A motor starting method based on angle fitting

Abstract

The application discloses a motor starting method based on angle fitting, and relates to the technical field of motor starting. The method ensures quick and stable starting of a motor through fine angle fitting and current closed-loop control, and is particularly suitable for a motor with a large inertia load. The method comprises the following steps of motor initial positioning, dragging acceleration, closed-loop operation and the like. When debugging, a control parameter is adjusted by using a rotary transformer (rotary transformer) feedback. When starting and operating, monitoring and fault handling are implemented. According to the rotary transformer fault, the method is switched to positionless operation. In addition, the method also considers forward and reverse switching under positionless operation and communication fault handling, and improves the flexibility and reliability of the system.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of motor starting, and particularly relates to a motor starting method based on angle fitting. BACKGROUND

[0002] At present, some upper controllers based on actual application scenarios have special working condition function requirements. When a rotary transformer fails, the mixing drum cannot run, which leads to the risk of solidification of the concrete in the mixing drum, and the upper controller does not have a redundant limp function.

[0003] In the current mainstream position sensorless control, there is a large deviation between the estimated angle of the rotor at low speed and the actual real angle. If the estimated angle is directly used for starting, the stability of the motor will be greatly affected, and even the motor will be out of step. The current common starting method of position sensorless control mainly includes high-frequency injection method and open-loop starting method. The open-loop starting mainly uses voltage-to-frequency ratio (V / F) control and current-to-frequency ratio (I / F) control. I / F control is an open-loop control algorithm based on V / F control. It can effectively prevent current overshoot and realize closed-loop control of motor working current by using its inherent self-stability between torque and rotor position. However, due to the lack of the ability to adjust the virtual q-axis current according to the load change, it is only suitable for short-time low-speed starting process. It is mainly used to assist in realizing the stable starting of PMSM.

[0004] In the I / F dragging stage, the angle of current application is obtained from the target dragging speed. When it is applied to the starting of a motor with large inertia load, the actual rotor rotation of the motor is slow due to the influence of the large inertia load, and the angle obtained from the target dragging speed has a large deviation from the actual angle, which easily leads to dragging out of step and starting failure. SUMMARY

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

[0006] In order to achieve the above purpose, the motor starting method based on angle fitting provided by the embodiments of the application comprises:

[0007] The initial position of the motor is positioned by outputting a preset duty ratio. In the debugging stage, the angle of the rotary transformer is fed back, the positioning parameters are debugged, the angle of the rotary transformer is consistent with the preset angle, and the response is met, and the positioning parameters are solidified.

[0008] The motor is accelerated by dragging based on the set target dragging current. The dragging current distribution angle is based on the fitting curve. In the debugging stage, the angle of the rotary transformer is fed back, the dragging parameters are debugged, the angle curve is fitted, the angle of the rotary transformer is consistent with the dragging angle, the dragging angle simulation curve is obtained, and the dragging parameters are solidified.

[0009] When the motor speed is detected to be higher than the set threshold of the cut-off ring during the dragging, the cut-off ring is operated, and the dragging current gradually transits to the speed ring output current for smooth transition.

[0010] The method according to the embodiment of the application can further have the following additional technical features.

[0011] Further, when the motor is started and operated, fault detection is performed. If it is detected that there is a resolver fault in the memory, the motor is directly switched to the positionless operation to run at the angle and speed obtained by the observer.

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

[0013] Further, when the motor is started and operated, 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 stopped first, and then switched to the positionless operation to run at the angle and speed obtained by the observer.

[0014] Further, when the motor is started and operated, 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 is operated at the angle and speed obtained by the resolver.

[0015] Further, when the motor is switched from the start operation to the positionless operation, if it is detected that the resolver fault is recovered, the motor is still operated in the positionless operation and at the angle and speed obtained by the observer.

[0016] Further, the instruction speed, torque limit, mode and enable issued by the vehicle controller are received.

[0017] It is judged whether the motor appears positive and negative rotation switching in the positionless operation state. If the positive and negative rotation switching appears, it is judged whether the instruction of the upper computer and the actual running direction are consistent. If they are consistent, the instruction speed is directly responded. If they are not consistent, the motor is stopped first, and then the instruction speed is responded. If the positive and negative rotation switching does not appear, the instruction speed is directly responded.

[0018] After the instruction speed is responded, it is judged whether there is a communication fault. If there is, the emergency mode is switched in, and the speed, torque limit, mode and enable preset in the emergency mode are operated. If there is not, the instruction issued by the vehicle controller is responded.

[0019] Further, the method comprises a first operation period and a second operation period. The first operation period is less than 1 ms, and the second operation period is equal to 1 ms.

[0020] Further, in the first running cycle, a resolver fault judgment is performed, 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] It is judged whether the motor speed and position are obtained through the observer, if the motor speed and position are obtained through the observer, the motor running state is switched according to the target speed; if the motor speed and position are not obtained through the observer, the motor running state is switched according to the target torque;

[0022] It is judged whether the motor speed and position are obtained through the resolver sensor, if the motor speed and position are obtained through the resolver sensor, the motor is run according to the feedback state of the resolver sensor; if the motor speed and position are not obtained through the resolver sensor, a positionless running state is entered.

[0023] Further, in the second running cycle, a resolver fault judgment is performed, if a fault occurs, the target speed is processed; if no fault occurs, the resolver feedback speed is processed by mean filtering;

[0024] It is judged whether transition processing is needed, if not, the obtained DQ target current is run; if needed, the transition current step is used to output current transition from the drag current to the speed loop.

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

[0026] The embodiment of the application ensures that the motor can quickly and stably reach the preset angle and speed in the starting process through fine angle fitting and current closed-loop control, which is particularly important for motors with large inertia loads, because large inertia loads require greater starting torque and more stable acceleration process; the embodiment of the application effectively improves the starting speed and stability of the motor through the simulated drag angle, thereby meeting the high requirements of heavy equipment such as mixers on the starting performance of the motor.

[0027] The resolver (resolver) of the embodiment of the application provides accurate feedback information of the motor position and speed as a key sensor, which is crucial when performing I / F (current-frequency) debugging, because the debugging personnel can adjust the control parameters according to the real-time data of the resolver sensor, thereby ensuring that the motor maintains optimal performance during starting and running; in addition, since the resolver sensor provides high-precision feedback information, the debugging period is significantly shortened, improving development efficiency.

[0028] The embodiment of the present application realizes smooth transition in the starting process through the smooth processing of the switching current. In the switching process from open-loop dragging to closed-loop operation of the motor, the method can ensure smooth changes of the current and the speed, thereby avoiding vibration and impact caused by switching. This is particularly important for mixers and other devices that need to keep the tank body running smoothly, because vibration can affect the mixing effect and the service life of the tank body.

[0029] The embodiment of the present application is not only applicable to motor starting with a position sensor, but also provides a starting strategy in the case of no position sensor. When the resolver sensor fails or cannot be used, the method can be switched to a positionless running state and rely on an observer to estimate the angle and speed of the motor. This provides a feasible solution to the problem of positionless starting of a motor with a large inertia load, and improves the flexibility and reliability of the system. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 A flowchart 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 purposes, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application will be described in detail below with reference to the drawings. It can be understood that the specific embodiments described herein are only used to explain the present application, but not to limit the present application. In addition, it should be noted that, in order to facilitate description, only parts related to the present application are shown in the drawings, rather than all structures. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0032] The terms "comprising" and "having" and any variations thereof in the present application are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to these processes, methods, products or devices.

[0033] In the present application, the phrase "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase at various places in the specification does not necessarily mean the same embodiment, nor is it an independent or alternative embodiment to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described in the present application can be combined with other embodiments.

[0034] As 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 locate the initial position of the motor, use the resolver feedback angle in the debugging stage, debug the positioning parameters, wait for the resolver feedback angle to be consistent with the preset angle, and meet the response, and solidify the positioning parameters.

[0036] In the embodiment of the present application, step 101 ensures that the motor can be accurately and quickly positioned in the starting stage, 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 the set value of the duty cycle are determined according to the waveform curve of the resolver feedback angle.

[0038] Before the motor starts, the initial position of the motor needs to be determined first. This is usually achieved through a sensor such as a resolver. The accuracy of the initial positioning is crucial for the subsequent starting process, as it directly affects the starting performance and stability of the motor.

[0039] Duty cycle refers to the ratio of the time during which the signal is high to the entire cycle time. In motor control, duty cycle is often used to adjust the speed and torque of the motor. In step 101, a preset duty cycle is output according to the initial positioning of the motor and the desired starting performance.

[0040] The resolver is a sensor used to measure the rotational angle of the motor. It can convert the rotational angle of the motor into an electrical signal output. In step 101, the feedback angle of the resolver is obtained in real time to monitor the actual rotation of the motor. The feedback angle of the resolver is compared with the preset angle in the embodiment of the present application. If the feedback angle does not reach the preset angle, it means that the actual rotation of the motor does not meet the 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 output to the motor controller to control the further rotation of the motor. This process is repeated until the feedback angle of the resolver reaches the preset angle.

[0041] Once the feedback angle of the resolver reaches the preset angle, the positioning time and the set value of the duty cycle are determined according to the waveform curve of the resolver feedback angle. The positioning time is the time for which the positioning duty cycle acts. The set value of the duty cycle is determined according to the actual rotation of the motor and the desired starting performance.

[0042] The embodiment of the application realizes high-precision motor positioning by comparing the feedback angle of the resolver with the preset angle in real time; the preset duty cycle is quickly adjusted according to the current situation and is re-output to the motor controller, so that fast motor response is realized; by continuously adjusting the duty cycle and monitoring the resolver feedback angle, the motor can be ensured to maintain a stable rotating state during the starting process.

[0043] Specifically, the embodiment of the application determines the time length required for positioning by changing the 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 set to 2.8%.

[0044] In the resolver fault state, the motor starting steps are: positioning-dragging-closing the loop operation. The positioning stage provides a given duty cycle to make the motor stop at a known angle. This known angle is the angle set in the dragging stage program, for example, first dragging to 90°, and then to 60°. This known angle serves as the initial angle of dragging. The purpose is to determine the initial angle of the motor when the motor starts.

[0045] The dragging stage is mainly to make the motor rotate. The main reason is that the observer used cannot converge at 0 speed and ultra-low speed, and the angle and speed output by the observer are not accurate when it cannot converge. Therefore, dragging is performed first, and the motor speed is cut into the closed loop when the observer can converge.

[0046] The first step is positioning, and the second step is dragging, which are two states of motor starting. Both positioning and dragging need some reasonable parameters to make the motor start, so related parameters need to be debugged. The two steps can be debugged separately (stop the machine after completing the positioning stage) or together. Generally, the positioning parameters are debugged first, and then the dragging parameters are debugged. The motor starting operation is continuous in two states.

[0047] Positioning is to output a duty cycle to make the motor rotate to a set angle. The size and action time of the duty cycle need to be determined during debugging. If the duty cycle is too small, the torque output by the motor is small and the motor cannot rotate. If the duty cycle is too large, the current in the motor is too large and there is a risk of damaging the motor. If the action time of the duty cycle is too short, the motor may not be able to rotate to the set angle under the current duty cycle. If the action time of the duty cycle is too long, the motor starting time is too long and there is a risk of damaging the motor. The response of step 101 outputs the duty cycle to the time when the motor rotates to the set angle, as shown in the following figure. The response needs to meet the requirement of reaching the set angle faster under the premise of small oscillation. The purpose of fixing the positioning parameters is mainly to apply the debugged reasonable parameters to market products. During the debugging stage, a sample vehicle is generally used. After debugging is completed, the corresponding parameters need to 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 starting stage by real-time acquisition of the feedback angle of the rotary transformer, adjustment of the preset duty ratio, and determination of the positioning time and duty ratio setting value.

[0049] In step 102, the motor is accelerated based on the set target drag current. The drag current distribution angle is determined according to the fitting curve. In the debugging stage, 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 fixed.

[0050] Step 102 is to accelerate the motor based on the target drag current. In the debugging stage, the rotary transformer feedback angle that has reached the preset angle is used for Park Transformation and Inverse Park Transformation to debug the drag parameters. This process will continue until the rotary transformer feedback angle is completely consistent with the drag angle, at which point the drag angle simulation curve can be obtained.

[0051] The target drag current is the key to the motor starting output, which is used to control the acceleration process of the motor. The DQ-axis target current is the target current value of the motor direct axis and cross axis in the DQ coordinate system, which is used to control the electromagnetic torque and flux linkage of the motor. The drag angle is the position angle of the motor rotor relative to the stator during the drag acceleration process, which changes with time.

[0052] Park Transformation and Inverse Park Transformation are two transformations used to convert the three-phase current (or voltage) of the motor into the DQ coordinate system and convert the DQ coordinate system current (or voltage) back to the three-phase coordinate system. They are the key steps to realize motor vector control.

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

[0054] The motor is dragged based on the target drag current, and the angle change during the drag process is recorded. According to the actual situation during the drag process, the waveform curve control parameters are adjusted to ensure that the motor reaches the preset state smoothly and quickly. The rotary transformer feedback angle and the drag angle are constantly compared until they are completely consistent. When the rotary transformer feedback angle and the drag angle are consistent, the drag angle simulation curve is obtained, indicating the completion of the drag acceleration process.

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

[0056] Assuming the resolver has been calibrated and reaches the preset angle (e.g., 45 degrees), at this time, the Park transformation and inverse Park transformation are performed to convert the motor's three-phase current into the current in the DQ coordinate system for vector control.

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

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

[0059] The drag current distribution angle is based on the fitting curve, and the vector control input signal is composed of the drag current and the angle. The power module is controlled to control the motor drag. The no-position operation is a redundant function set for reliability when the resolver is detected to be faulty. In the debugging stage, the resolver is fault-free and can truly feedback the motor angle. During debugging, the motor control program is first run in no-position by externally creating conditions, and then the parameters for drag and positioning are adjusted using the resolver feedback angle (by externally creating conditions, such as disconnecting the resolver connection harness to make the program detect resolver failure, and then reconnecting the connection harness after the control program switches to no-position)

[0060] During positioning, it needs to be clear whether the output duty cycle will turn the motor to the set position. The resolver feedback angle can be monitored through monitoring software. During the drag stage, the drag current is set, the power module is controlled according to the current loop of vector control, and the motor is dragged. Vector control is based on the DQ axis rotating coordinate system, and the power module needs to be converted to the static αβ coordinate system, so the angle of the drag current needs to be known, which is obtained from the fitting curve. In the debugging stage, the resolver failure is artificially created by the outside world, so the feedback position is reliable, and 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. When the resolver failure is detected in the market vehicle, it is a real failure, and the resolver feedback angle is unreliable. The system switches to no-position control, and the motor uses the solidified angle simulation curve during the drag stage of starting.

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

[0062] Step 103, when the motor speed is detected to be higher than the set threshold of the closed loop during the drag, the closed loop operation is cut off, and the drag current gradually transitions to the speed loop output current.

[0063] The "solidification" positioning parameters and the drag parameters have been completed, and step 103 is equivalent to a transition stage of cutting off the closed loop. During step 102, the program also monitors the motor rotation speed in real time. When the rotation speed reaches the set rotation speed threshold (which is usually the rotation speed at which the observer can converge), the closed loop operation is cut in. The difference between the closed loop operation and the drag is that the current used in the drag is the control current set by the program, while the current used in the closed loop operation is obtained based on the speed loop. If the drag current and the current obtained by the speed loop are significantly different, it may cause system oscillation, so a transition is added.

[0064] Step 103 describes a key stage in the motor starting process, namely the process of switching the motor from a certain starting stage to a closed loop operation stage.

[0065] This stage means that the motor is switched from the previous open loop or drag acceleration stage to the closed loop control stage. Closed loop control usually means using feedback signals (such as speed, position, etc.) to adjust the operation state of the motor 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 according to the observer, load requirements, and system performance requirements. In motor control, 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 stably operate under closed loop control, and its speed will be accurately controlled.

[0067] Step 103 is a key turning point in the motor starting process, which marks the transition of the motor from the starting stage to the stable running stage. Through closed loop control, the system can more accurately control the speed and operation state of the motor, thereby improving the performance and stability of the entire motor system.

[0068] Specifically, assuming that the rated speed of the motor is 3000 rpm and the initial speed at startup is 0 rpm. During the motor drag acceleration phase, the motor is gradually accelerated through open-loop control. When the motor speed reaches a certain intermediate value, such as 1500 rpm, it is determined that the motor has the conditions to switch to closed-loop operation. The real-time speed of the motor is monitored, and when the speed reaches 1500 rpm, the switching condition is triggered, and the system switches to closed-loop control mode, and the target current executed by the system is converted to speed loop output current.

[0069] In the closed-loop operation phase, the actual speed of the motor is obtained every 200us and processed and analyzed, and a timer is set to trigger every 200us. When the timer triggers, the actual speed of the motor is obtained from the rotary transformer or observer, and 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, and if the actual speed is between 2750 rpm and 2850 rpm (i.e. ±50 rpm of the preset speed), it is determined that the preset speed is 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 transition of the DQ axis target current to the speed loop output current is started, and 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 will not cause impact to the motor. During the transition process, the size of the speed loop output current is monitored in real time, and it is ensured 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 realizes accurate control of the motor speed.

[0073] Further, in the embodiments of the present application, when the motor is running at startup, if it is detected that there is a fault record of the rotary transformer (rotary transformer) in the memory, it will immediately switch to a positionless running state. In the positionless running state, the motor will rely on the observer to estimate its angle and speed to ensure that the motor can continue to run stably.

[0074] If the rotary transformer fault is detected before the motor starts, but there is no related record in the memory, it will also switch to a positionless running state. This strategy ensures that the motor can quickly respond when facing potential faults, avoiding adverse effects of the fault on the motor operation.

[0075] In the process of motor starting operation, if the resolver fault is detected suddenly, the motor will be stopped first, and then switched to the positionless running state. The stop operation is to protect the motor from further damage caused by the fault, and the switching to the positionless running state is to ensure that the motor can continue to run in the fault condition.

[0076] If no resolver fault is detected during the motor starting operation, the motor will continue to rely on the angle and speed information provided by the resolver sensor to run. This ensures that the motor can maintain high precision and stability in normal operation state.

[0077] When the motor is switched from starting operation to positionless running, if it is detected that the resolver fault has recovered, it will continue to maintain the positionless running state and rely on the observer to estimate the angle and speed of the motor. This is because even if the resolver fault has recovered, it has been switched to the positionless running state, in order to avoid the instability factors that may be caused by sudden switching, the current state will be maintained to continue running.

[0078] In the embodiments of the present application, the instruction speed, torque limit, mode and enable information issued by the vehicle controller are received, and the running state of the motor is adjusted according to these information. In the positionless running state, if the motor appears positive and negative reverse switching, it will be judged whether the host computer instruction and the actual running direction are consistent, and according to the judgment result, it will be decided whether to stop after responding to the instruction speed. This ensures that the motor can smoothly transition when switching direction, avoiding excessive impact and vibration. It will also be judged whether there is a communication fault. If there is a communication fault, it will switch to the emergency mode, and run the motor according to the preset speed, torque limit, mode and enable of the emergency mode. This ensures that the motor can continue to run in the communication fault condition, and maintains a certain stability and safety.

[0079] In the embodiments of the present application, there are two running periods: the first running period is less than 1ms, which is used for fast fault judgment and state switching; the second running period is equal to 1ms, which is used for mean filtering processing of resolver feedback speed.

[0080] In the first running period, resolver fault judgment will be performed, and according to the judgment result, it will be selected whether to obtain the speed and position information of the motor through the observer or the resolver sensor. This ensures that when facing a fault, it can quickly respond and switch to the appropriate running state.

[0081] In the second operating cycle, the resolver feedback speed is subjected to mean filtering to reduce the impact of noise and interference on motor operation. At the same time, the system also determines whether transition processing is needed to ensure smooth transition of the motor when switching operating states. If there is a fault, the target speed uses a small step before the closed loop is cut, and a large step after the closed loop is cut. In the large inertia load dragging stage, the actual speed response is slow, so a small step is used for slow dragging, and a large step is used after the closed loop is cut to improve the system's response to the target speed.

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

[0083] In summary, the embodiment of the present application is a motor starting method based on angle fitting, so it mainly focuses on the motor starting steps: positioning-dragging-closed loop operation. The main problem solved by the embodiment of the present application is that the position control is applied to the motor starting of large inertia load, the actual rotor rotation of the motor is slow, the angle of the target dragging speed obtained is greatly deviated from the actual value, and the dragging step loss easily leads to starting failure. A solution is proposed: an analog angle curve is used during dragging, this analog curve is determined using the real feedback angle of the resolver during the debugging stage, the starting success rate of the motor can be improved according to this angle, and the positioning parameters are also determined based on the actual angle. Compared with the traditional debugging scheme, the debugging period is greatly shortened, which is very important in actual project development. Angle fitting is determined based on the resolver feedback angle in the debugging stage. Through the monitoring interface, the dragging current size, action time, speed action step, and switching speed setting value are modified in real time, so that the dragging angle is consistent with the resolver feedback angle.

[0084] It should be noted that, in the present application, the terms "comprising", "containing" or any other variant thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element. In addition, it should be noted that the scope of the methods and apparatus in the present application is not limited to performing functions in the order shown or discussed, but can also include performing functions in a substantially simultaneous manner or in reverse order, for example, the described methods can be performed in an order different from that described, and various steps can also be added, omitted, or combined. In addition, features described with reference to certain examples can be combined in other examples.

[0085] The embodiments of the present application are described above with reference to the accompanying drawings, but the present application is not limited to the specific embodiments described above, which are merely illustrative and not restrictive, and a person of ordinary skill in the art can make many forms under the inspiration of the present application without departing from the scope of the present application and the scope protected by the claims.

Claims

1. A method of motor starting based on angle fitting, characterized in that, The method comprises: Outputting a preset duty cycle positioning motor initial position, using a rotary transformer feedback angle in a debugging stage, debugging positioning parameters, waiting for the rotary transformer feedback angle to be consistent with a preset angle and to meet a response, and solidifying the positioning parameters; Based on a set target drag current, the motor is accelerated, a drag current distribution angle is determined according to a fitting curve, a rotary transformer feedback angle is used in a debugging stage to debug drag parameters, an angle curve is fitted, the rotary transformer feedback angle is consistent with a drag angle, a drag angle simulation curve is obtained, and the drag parameters are solidified; When the motor speed is higher than a set threshold value of a closed loop during the dragging, the closed loop is switched to run, and the drag current is gradually changed to a speed loop output current for smooth transition.

2. The angle fitting based motor starting method of claim 1, wherein, The method comprises: When the motor is started and runs, fault detection is performed, if it is detected that there is a rotary transformer fault in the memory, the motor is directly switched to run without position, and the angle and speed obtained by the observer are run.

3. The angle fitting based motor starting method of claim 1, wherein, The method comprises: When the motor is started and runs, fault detection is performed, if it is detected that there is no rotary transformer fault in the memory, but a rotary transformer fault is detected before running, the motor is directly switched to run without position, and the angle and speed obtained by the observer are run.

4. The angle fitting based motor starting method of claim 1, wherein, The method comprises: When the motor is started and runs, fault detection is performed, if it is detected that there is no rotary transformer fault in the memory, but a rotary transformer fault is detected during running, the motor is stopped first, then switched to run without position, and the angle and speed obtained by the observer are run.

5. The angle fitting based motor starting method of claim 1, wherein, The method comprises: When the motor is started and runs, fault detection is performed, if it is detected that there is no rotary transformer fault in the memory, and no rotary transformer fault is detected during running, the angle and speed obtained by the rotary transformer are run.

6. The angle fitting based motor starting method of claim 1, wherein, The method comprises: When the motor is switched from starting to running without position, if it is detected that the rotary transformer fault is recovered, the motor is still run without position, and the angle and speed obtained by the observer are run.

7. A method of motor starting based on angle fitting according to any of claims 2-6, characterized in that, The method comprises: Receiving an instruction speed, torque limit, mode and enablement issued by a vehicle controller; Judging whether the motor appears positive and negative rotation switching in the running without position state, if the positive and negative rotation switching appears, judging whether the instruction of the upper computer and the actual running direction are consistent, if they are consistent, directly responding to the instruction speed, if they are not consistent, stopping the motor first, then responding to the instruction speed, if the positive and negative rotation switching does not appear, directly responding to the instruction speed; After responding to the instruction speed, judging whether there is a communication fault, if there is, switching to an emergency mode, running the preset speed, torque limit, mode and enablement of the emergency mode, if there is not, responding to the instruction issued by the vehicle controller.

8. The angle fitting based motor starting method of claim 7, wherein, The method comprises a first running period and a second running period; wherein the first running period is less than 1ms; and the second running period is equal to 1ms.

9. The angle fitting based motor starting method of claim 8, wherein, In the first running period, judging whether there is a rotary transformer fault, if there is a fault, obtaining the motor speed and position through an observer, if there is no fault, obtaining the motor speed and position through a rotary transformer sensor; In the first running period, judging whether there is a rotary transformer fault, if there is a fault, obtaining the motor speed and position through an observer, if there is no fault, obtaining the motor speed and position through a rotary transformer sensor; Judging whether the motor speed and position are acquired through the observer, if the motor speed and position are acquired through the observer, switching the motor running state according to the target speed, if the motor speed and position are not acquired through the observer, switching the motor running state according to the target torque; Judging whether the motor speed and position are acquired through the resolver sensor, if the motor speed and position are acquired through the resolver sensor, running according to the feedback state of the resolver sensor, if the motor speed and position are not acquired through the resolver sensor, entering the positionless running state.

10. The angle fitting based motor starting method of claim 8, wherein, During the second running period, judging the resolver fault, if fault, processing the target speed; If no fault occurs, performing the mean filtering processing on the resolver feedback speed; Judging whether the transition processing is needed, if not, running according to the acquired DQ target current; If needed, performing the current transition from the drag current to the speed loop output current according to the transition current step.

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