Method and device for detecting disconnection, equipment and storage medium

Abstract

The embodiment of the invention provides a disconnection detection method and device, equipment and a storage medium. By adopting the method, firstly, corresponding voltage can be input to the servo motor based on a set direct-axis voltage value and a set quadrature-axis voltage value; then, the detection current value of each phase and the theoretical current value of each phase of the servo motor are obtained; and finally, judging whether the power line of the servo motor is broken or not by determining whether the detection current value of each phase and the theoretical current value of each phase meet difference conditions or not. And when the judgment result is disconnection, carrying out disconnection safety early warning processing. In this way, the safety problem caused by power line breakage can be avoided. Besides, under the condition that the direct-axis voltage value is not 0 and the quadrature-axis voltage value is 0, the servo motor is powered on but does not work (that is, the rotor does not rotate), and the safety of the detection process can be ensured.

Description

Technical Field

[0001] The present disclosure relates to the field of mechanical technology, and in particular to a method, device, equipment and storage medium for detecting disconnection. Background Art

[0002] In the field of mechanical technology, servo drive equipment is a device that provides power for mechanical equipment. Servo drive equipment is generally composed of a power inverter and a servo motor. The power inverter and the servo motor are connected through a power line. The power inverter provides power to the servo motor. The servo motor can output linear or rotational motion to drive the mechanical equipment to move.

[0003] During the long-term operation of the servo motor, the power line may be broken due to wear, aging, etc. When the power line is broken, it will cause the servo motor to stop or the speed to lose control, further affecting the normal operation of the mechanical equipment. Therefore, a method for detecting whether the power line is broken is needed. Summary of the invention

[0004] The present disclosure provides a method, device, equipment and storage medium for detecting disconnection, which can solve related technical problems. The technical solution is as follows:

[0005] In a first aspect, a method for detecting disconnection is provided, the method comprising:

[0006] Based on a target direct-axis voltage value and a target quadrature-axis voltage value, the servo motor is controlled, and a theoretical current value of each phase of the servo motor is determined, wherein the target direct-axis voltage value is not equal to 0, and the target quadrature-axis voltage value is equal to 0;

[0007] Obtaining the detection current value of each phase of the servo motor;

[0008] When the detected current value of each phase and the theoretical current value of each phase meet the specified difference condition, a line break safety warning process is performed.

[0009] In a possible implementation, the controlling the servo motor based on the target direct-axis voltage value and the target quadrature-axis voltage value and determining the theoretical current value of each phase of the servo motor includes:

[0010] Determining the voltage duty cycle of each phase based on the target direct-axis voltage value and the target quadrature-axis voltage value;

[0011] Based on the duty cycle of each phase voltage, controlling the power inverter to output each phase AC voltage to the servo motor;

[0012] Based on the duty cycle of the voltage of each phase, a theoretical current value of each phase of the servo motor is determined.

[0013] In a possible implementation, determining the duty cycle of each phase voltage based on the target direct-axis voltage value and the target quadrature-axis voltage value includes:

[0014] Obtaining the rotor electrical angle of the servo motor and the DC bus voltage value of the power inverter;

[0015] The voltage duty ratio of each phase is determined based on the target direct-axis voltage value, the target quadrature-axis voltage value, the rotor electrical angle, and the DC bus voltage value.

[0016] In a possible implementation, determining the theoretical current value of each phase of the servo motor based on the duty cycle of each phase voltage includes:

[0017] Obtaining the resistance value of each phase of the servo motor and the DC bus voltage value of the power inverter;

[0018] Based on the duty cycle of the voltage of each phase, the DC bus voltage value and the resistance value of each phase, a theoretical current value of each phase is determined.

[0019] In a possible implementation, determining the theoretical current value of each phase based on the voltage duty cycle of each phase, the DC bus voltage value, and the resistance value of each phase includes:

[0020] Based on the formula Determine the theoretical current value of each phase;

[0021] Where n = 1, 2, ... N, N is the number of phases of the servo motor, I n is the theoretical current value of each phase, U dc is the DC bus voltage value, D no is the duty cycle of each phase voltage, D0 is the average value of each phase voltage duty cycle, and R is the resistance value of each phase.

[0022] In a possible implementation, the servo motor is a three-phase servo motor, and obtaining the detection current value of each phase of the servo motor includes:

[0023] Obtaining detection current values ​​of any two phases of the servo motor;

[0024] Based on the detected current values ​​of any two phases, the detected current value of another phase among the three phases of the servo motor is determined.

[0025] In a possible implementation, the difference condition is: among the detected current values ​​of each phase and the theoretical current values ​​of each phase, the absolute value of the difference between the detected current value of any phase and the corresponding theoretical current value is greater than an error threshold.

[0026] In a possible implementation, the performing disconnection safety warning processing includes:

[0027] Display disconnection prompt message; and / or,

[0028] The servo motor is kept in a rotor position locked state.

[0029] In a second aspect, a device for detecting disconnection is provided, the device comprising:

[0030] A determination module, used to control the servo motor based on a target direct-axis voltage value and a target quadrature-axis voltage value, and determine a theoretical current value of each phase of the servo motor, wherein the target direct-axis voltage value is not equal to 0, and the target quadrature-axis voltage value is equal to 0;

[0031] An acquisition module, used for acquiring the detection current value of each phase of the servo motor;

[0032] The processing module is used to perform disconnection safety warning processing when the detected current value of each phase and the theoretical current value of each phase meet the specified difference condition.

[0033] In a possible implementation manner, the determining module is used to:

[0034] Determining the voltage duty cycle of each phase based on the target direct-axis voltage value and the target quadrature-axis voltage value;

[0035] Based on the duty cycle of each phase voltage, controlling the power inverter to output each phase AC voltage to the servo motor;

[0036] Based on the duty cycle of the voltage of each phase, a theoretical current value of each phase of the servo motor is determined.

[0037] In a possible implementation manner, the determining module is used to:

[0038] Obtaining the rotor electrical angle of the servo motor and the DC bus voltage value of the power inverter;

[0039] The voltage duty ratio of each phase is determined based on the target direct-axis voltage value, the target quadrature-axis voltage value, the rotor electrical angle, and the DC bus voltage value.

[0040] In a possible implementation manner, the determining module is used to:

[0041] Obtaining the resistance value of each phase of the servo motor and the DC bus voltage value of the power inverter;

[0042] Based on the duty cycle of the voltage of each phase, the DC bus voltage value and the resistance value of each phase, a theoretical current value of each phase is determined.

[0043] In a possible implementation manner, the determining module is used to:

[0044] Based on the formula Determine the theoretical current value of each phase;

[0045] Where n = 1, 2, ... N, N is the number of phases of the servo motor, I n is the theoretical current value of each phase, U dc is the DC bus voltage value, D no is the duty cycle of each phase voltage, D0 is the average value of each phase voltage duty cycle, and R is the resistance value of each phase.

[0046] In a possible implementation, the servo motor is a three-phase servo motor, and the acquisition module is used to:

[0047] Obtaining detection current values ​​of any two phases of the servo motor;

[0048] Based on the detected current values ​​of any two phases, the detected current value of another phase among the three phases of the servo motor is determined.

[0049] In a possible implementation, the difference condition is: among the detected current values ​​of each phase and the theoretical current values ​​of each phase, the absolute value of the difference between the detected current value of any phase and the corresponding theoretical current value is greater than an error threshold.

[0050] In a possible implementation, the processing module is used to:

[0051] Display disconnection prompt message; and / or,

[0052] The servo motor is kept in a rotor position locked state.

[0053] In a third aspect, a computer device is provided, comprising a memory and a processor, wherein the memory is used to store computer instructions; the processor executes the computer instructions stored in the memory so that the computer device executes the method of the first aspect and possible implementations thereof.

[0054] In a fourth aspect, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program code. When the computer program code is executed by a computer device, the computer device executes the method of the first aspect and possible implementations thereof.

[0055] In a fifth aspect, a computer program product is provided. The computer program product includes a computer program code. When the computer program code is executed by a computer device, the computer device executes the method of the first aspect and possible implementations thereof.

[0056] The technical solution provided by the embodiments of the present disclosure may have the following beneficial effects:

[0057] Through the method provided by the embodiment of the present disclosure, first, the corresponding voltage can be input to the servo motor based on the set direct-axis voltage value and the quadrature-axis voltage value. Then, the detected current value of each phase and the theoretical current value of each phase of the servo motor are obtained. Finally, by determining whether the detected current value of each phase and the theoretical current value of each phase meet the difference condition, it is judged whether the power line of the servo motor is broken. In the case where the judgment result is a broken line, a broken line safety warning process is performed. In this way, safety issues caused by broken power lines can be avoided. In addition, when the direct-axis voltage value is not 0 and the quadrature-axis voltage value is 0, the servo motor is powered on but does not work (that is, the rotor does not rotate), which can ensure the safety of the detection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0059] Figure 1 is a structural schematic diagram of a servo drive system provided by an embodiment of the present disclosure;

[0060] Figure 2 It is a structural schematic diagram of a single chip computer provided by an embodiment of the present disclosure;

[0061] Figure 3 is a flow chart of a method for detecting disconnection provided by an embodiment of the present disclosure;

[0062] Figure 4 is a schematic diagram of outputting a three-phase AC voltage provided by an embodiment of the present disclosure;

[0063] Figure 5 is a schematic diagram of the structure of a device for detecting disconnection provided by an embodiment of the present disclosure;

[0064] Figure 6 It is a structural diagram of a terminal provided by an embodiment of the present disclosure. DETAILED DESCRIPTION

[0065] The present disclosure provides a method for detecting a broken wire, which is applied to a servo drive system. The servo drive system can be used to output rotation or linear motion to a mechanical device or mechanical component. The servo drive system can include a power inverter, a servo motor, and a single-chip microcomputer. The structure can be as follows: Figure 1As shown. The servo drive system may not include a single-chip microcomputer, that is, the servo drive system may be controlled by an external terminal. Among them, the power inverter is mainly used to provide power for the servo motor and convert direct current into alternating current. The servo motor may include a rotor and a stator, etc. The rotor may be a permanent magnet. When the winding coil of the stator is energized to generate a magnetic field, and the direction of the magnetic field is inconsistent with the direction of the rotor magnetic field, the rotor will rotate. This method can be executed by an external terminal, etc., or by a single-chip microcomputer in the servo drive system.

[0066] The embodiments of the present disclosure are described by taking a single chip microcomputer as an example of an execution subject.

[0067] From the perspective of hardware composition, the structure of the microcontroller can be as follows Figure 2 As shown, it includes a processor 201 and a memory 202 .

[0068] The processor 210 may be a CPU, etc., and the processor 310 may be used to execute various instructions involved in the method, etc.

[0069] The memory 220 may include various volatile memories or non-volatile memories, such as RAM (random access memory), ROM (read-only memory), etc. The memory 220 may be used to store pre-stored data, intermediate data, and result data in detecting disconnection, such as voltage values, etc.

[0070] In addition to the processor and memory, the microcontroller may also include a counter / timer circuit (CTC) that clears when a compare match is found.

[0071] Below, several terms involved in this embodiment are introduced:

[0072] Three-phase: It is the most common type of multi-phase AC system.

[0073] Three-phase alternating current: It is a form of electric energy transmission, referred to as three-phase electricity. Three-phase alternating current is a power source composed of three alternating potentials with the same frequency, equal amplitude and 120° phase difference.

[0074] Three-phase AC circuit: A circuit powered by three-phase AC power is referred to as a three-phase circuit. A three-phase circuit includes a three-phase power supply and a three-phase load.

[0075] Servo three-phase motor: It is an induction motor that works by inputting three-phase alternating current. The stator winding in the servo three-phase motor can be considered as a three-phase load in a three-phase circuit.

[0076] Encoder: The full name is servo motor encoder. The encoder is a component of the servo motor and is a sensor used to measure the magnetic pole position, rotation angle and speed of the servo motor.

[0077] Two-phase rotating coordinate system: It is a two-dimensional plane coordinate system, generally called the dq coordinate system. This coordinate system is a relatively stationary coordinate system with the rotor, and a relatively rotating coordinate system with the stator. The d-axis of this coordinate system is parallel to the line connecting the magnetic poles (N pole and S pole) of the rotor, and the q-axis is perpendicular to the line and points to the stator. By adjusting the voltage of the d-axis, the amplitude of the voltage of each phase of the three-phase alternating current is actually adjusted, and further, the speed of the servo motor can be adjusted. By adjusting the voltage of the q-axis, the phase of the voltage of each phase of the three-phase alternating current is actually adjusted, and the torque of the servo motor can be further adjusted. When the torque is 0, the rotor in the servo motor does not rotate. When the torque is not 0, the rotor in the servo motor rotates.

[0078] Two-phase stationary coordinate system: It is a two-dimensional plane coordinate system, generally called αβ coordinate system. This coordinate system is a relatively rotating coordinate system with the rotor, and is a relatively stationary coordinate system with the stator.

[0079] Three-phase stationary coordinate system: It is a three-dimensional plane coordinate system, generally called the abc coordinate system. This coordinate system is a coordinate system that rotates relative to the rotor and is a coordinate system that is relatively stationary relative to the stator.

[0080] In the field of mechanical technology, servo drive systems can be used to control the movement of various types of mechanical equipment. Generally, technicians can set the control instructions in advance. After pressing the switch of the servo drive system, the servo drive system can control the mechanical equipment to move accordingly according to the control instructions to complete the task. However, the power line of the servo motor in the servo drive system may be worn out due to long working hours, and then the line may be broken. The power line breakage may cause the rotor in the servo motor to be out of control, which may cause the servo drive system to work more dangerously or fail to work. Therefore, before turning on the servo drive system each time, the power line of the servo motor can be detected for line breakage.

[0081] The present disclosure provides a method for detecting disconnection in view of the above application scenarios. Figure 3 As shown, the processing flow of the method may include the following steps:

[0082] 301 , based on the target direct-axis voltage value and the target quadrature-axis voltage value, control the servo motor and determine the theoretical current value of each phase of the servo motor.

[0083] Among them, the target direct-axis voltage value is not equal to 0, and the target quadrature-axis voltage value is equal to 0. In FOC (field oriented control) theory, the direct-axis voltage value and the quadrature-axis voltage value are the voltage values ​​of the stator in the dq coordinate system, which can be equivalent to the three-phase voltage. The technician can intuitively adjust the magnetic field generated by the stator by adjusting the direct-axis voltage value and the quadrature-axis voltage value so that the three-phase voltage output by the power inverter can make the target magnetic field generated by the stator meet the requirements. The direct-axis voltage value represents the voltage value corresponding to the component of the target magnetic field in the d-axis direction, and the quadrature-axis voltage value represents the voltage value corresponding to the component of the target magnetic field in the q-axis direction. The servo motor is a servo three-phase motor. The theoretical current value of each phase is the theoretical current value on the power line corresponding to each phase of the servo motor (such as the u-phase, v-phase and w-phase in the three-phase motor) obtained by calculation.

[0084] In practice, when the technician clicks the control to start working or presses the working button of the servo drive system on the terminal, the microcontroller in the servo drive system obtains the instruction to start working. At this time, the microcontroller will first detect whether the power line of the servo drive system is broken.

[0085] Optionally, the single chip microcomputer can determine the voltage duty cycle of each phase by obtaining the target direct-axis voltage value and the target quadrature-axis voltage value, so as to control the power inverter to output the AC voltage of each phase and calculate the theoretical current value of each phase. Accordingly, the specific processing steps of step 301 may include:

[0086] Step 1: Obtain the rotor electrical angle of the servo motor and the DC bus voltage value of the power inverter. Determine the voltage duty cycle of each phase based on the target direct-axis voltage value, the target quadrature-axis voltage value, the rotor electrical angle and the DC bus voltage value.

[0087] In practice, the servo motor is equipped with a sensor for monitoring the rotor position. For example, the sensor can be a servo motor encoder. The encoder can detect the real-time mechanical angle of the rotor. In this way, when the single-chip microcomputer starts to detect the broken wire, the mechanical angle of the rotor can be obtained through the encoder first. Further, the corresponding relationship between the mechanical angle and the rotor electrical angle is used to determine the corresponding rotor electrical angle. In addition, the single-chip microcomputer also needs to obtain the DC bus voltage value of the driver.

[0088] Then, the single chip microcomputer can input the rotor electrical angle, the target direct axis voltage value and the target quadrature axis voltage value into the ipark transformation model to obtain the two voltage values ​​of the stator in the αβ coordinate system, namely, U α and U β Among them, the ipark transformation model is a coordinate transformation model, which is used to transform the rotating dq coordinate system into the stationary αβ coordinate system. The microcontroller converts the calculated U α , U βThe obtained DC bus voltage is input into the SVPWM (space vector pulse width modulation) model to obtain the three-phase voltage duty cycle of the stator, that is, D ao , D bo and D co .

[0089] The voltage duty cycle of each phase can also be obtained through the following calculation process:

[0090] U α = cosθ e U d -sinθ e U q (1)

[0091] U β = sinθ e U d +cosθ e U q (2)

[0092] Among them, U α is the voltage value of the stator on the α axis in the αβ coordinate system, U β is the voltage value of the stator on the β axis in the αβ coordinate system, θ e is the rotor electrical angle, U d is the target direct-axis voltage value, U q is the target quadrature-axis voltage value.

[0093] Introducing three intermediate variables X, Y and Z, the mathematical expression is as follows:

[0094]

[0095]

[0096]

[0097] Further, determine the maximum value U among X, Y and Z max and the minimum value U min , and calculate the intermediate value U based on the maximum and minimum values n , the corresponding mathematical expression is as follows:

[0098] U max =max[X, Y, Z] (6)

[0099] U min =min[X, Y, Z] (7)

[0100] U n =(U max -Umin )×0.5 (8)

[0101] Then, calculate the duty cycle D of the servo motor phases a, b, and c ao , D bo and D co , the mathematical expression can be as follows:

[0102]

[0103]

[0104]

[0105] Among them, U dc is the DC bus voltage value.

[0106] In FCO theory, when the direct-axis voltage value of the stator is not equal to 0 and the quadrature-axis voltage value is equal to 0, the voltage vector of the stator in the dq coordinate system is on the direct axis (d axis). In this case, the magnetic field generated by the stator coincides with the magnetic field of the rotor, the servo motor has no torque, and the rotor does not rotate. At this time, the servo motor is powered but not working, and it is safer to detect wire breakage in this state.

[0107] In other possible implementations, the duty cycle of each phase voltage may also be calculated using other parameters.

[0108] Step 2: Based on the duty cycle of each phase voltage, control the power inverter to output each phase AC voltage to the servo motor.

[0109] In the implementation, the microcontroller transmits the three-phase voltage duty cycle to the power inverter, and the power inverter adjusts the DC voltage output by the power inverter according to the received three-phase voltage duty cycle, obtains the adjusted three-phase AC voltage and outputs it to the stator. The stator is energized and generates a corresponding magnetic field. The schematic diagram of the above processing process can be shown as follows Figure 4 shown.

[0110] Step 3: Obtain the resistance value of each phase of the servo motor and the DC bus voltage value of the power inverter. Determine the theoretical current value of each phase based on the voltage duty cycle of each phase, the DC bus voltage value and the resistance value of each phase.

[0111] The phase resistance value is the resistance value of each corresponding winding coil in the servo motor.

[0112] In practice, the theoretical current values ​​I of phases a, b, and c are calculated. ar ,I br and I cr , the mathematical expression can be as follows:

[0113]

[0114]

[0115]

[0116] in, R is the resistance value of each phase. In the embodiment of the present disclosure, it is taken as an example that the resistance values ​​of each phase are equal.

[0117] In other possible implementations, the theoretical current value of each phase may also be calculated using other parameters.

[0118] It should be noted that step 2 and step 3 may be performed in any order.

[0119] 302, obtaining the detection current value of each phase of the servo motor.

[0120] Among them, the detected current value of each phase is the actual current value in each phase power line after the servo motor is powered on.

[0121] In implementation, a current sensor may be provided in the servo motor, and the single chip microcomputer may obtain the detection current value of each phase of the servo motor through the current sensor.

[0122] Optionally, the single chip microcomputer may obtain the detection current values ​​of any two phases of the three phases of the servo motor. Accordingly, the specific processing method of step 302 may be:

[0123] The detection current values ​​of any two phases of the servo motor are obtained. Based on the detection current values ​​of any two phases, the detection current value of another phase among the three phases of the servo motor is determined.

[0124] In practice, in a three-phase circuit, the sum of the three-phase currents is 0, that is, I a +I b +I c =0. Therefore, the single-chip microcomputer can only obtain the detection current values ​​of any two phases of the servo motor, and then obtain the detection current value of the third phase by calculation. For example, the single-chip microcomputer obtains the detection current value I of phase a and phase b af and I bf After that, the detection current value of phase c can be obtained as I cf =-(I af +I bf ).

[0125] In other possible implementations, the single chip microcomputer may also directly obtain the detection current values ​​of the three phases of the servo motor.

[0126] 303, when the detected current value of each phase and the theoretical current value of each phase meet the specified difference condition, a line break safety warning process is performed.

[0127] The difference condition may be that the absolute value of the difference between the detected current value of each phase and the corresponding theoretical current value of each phase is greater than the error threshold. The difference condition may also be that the average of the absolute values ​​of the difference between the detected current value of each phase and the theoretical current value of each phase is greater than the error threshold.

[0128] In implementation, after the single-chip microcomputer obtains the three-phase detection current value and calculates the three-phase theoretical current value, the absolute value of the difference between the detection current value and the theoretical current value of any phase can be calculated first, and the absolute value of the difference can be compared with the error threshold. If the absolute value of the difference is greater than the error threshold, a safety warning process can be performed without calculating the absolute value of the difference of other phases. If the absolute value of the difference is less than the error threshold, the absolute value of the difference between the detection current value and the theoretical current value of the second phase is calculated, and the absolute value of the difference is continued to be compared with the error threshold, and so on. If the absolute value of the difference of the second phase is still less than the error threshold, the absolute value of the difference between the detection current value and the theoretical current value of the third phase is calculated, and the absolute value of the difference is continued to be compared with the error threshold. If the absolute value of the difference of the third phase is greater than the error threshold, a safety warning process can be performed. If the absolute value of the difference of the third phase is less than the error threshold, the single-chip microcomputer can adjust the direct-axis voltage value and the quadrature-axis voltage value through the obtained control instruction to control the servo motor to work.

[0129] Alternatively, after the single-chip microcomputer obtains the three-phase detection current value and the three-phase theoretical current value, the mean of the absolute value of the difference between the three-phase detection current value and the theoretical current value can be calculated. When the mean is greater than the error threshold, a safety warning is performed. Otherwise, the single-chip microcomputer can adjust the direct-axis voltage value and the quadrature-axis voltage value through the obtained control instructions to control the servo motor to work.

[0130] When the three-phase detection current value and the three-phase theoretical current value meet the specified difference conditions, it means that the power line of the servo power is broken and there is a safety problem with the related equipment. At this time, the disconnection safety warning processing can be carried out;

[0131] First, display the disconnection prompt information.

[0132] In practice, the single-chip microcomputer can control the corresponding indicator light of the device to flash or display a red light, etc., to remind the technician that the power line of the servo motor is broken and needs to be repaired. If the device has a display screen, the disconnection prompt information can also be displayed on the display screen, for example, "The power line of the servo motor is broken, please check."

[0133] In other possible implementations, the power line between the servo motor and the power inverter may have a corresponding identification. When the detected current value and the theoretical current value of any phase meet the difference condition, the identification of the phase can be determined. Furthermore, the relevant equipment can be controlled to display the corresponding indicator light to prompt the technician to check and repair the corresponding power line. Alternatively, when the display screen displays the disconnection prompt information, the disconnection prompt information may include the phase identification, for example, "The power line of phase a of the servo motor is disconnected, please check."

[0134] Second, keep the servo motor in the rotor position locked state.

[0135] In implementation, for safety reasons, the MCU can continue to control the inverter to inject the target quadrature-axis voltage value of 0 and the target direct-axis voltage corresponding to non-0 into the servo motor without any processing, so as to continue to keep the rotor position unchanged. Alternatively, the MCU can control the power inverter to stop injecting voltage into the servo motor so that the stator is not energized and a magnetic field cannot be generated. As a result, the servo motor cannot generate torque, the rotor will not rotate, and its position can be kept in a locked state.

[0136] Through the method provided by the embodiment of the present disclosure, first, the corresponding voltage can be input to the servo motor based on the set direct-axis voltage value and the quadrature-axis voltage value. Then, the detected current value of each phase and the theoretical current value of each phase of the servo motor are obtained. Finally, by determining whether the detected current value of each phase and the theoretical current value of each phase meet the difference condition, it is judged whether the power line of the servo motor is broken. In the case where the judgment result is a broken line, a broken line safety warning process is performed. In this way, safety issues caused by broken power lines can be avoided. In addition, when the direct-axis voltage value is not 0 and the quadrature-axis voltage value is 0, the servo motor is powered on but does not work (that is, the rotor does not rotate), which can ensure the safety of the detection process.

[0137] All the above optional technical solutions can be arbitrarily combined to form optional embodiments of the present disclosure, and will not be described in detail here.

[0138] Based on the same technical concept, the embodiment of the present disclosure also provides a device for detecting disconnection, which can be applied to the single chip microcomputer or terminal in the above embodiment, such as Figure 5 As shown, the device comprises:

[0139] A determination module 510 is used to control the servo motor based on a target direct-axis voltage value and a target quadrature-axis voltage value, and determine a theoretical current value of each phase of the servo motor, wherein the target direct-axis voltage value is not equal to 0, and the target quadrature-axis voltage value is equal to 0;

[0140] An acquisition module 520 is used to acquire the detection current value of each phase of the servo motor;

[0141] The processing module 530 is used to perform disconnection safety warning processing when the detected current value of each phase and the theoretical current value of each phase meet the specified difference condition.

[0142] In a possible implementation, the determination module 510 is configured to:

[0143] Determining the voltage duty cycle of each phase based on the target direct-axis voltage value and the target quadrature-axis voltage value;

[0144] Based on the duty cycle of each phase voltage, the power inverter is controlled to output each phase AC voltage to the servo motor;

[0145] Based on the duty cycle of each phase voltage, the theoretical current value of each phase of the servo motor is determined.

[0146] In a possible implementation, the determination module 510 is configured to:

[0147] Obtain the rotor electrical angle of the servo motor and the DC bus voltage value of the power inverter;

[0148] The duty cycle of each phase voltage is determined based on the target direct-axis voltage value, the target quadrature-axis voltage value, the rotor electrical angle and the DC bus voltage value.

[0149] In a possible implementation, the determination module 510 is configured to:

[0150] Obtain the resistance value of each phase of the servo motor and the DC bus voltage value of the power inverter;

[0151] The theoretical current value of each phase is determined based on the voltage duty cycle of each phase, the DC bus voltage value and the resistance value of each phase.

[0152] In a possible implementation, the determination module 510 is configured to:

[0153] Based on the formula Determine the theoretical current value of each phase;

[0154] Where n = 1, 2, ... N, N is the number of phases of the servo motor, I n is the theoretical current value of each phase, U dc is the DC bus voltage value, D no is the duty cycle of each phase voltage, D0 is the average value of each phase voltage duty cycle, and R is the resistance value of each phase.

[0155] In a possible implementation, the servo motor is a servo three-phase motor, and the acquisition module 520 is used to:

[0156] Get the detection current values ​​of any two phases of the servo motor;

[0157] Based on the detected current values ​​of any two phases, the detected current value of another phase among the three phases of the servo motor is determined.

[0158] In a possible implementation, the difference condition is: among the detected current values ​​of each phase and the theoretical current values ​​of each phase, the absolute value of the difference between the detected current value of any phase and the corresponding theoretical current value is greater than an error threshold.

[0159] In a possible implementation, the processing module 530 is configured to:

[0160] Display disconnection prompt message; and / or,

[0161] Keep the servo motor in the rotor position locked state.

[0162] Through the device provided by the embodiment of the present disclosure, first, the corresponding voltage can be input to the servo motor based on the set direct-axis voltage value and the cross-axis voltage value. Then, the detected current value of each phase and the theoretical current value of each phase of the servo motor are obtained. Finally, by determining whether the detected current value of each phase and the theoretical current value of each phase meet the difference condition, it is judged whether the power line of the servo motor is broken. In the case where the judgment result is a broken line, a broken line safety warning is processed. In this way, safety issues caused by broken power lines can be avoided. In addition, when the direct-axis voltage value is not 0 and the cross-axis voltage value is 0, the servo motor is powered on but does not work (that is, the rotor does not rotate), which can ensure the safety of the detection process.

[0163] It should be noted that: the device for detecting disconnection provided in the above embodiment only uses the division of the above functional modules as an example when detecting disconnection. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the single-chip microcomputer or the terminal is divided into different functional modules to complete all or part of the functions described above. In addition, the device for detecting disconnection provided in the above embodiment and the method embodiment for detecting disconnection belong to the same concept. The specific implementation process is detailed in the method embodiment and will not be repeated here.

[0164] Figure 6 The structure block diagram of the terminal 600 provided by the embodiment of the present disclosure is shown. The terminal 600 may be a portable mobile terminal, such as a smart phone, a tablet computer, an MP3 player (moving picture experts group audio layer III, dynamic image expert compression standard audio layer 3), an MP4 (moving picture experts group audio layer IV, dynamic image expert compression standard audio layer 4) player, a notebook computer or a desktop computer. The terminal 600 may also be called a user device, a portable terminal, a laptop terminal, a desktop terminal or other names.

[0165] Typically, the terminal 600 includes a processor 601 and a memory 602 .

[0166] The processor 601 may include one or more processing cores, such as a 4-core processor, an 8-core processor, etc. The processor 601 may be implemented in at least one hardware form of DSP (digital signal processing), FPGA (field-programmable gate array), and PLA (programmable logic array). The processor 601 may also include a main processor and a coprocessor. The main processor is a processor for processing data in the awake state, also known as a CPU (central processing unit); the coprocessor is a low-power processor for processing data in the standby state. In some embodiments, the processor 601 may be integrated with a GPU (graphics processing unit), which is responsible for rendering and drawing the content to be displayed on the display screen. In some embodiments, the processor 601 may also include an AI (artificial intelligence) processor, which is used to process computing operations related to machine learning.

[0167] The memory 602 may include one or more computer-readable storage media, which may be non-transitory. The memory 602 may also include a high-speed random access memory, and a non-volatile memory, such as one or more disk storage devices, flash memory storage devices. In some embodiments, the non-transitory computer-readable storage medium in the memory 602 is used to store at least one instruction, which is used to be executed by the processor 601 to implement the method provided in the embodiment of the present disclosure.

[0168] In some embodiments, the terminal 600 may further optionally include: a peripheral device interface 603 and at least one peripheral device. The processor 601, the memory 602 and the peripheral device interface 603 may be connected via a bus or a signal line. Each peripheral device may be connected to the peripheral device interface 603 via a bus, a signal line or a circuit board. Specifically, the peripheral device includes: at least one of a radio frequency circuit 604, a display screen 605, a camera assembly 606, an audio circuit 607, a positioning assembly 608 and a power supply 609.

[0169] The peripheral device interface 603 may be used to connect at least one peripheral device related to I / O (Input / Output) to the processor 601 and the memory 602. In some embodiments, the processor 601, the memory 602, and the peripheral device interface 603 are integrated on the same chip or circuit board; in some other embodiments, any one or two of the processor 601, the memory 602, and the peripheral device interface 603 may be implemented on a separate chip or circuit board, which is not limited in this embodiment.

[0170] The radio frequency circuit 604 is used to receive and transmit RF (radio frequency) signals, also known as electromagnetic signals. The radio frequency circuit 604 communicates with the communication network and other communication devices through electromagnetic signals. The radio frequency circuit 604 converts the electrical signal into an electromagnetic signal for transmission, or converts the received electromagnetic signal into an electrical signal. Optionally, the radio frequency circuit 604 includes: an antenna system, an RF transceiver, one or more amplifiers, a tuner, an oscillator, a digital signal processor, a codec chipset, a user identity module card, etc. The radio frequency circuit 604 can communicate with other terminals through at least one wireless communication protocol. The wireless communication protocol includes but is not limited to: the World Wide Web, a metropolitan area network, an intranet, various generations of mobile communication networks (2G, 3G, 4G and 5G), a wireless local area network and / or a WiFi (wireless fidelity) network. In some embodiments, the radio frequency circuit 604 may also include circuits related to NFC (near field communication), which is not limited in this application.

[0171] The display screen 605 is used to display a UI (user interface). The UI may include graphics, text, icons, videos, and any combination thereof. When the display screen 605 is a touch display screen, the display screen 605 also has the ability to collect touch signals on the surface or above the surface of the display screen 605. The touch signal can be input as a control signal to the processor 601 for processing. At this time, the display screen 605 can also be used to provide virtual buttons and / or virtual keyboards, also known as soft buttons and / or soft keyboards. In some embodiments, the display screen 605 can be one, set on the front panel of the terminal 600; in other embodiments, the display screen 605 can be at least two, respectively set on different surfaces of the terminal 600 or in a folding design; in other embodiments, the display screen 605 can be a flexible display screen, set on a curved surface or a folding surface of the terminal 600. Even, the display screen 605 can also be set to a non-rectangular irregular shape, that is, a special-shaped screen. The display screen 605 can be made of materials such as LCD (liquid crystal display), OLED (organic light-emitting diode), etc.

[0172] The camera assembly 606 is used to capture images or videos. Optionally, the camera assembly 606 includes a front camera and a rear camera. Typically, the front camera is arranged on the front panel of the terminal, and the rear camera is arranged on the back of the terminal. In some embodiments, there are at least two rear cameras, which are any one of a main camera, a depth of field camera, a wide-angle camera, and a telephoto camera, so as to realize the fusion of the main camera and the depth of field camera to realize the background blur function, the fusion of the main camera and the wide-angle camera to realize panoramic shooting and VR (virtual reality) shooting function or other fusion shooting functions. In some embodiments, the camera assembly 606 may also include a flash. The flash can be a monochrome temperature flash or a dual-color temperature flash. A dual-color temperature flash refers to a combination of a warm light flash and a cold light flash, which can be used for light compensation at different color temperatures.

[0173] The audio circuit 607 may include a microphone and a speaker. The microphone is used to collect sound waves from the user and the environment, and convert the sound waves into electrical signals and input them into the processor 601 for processing, or input them into the radio frequency circuit 604 to achieve voice communication. For the purpose of stereo acquisition or noise reduction, there may be multiple microphones, which are respectively arranged at different parts of the terminal 600. The microphone may also be an array microphone or an omnidirectional acquisition microphone. The speaker is used to convert the electrical signal from the processor 601 or the radio frequency circuit 604 into sound waves. The speaker may be a traditional film speaker or a piezoelectric ceramic speaker. When the speaker is a piezoelectric ceramic speaker, it can not only convert the electrical signal into sound waves audible to humans, but also convert the electrical signal into sound waves inaudible to humans for purposes such as ranging. In some embodiments, the audio circuit 607 may also include a headphone jack.

[0174] The positioning component 608 is used to locate the current geographical location of the terminal 600 to implement navigation or LBS (location based service). The positioning component 608 can be a positioning component based on GPS (global positioning system), Beidou system or Galileo system.

[0175] The power supply 609 is used to power various components in the terminal 600. The power supply 609 can be an alternating current, a direct current, a disposable battery, or a rechargeable battery. When the power supply 609 includes a rechargeable battery, the rechargeable battery can be a wired rechargeable battery or a wireless rechargeable battery. A wired rechargeable battery is a battery charged through a wired line, and a wireless rechargeable battery is a battery charged through a wireless coil. The rechargeable battery can also be used to support fast charging technology.

[0176] In some embodiments, the terminal 600 further includes one or more sensors 610 , including but not limited to: an acceleration sensor 611 , a gyroscope sensor 612 , a pressure sensor 613 , a fingerprint sensor 614 , an optical sensor 615 , and a proximity sensor 616 .

[0177] The acceleration sensor 611 can detect the magnitude of acceleration on the three coordinate axes of the coordinate system established by the terminal 600. For example, the acceleration sensor 611 can be used to detect the components of gravity acceleration on the three coordinate axes. The processor 601 can control the display screen 605 to display the user interface in a horizontal view or a vertical view according to the gravity acceleration signal collected by the acceleration sensor 611. The acceleration sensor 611 can also be used for collecting game or user motion data.

[0178] The gyro sensor 612 can detect the body direction and rotation angle of the terminal 600, and the gyro sensor 612 can cooperate with the acceleration sensor 611 to collect the user's 3D actions on the terminal 600. The processor 601 can implement the following functions based on the data collected by the gyro sensor 612: motion sensing (such as changing the UI according to the user's tilt operation), image stabilization during shooting, game control, and inertial navigation.

[0179] The pressure sensor 613 can be set on the side frame of the terminal 600 and / or the lower layer of the display screen 605. When the pressure sensor 613 is set on the side frame of the terminal 600, it can detect the user's holding signal of the terminal 600, and the processor 601 performs left and right hand recognition or shortcut operation according to the holding signal collected by the pressure sensor 613. When the pressure sensor 613 is set on the lower layer of the display screen 605, the processor 601 controls the operability controls on the UI interface according to the user's pressure operation on the display screen 605. The operability controls include at least one of a button control, a scroll bar control, an icon control, and a menu control.

[0180] The fingerprint sensor 614 is used to collect the user's fingerprint, and the processor 601 identifies the user's identity based on the fingerprint collected by the fingerprint sensor 614, or the fingerprint sensor 614 identifies the user's identity based on the collected fingerprint. When the user's identity is identified as a trusted identity, the processor 601 authorizes the user to perform relevant sensitive operations, including unlocking the screen, viewing encrypted information, downloading software, paying, and changing settings. The fingerprint sensor 614 can be set on the front, back, or side of the terminal 600. When a physical button or a manufacturer logo is set on the terminal 600, the fingerprint sensor 614 can be integrated with the physical button or the manufacturer logo.

[0181] The optical sensor 615 is used to collect the ambient light intensity. In one embodiment, the processor 601 can control the display brightness of the display screen 605 according to the ambient light intensity collected by the optical sensor 615. Specifically, when the ambient light intensity is high, the display brightness of the display screen 605 is increased; when the ambient light intensity is low, the display brightness of the display screen 605 is reduced. In another embodiment, the processor 601 can also dynamically adjust the shooting parameters of the camera assembly 606 according to the ambient light intensity collected by the optical sensor 615.

[0182] The proximity sensor 616, also called a distance sensor, is usually arranged on the front panel of the terminal 600. The proximity sensor 616 is used to collect the distance between the user and the front of the terminal 600. In one embodiment, when the proximity sensor 616 detects that the distance between the user and the front of the terminal 600 is gradually decreasing, the processor 601 controls the display screen 605 to switch from the screen-on state to the screen-off state; when the proximity sensor 616 detects that the distance between the user and the front of the terminal 600 is gradually increasing, the processor 601 controls the display screen 605 to switch from the screen-off state to the screen-on state.

[0183] Those skilled in the art will understand that Figure 6 The structure shown in the figure does not constitute a limitation on the terminal 600, and the terminal 600 may include more or less components than those shown in the figure, or combine some components, or adopt a different component arrangement.

[0184] In an embodiment of the present disclosure, a computer-readable storage medium is also provided, such as a memory including instructions, and the instructions can be executed by a processor in a terminal to complete the method of performing interactive operations in the above embodiment. The computer-readable storage medium can be non-transitory. For example, the computer-readable storage medium can be a ROM (read-only memory), a RAM (random access memory), a CD-ROM, a magnetic tape, a floppy disk, an optical data storage device, etc.

[0185] It should be noted that the information (including but not limited to user device information, user personal information, etc.), data (including but not limited to data used for analysis, stored data, displayed data, etc.) and signals (including but not limited to signals transmitted between user terminals and other devices, etc.) involved in this disclosure are all authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data need to comply with relevant laws, regulations and standards of relevant countries and regions.

[0186] A person skilled in the art will understand that all or part of the steps to implement the above embodiments may be accomplished by hardware or by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a disk or an optical disk, etc.

[0187] The above descriptions are only some possible embodiments of the present disclosure and are not intended to limit the present disclosure. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. A method for detecting disconnection, characterized in that: The method comprises: Based on a target direct-axis voltage value and a target quadrature-axis voltage value, the servo motor is controlled, and a theoretical current value of each phase of the servo motor is determined, wherein the target direct-axis voltage value is not equal to 0, and the target quadrature-axis voltage value is equal to 0; Obtaining the detection current value of each phase of the servo motor; When the detected current value of each phase and the theoretical current value of each phase meet the specified difference condition, a line break safety warning process is performed.

2. The method according to claim 1, characterized in that The method of controlling the servo motor based on the target direct-axis voltage value and the target quadrature-axis voltage value and determining the theoretical current value of each phase of the servo motor includes: Determining the voltage duty cycle of each phase based on the target direct-axis voltage value and the target quadrature-axis voltage value; Based on the duty cycle of each phase voltage, controlling the power inverter to output each phase AC voltage to the servo motor; Based on the duty cycle of the voltage of each phase, a theoretical current value of each phase of the servo motor is determined.

3. The method according to claim 2, characterized in that The step of determining the duty cycle of each phase voltage based on the target direct-axis voltage value and the target quadrature-axis voltage value includes: Obtaining the rotor electrical angle of the servo motor and the DC bus voltage value of the power inverter; The voltage duty ratio of each phase is determined based on the target direct-axis voltage value, the target quadrature-axis voltage value, the rotor electrical angle, and the DC bus voltage value.

4. The method according to claim 2, characterized in that: Determining the theoretical current value of each phase of the servo motor based on the duty cycle of each phase voltage includes: Obtaining the resistance value of each phase of the servo motor and the DC bus voltage value of the power inverter; Based on the duty cycle of the voltage of each phase, the DC bus voltage value and the resistance value of each phase, a theoretical current value of each phase is determined.

5. The method according to claim 4, characterized in that The determining of the theoretical current value of each phase based on the voltage duty cycle of each phase, the DC bus voltage value and the resistance value of each phase includes: Based on the formula Determine the theoretical current value of each phase; Where n = 1, 2, ... N, N is the number of phases of the servo motor, I n is the theoretical current value of each phase, U dc is the DC bus voltage value, D no is the duty cycle of each phase voltage, D0 is the average value of each phase voltage duty cycle, and R is the resistance value of each phase.

6. The method according to claim 1, characterized in that The servo motor is a servo three-phase motor, and obtaining the detection current value of each phase of the servo motor includes: Obtaining detection current values ​​of any two phases of the servo motor; Based on the detected current values ​​of any two phases, the detected current value of another phase among the three phases of the servo motor is determined.

7. The method according to claim 1, characterized in that The difference condition is that, among the detected current values ​​of each phase and the theoretical current values ​​of each phase, the absolute value of the difference between the detected current value of any phase and the corresponding theoretical current value is greater than an error threshold.

8. The method according to claim 1, characterized in that The disconnection safety warning processing includes: Display disconnection prompt message; and / or, The servo motor is kept in a rotor position locked state.

9. A device for detecting disconnection, characterized in that: The device comprises: A control module, configured to control the servo motor based on a target direct-axis voltage value and a target quadrature-axis voltage value, wherein the target direct-axis voltage value is not equal to 0, and the target quadrature-axis voltage value is equal to 0; A determination module, used to determine the theoretical current value of each phase of the servo motor based on the target direct-axis voltage value and the target quadrature-axis voltage value; An acquisition module, used for acquiring the detection current value of each phase of the servo motor; The processing module is used to perform disconnection safety warning processing when the detected current value of each phase and the theoretical current value of each phase meet the specified difference condition.

10. A computer device, characterized in that: The computer device comprises a memory and a processor, wherein the memory is used to store computer instructions; The processor executes the computer instructions stored in the memory to enable the computer device to perform the method according to any one of claims 1 to 8.

11. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program code. When the computer program code is executed by a computer device, the computer device executes the method according to any one of claims 1 to 8.

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