Motor controller protection method, device, equipment, storage medium and computer program product

Abstract

The present application discloses a motor controller protection method, device, equipment, storage medium and computer program product, which relate to the field of motor control technology. When the motor controller protection method detects that the motor controller needs to execute an active short-circuit strategy, it determines each bridge arm that needs to be short-circuited and the current real-time speed of the motor, and obtains the initial duty cycle required for each bridge arm that needs to be short-circuited corresponding to the current speed of the motor based on the peak torque and peak power of the motor, and then gradually adjusts the initial duty cycle of each bridge arm to the maximum duty cycle through a corresponding preset number of steps, so that each bridge arm gradually completes the short-circuit process, thereby suppressing the peak current generated by the instantaneous switching of the on and off states of the power tube in the bridge arm, reducing the impact of the peak current on the motor controller, and extending the service life of the motor controller.

Description

Technical Field

[0001] The present application relates to the field of motor control technology, and in particular to a motor controller protection method, device, equipment, storage medium and computer program product. Background Art

[0002] With the continuous development of science and technology, motors have been popularized in every corner of people's lives, especially in some places where machines need to provide a lot of power, such as the drive system of automobiles. In order to improve power output, people have gradually adopted high-power density permanent magnet synchronous motors to replace traditional motors. In order to ensure that such high-power density motors can drive safely, it is usually required that the motor controller can shut down the motor output when a fault occurs, so that the motor torque is close to zero. When the motor is at low speed, it can be achieved by directly shutting down the bridge arms of the three-phase bridge in the motor controller. However, when the motor is at high speed, if the bridge arms of the three-phase bridge are quickly shut down, the motor will generate back electromotive force, which will cause the current formed by the back electromotive force generated by the motor to flow back to the battery through the freewheeling diode of the three-phase bridge, thereby generating a large braking torque. Usually, the upper bridge arms of the motor controller can be controlled to be short-circuited or the lower bridge arms can be short-circuited by active short-circuiting, thereby reducing the motor output torque. However, due to reasons such as the electrical parameters of the device, even if it is processed in this way, a large peak current may still be generated to impact the circuit components in the motor controller, causing damage to the motor controller or the motor. Summary of the invention

[0003] The main purpose of the present application is to provide a motor controller protection method, device, equipment, storage medium and computer program product, aiming to solve the technical problem of how to reduce the peak current generated by the motor controller during the active short circuit process.

[0004] To achieve the above object, the present application provides a motor controller protection method, the steps of the motor controller protection method comprising:

[0005] When it is detected that the motor controller needs to execute an active short-circuit strategy, each bridge arm to be short-circuited in the motor controller is determined, and the real-time speed of the current motor is obtained;

[0006] Based on the real-time rotation speed, the peak torque and the peak power of the motor, determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited;

[0007] Based on a preset number of steps, the real-time duty cycle of each of the bridge arms to be short-circuited is gradually adjusted from the initial duty cycle to the maximum duty cycle, so that each of the bridge arms to be short-circuited is gradually fully short-circuited.

[0008] In one embodiment, the step of determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time rotation speed, the peak torque and the peak power of the motor comprises:

[0009] Based on the real-time rotation speed, the peak torque and the peak power, determine a first duty cycle currently corresponding to each upper bridge arm of the motor controller and a second duty cycle currently corresponding to each lower bridge arm of the motor controller;

[0010] When it is detected that each of the bridge arms to be short-circuited is each of the upper bridge arms, taking the first duty cycle as the initial duty cycle;

[0011] Or, when it is detected that each of the bridge arms to be short-circuited is each of the lower bridge arms, the second duty cycle is used as the initial duty cycle.

[0012] In one embodiment, the step of determining the first duty cycle currently corresponding to each upper bridge arm of the motor controller and the second duty cycle currently corresponding to each lower bridge arm of the motor controller based on the real-time speed, the peak torque and the peak power includes:

[0013] Determine a linear coefficient corresponding to the duty cycle of each upper bridge arm and the rotation speed of the motor according to the peak torque and the peak power;

[0014] Determining the first duty cycle based on the linear coefficient and the real-time rotation speed;

[0015] The second duty cycle is determined based on the maximum duty cycle and the first duty cycle.

[0016] In one embodiment, the step of gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle based on a preset number of steps so that each bridge arm to be short-circuited is gradually fully short-circuited includes:

[0017] Based on the preset number of steps and the initial duty cycle, determining a real-time adjustment amount corresponding to each step change of the real-time duty cycle;

[0018] The initial duty cycle is used as an initial value of the real-time duty cycle, and the real-time adjustment amount is continuously added to the real-time duty cycle until the real-time duty cycle reaches the maximum duty cycle.

[0019] In one embodiment, when it is detected that the motor controller needs to execute the active short-circuit strategy, before the step of determining each bridge arm to be short-circuited in the motor controller and obtaining the real-time speed of the current motor, it also includes:

[0020] Detecting whether each bridge arm in the motor controller fails;

[0021] When it is detected that only a single bridge arm fails, the motor controller is controlled to execute the active short-circuit strategy.

[0022] In one embodiment, before the step of gradually adjusting the real-time duty cycle of each of the bridge arms to be short-circuited from the initial duty cycle to the maximum duty cycle based on the preset number of steps so that each of the bridge arms to be short-circuited is gradually fully short-circuited, the step further includes:

[0023] Obtaining the rated voltage of the motor;

[0024] Based on the rated voltage, the preset number of steps is determined.

[0025] In addition, to achieve the above-mentioned purpose, the present application also provides a motor controller protection device, the motor controller protection device comprising:

[0026] A state judgment module is used to determine each bridge arm to be short-circuited in the motor controller when it is detected that the motor controller needs to execute an active short-circuit strategy, and obtain the real-time speed of the current motor;

[0027] An initial parameter acquisition module, used to determine the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time rotation speed, the peak torque and the peak power of the motor;

[0028] The duty cycle adjustment module is used to gradually adjust the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle based on a preset number of steps, so that each bridge arm to be short-circuited is gradually fully short-circuited.

[0029] In addition, to achieve the above-mentioned purpose, the present application also provides a motor controller protection device, which includes: a memory, a processor, and a motor controller protection program stored in the memory and executable on the processor, and the motor controller protection program is configured to implement the steps of the motor controller protection method described above.

[0030] In addition, to achieve the above-mentioned purpose, the present application also provides a storage medium, which is a computer-readable storage medium, and a motor controller protection program is stored on the computer-readable storage medium. When the motor controller protection program is executed by the processor, the steps of the motor controller protection method described above are implemented.

[0031] In addition, to achieve the above-mentioned purpose, the present application also provides a computer program product, which includes a computer program, and when the computer program is executed by a processor, the steps of the motor controller protection method described above are implemented.

[0032] The present application provides a motor controller protection method, device, equipment, storage medium and computer program product, the steps of the motor controller protection method include: when it is detected that the motor controller needs to execute an active short-circuit strategy, determining each bridge arm to be short-circuited in the motor controller that needs to be short-circuited, and obtaining the real-time speed of the current motor; based on the real-time speed, the peak torque and peak power of the motor, determining the initial duty cycle currently corresponding to each bridge arm to be short-circuited; based on a preset number of steps, gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle, so that each bridge arm to be short-circuited is gradually fully short-circuited. When the motor controller needs to execute an active short-circuit strategy, it determines the bridge arms that need to be short-circuited and the current real-time speed of the motor, and based on the peak torque and peak power of the motor, obtains the initial duty cycle required for the bridge arms that need to be short-circuited corresponding to the current speed of the motor, and then gradually adjusts the initial duty cycle of each bridge arm to the maximum duty cycle through the corresponding preset number of steps, so that each bridge arm gradually completes the short-circuit process, thereby suppressing the peak current generated by the instantaneous switching of the on and off states of the power tube in the bridge arm, reducing the impact of the peak current on the motor controller, and extending the service life of the motor controller. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0034] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0035] Figure 1 A flowchart of the first embodiment of the motor controller protection method of the present application is provided;

[0036] Figure 2 A flow chart of the second embodiment of the motor controller protection method of the present application;

[0037] Figure 3 A flowchart diagram of the third embodiment of the motor controller protection method of the present application;

[0038] Figure 4 This is a schematic diagram of the module structure of the motor controller protection device according to an embodiment of the present application;

[0039] Figure 5 This is a schematic diagram of the structure of the motor controller protection device according to an embodiment of the present application.

[0040] The purpose, features and advantages of this application will be further described in conjunction with the embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0041] It should be understood that the specific embodiments described herein are only used to explain the technical solutions of the present application and are not used to limit the present application.

[0042] In order to better understand the technical solution of the present application, a detailed description will be given below in conjunction with the accompanying drawings and specific implementation methods.

[0043] The main solution of the present application is: when it is detected that the motor controller needs to execute an active short-circuit strategy, the bridge arms to be short-circuited in the motor controller that need to be short-circuited are determined, and the real-time speed of the current motor is obtained; based on the real-time speed, the peak torque and peak power of the motor, the initial duty cycle currently corresponding to each bridge arm to be short-circuited is determined; based on a preset number of steps, the real-time duty cycle of each bridge arm to be short-circuited is gradually adjusted from the initial duty cycle to the maximum duty cycle.

[0044] At present, motors have been popularized in every corner of people's lives, especially in some places where machines need to provide a lot of power. In order to improve power output, people have gradually adopted high-power density permanent magnet synchronous motors to replace traditional motors. In order to ensure that such high-power density motors can drive safely, it is usually required that the motor controller can shut down the motor output when a fault occurs, so that the motor torque is close to zero. However, when the motor is at high speed, if the bridge arms of the three-phase bridge are quickly closed, the motor will generate back electromotive force, which will cause the current formed by the back electromotive force generated by the motor to flow back to the battery through the freewheeling diode of the three-phase bridge, thereby generating a large braking torque. Usually, the upper bridge arms of the motor controller can be controlled to short-circuit or the lower bridge arms by active short-circuiting, thereby reducing the motor output torque. However, due to reasons such as device electrical parameters, even if this method is used, a large peak current may still be generated to impact the circuit components in the motor controller, causing damage to the motor controller or the motor. Therefore, how to reduce the peak current generated by the motor controller during active short-circuiting is a problem that needs to be solved urgently.

[0045] When the present application detects that the motor controller needs to execute an active short-circuit strategy, it determines the bridge arms that need to be short-circuited and the current real-time speed of the motor, and based on the peak torque and peak power of the motor, obtains the initial duty cycle required for the bridge arms that need to be short-circuited corresponding to the current speed of the motor, and then gradually adjusts the initial duty cycle of each bridge arm to the maximum duty cycle through the corresponding preset number of steps, so that each bridge arm gradually completes the short-circuit process, thereby suppressing the peak current generated by the instantaneous switching of the on and off states of the power tube in the bridge arm, reducing the impact of the peak current on the motor controller, and extending the service life of the motor controller.

[0046] It should be noted that the execution subject of this embodiment can be a motor controller protection device, or a motor controller protection device with data processing, network communication and program running functions, etc., and this embodiment does not specifically limit this. The following takes the motor controller protection device as the execution subject as an example to illustrate this embodiment and the following embodiments.

[0047] Based on this, the present application proposes a motor controller protection method of the first embodiment, please refer to Figure 1 , the motor controller protection method comprises steps S10-S30:

[0048] Step S10, when it is detected that the motor controller needs to execute an active short-circuit strategy, each bridge arm to be short-circuited in the motor controller is determined, and the real-time speed of the current motor is obtained;

[0049] It should be understood that the motor controller refers to a device that controls the motor speed, direction, torque and power, which is widely used in automation systems in various industries. In this embodiment, the motor controller is used to control the three-phase motor to work, which can specifically include a three-phase bridge, and is connected to the three-phase motor through the three-phase bridge, wherein each bridge arm of the three-phase bridge is provided with an IGBT tube or other power tube with similar functions, and a freewheeling diode connected in reverse parallel thereto. In theory, when the motor controller is in a working state, the working state of the three-phase bridge can be controlled according to different control requirements to accurately control the motor, and when the motor is not required to work, the bridge arms inside the three-phase bridge are switched to the off state, and the power can be stopped from being delivered to the three-phase motor, so that the three-phase motor stops working. However, when the three-phase motor is running at high speed, if the three-phase bridge is stopped directly from working, the three-phase motor will generate a large back electromotive force, and the back electromotive force will be fed to the battery through the freewheeling diode. A large braking torque is generated, and a large current impact will also be generated on the power tube in the off state in the three-phase bridge, which is easy to cause damage to the three-phase bridge. In response to the above situation, active short-circuit measurement can usually be used to control the three-phase bridge in the motor controller to short-circuit all its upper bridge arms or all its lower bridge arms, so as to short-circuit the three ports of the three-phase motor, thereby making the torque output of the three-phase motor close to zero, thereby reducing the current impact on the motor controller caused by the back electromotive force generated when the three-phase motor stops working at high speed.

[0050] It should be noted that, in actual situations, due to the characteristics of the power tubes in each arm of the three-phase bridge, a large transient voltage will be generated when the on and off states of the power tubes are switched quickly. Therefore, even if an active short-circuit strategy is adopted, it may still cause excessive peak current to impact the motor controller.

[0051] It is easy to understand that in this embodiment, when the motor is in a high-speed running state and the user needs to stop the motor to work, it can be determined that the current motor controller needs to execute an active short-circuit strategy. At this time, each group of bridge arms that need to be short-circuited and discharged in the three-phase bridge inside the motor controller can be obtained, that is, each bridge arm to be short-circuited as described above. Each group of bridge arms refers to any group of three upper bridge arms or three lower bridge arms in the three-phase bridge. The selected object can be judged according to the actual situation. If it is because one or more upper bridge arms fail, the selected object is the three lower bridge arms; if it is because one or more lower bridge arms fail, the selected object is the three upper bridge arms; if it is because the motor fails, the selected object can be either the three upper bridge arms or the three lower bridge arms, preferably the three upper bridge arms. At the same time, the angular position and angular velocity of the motor can also be measured by a rotary transformer to obtain the real-time speed of the motor.

[0052] Step S20, determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time rotation speed, the peak torque and the peak power of the motor;

[0053] It should be noted that peak torque refers to the maximum torque that the motor can output, peak power refers to the maximum power that the motor can generate, and initial duty cycle refers to the initial duty cycle corresponding to each duty cycle adjustment in the process of controlling the three short-circuited bridge arms to switch from the current state to the fully short-circuited state. The larger the duty cycle, the longer the bridge arm is turned on. When the duty cycle reaches the maximum, it can be considered that the bridge arm is in a fully turned-on state. When the three upper bridge arms or the three lower bridge arms are in a fully turned-on state at the same time, it is considered that the active short-circuit strategy has been implemented.

[0054] It is easy to understand that in this embodiment, when the motor controller implements the active short-circuit strategy, the magnitude of the reverse electromotive force generated by the motor is related to the real-time speed, peak torque and peak power of the motor, and the discharge effect of reducing the reverse electromotive force through the active short-circuit strategy is related to the conduction time of each bridge arm that executes the active short-circuit strategy, and the conduction time is related to the duty cycle of the control signal that controls each bridge arm. Therefore, through the correlation of the above parameters, through the real-time speed, peak torque and peak power, the minimum duty cycle that can prevent each short-circuited bridge arm from generating excessive reverse electromotive force and peak current during the active short-circuit strategy, that is, the above-mentioned initial duty cycle, can be calculated.

[0055] Step S30, based on a preset number of steps, gradually adjusting the real-time duty cycle of each of the bridge arms to be short-circuited from the initial duty cycle to the maximum duty cycle, so that each of the bridge arms to be short-circuited is gradually and completely short-circuited.

[0056] It should be noted that, in this embodiment, in order to prevent the speed of each bridge arm to be short-circuited from being short-circuited too quickly and generating a large peak current, that is, to prevent the power tube of the bridge arm to be short-circuited from entering the fully-on state too quickly and generating a large peak current, in the process of controlling the motor controller to execute the active short-circuit strategy, the duty cycle of the control signal for controlling each bridge arm to be short-circuited is gradually changed from the initial duty cycle described above to the maximum duty cycle. Among them, the maximum duty cycle can be considered to be 100%, that is, the duty cycle that can make the bridge arm to be short-circuited in the fully-on state.

[0057] It is worth noting that in this embodiment, the initial duty cycle can be continuously changed. In addition to the initial duty cycle at the start, the current initial duty cycle is composed of the sum of the initial duty cycle before the last adjustment and the accumulated duty cycle adjustment value.

[0058] It is easy to understand that in order to slow down the switching speed of the on-off state of the power tube of each short-circuited bridge arm, the process of switching each short-circuited bridge arm to a fully on state can be divided into several steps, and the initial duty cycle obtained above is used as the starting duty cycle corresponding to each short-circuited bridge arm, and then the initial duty cycle is accumulated step by step with a preset number of steps until the initial duty cycle rises to the maximum duty cycle, and each short-circuited bridge arm enters a fully on state. In this way, each short-circuited bridge arm will not switch to a fully on state instantly during the execution of the active short-circuit strategy, which greatly reduces the peak current generated by the instantaneous conduction of the power tube, and at the same time will not cause the motor to generate a large reverse electromotive force flowing to the battery, which can better protect the circuit inside the motor controller from being damaged by excessive instantaneous current or instantaneous voltage.

[0059] The preset number of steps is a calibration value, which is used to indicate the number of steps or times that the duty cycle needs to be changed in the process of controlling the change from the short-circuited bridge arm to the short-circuited bridge arm in the fully conductive state. It can be calibrated according to the specific electrical parameters of the motor. If the preset number of steps is set too small, it may still cause a large peak current. If the set value is too large, the response speed of stopping the motor operation is too slow, which may cause certain harm.

[0060] The present application provides a motor controller protection method, the steps of the motor controller protection method include: when it is detected that the motor controller needs to execute an active short-circuit strategy, determining each bridge arm to be short-circuited in the motor controller that needs to be short-circuited, and obtaining the real-time speed of the current motor; based on the real-time speed, the peak torque and peak power of the motor, determining the initial duty cycle currently corresponding to each bridge arm to be short-circuited; based on a preset number of steps, gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle, so that each bridge arm to be short-circuited is gradually fully short-circuited. When the motor controller needs to execute an active short-circuit strategy, it determines the bridge arms that need to be short-circuited and the current real-time speed of the motor, and based on the peak torque and peak power of the motor, obtains the initial duty cycle required for the bridge arms that need to be short-circuited corresponding to the current speed of the motor, and then gradually adjusts the initial duty cycle of each bridge arm to the maximum duty cycle through the corresponding preset number of steps, so that each bridge arm gradually completes the short-circuit process, thereby suppressing the peak current generated by the instantaneous switching of the on and off states of the power tube in the bridge arm, reducing the impact of the peak current on the motor controller, and extending the service life of the motor controller.

[0061] Based on the first embodiment of the present application, in the second embodiment of the present application, the same or similar contents as those in the above-mentioned embodiment 1 can refer to the above introduction, and will not be repeated later. Figure 2The step of determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time speed, the peak torque and the peak power of the motor comprises:

[0062] Step S21, determining a first duty cycle currently corresponding to each upper bridge arm of the motor controller and a second duty cycle currently corresponding to each lower bridge arm of the motor controller based on the real-time speed, the peak torque and the peak power;

[0063] It should be noted that, in this embodiment, different types of motors require different discharge effects at different real-time speeds. Correspondingly, when the motor controller starts to execute the active short-circuit strategy, the initial duty cycle of each short-circuited bridge arm corresponding to the demand is also different. Therefore, the linear relationship between the current motor speed and the duty cycle of each short-circuited bridge arm corresponding to the demand when the motor controller executes the active short-circuit strategy can be determined by the peak torque and peak power, so as to determine the duty cycle required in the initial stage of executing the active protection strategy by the previously acquired real-time speed. The active short-circuit strategy includes the upper bridge arm active short-circuit strategy and the lower bridge arm active short-circuit strategy, which are respectively applicable to different scenarios. If the upper bridge arm active short-circuit strategy is adopted, it is necessary to determine the first duty cycle corresponding to each upper bridge arm. If the lower bridge arm active short-circuit strategy is adopted, it is necessary to determine the second duty cycle corresponding to each lower bridge arm. Here, it is not yet determined which active short-circuit strategy needs to be adopted, so both can be calculated first, so as to facilitate selection according to the actual situation.

[0064] Step S221, when it is detected that each of the bridge arms to be short-circuited is each of the upper bridge arms, using the first duty cycle as the initial duty cycle;

[0065] Step S222, or, when it is detected that each of the bridge arms to be short-circuited is each of the lower bridge arms, the second duty cycle is used as the initial duty cycle.

[0066] It is easy to understand that in this embodiment, if the motor needs to be stopped due to a fault in the motor, both active short-circuit strategies can be used; if one or more upper bridge arms in the motor controller fail, the lower bridge arm active short-circuit strategy can be used to protect the motor controller, and the second duty cycle obtained by the above method can be used as the initial duty cycle for executing the active short-circuit strategy; if one or more lower bridge arms in the motor controller fail, the upper bridge arm active short-circuit strategy can be used to protect the motor controller, and the first duty cycle obtained by the above method can be used as the initial duty cycle for executing the active short-circuit strategy.

[0067] Further, in this embodiment, the step of determining the first duty cycle currently corresponding to each upper bridge arm of the motor controller and the second duty cycle currently corresponding to each lower bridge arm of the motor controller based on the real-time speed, the peak torque and the peak power includes:

[0068] Step S211, determining a linear coefficient corresponding to a duty cycle corresponding to each upper bridge arm and a rotation speed of the motor according to the peak torque and the peak power;

[0069] It should be noted that, in this embodiment, a linear relationship can be established between the real-time speed of the motor and the duty cycle of the active short-circuit strategy required by the corresponding motor controller. The linear relationship can be obtained by calculating the peak torque and peak power. If the peak torque is , the peak power is , then the linear coefficient in the linear relationship between the real-time speed and the first duty cycle is The expression is:

[0070] ;

[0071] Step S212, determining the first duty cycle based on the linear coefficient and the real-time rotation speed;

[0072] It is easy to understand that the first duty cycle can be directly obtained by multiplying the linear coefficient by the real-time speed. The expression is:

[0073] ;

[0074] in, is the real-time speed of the motor.

[0075] Step S213: determining the second duty cycle based on the maximum duty cycle and the first duty cycle.

[0076] It is easy to understand that, since in the same three-phase bridge, the sum of the second duty cycle and the first duty cycle should be equal to 100%, so the second duty cycle corresponding to each lower bridge arm is The expression is:

[0077] ;

[0078] Further, in this embodiment, the step of gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle based on the preset number of steps so that each bridge arm to be short-circuited is gradually fully short-circuited includes:

[0079] Step S31, determining a real-time adjustment amount corresponding to each step change of the real-time duty cycle based on the preset number of steps and the initial duty cycle;

[0080] It should be noted that, in this embodiment, in the initial stage of executing the active short-circuit strategy, the first duty cycle or the second duty cycle can be used as the initial duty cycle for the real-time duty cycle to start, and at other times, the final real-time duty cycle obtained by the last duty cycle adjustment can be used as the current initial duty cycle. Corresponding real-time adjustment amount The expression is:

[0081] ;

[0082] in, is the preset number of steps. It can be seen from the above formula that each time the real-time duty cycle is adjusted, the real-time adjustment amount will gradually increase, which can improve the efficiency of executing the active short-circuit strategy.

[0083] Step S32, taking the initial duty cycle as the initial value of the real-time duty cycle, and continuously adding the real-time adjustment amount to the real-time duty cycle until the real-time duty cycle reaches the maximum duty cycle.

[0084] It should be noted that, in this embodiment, if the real-time duty cycle The initial duty cycle is the first duty cycle , then the real-time duty cycle after the first adjustment The expression is:

[0085] ;

[0086] Correspondingly, if the real-time duty cycle The initial duty cycle is the second duty cycle , then the real-time duty cycle after the first adjustment The expression is:

[0087] ;

[0088] Based on the calculation methods of the above two cases, each subsequent real-time duty cycle can be obtained by analogy according to the above formula.

[0089] Based on the first embodiment and / or the second embodiment of the present application, in the third embodiment of the present application, the same or similar contents as those of the above-mentioned first and second embodiments can refer to the above introduction, and will not be repeated later. Figure 3, before the step of determining each bridge arm to be short-circuited in the motor controller that needs to be short-circuited when it is detected that the motor controller needs to execute the active short-circuit strategy, and obtaining the real-time speed of the current motor, it also includes:

[0090] Step S01, detecting whether each bridge arm in the motor controller fails;

[0091] Step S02, when it is detected that only a single bridge arm fails, controlling the motor controller to execute the active short-circuit strategy.

[0092] It should be noted that in this embodiment, when the current motor is in a high-speed operation state, if it is detected that one or more upper bridge arms in the motor controller have failed, and one or more lower bridge arms have failed, the motor controller can execute an active short-circuit strategy accordingly.

[0093] It is worth noting that if both the upper bridge arm and the lower bridge arm of the motor controller fail at the same time, the active short-circuit strategy cannot be executed.

[0094] Further, in this embodiment, before the step of gradually adjusting the real-time duty cycle of each of the bridge arms to be short-circuited from the initial duty cycle to the maximum duty cycle based on the preset number of steps so that each of the bridge arms to be short-circuited is gradually fully short-circuited, the method further includes:

[0095] Step S301, obtaining the rated voltage of the motor;

[0096] Step S302: determining the preset number of steps based on the rated voltage.

[0097] It is easy to understand that in this embodiment, if the rated voltage of the motor is too large when it is working, the transient voltage generated when the motor stops working will also be very large, that is, a large peak current will be generated. In order to avoid the generation of peak current, the change process of the rated voltage should be divided into several parts, which can also be understood as the need to divide the number of times the duty cycle of the control signal of the bridge arm to be short-circuited is changed into several parts, so that the voltage change amount each time becomes smaller, thereby eliminating the peak current deformation generated each time the voltage is changed. Therefore, the preset number of steps for adjusting the duty cycle of the control signal of the bridge arm to be short-circuited should be in direct proportion to the rated voltage of the motor. The larger the rated voltage of the motor, the larger the value of the preset number of steps.

[0098] The present application also provides a motor controller protection device, please refer to Figure 4 , the motor controller protection device comprises:

[0099] The state judgment module 10 is used to determine each bridge arm to be short-circuited in the motor controller when it is detected that the motor controller needs to execute an active short-circuit strategy, and obtain the real-time speed of the current motor;

[0100] An initial parameter acquisition module 20, for determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time rotation speed, the peak torque and the peak power of the motor;

[0101] The duty cycle adjustment module 30 is used to gradually adjust the real-time duty cycle of each of the bridge arms to be short-circuited from the initial duty cycle to the maximum duty cycle based on a preset number of steps, so that each of the bridge arms to be short-circuited can be gradually and completely short-circuited.

[0102] The motor controller protection device provided in the embodiment of the present application adopts the motor controller protection method in the above embodiment, which can solve the technical problem of how to reduce the peak current generated by the motor controller during the active short circuit process. Compared with the prior art, the beneficial effects of the motor controller protection device provided in the embodiment of the present application are the same as the beneficial effects of the motor controller protection method provided in the above embodiment, and other technical features in the motor controller protection device are the same as the features disclosed in the above embodiment method, which will not be repeated here.

[0103] The present application provides a motor controller protection device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the motor controller protection method in the above-mentioned embodiment one.

[0104] Reference below Figure 5 , which shows a schematic diagram of the structure of a motor controller protection device suitable for implementing the embodiment of the present application. The motor controller protection device in the embodiment of the present application may include but is not limited to a fixed terminal such as a vehicle-mounted terminal. Figure 5 The motor controller protection device shown is merely an example and should not bring any limitation to the functions and scope of use of the embodiments of the present application.

[0105] like Figure 5As shown, the motor controller protection device may include a processing device 1001 (e.g., a central processing unit, a graphics processor, etc.), which can perform various appropriate actions and processes according to a program stored in a read-only memory (ROM: Read Only Memory) 1002 or a program loaded from a storage device 1003 to a random access memory (RAM: Random Access Memory) 1004. In RAM1004, various programs and data required for the operation of the motor controller protection device are also stored. The processing device 1001, ROM1002, and RAM1004 are connected to each other through a bus 1005. An input / output (I / O) interface 1006 is also connected to the bus. Generally, the following systems can be connected to the I / O interface 1006: an input device 1007 including, for example, a touch screen, a touch pad, a keyboard, a mouse, an image sensor, a microphone, an accelerometer, a gyroscope, etc.; an output device 1008 including, for example, a liquid crystal display (LCD: Liquid Crystal Display), a speaker, a vibrator, etc.; a storage device 1003 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 1009. The communication device 1009 can allow the motor controller protection device to communicate with other devices wirelessly or by wire to exchange data. Although the figure shows a motor controller protection device with various systems, it should be understood that it is not required to implement or have all the systems shown. More or fewer systems can be implemented or have alternatively.

[0106] In particular, according to the embodiments disclosed in the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, the embodiments disclosed in the present application include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program includes a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device, or installed from a storage device 1003, or installed from a ROM 1002. When the computer program is executed by the processing device 1001, the above-mentioned functions defined in the method of the embodiment disclosed in the present application are executed.

[0107] The motor controller protection device provided by the present application adopts the motor controller protection method in the above embodiment, which can solve the technical problem of how to reduce the peak current generated by the motor controller during the active short circuit process. Compared with the prior art, the beneficial effects of the motor controller protection device provided by the present application are the same as the beneficial effects of the motor controller protection method provided by the above embodiment, and the other technical features in the motor controller protection device are the same as the features disclosed in the method of the previous embodiment, which will not be repeated here.

[0108] It should be understood that the various parts disclosed in this application can be implemented by hardware, software, firmware or a combination thereof. In the description of the above embodiments, specific features, structures, materials or characteristics can be combined in any one or more embodiments or examples in a suitable manner.

[0109] The above is only a specific implementation of the present application, but the protection scope of the present application is not limited thereto. Any person skilled in the art who is familiar with the present technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

[0110] The present application provides a computer-readable storage medium having computer-readable program instructions (ie, computer programs) stored thereon, and the computer-readable program instructions are used to execute the motor controller protection method in the above-mentioned embodiment.

[0111] The computer-readable storage medium provided in the present application may be, for example, a USB flash drive, but is not limited to electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, systems or devices, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM: Random Access Memory), a read-only memory (ROM: Read Only Memory), an erasable programmable read-only memory (EPROM: Erasable Programmable Read Only Memory or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM: CD-Read Only Memory), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program, which may be used by or in combination with an instruction execution system, system or device. The program code contained on the computer-readable storage medium may be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (Radio Frequency: Radio Frequency), etc., or any suitable combination of the above.

[0112] The computer-readable storage medium may be included in the motor controller protection device; or may exist independently without being assembled into the motor controller protection device.

[0113] The above-mentioned computer-readable storage medium carries one or more programs. When the above-mentioned one or more programs are executed by the motor controller protection device, the motor controller protection device: when it is detected that the motor controller needs to execute an active short-circuit strategy, determines each bridge arm to be short-circuited in the motor controller that needs to be short-circuited, and obtains the real-time speed of the current motor; based on the real-time speed, the peak torque and peak power of the motor, determines the initial duty cycle currently corresponding to each bridge arm to be short-circuited; based on a preset number of steps, gradually adjusts the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle, so that each bridge arm to be short-circuited is gradually fully short-circuited.

[0114] Computer program code for performing the operations of the present application may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0115] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present application. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs a specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0116] The modules involved in the embodiments described in this application may be implemented by software or hardware, wherein the name of the module does not constitute a limitation on the unit itself in some cases.

[0117] The readable storage medium provided in the present application is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer programs) for executing the above-mentioned motor controller protection method, and can solve the technical problem of how to reduce the peak current generated by the motor controller during the active short circuit process. Compared with the prior art, the beneficial effects of the computer-readable storage medium provided in the present application are the same as the beneficial effects of the motor controller protection method provided in the above-mentioned embodiment, and will not be repeated here.

[0118] The present application also provides a computer program product, including a computer program, which implements the steps of the motor controller protection method as described above when the computer program is executed by a processor.

[0119] The computer program product provided by the present application can solve the technical problem of how to reduce the peak current generated by the motor controller during the active short circuit process. Compared with the prior art, the beneficial effects of the computer program product provided by the present application are the same as the beneficial effects of the motor controller protection method provided by the above embodiment, which will not be repeated here.

[0120] The above are only preferred embodiments of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent processing scope of the present application.

Claims

1. A motor controller protection method, characterized in that: The steps of the motor controller protection method include: When it is detected that the motor controller needs to execute an active short-circuit strategy, each bridge arm to be short-circuited in the motor controller is determined, and the real-time speed of the current motor is obtained; Based on the real-time rotation speed, the peak torque and the peak power of the motor, determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited; Based on a preset number of steps, the real-time duty cycle of each of the bridge arms to be short-circuited is gradually adjusted from the initial duty cycle to the maximum duty cycle, so that each of the bridge arms to be short-circuited is gradually fully short-circuited; The step of determining the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time rotation speed, the peak torque and the peak power of the motor comprises: Based on the real-time rotation speed, the peak torque and the peak power, determine a first duty cycle currently corresponding to each upper bridge arm of the motor controller and a second duty cycle currently corresponding to each lower bridge arm of the motor controller; When it is detected that each of the bridge arms to be short-circuited is each of the upper bridge arms, taking the first duty cycle as the initial duty cycle; Or, when it is detected that each of the bridge arms to be short-circuited is each of the lower bridge arms, the second duty cycle is used as the initial duty cycle; The step of determining the first duty cycle currently corresponding to each upper bridge arm of the motor controller and the second duty cycle currently corresponding to each lower bridge arm of the motor controller based on the real-time speed, the peak torque and the peak power comprises: Determine a linear coefficient corresponding to the duty cycle of each upper bridge arm and the rotation speed of the motor according to the peak torque and the peak power; Determining the first duty cycle based on the linear coefficient and the real-time rotation speed; The second duty cycle is determined based on the maximum duty cycle and the first duty cycle.

2. The motor controller protection method according to claim 1, characterized in that: The step of gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle based on the preset number of steps so that each bridge arm to be short-circuited is gradually fully short-circuited comprises: Based on the preset number of steps and the initial duty cycle, determining a real-time adjustment amount corresponding to each step change of the real-time duty cycle; The initial duty cycle is used as an initial value of the real-time duty cycle, and the real-time adjustment amount is continuously added to the real-time duty cycle until the real-time duty cycle reaches the maximum duty cycle.

3. The motor controller protection method according to claim 1, characterized in that: Before the step of determining each bridge arm to be short-circuited in the motor controller that needs to be short-circuited when it is detected that the motor controller needs to execute the active short-circuit strategy and obtaining the real-time speed of the current motor, the method further includes: Detecting whether each bridge arm in the motor controller fails; When it is detected that only a single bridge arm fails, the motor controller is controlled to execute the active short-circuit strategy.

4. The motor controller protection method according to claim 1, characterized in that: Before the step of gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle based on the preset number of steps so that each bridge arm to be short-circuited is gradually fully short-circuited, the method further includes: Obtaining the rated voltage of the motor; Based on the rated voltage, the preset number of steps is determined.

5. A motor controller protection device, characterized in that: The motor controller protection device comprises: A state judgment module is used to determine each bridge arm to be short-circuited in the motor controller when it is detected that the motor controller needs to execute an active short-circuit strategy, and obtain the real-time speed of the current motor; An initial parameter acquisition module, used to determine the initial duty cycle currently corresponding to each of the bridge arms to be short-circuited based on the real-time rotation speed, the peak torque and the peak power of the motor; A duty cycle adjustment module, used for gradually adjusting the real-time duty cycle of each bridge arm to be short-circuited from the initial duty cycle to the maximum duty cycle based on a preset number of steps, so that each bridge arm to be short-circuited is gradually fully short-circuited; The initial parameter acquisition module is further used to determine the first duty cycle currently corresponding to each upper bridge arm of the motor controller and the second duty cycle currently corresponding to each lower bridge arm of the motor controller based on the real-time speed, the peak torque and the peak power; The initial parameter acquisition module is further configured to use the first duty cycle as the initial duty cycle when it is detected that each of the bridge arms to be short-circuited is each of the upper bridge arms; The initial parameter acquisition module is further configured to use the second duty cycle as the initial duty cycle when it is detected that each of the bridge arms to be short-circuited is each of the lower bridge arms; The initial parameter acquisition module is further used to determine the linear coefficient between the duty cycle corresponding to each upper bridge arm and the rotation speed of the motor according to the peak torque and the peak power; The initial parameter acquisition module is further used to determine the first duty cycle based on the linear coefficient and the real-time rotation speed; The initial parameter acquisition module is further used to determine the second duty cycle based on the maximum duty cycle and the first duty cycle.

6. A motor controller protection device, characterized in that: The motor controller protection device comprises: a memory, a processor, and a motor controller protection program stored in the memory and executable on the processor, wherein the motor controller protection program is configured to implement the steps of the motor controller protection method according to any one of claims 1 to 4.

7. A storage medium, characterized in that: The storage medium is a computer-readable storage medium, on which a motor controller protection program is stored. When the motor controller protection program is executed by a processor, the steps of the motor controller protection method according to any one of claims 1 to 4 are implemented.

8. A computer program product, characterized in that The computer program product comprises a computer program, and when the computer program is executed by a processor, the steps of the motor controller protection method according to any one of claims 1 to 4 are implemented.

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