monitor the motor rotation speed in real time. When the speed reaches the set speed threshold (this speed threshold is generally the speed at which the observer can converge), it will switch to closed-loop operation. The difference between closed-loop operation and dragging is that the current used for dragging is the control current set by the program, while the current for closed-loop operation is based on the current obtained by the speed loop. If switched directly, when the dragging current differs greatly from the current obtained by the speed loop, it may cause system oscillation, so a transition is added.

[0064] Step 103 describes a key stage in the motor startup process, ie, the process of switching the motor from a startup stage to a closed-loop operation stage.

[0065] This phase means the motor switches from the previous open-loop or drag acceleration phase to the closed-loop control phase. Closed-loop control usually means using feedback signals (such as speed and position) to adjust the motor's operating state to achieve higher control accuracy and stability.

[0066] The embodiment of the present application compares the actual feedback speed with a preset speed value. This preset speed is usually determined based on factors such as the observer, load requirements, and system performance requirements. In motor control, the DQ axis target current is usually used to represent the current component in the rotating coordinate system. When the motor reaches the preset speed, the system needs to convert these target currents into the output current of the speed loop to achieve smoother speed control. After completing the above transition, the motor will run stably under closed-loop control, and its speed will be precisely controlled.

[0067] Step 103 is a key turning point in the motor startup process, marking the transition from the startup phase to the stable operation phase. Through closed-loop control, the system can more accurately control the motor's speed and operating state, thereby improving the performance and stability of the entire motor system.

[0068] Specifically, assume the motor's rated speed is 3000 rpm and its initial speed at startup is 0 rpm. During the motor's acceleration phase, the motor is gradually accelerated through open-loop control. When the motor speed reaches a certain intermediate value, such as 1500 rpm, the motor is determined to be ready for closed-loop operation. The real-time motor speed is monitored, and when it reaches 1500 rpm, the switching condition is triggered, switching to closed-loop control mode. The system converts the target current executed by the system into the speed loop output current.

[0069] During the closed-loop operation phase, the actual motor speed is acquired every 200 us for processing and analysis. A timer is set to trigger every 200 us. When the timer is triggered, the actual motor speed is acquired from the resolver or observer. The read speed data is filtered and processed to remove noise and interference.

[0070] The preset speed is 2800 rpm, and the allowable error range is ±50 rpm. The actual speed is compared with the preset speed. If the actual speed is between 2750 rpm and 2850 rpm (i.e., the preset speed ±50 rpm), it is determined that the preset speed has been reached.

[0071] The DQ axis target current is [Id=1A, Iq=5A], and the speed loop output current limit range is [0A, 10A]. When it is determined that the motor reaches the preset speed, the DQ axis target current begins to transition to the speed loop output current. The transition process realizes the conversion from the drag current to the speed loop output current, such as linear interpolation or exponential interpolation, to ensure that the current change does not cause an impact on the motor. During the transition process, the speed loop output current is monitored in real time to ensure that it does not exceed the limit range.

[0072] In summary, step 103 ensures that the motor can smoothly transition from the startup phase to the closed-loop operation phase, and achieves precise control of the motor speed.

[0073] Furthermore, in an embodiment of the present application, when the motor is starting up, if a resolver fault record is detected in the memory, the motor will immediately switch to a position-free operation state. In the position-free operation state, the motor will rely on the observer to estimate its angle and speed to ensure that the motor can continue to operate stably.

[0074] If a resolver fault is detected before the motor starts but there is no record of it in the memory, the system will also switch to the no-position operation state. This strategy ensures that the motor can react quickly to potential faults and avoids any adverse effects on motor operation.

[0075] If a resolver fault is detected during motor startup, the motor will be shut down before switching to non-position operation. The shutdown protects the motor from further damage caused by the fault, while switching to non-position operation ensures the motor can continue to operate even in the event of a fault.

[0076] If no resolver fault is detected during motor startup, the motor will continue to operate based on the angle and speed information provided by the resolver sensor. This ensures that the motor maintains high accuracy and stability during normal operation.

[0077] After the motor switches from startup operation to position-free operation, if it detects that the resolver fault has recovered, it will continue in position-free operation and rely on the observer to estimate the motor angle and speed. This is because even if the resolver fault has recovered, it has already switched to position-free operation. To avoid instability caused by the sudden switch, the current state will be maintained.

[0078] In an embodiment of the present application, information such as the command speed, torque limit, mode and enable issued by the vehicle controller is received, and the operating state of the motor is adjusted according to this information. In the positionless operating state, if the motor switches forward and reverse, it will determine whether the host computer instruction is consistent with the actual operating direction, and decide whether to shut down and then respond to the command speed based on the judgment result. This ensures that the motor can transition smoothly when switching directions to avoid excessive shock and vibration. It will also determine whether there is a communication failure. If there is a communication failure, it will enter the emergency mode and run the motor according to the speed, torque limit, mode and enable preset in the emergency mode. This ensures that the motor can continue to operate in the event of a communication failure and maintain a certain degree of stability and safety.

[0079] In the embodiment of the present application, two operating cycles are included: the first operating cycle is less than 1ms, which is used for rapid fault judgment and state switching; the second operating cycle is equal to 1ms, which is used for mean filtering of the resolver feedback speed.

[0080] During the first operating cycle, a resolver fault diagnosis is performed, and based on the result, the system chooses whether to obtain motor speed and position information through an observer or a resolver sensor. This ensures a quick response to a fault and a switch to the appropriate operating state.

[0081] During the second operating cycle, the resolver feedback speed undergoes mean filtering to reduce the impact of noise and interference on motor operation. The system also determines whether transition processing is necessary to ensure a smooth transition between motor operating states. If a fault occurs, the target speed is set using small steps before switching to closed-loop control and larger steps afterward. During the drag phase of high-inertia loads, the actual speed response is slow. Small steps are used for slow drag, while larger steps are used after switching to closed-loop control to improve the system's response to the target speed.

[0082] These strategies ensure that the motor can quickly respond to various fault conditions and switch to the appropriate operating state to maintain motor stability and safety. At the same time, it can also receive instructions from the vehicle controller and adjust the motor's operating state accordingly to meet different operating requirements.

[0083] In summary, the embodiment of the present application is a motor starting method based on angle fitting, so the main explanation focuses on the motor starting steps: positioning-drag-closed loop operation. The main problem solved by the embodiment of the present application is the application of position-free control to the starting of a motor with a large inertia load. The initial state is affected by the large inertia load, the actual rotor of the motor rotates slowly, and the angle obtained by the target drag speed deviates greatly from the actual angle, which can easily cause dragging to lose step and lead to startup failure. In response to this, a solution is proposed: using a simulated angle curve during dragging. This simulated curve is determined by the actual feedback angle of the rotary transformer during the debugging phase. According to this angle, the success rate of the motor startup can be improved, and the positioning parameters are also determined based on the actual angle. Compared with traditional debugging solutions, the debugging cycle is greatly shortened, which is very important in actual project development. Angle fitting is determined based on the feedback angle of the rotary transformer during the debugging phase. Through the monitoring interface, the drag current size, action time, speed action step, and switching speed setting value are modified in real time to make the drag angle consistent with the feedback angle of the rotary transformer.

[0084] It should be noted that, in the present application, the terms "comprise", "include" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the statement "comprises a ..." does not exclude the presence of other identical elements in the process, method, article or device comprising the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in the opposite order according to the functions involved. For example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0085] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are within the protection of this application.

Claims

1. A motor starting method based on angle fitting, characterized in that: The method comprises: Output a preset duty cycle to locate the initial position of the motor. During the debugging phase, use the resolver feedback angle to debug the positioning parameters. When the resolver feedback angle is consistent with the preset angle and meets the response requirements, solidify the positioning parameters. The motor is dragged and accelerated based on the set target drag current. The drag current distribution angle is based on the fitting curve. During the debugging phase, the rotary transformer feedback angle is used to debug the drag parameters and fit the angle curve. When the rotary transformer feedback angle is consistent with the drag angle, a drag angle simulation curve is obtained to solidify the drag parameters. When the motor speed is detected to be higher than the set threshold for switching to the closed loop during dragging, the closed loop is switched to run, and the dragging current gradually and smoothly transitions to the speed loop output current.

2. The motor starting method based on angle fitting according to claim 1, characterized in that: The method comprises: When the motor starts running, fault detection is performed. If a resolver fault is detected in the memory, it will directly switch to position-free operation and run at the angle and speed obtained by the observer.

3. The motor starting method based on angle fitting according to claim 1, characterized in that: The method comprises: When the motor starts running, fault detection is performed. If it is detected that there is no resolver fault in the memory, but a resolver fault is detected before running, it will directly switch to positionless operation and run at the angle and speed obtained by the observer.

4. The motor starting method based on angle fitting according to claim 1, characterized in that: The method comprises: When the motor starts running, fault detection is performed. If it is detected that there is no resolver fault in the memory, but a resolver fault is detected during operation, the motor is first stopped and then switched to positionless operation, running at the angle and speed obtained by the observer.

5. The motor starting method based on angle fitting according to claim 1, characterized in that: The method comprises: When the motor starts running, fault detection is performed. If it is detected that there is no resolver fault in the memory and no resolver fault is detected during operation, the motor runs at the angle and speed obtained by the resolver.

6. The motor starting method based on angle fitting according to claim 1, characterized in that: The method comprises: When the motor switches from startup operation to position-free operation, if the resolver fault recovery is detected, it will still run in position-free mode and at the angle and speed obtained by the observer.

7. The motor starting method based on angle fitting according to any one of claims 2 to 6, characterized in that: The method comprises: Receive command speed, torque limit, mode and enable from the vehicle controller; Determine whether the motor switches forward or reverse in the no-position operation state. If so, determine whether the host computer command is consistent with the actual operation direction. If they are consistent, directly respond to the command speed; if not, first stop the motor and then respond to the command speed; if no forward or reverse switching occurs, directly respond to the command speed; After responding to the command speed, determine whether there is a communication fault. If so, enter the emergency mode and run the preset speed, torque limit, mode and enable of the emergency mode; if not, respond to the command issued by the vehicle controller.

8. The motor starting method based on angle fitting according to claim 7, characterized in that: The method includes a first operating cycle and a second operating cycle; wherein the first operating cycle is less than 1 ms; and the second operating cycle is equal to 1 ms.

9. The motor starting method based on angle fitting according to claim 8, characterized in that: During the first operation cycle, a resolver fault is determined. If a fault occurs, the motor speed and position are obtained through an observer; if no fault occurs, the motor speed and position are obtained through a resolver sensor. Determine whether the motor speed and position are obtained through the observer. If the motor speed and position are obtained through the observer, switch the motor operating state according to the target speed; if the motor speed and position are not obtained through the observer, switch the motor operating state according to the target torque; Determine whether the motor speed and position are obtained through the resolver sensor. If so, the system operates according to the resolver sensor's feedback status. If not, the system enters the no-position operation state.

10. The motor starting method based on angle fitting according to claim 8, characterized in that: During the second operation cycle, a resolver fault is determined, and if a fault occurs, the target speed is processed; If no fault occurs, perform mean filtering on the resolver feedback speed; Determine whether transition processing is required. If not, operate according to the obtained DQ target current; If necessary, transition from the drag current to the speed loop output current according to the transition current step.

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