Servo motor dynamic braking method, system, intelligent power module and storage medium

Abstract

This application relates to the technical field of servo motor control, and provides a dynamic braking method, system, intelligent power module, and storage medium for a servo motor. When the intelligent power module detects a fault signal, it outputs pulse width modulation (PWM) signals in stages, with the duty cycle increasing, to control the three lower-bridge circuits of the servo motor to perform chopping operations, thereby releasing residual electrical energy in the circuits step by step and rapidly. While controlling the three lower-bridge circuits to execute the chopping operation of the PWM signal in the final stage, the intelligent power module simultaneously performs current detection during the chopping process to determine whether the residual electrical energy has been completely released. When the intelligent power module determines that the residual electrical energy has been completely released, it outputs a PWM signal with a preset duty cycle to control the three lower-bridge circuits to suppress the rotation of the servo motor rotor. This application achieves dynamic braking of the servo motor by executing the residual electrical energy release stage and the rotor rotation suppression stage through the intelligent power module.

Description

Technical Field

[0001] This application relates to the technical field of servo motor control, and in particular to a servo motor dynamic braking method, system, intelligent power module, and storage medium. Background Technology

[0002] In the production and R&D process, there may be emergencies requiring rapid shutdown, demanding that servo motors used in production and R&D possess excellent braking performance. Existing technology uses switching components (e.g., relays) to directly disconnect the drive power supply to achieve servo motor braking. However, this direct power-off control method does not solve the problem of releasing a large amount of electrical energy in the motor circuit. This problem results in a large amount of electrical energy being released through the components in the circuit, leading to damage to the intelligent power module in the servo motor control circuit and reducing the lifespan of the servo motor. Summary of the Invention

[0003] In view of this, this application provides a servo motor dynamic braking method, system, intelligent power module and storage medium to solve the technical problems of residual electrical energy release and rotor braking control during the servo motor braking process.

[0004] A first aspect of this application provides a dynamic braking method for a servo motor, the method comprising:

[0005] When a fault signal is detected, the three lower-bridge circuits are controlled to execute multiple stages of pulse width modulation (PWM) signal chopping in order of increasing duty cycle to control the servo motor's control circuit to release residual power step by step. During the chopping of each stage of the PWM signal, the current of the three lower-bridge circuits is less than a preset safe current. When the three lower-bridge circuits are controlled to execute the chopping of the last stage of the PWM signal, the current of the servo motor's control circuit is acquired every preset chopping time interval.

[0006] The residual electrical energy is determined based on the current during the preset chopping time period to determine whether it has been completely released.

[0007] When the residual energy is completely released based on the current during the preset chopping time period, a PWM signal with a preset duty cycle is output to control the three-way downbridge circuit to brake the servo motor.

[0008] In an optional implementation, when a fault signal is detected, the method further includes:

[0009] The intelligent power module is automatically shut down, and the three-way bridge circuit is controlled to shut down its output.

[0010] After a preset switching delay, the intelligent power module automatically restarts.

[0011] In an optional implementation, the step of outputting a PWM signal with a preset duty cycle to control the three lower bridge circuits to perform the braking action of the servo motor includes:

[0012] Output a PWM signal with a 100% duty cycle to control the three lower bridge circuits to suppress the rotation of the servo motor, and output an activation signal to the speed detection module;

[0013] The rotational speed of the servo motor is controlled by the rotational speed detection module.

[0014] When the servo motor's speed is 0 rpm, the output to the three-way downbridge circuit is zero.

[0015] In an optional implementation, the control of the three lower bridge circuits to perform multiple stages of pulse width modulation (PWM) signal chopping in ascending order of duty cycle includes:

[0016] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in a preset first duty cycle for a preset first time period in the first stage.

[0017] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the second stage with a preset second duty cycle for a preset second time period;

[0018] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the third stage with a preset third duty cycle during the preset second time period;

[0019] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the fourth stage with a preset fourth duty cycle during the preset second time period;

[0020] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fifth stage with a preset fifth duty cycle for the preset second time period;

[0021] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the sixth stage with a preset sixth duty cycle for the preset second time period;

[0022] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the seventh stage with a preset seventh duty cycle for the preset second time period;

[0023] The three lower bridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the eighth stage with a preset eighth duty cycle for a preset third time period;

[0024] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the ninth stage with a preset ninth duty cycle for the preset second time period;

[0025] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the tenth stage with a preset tenth duty cycle for the preset third time period;

[0026] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the eleventh stage with a preset eleventh duty cycle for the preset second time period;

[0027] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the twelfth stage with a preset twelfth duty cycle during the preset third time period;

[0028] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the thirteenth stage with a preset thirteenth duty cycle during the preset second time period;

[0029] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fourteenth stage with a preset fourteenth duty cycle during the preset third time period;

[0030] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fifteenth stage with a preset fifteenth duty cycle for the preset first time period;

[0031] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the sixteenth stage with a preset sixteenth duty cycle during the preset third time period;

[0032] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the seventeenth stage with a preset seventeenth duty cycle for the preset first time period;

[0033] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the eighteenth stage with a preset eighteenth duty cycle for the preset third time period;

[0034] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the nineteenth stage with a preset nineteenth duty cycle for the preset first time period;

[0035] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the twentieth stage with a preset twentieth duty cycle for the preset first time period;

[0036] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 21st stage with a preset 21st duty cycle for the preset first time period;

[0037] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the preset first time period with a preset 22nd duty cycle in the 22nd stage.

[0038] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 23rd stage with a preset 23rd duty cycle for a preset fourth time period.

[0039] In an optional implementation, determining whether the residual energy has been completely released based on the current during the preset chopping time period includes:

[0040] The current during the preset chopping time period is compared with a preset current threshold range;

[0041] When the current during the preset chopping time period is within the current threshold range, it is determined that the residual electrical energy has been completely released.

[0042] If the current during the preset chopping time period is not entirely within the current threshold range, it is determined that the residual electrical energy has not been fully released.

[0043] In an optional implementation, the method further includes:

[0044] When it is determined that the remaining electrical energy has not been completely released, the three lower bridge circuits continue to be controlled to perform the chopping action of the PWM signal in the last stage until the remaining electrical energy is completely released.

[0045] In an optional implementation, the chopping action of the PWM signal in the final stage of controlling the three lower bridge circuits further includes:

[0046] Output activation signal to current detection module;

[0047] The current detection module is controlled to detect the current of the control circuit of the servo motor.

[0048] A second aspect of this application provides a servo motor dynamic braking system, the system comprising an intelligent power module, a speed detection module, and a current detection module, wherein the intelligent power module is used to implement the steps of the servo motor dynamic braking method.

[0049] A third aspect of this application provides an intelligent power module, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the servo motor dynamic braking method.

[0050] The fourth aspect of this application provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the servo motor dynamic braking method.

[0051] The servo motor dynamic braking method, system, intelligent power module, and storage medium provided in this application embodiment, when the intelligent power module detects a fault signal, outputs pulse width modulation (PWM) signals in stages according to an increasing duty cycle to control the three lower-bridge circuits of the servo motor to perform chopping operations, thereby releasing residual electrical energy in the circuits step by step and rapidly. While controlling the three lower-bridge circuits to execute the chopping operation of the PWM signal in the last stage, the intelligent power module simultaneously performs current detection during the chopping process to determine whether the residual electrical energy has been completely released. When the intelligent power module determines that the residual electrical energy has been completely released, it outputs a PWM signal with a preset duty cycle to control the three lower-bridge circuits to suppress the rotation of the servo motor rotor. This application achieves dynamic braking of the servo motor by executing the residual electrical energy release stage and the rotor rotation suppression stage through the intelligent power module. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a hardware architecture diagram of the servo motor dynamic braking system provided in the embodiments of this application;

[0054] Figure 2 This is a flowchart of the servo motor dynamic braking method provided in the embodiments of this application;

[0055] Figure 3 This is an oscilloscope waveform diagram of the three-phase current transformation during the braking process of the servo motor provided in this application embodiment;

[0056] Figure 4 This is a schematic diagram of the structure of the intelligent power module provided in the embodiment of this application.

[0057] Explanation of icon numbers

[0058] 1. Servo motor dynamic braking system; 11. Current detection module; 12. Speed ​​detection module; 13. Intelligent power module; 131. Processor; 132. Memory; 133. Communication bus. Detailed Implementation

[0059] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0060] Figure 1 This is a hardware architecture diagram of the servo motor dynamic braking system provided in the embodiments of this application.

[0061] The servo motor dynamic braking system 1 includes, but is not limited to, an intelligent power module 13, a speed detection module 12, and a current detection module 11.

[0062] The speed detection module 12 receives signals from the intelligent power module and detects the rotational speed of the rotor of the servo motor, feeding back the speed to the intelligent power module to achieve feedback control of the servo motor. In one optional embodiment, the speed detection module 12 is a Hall sensor built into the servo motor. The Hall sensor obtains the rotational speed of the servo motor by counting and measuring the time of pulse signals. In another optional embodiment, the servo motor can also use an encoder to read the output pulse signal to calculate the rotational speed, or use a voltage detector to measure the back electromotive force voltage to calculate the rotational speed.

[0063] The current detection module 11 is used to receive signals from the intelligent power module and detect the current of the servo motor's control circuit, and feeds back the current to the intelligent power module for monitoring the release of residual electrical energy during braking. In one optional embodiment, the current detection module 11 is part of the servo motor control circuit (e.g., a circuit with current detection function in the servo motor controller or driver). In another optional embodiment, an additionally connected current sensor can be used to obtain the current of the servo motor's control circuit.

[0064] The intelligent power module 13 is a module that integrates power electronic devices and intelligent control functions. It can output pulse width modulation (PWM) signals according to the preset duty cycle and control time to control the three lower bridge circuits in the servo motor to perform chopping and braking actions.

[0065] During servo motor operation, emergency braking may be required due to malfunctions. Conventional power-off measures leave a significant amount of residual electrical energy in the inductive components of the servo motor circuit (e.g., capacitors, inductors, transformers) that urgently needs to be released. If left uncontrolled, this residual energy will generate a high current in the circuit within a short period, causing irreversible damage to the components due to overcurrent and shortening the servo motor's lifespan. Simply cutting off the power is insufficient to meet the braking requirements of rapidly stopping the motor during emergency braking.

[0066] In this embodiment, the intelligent power module outputs PWM signals with different duty cycles at different stages to control the control circuit of the servo motor, thereby realizing dynamic braking of the servo motor. The braking process is divided into a residual energy release stage and a rotor rotation suppression stage.

[0067] See Figure 2 The diagram shows a flowchart of a servo motor dynamic braking method provided in an embodiment of this application. The servo motor dynamic braking method provided in this embodiment includes the following steps.

[0068] S21: When a fault signal is detected, the three lower bridge circuits are controlled to execute multiple stages of pulse width modulation (PWM) signal chopping in order of duty cycle from small to large, so as to control the servo motor control circuit to release the residual power step by step.

[0069] During the chopping action of the PWM signal at each stage, the current in the three lower-bridge circuits is less than the safe current of the servo motor. The current in the three lower-bridge circuits can be controlled by modulating the PWM signal. If the current in the three lower-bridge circuits exceeds the safe current of the servo motor, there is a risk of damage to the servo motor's control circuit. For example, the hardware requirement in the servo motor's control circuit is that the current through this circuit must not exceed 9A, i.e., the safe current is 9A. When the intelligent power module outputs a PWM signal to control the three lower-bridge circuits to release residual electrical energy, such as... Figure 3 The current waveforms of the three-phase circuits in the servo motor circuit shown are all within the range of [-9A, 9A]. The intelligent power module outputs PWM signals in ascending order of duty cycle to generate pulse-shaped current or voltage signals to control the residual energy to be gradually released through the three-way lower bridge circuit, achieving the effect of rapidly releasing residual energy within the circuit hardware's tolerance range of the servo motor.

[0070] In an optional implementation, to achieve better and safer chopping performance, the method of this application further includes the following when a fault signal is detected:

[0071] The intelligent power module is automatically shut down, and the three-way bridge circuit is controlled to shut down its output.

[0072] After a preset switching delay, the intelligent power module will automatically restart.

[0073] Under normal operating conditions, both the three-channel bridge circuit and the three-channel down-bridge circuit of a servo motor will perform chopping. Based on the hardware characteristics and connection relationships of the three-channel bridge circuit and the three-channel down-bridge circuit in a servo motor, it is safer to disable the output of the three-channel bridge circuit and only perform the chopping operation of the three-channel down-bridge circuit. That is, the output of the three-channel bridge circuit must be disabled before using the three-channel down-bridge circuit for chopping.

[0074] While controlling the three-way bridge circuit to shut down the output, the intelligent power module performs a mode switching process through shutdown-delay-restart to smoothly transition from the servo motor rotation control mode to the residual power output control mode. Simultaneously, the delay process ensures that the circuit and related equipment do not experience abnormalities (e.g., voltage spikes, current surges, etc.).

[0075] To expedite the braking of the servo motor, the delay time should be set as short as possible while still allowing the intelligent power control module to switch modes. For example, the intelligent power module is set to require 2.5ms for mode switching, with a preset switching time of 3ms. This satisfies the time required for the intelligent module to switch modes while minimizing the braking time of the servo motor.

[0076] The PWM signal is preset based on the linear relationship between the current and the PWM signal obtained from braking experiments of the servo motor. During braking experiments on a high-power servo motor, it was found that the intelligent power module can completely release residual electrical energy by outputting PWM signals in 23 stages, with the shortest time consumption. The servo motor used in this embodiment is a high-power servo motor, thus it is backward compatible with most servo motors with lower power than this high-power servo motor.

[0077] In an optional implementation, the control of the three lower bridge circuits to perform multiple stages of pulse width modulation (PWM) signal chopping in ascending order of duty cycle includes:

[0078] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in a preset first duty cycle for a preset first time period in the first stage.

[0079] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the second stage with a preset second duty cycle for a preset second time period;

[0080] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the third stage with a preset third duty cycle during the preset second time period;

[0081] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the fourth stage with a preset fourth duty cycle during the preset second time period;

[0082] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fifth stage with a preset fifth duty cycle for the preset second time period;

[0083] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the sixth stage with a preset sixth duty cycle for the preset second time period;

[0084] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the seventh stage with a preset seventh duty cycle for the preset second time period;

[0085] The three lower bridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the eighth stage with a preset eighth duty cycle for a preset third time period;

[0086] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the ninth stage with a preset ninth duty cycle for the preset second time period;

[0087] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the tenth stage with a preset tenth duty cycle for the preset third time period;

[0088] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the eleventh stage with a preset eleventh duty cycle for the preset second time period;

[0089] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the twelfth stage with a preset twelfth duty cycle during the preset third time period;

[0090] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the thirteenth stage with a preset thirteenth duty cycle during the preset second time period;

[0091] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fourteenth stage with a preset fourteenth duty cycle during the preset third time period;

[0092] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fifteenth stage with a preset fifteenth duty cycle for the preset first time period;

[0093] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the sixteenth stage with a preset sixteenth duty cycle during the preset third time period;

[0094] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the seventeenth stage with a preset seventeenth duty cycle for the preset first time period;

[0095] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the eighteenth stage with a preset eighteenth duty cycle for the preset third time period;

[0096] The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the nineteenth stage with a preset nineteenth duty cycle for the preset first time period;

[0097] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the twentieth stage with a preset twentieth duty cycle for the preset first time period;

[0098] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 21st stage with a preset 21st duty cycle for the preset first time period;

[0099] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the preset first time period with a preset 22nd duty cycle in the 22nd stage.

[0100] The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 23rd stage with a preset 23rd duty cycle for a preset fourth time period.

[0101] like Figure 3 As described above, during the residual energy release phase, each PWM signal output by the intelligent power module causes a change in the three-phase current waveform during servo motor braking. That is, each three-phase current waveform corresponds to a phase in which the intelligent power module controls the three lower-bridge circuits to brake the servo motor. The intelligent power module outputs PWM signals in ascending duty cycle order, ensuring that each phase releases residual energy to the maximum extent possible within the tolerance range of the servo motor circuit components, while remaining within safe current limits. For example, when the intelligent power module outputs a PWM signal with a 40% duty cycle in the first phase, the peak value of the three-phase current waveform of the servo motor is close to the safe current of the servo motor. This achieves maximum release of residual energy within the tolerance range of the circuit components.

[0102] For example, the intelligent power module can set the PWM signal according to the information shown in Table 1 below. When the intelligent power module outputs the PWM signal according to the time and duty cycle in the table, the servo motor can simultaneously meet the three requirements of short braking time, fast release, and the current during the chopping process being within a safe range.

[0103] Table 1. Duty cycle and chopping time of pulse width modulation (PWM) signals at different stages

[0104] Braking phase Duty cycle (%) Chopping time (ms) Phase 1 40 20 Phase 2 43 30 Phase 3 45 30 Phase 4 48 30 Phase 5 50 30 Phase 6 53 30 Phase 7 55 30 Phase 8 58 40 Phase 9 60 30 Phase 10 62 40 Phase 11 65 30 Phase 12 68 40 Phase 13 70 30 Phase 14 72 40 Phase 15 75 20 Phase 16 77 40 Phase 17 80 20 Phase 18 82 40 Phase 19 85 20 Phase 20 87 20 Phase 21 90 20 Phase 22 92 20 Phase 23 95 100

[0105] S22: When controlling the three lower bridge circuits to execute the chopping action of the PWM signal in the last stage, the current of the control circuit of the servo motor is obtained every preset chopping time period.

[0106] To achieve better braking performance, the release of residual electrical energy needs to be monitored before suppressing rotor rotation to ensure that the residual electrical energy is completely released. For example... Figure 3 As shown, after the first 22 chopping stages, the residual electrical energy in the circuit is within the tolerance range of the circuit components. To ensure that the residual electrical energy is completely released, the preset chopping duration of the 23rd stage can be extended to ensure sufficient time for the release of the residual electrical energy. In addition to releasing the residual electrical energy, this chopping stage also requires monitoring the electrical signals (e.g., current magnitude) of the circuit during the release process to determine the status of the released residual electrical energy.

[0107] In an optional implementation, the chopping action of the PWM signal in the final stage of controlling the three lower bridge circuits further includes:

[0108] Output activation signal to current detection module;

[0109] The current detection module is controlled to detect the current of the control circuit of the servo motor.

[0110] The intelligent power module sends an activation signal to wake up the current detection module to detect the current of the servo motor's control circuit during this stage. This allows the module to obtain the current of the servo motor's control circuit and determine whether the remaining electrical energy has been completely released based on this current reading.

[0111] S23: Determine whether the residual electrical energy has been completely released based on the current during the preset chopping time period.

[0112] like Figure 3As shown, the residual electrical energy in the servo motor causes power drift during the release process, resulting in fluctuations in the circuit current. Therefore, the intelligent power module obtains the current of the three lower bridge circuits during the entire chopping process in the final stage through the current detection module, and compares it with the preset current threshold range to reduce the error caused by current noise resulting from the decrease in residual electrical energy during release.

[0113] In an optional implementation, determining whether the residual energy has been completely released based on the current during the preset chopping time period includes:

[0114] The current during the preset chopping time period is compared with a preset current threshold range;

[0115] When the current during the preset chopping time period is within the current threshold range, it is determined that the residual electrical energy has been completely released.

[0116] If the current during the preset chopping time period is not entirely within the current threshold range, it is determined that the residual electrical energy has not been fully released.

[0117] The preset chopping time period is the preset fourth time period.

[0118] For example, in the final stage, the intelligent power module outputs a PWM signal with a 95% duty cycle to control the three lower-bridge circuits to perform a 100ms chopping action, with a preset current threshold range of (0A, 0.5A). Simultaneously with outputting the PWM signal to the three lower-bridge circuits, the intelligent power module also outputs an activation signal to the current detection module to control the current detection module to detect the current in the three lower-bridge circuits. When the detected current is within the range of (0A, 0.5A), the intelligent power module confirms that the residual energy has been completely released and enters the rotor rotation suppression stage; when the detected current is not completely within the range of (0A, 0.5A), the intelligent power module confirms that the residual energy has not been completely released, and continues to control the three lower-bridge circuits to execute the chopping action of the PWM signal in the final stage until the residual energy is completely released.

[0119] To ensure that the residual energy is fully released and to avoid prolonging the braking time of the servo motor, the intelligent power module outputs a PWM signal with a 95% duty cycle to control the three lower bridge circuits to perform a 100ms chopping action when it confirms that the residual energy has not been fully released. This allows the release of the residual energy to continue. During the release of the residual energy, the current in the three lower bridge circuits is detected to determine the release status of the residual energy in a timely manner, so as to enter the rotor rotation suppression stage as soon as possible.

[0120] S24: When the residual energy is completely released based on the current during the preset chopping time period, a PWM signal with a preset duty cycle is output to control the three lower bridge circuits to brake the servo motor.

[0121] To achieve rapid servo motor shutdown, after the residual electrical energy is fully released, the intelligent power module outputs a preset high duty cycle PWM signal for rotor suppression control. The intelligent power module controls three lower-bridge circuits to generate a reverse magnetic field in the servo motor stator, thereby suppressing the forward motion of the rotor due to inertia.

[0122] In an optional implementation, the step of outputting a PWM signal with a preset duty cycle to control the three lower bridge circuits to perform the braking action of the servo motor includes:

[0123] Output a PWM signal with a 100% duty cycle to control the three lower bridge circuits to suppress the rotation of the servo motor, and output an activation signal to the speed detection module;

[0124] The rotational speed of the servo motor is controlled by the rotational speed detection module.

[0125] When the servo motor's speed is 0 rpm, the output to the three-way downbridge circuit is zero.

[0126] The servo motor is originally running at high speed. To achieve an emergency stop (dynamic braking), a large amount of energy must be released. If this energy is not released, a significant amount will pass through the intelligent power module, potentially damaging components in the servo motor's control circuit. To quickly stop the servo motor's rotor, the intelligent power module outputs a PWM signal with a 100% duty cycle, thus suppressing rotor rotation in the shortest possible time to achieve the fastest braking effect for the servo motor. Simultaneously, the intelligent power module uses a speed detection module to detect the rotor speed and implement feedback control. The PWM signal output is quickly stopped the moment the rotor stops rotating to prevent the rotor from rotating in the opposite direction due to the intelligent power module.

[0127] When the three-channel down-bridge circuit is at a high level, the servo motor stops, first releasing energy, then stopping, and then the PWM signal output is turned off. When the three-channel down-bridge circuit changes from a high level to a low level, the PWM signal is turned off.

[0128] This embodiment of the application achieves dynamic braking of the servo motor by executing a residual energy release stage and a rotor rotation suppression stage through an intelligent power module. In the residual energy release stage, the intelligent power module controls three downstream circuits to execute multiple stages of pulse width modulation (PWM) signal chopping in ascending order of duty cycle, thereby controlling the servo motor's control circuit to release residual energy step by step. During each stage of PWM signal chopping, the current of the three downstream circuits is less than a preset safe current. When controlling the three downstream circuits to execute the final stage of PWM signal chopping, the current of the servo motor's control circuit is acquired every preset chopping time interval, thereby determining whether the residual energy has been completely released based on the current during the preset chopping time interval. When it is determined that the residual energy has been completely released based on the current during the preset chopping time interval, the rotor rotation suppression stage begins. In the rotor rotation suppression stage, the intelligent power module outputs a PWM signal with a preset duty cycle to control the three downstream circuits to brake the servo motor. That is, when the intelligent power module of this application detects a fault signal, it first releases energy, then stops the rotation of the servo motor, and finally shuts off the output PWM signal.

[0129] See Figure 4 The diagram shown is a structural schematic of the intelligent power module provided in an embodiment of this application. In a preferred embodiment of the present invention, the intelligent power module 13 may include, but is not limited to, a memory 132, at least one processor 131, and at least one communication bus 133.

[0130] Those skilled in the art should understand that Figure 4 The structure of the intelligent power module 13 shown does not constitute a limitation of the embodiments of the present invention. The intelligent power module 13 may also include more or fewer other hardware or software than shown, or different component arrangements.

[0131] In some embodiments, the intelligent power module 13 is a device capable of automatically performing numerical calculations and / or information processing according to pre-set or stored instructions, and its hardware includes, but is not limited to, microprocessors, application-specific integrated circuits, programmable gate arrays, digital processors 131, and embedded devices.

[0132] It should be noted that the intelligent power module 13 is only an example. Other existing or future electronic products that are suitable for this application should also be included within the scope of protection of this application and are incorporated herein by reference.

[0133] In some embodiments, the memory 132 stores a computer program that, when executed by the at least one processor 131, implements all or part of the steps in the servo motor dynamic braking method described above. The memory 132 includes a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), a one-time programmable read-only memory (OTPROM), an electronically erasable programmable read-only memory (EEPROM), a compact disc read-only memory (CD-ROM) or other optical disc storage, disk storage, magnetic tape storage, or any other computer-readable medium capable of carrying or storing data. Further, the computer-readable storage medium may primarily include a program storage area and a data storage area, wherein the program storage area may store an operating system, at least one application program required for a function, etc.

[0134] In some embodiments, the at least one processor 131 is the control unit of the intelligent power module 13, connecting various components of the intelligent power module 13 via various interfaces and lines. It executes programs or modules stored in the memory 132 and calls data stored in the memory 132 to perform various functions and process data of the intelligent power module 13. For example, when the at least one processor 131 executes the computer program stored in the memory 132, it implements all or part of the steps of the servo motor dynamic braking method described in this application embodiment; or it implements all or part of the functions of the servo motor dynamic braking system 1. The at least one processor 131 may be composed of integrated circuits, such as a single-packaged integrated circuit or multiple integrated circuits with the same or different functions, including combinations of one or more central processing units (CPUs), microprocessors, digital processing chips, graphics processors, and various control chips.

[0135] In some embodiments, the at least one communication bus 133 is configured to enable communication between the memory 132 and the at least one processor 131, etc. Although not shown, the intelligent power module 13 may also include a power supply (e.g., a battery) to power the various components. Preferably, the power supply can be logically connected to the at least one processor 131 via a power management device, thereby enabling functions such as charging, discharging, and power consumption management. The power supply may also include one or more DC or AC power supplies, recharging devices, power fault detection circuits, power converters or inverters, power status indicators, and other arbitrary components. The intelligent power module 13 may also include various sensors, Bluetooth modules, Wi-Fi modules, etc., which will not be described in detail here.

[0136] The integrated unit implemented as a software functional module described above can be stored in a computer-readable storage medium. This software functional module, stored in a storage medium, includes several instructions to cause an electronic device (which may be a personal computer, electronic device, or network device, etc.) or processor to execute portions of the methods described in the various embodiments of this application.

[0137] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of modules is only a logical functional division, and other division methods may be used in actual implementation.

[0138] The modules described as separate components may or may not be physically separate. The components shown as modules may or may not be physical units; they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0139] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A dynamic braking method for a servo motor, applied in an intelligent power module, characterized in that, The method includes: When a fault signal is detected, the three lower bridge circuits are controlled to execute multiple stages of pulse width modulation (PWM) signal chopping in order of increasing duty cycle to control the servo motor's control circuit to release residual power step by step. During the execution of each stage of PWM signal chopping, the current of the three lower bridge circuits is less than the preset safe current. When controlling the three lower bridge circuits to execute the chopping action of the PWM signal in the last stage, the current of the control circuit of the servo motor is obtained every preset chopping time period. The residual electrical energy is determined based on the current during the preset chopping time period to determine whether it has been completely released. When the residual energy is completely released based on the current during the preset chopping time period, a PWM signal with a preset duty cycle is output to control the three-way downbridge circuit to brake the servo motor.

2. The servo motor dynamic braking method according to claim 1, characterized in that, When a fault signal is detected, the method further includes: The intelligent power module is automatically shut down, and the three-way bridge circuit is controlled to shut down its output. After a preset switching delay, the intelligent power module automatically restarts.

3. The servo motor dynamic braking method according to claim 2, characterized in that, The output of a PWM signal with a preset duty cycle to control the three lower bridge circuits to perform the braking action of the servo motor includes: Output a PWM signal with a 100% duty cycle to control the three lower bridge circuits to suppress the rotation of the servo motor, and output an activation signal to the speed detection module; The rotational speed of the servo motor is controlled by the rotational speed detection module. When the servo motor's speed is 0 rpm, the output to the three-way downbridge circuit is zero.

4. The servo motor dynamic braking method according to claim 1, characterized in that, The control circuit for the three lower bridges executes multiple stages of pulse width modulation (PWM) signal chopping in ascending order of duty cycle, including: The three lower bridge circuits are controlled to perform chopping action of the pulse width modulation (PWM) signal with a preset first duty cycle in the first stage for a preset first time period; The three lower bridge circuits are controlled to perform chopping action of the pulse width modulation (PWM) signal in the second stage with a preset second duty cycle for a preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the third stage with a preset third duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fourth stage with a preset fourth duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fifth stage with a preset fifth duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the sixth stage with a preset sixth duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the seventh stage with a preset seventh duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform chopping action of the pulse width modulation (PWM) signal in the eighth stage with a preset eighth duty cycle for a preset third time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the ninth stage with a preset ninth duty cycle for the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the tenth stage with a preset tenth duty cycle during the preset third time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the eleventh stage with a preset eleventh duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the twelfth stage with a preset twelfth duty cycle during the preset third time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the thirteenth stage with a preset thirteenth duty cycle during the preset second time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fourteenth stage with a preset fourteenth duty cycle during the preset third time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the fifteenth stage with a preset fifteenth duty cycle for the preset first time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the sixteenth stage with a preset sixteenth duty cycle during the preset third time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the seventeenth stage with a preset seventeenth duty cycle for the preset first time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the eighteenth stage with a preset eighteenth duty cycle during the preset third time period; The three lower bridge circuits are controlled to perform the chopping action of the pulse width modulation (PWM) signal in the nineteenth stage with a preset nineteenth duty cycle for the preset first time period; The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the twentieth stage with a preset twentieth duty cycle for the preset first time period; The three lower bridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 21st stage with a preset 21st duty cycle for the preset first time period; The three downbridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 22nd stage with a preset 22nd duty cycle for the preset first time period; The three lower bridge circuits are controlled to perform chopping of the pulse width modulation (PWM) signal in the 23rd stage with a preset 23rd duty cycle for a preset fourth time period.

5. The servo motor dynamic braking method according to any one of claims 2 to 4, characterized in that, The step of determining whether the residual electrical energy has been completely released based on the current during the preset chopping time period includes: The current during the preset chopping time period is compared with a preset current threshold range; When the current during the preset chopping time period is within the current threshold range, it is determined that the residual electrical energy has been completely released. If the current during the preset chopping time period is not entirely within the current threshold range, it is determined that the residual electrical energy has not been fully released.

6. The servo motor dynamic braking method according to claim 5, characterized in that, The method further includes: When it is determined that the remaining electrical energy has not been completely released, the three lower bridge circuits continue to be controlled to perform the chopping action of the PWM signal in the last stage until the remaining electrical energy is completely released.

7. The servo motor dynamic braking method according to claim 6, characterized in that, The chopping action of the final stage PWM signal in controlling the three lower bridge circuits also includes: Output activation signal to current detection module; The current detection module is controlled to detect the current of the control circuit of the servo motor.

8. A servo motor dynamic braking system, characterized in that, The system includes an intelligent power module, a speed detection module, and a current detection module. The intelligent power module is used to implement the steps of the servo motor dynamic braking method as described in any one of claims 1 to 7.

9. A smart power module, characterized in that, The system includes a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the servo motor dynamic braking method as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the servo motor dynamic braking method as described in any one of claims 1 to 7.

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