Motor phase loss detection method, device and electronic equipment

Abstract

The present invention provides a motor phase loss detection method, device and electronic equipment. The method obtains the controller bus voltage, controller three-phase voltage and motor three-phase current of the motor to be tested within any period of time, and performs preprocessing to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values ​​and multiple motor three-phase current effective values; the motor to be tested is judged for phase loss according to the multiple controller bus voltage effective values, multiple controller three-phase voltage effective values ​​and multiple motor three-phase current effective values ​​to obtain a phase loss detection result. The present invention processes the acquired electrical signal by absolute value and converts it into an effective value for phase loss judgment, so that the electrical signal of any time period can be used as a judgment basis, without controlling the motor operation cycle, that is: as long as the motor has an electrical signal, it can perform phase loss detection without running or running at a low speed, thereby realizing phase loss detection of low-speed or unstarted motors.

Description

Technical Field

[0001] The present invention relates to the technical field of motor control, and in particular, to a method, device and electronic device for detecting motor phase loss. Background Art

[0002] The motor drive controller and its driven motor, as the core component system of an electric vehicle, are important targets for real-time research on the functional safety of electric vehicles. Among them, the detection of phase loss faults in the three-phase power line is an important link in functional safety research.

[0003] In the prior art, for the detection of phase loss in a permanent magnet synchronous motor (PMSM), during the operation of the motor, the three-phase currents within a certain period of time are mostly collected, and whether there is a phase loss is judged by determining whether the effective values of the three-phase currents within this period are 0. The sampling time period of this method needs to be exactly equal to the operating cycle of the motor at that time, which is very difficult to control, and it is necessary to process the samples for a period of time to obtain the detection result. When the motor is not rotating or the motor speed is very low, it is very difficult to judge whether the motor has a phase loss. Summary of the Invention

[0004] In view of this, it is necessary to provide a method, device and electronic device for detecting motor phase loss to solve the technical problem of difficult phase loss detection for low-speed or unstarted motors.

[0005] To solve the above problems, the present invention provides a method for detecting motor phase loss, including:

[0006] Obtaining the controller bus voltage, controller three-phase voltage and motor three-phase current of the motor to be tested within any period of time;

[0007] Preprocessing the controller bus voltage, the controller three-phase voltage and the motor three-phase current to obtain a plurality of controller bus voltage effective values, a plurality of controller three-phase voltage effective values and a plurality of motor three-phase current effective values;

[0008] Judging the phase loss of the motor to be tested according to a plurality of the controller bus voltage effective values, a plurality of the controller three-phase voltage effective values and a plurality of the motor three-phase current effective values to obtain a phase loss detection result.

[0009] Optionally, the judging the phase loss of the motor to be tested according to a plurality of the controller bus voltage effective values, a plurality of the controller three-phase voltage effective values and a plurality of the motor three-phase current effective values to obtain a phase loss detection result includes:

[0010] Calculate the unbalance degree based on the effective values of the three-phase voltages of multiple said controllers and the effective values of the three-phase currents of multiple said motors to obtain the three-phase voltage unbalance degree and the three-phase current unbalance degree;

[0011] Calculate the fluctuation of the bus based on the effective value of the bus voltage of multiple said controllers to obtain the bus fluctuation value;

[0012] When the bus fluctuation value is greater than the preset fluctuation value and the three-phase voltage unbalance degree is greater than the balance degree threshold, the phase loss detection result is that the input terminal controller is missing a phase;

[0013] When the three-phase current unbalance degree is greater than the balance degree threshold, the phase loss detection result is that the output terminal motor is missing a phase.

[0014] Optionally, the three-phase voltage unbalance degree includes the controller UV unbalance degree between the controller U phase and the controller V phase, the controller UW unbalance degree between the controller U phase and the controller W phase, and the controller VW unbalance degree between the controller V phase and the controller W phase; after the phase loss detection result is that the input terminal controller is missing a phase when the bus fluctuation value is greater than the preset fluctuation value and the three-phase voltage unbalance degree is greater than the balance degree threshold, it further includes:

[0015] When both the controller UV unbalance degree and the controller UW unbalance degree are greater than the balance degree threshold, the phase loss detection result is that the input terminal controller U phase is missing a phase;

[0016] When both the controller UV unbalance degree and the controller VW unbalance degree are greater than the balance degree threshold, the phase loss detection result is that the input terminal controller V phase is missing a phase;

[0017] When both the controller VW unbalance degree and the controller UW unbalance degree are greater than the balance degree threshold, the phase loss detection result is that the input terminal controller W phase is missing a phase.

[0018] Optionally, the three-phase current unbalance degree includes the motor UV unbalance degree between the motor U phase and the motor V phase, the motor UW unbalance degree between the motor U phase and the motor W phase, and the motor VW unbalance degree between the motor V phase and the motor W phase; after the phase loss detection result is that the output terminal motor is missing a phase when the three-phase current unbalance degree is greater than the balance degree threshold, it further includes:

[0019] When both the motor UV unbalance degree and the motor UW unbalance degree are greater than the balance degree threshold, the phase loss detection result is that the motor U phase is missing a phase;

[0020] When both the UV unbalance degree of the motor and the VW unbalance degree of the motor are greater than the balance degree threshold, the open-phase detection result is that the V phase of the motor is open-phased;

[0021] When both the VW unbalance degree of the motor and the UW unbalance degree of the motor are greater than the balance degree threshold, the open-phase detection result is that the W phase of the motor is open-phased.

[0022] Optionally, before obtaining the controller bus voltage, the controller three-phase voltage, and the motor three-phase current of the motor to be measured for any period of time, it further includes:

[0023] Obtain the target bus voltage, the target three-phase voltage, and the target three-phase current before applying high voltage to the motor to be measured;

[0024] Perform high-frequency filtering processing on the target bus voltage, the target three-phase voltage, and the target three-phase current respectively to obtain the corresponding bus voltage zero-drift calibration value, three-phase voltage zero-drift calibration value, and three-phase current zero-drift calibration value.

[0025] Optionally, the preprocessing of the controller bus voltage, the controller three-phase voltage, and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values includes:

[0026] Use the bus voltage zero-drift calibration value, the three-phase voltage zero-drift calibration value, and the three-phase current zero-drift calibration value to perform zero-drift calibration on the controller bus voltage, the controller three-phase voltage, and the motor three-phase current respectively to obtain multiple controller bus voltage calibration values, multiple controller three-phase voltage calibration values, and multiple motor three-phase current calibration values;

[0027] Take the absolute values of multiple controller bus voltage calibration values, multiple controller three-phase voltage calibration values, and multiple motor three-phase current calibration values to obtain the corresponding multiple bus voltage absolute values, multiple three-phase voltage absolute values, and multiple three-phase current absolute values;

[0028] Perform low-pass filtering processing on multiple bus voltage absolute values, multiple three-phase voltage absolute values, and multiple three-phase current absolute values according to a preset low-pass filtering formula to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values.

[0029] Optionally, after performing open-phase judgment on the motor to be measured based on multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values to obtain an open-phase detection result, it further includes:

[0030] When the open-phase detection result includes at least one of controller open-phase or motor open-phase, obtain the torque fluctuation amount;

[0031] Determine whether the torque fluctuation amount is within a preset range;

[0032] When the torque fluctuation amount is not within the preset range, confirm that the open-phase detection result is correct;

[0033] When the torque fluctuation amount is within the preset range, confirm that the open-phase detection result is incorrect.

[0034] Optionally, after confirming that the open-phase detection result is correct when the torque fluctuation amount is not within the preset range, it further includes:

[0035] Start timing from when it is confirmed that the open-phase detection result is correct, and issue an open-phase protection instruction when the timing time is greater than the preset time;

[0036] When the open-phase detection result is that the motor is normal, stop timing and clear the timing time to zero.

[0037] Furthermore, the present invention also provides a motor open-phase detection device, including:

[0038] A signal acquisition module, configured to acquire the controller bus voltage, the controller three-phase voltage, and the motor three-phase current of the motor to be measured within any period of time;

[0039] A signal processing module preprocesses the controller bus voltage, the controller three-phase voltage, and the motor three-phase current to obtain a plurality of controller bus voltage effective values, a plurality of controller three-phase voltage effective values, and a plurality of motor three-phase current effective values;

[0040] An open-phase judgment module is configured to perform open-phase judgment on the motor to be measured according to a plurality of the controller bus voltage effective values, a plurality of the controller three-phase voltage effective values, and a plurality of the motor three-phase current effective values to obtain an open-phase detection result.

[0041] Furthermore, the present invention also provides an electronic device, including a memory and a processor, wherein the memory is used to store a program;

[0042] The processor is coupled to the memory and is configured to execute the program stored in the memory to implement the steps in the motor open-phase detection method described in any one of the above.

[0043] The beneficial effects of the present invention are as follows: The motor phase-loss detection method provided by the present invention obtains the controller bus voltage, the controller three-phase voltage, and the motor three-phase current of the motor to be measured within any period of time; preprocesses the controller bus voltage, the controller three-phase voltage, and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values; and performs a phase-loss judgment on the motor to be measured based on the multiple controller bus voltage effective values, the multiple controller three-phase voltage effective values, and the multiple motor three-phase current effective values to obtain a phase-loss detection result. By performing an absolute value process on the acquired electrical signals and converting them into effective values, and using the effective values for phase-loss judgment, the electrical signals in any period of time can be used as the judgment basis, without having to control the motor operation cycle, that is: as long as there are electrical signals in the motor, phase-loss detection can be performed without the motor running or running at a low speed, realizing the phase-loss detection of low-speed or unstarted motors. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative efforts.

[0045] Figure 1 It is a schematic flowchart of an embodiment of the motor phase-loss detection method provided by the present invention;

[0046] Figure 2 It is a schematic flowchart of an embodiment of step S101 of the motor phase-loss detection method provided by the present invention;

[0047] Figure 3 It is a schematic flowchart of an embodiment before step S101 of the motor defect detection method provided by the present invention;

[0048] Figure 4 It is a schematic flowchart of an embodiment of step S102 of the motor phase-loss detection method provided by the present invention;

[0049] Figure 5 It is a schematic flowchart of an embodiment after step S103 of the motor phase-loss detection method provided by the present invention;

[0050] Figure 6 It is a schematic structural diagram of an embodiment of the motor phase-loss detection device provided by the present invention;

[0051] Figure 7 It is a schematic structural diagram of an embodiment of the electronic device provided by the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0052] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative efforts belong to the protection scope of the present invention.

[0053] It should be understood that the schematic drawings are not drawn to scale. The flowcharts used in the present invention illustrate the operations implemented according to some embodiments of the present invention. It should be understood that the operations in the flowchart may not be implemented in sequence, and steps without logical context relationships may be reversed or implemented simultaneously. In addition, those skilled in the art can add one or more other operations to the flowchart or remove one or more operations from the flowchart under the guidance of the content of the present invention.

[0054] Referring to "embodiment" herein means that a specific feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the present invention. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0055] The embodiments of the present invention provide a method, device, and electronic device for detecting motor phase loss, which will be described separately below.

[0056] Figure 1 It is a schematic flowchart of an embodiment of the method for detecting motor phase loss provided by the present invention, as Figure 1 shown, which includes:

[0057] S101. Obtain the controller bus voltage, controller three-phase voltage, and motor three-phase current of the motor to be tested within any period of time;

[0058] S102. Preprocess the controller bus voltage, controller three-phase voltage, and motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values;

[0059] S103. Perform a phase loss judgment on the motor to be tested according to the multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values to obtain a phase loss detection result.

[0060] It should be noted that in the embodiments of the present invention, the bus input voltage of the motor controller can be monitored in real time through the bus voltage sampling circuit, and the current in the resistor connected in parallel with the filter capacitor is collected through the three-phase output current sampling circuit. According to the collected current value and the resistance value of the parallel resistor, the three-phase output voltage of the motor controller is obtained. The three-phase output voltage collected during a period of time is the controller three-phase voltage, and the bus input voltage during a period of time is the controller bus voltage.

[0061] It can be understood that in the embodiments of the present invention, according to Kirchhoff's current law, the algebraic sum of the currents at the center point of the three-phase current is zero. When only one phase of the motor fails, the algebraic sum of the currents at the center point is still zero, that is, when the motor drive controller is normal, the three-phase current of the drive motor is always zero. Therefore, only the effective value within one current cycle of the motor to be tested needs to be collected. When the effective value of a certain phase of the drive motor is approximately zero, it can be determined that this phase is open-phase. The three-phase current of the motor is the value of the three-phase current of the drive motor collected during a period of time; however, both the voltage cycle and the current cycle are related to the speed and are constantly changing. It is very difficult to accurately collect one cycle of an electrical signal in actual detection. Therefore, the present invention monitors the bus voltage of the motor drive controller, the three-phase output terminal voltage, and the three-phase current of the drive motor in real time. When performing open-phase detection, the bus voltage, the three-phase output terminal voltage, and the three-phase current within a period of time are obtained, and absolute value processing is performed to convert the collected AC signal into a DC signal, and the DC signal is used to represent the effective value of the electrical signal, and the open-phase of the motor is judged based on the effective value, so that the electrical signal in any time period can be used as a judgment basis, and it is not necessary to control the motor operation cycle to realize the open-phase detection of a low-speed or unstarted motor.

[0062] Compared with the prior art, the motor open-phase detection method provided by the present invention obtains the controller bus voltage, the controller three-phase voltage, and the motor three-phase current of the motor to be tested in a preset state within any period of time; performs absolute value processing and zero-drift prevention processing on the controller bus voltage, the controller three-phase voltage, and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values; judges the open-phase of the motor to be tested based on the multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values to obtain the open-phase detection result. The present invention performs absolute value processing on the obtained electrical signal, converts it into an effective value, and uses the effective value to judge the open-phase, so that the electrical signal in any time period can be used as a judgment basis, and it is not necessary to control the motor operation cycle, realizing the open-phase detection of a low-speed or unstarted motor. The present invention also calibrates the obtained data through zero-drift prevention processing, improving the accuracy of motor open-phase detection.

[0063] Refer to Figure 2 , Figure 2Schematic diagram of the process of an embodiment of step S101 of the motor open-phase detection method provided by the present invention. In some embodiments of the present invention, step S103 includes:

[0064] S201. Calculate the unbalance degree based on the effective values of the three-phase voltages of multiple controllers and the effective values of the three-phase currents of multiple motors to obtain the three-phase voltage unbalance degree and the three-phase current unbalance degree;

[0065] S202. Calculate the fluctuation of the bus based on the effective value of the bus voltage of multiple controllers to obtain the bus fluctuation value;

[0066] S203. When the bus fluctuation value is greater than the preset fluctuation value and the three-phase voltage unbalance degree is greater than the balance degree threshold, the open-phase detection result is that the input-end controller is open-phase;

[0067] S204. When the three-phase current unbalance degree is greater than the balance degree threshold, the open-phase detection result is that the output-end motor is open-phase.

[0068] It can be understood that in the embodiments of the present invention, the bus fluctuation value is the difference between the maximum value and the minimum value of the collected controller bus voltage. By comparing this difference with the preset fluctuation value, it can be determined whether the bus fluctuation is within the controllable range. When the bus fluctuation is not within the controllable range (that is, the controller bus voltage fluctuates greatly), it indicates that the motor controller may be open-phase. If at this time the unbalance degree among the three-phase voltages of the controller is greater than the balance degree threshold, it indicates that the motor controller has an open-phase fault; when there is a value greater than the balance degree threshold among the three-phase current unbalance degrees, it indicates that the drive motor has an open-phase fault.

[0069] In some embodiments of the present invention, the three-phase voltage unbalance degree includes the controller UV unbalance degree between the controller U phase and the controller V phase, the controller UW unbalance degree between the controller U phase and the controller W phase, and the controller VW unbalance degree between the controller V phase and the controller W phase. After step S202, it further includes:

[0070] When both the controller UV unbalance degree and the controller UW unbalance degree are greater than the balance degree threshold, the open-phase detection result is that the input-end controller U phase is open-phase;

[0071] When both the controller UV unbalance degree and the controller VW unbalance degree are greater than the balance degree threshold, the open-phase detection result is that the input-end controller V phase is open-phase;

[0072] When both the controller VW unbalance degree and the controller UW unbalance degree are greater than the balance degree threshold, the open-phase detection result is that the input-end controller W phase is open-phase.

[0073] It can be understood that in this embodiment, the three phases of the AC clock are generally divided into the U phase, the V phase, and the W phase. The collected controller bus voltage can be taken as UC , the three-phase output voltages of the motor drive controller are U U , U V and U W , and the three-phase currents of the drive motor are I U , I V , I W ; Take the absolute values of the above-acquired electrical signals respectively and form a bus voltage curve U C_flt , a U-phase voltage curve U U_flt , a V-phase voltage curve U V_flt , a W-phase voltage curve U W_flt , a U-phase current curve I U_flt , a V-phase current curve I V_flt and a W-phase current curve I W_flt ; Calculate the unbalance degrees of the three phases pairwise to obtain the controller UV unbalance degree U D_UV between the controller U-phase and the controller V-phase, the controller UW unbalance degree U D_UW between the controller U-phase and the controller W-phase, the controller VW unbalance degree U D_VW between the controller V-phase and the controller W-phase, the motor UV unbalance degree I D_UV between the motor U-phase and the motor V-phase, the motor UW unbalance degree I D_UW between the motor U-phase and the motor W-phase, and the motor VW unbalance degree I D_VW between the motor V-phase and the motor W-phase; Taking the UV two phases of the three-phase current of the drive motor as an example, its unbalance degree calculation formula is Taking the UV two phases of the three-phase voltage of the drive controller as an example, its unbalance degree calculation formula is

[0074] It can be understood that in this embodiment, the effective values of the three-phase output voltages of the drive controller should be equal. When there is an obvious difference (i.e., unbalance) between the effective values of the three-phase output voltages, it indicates that a fault has occurred in the drive motor; For example: when the U-phase of the drive motor is open-phase, U D_UV ≥ DOU and U D_UW ≥ DOU, this DOU is the smoothness threshold. In this embodiment, this smoothness threshold is taken as 90%, and it can be specifically selected according to requirements. This embodiment does not limit this; The present invention detects open-phase by the unbalance degree between the three-phase output voltages of the drive controller, and can not only accurately detect whether the drive controller is open-phase, but also quickly determine which phase has an open-phase fault, realizing accurate positioning of the fault phase.

[0075] In some embodiments of the present invention, the three-phase current unbalance includes the motor UV unbalance between the U phase and the V phase of the motor, the motor UW unbalance between the U phase and the W phase of the motor, and the motor VW unbalance between the V phase and the W phase of the motor. After step S203, the method further includes:

[0076] When both the motor UV unbalance and the motor UW unbalance are greater than the balance threshold, the phase loss detection result is that the U phase of the motor is missing.

[0077] When both the motor UV unbalance and the motor VW unbalance are greater than the balance threshold, the phase loss detection result is that the V phase of the motor is missing.

[0078] When both the motor VW unbalance and the motor UW unbalance are greater than the balance threshold, the phase loss detection result is that the W phase of the motor is missing.

[0079] It can be understood that since the amplitudes of the three-phase currents are the same (i.e., the effective values are equal), in the normal operating state, I U_flt 、I V_flt 、I W_flt of the driving motor are approximately equal. If a phase loss fault occurs in the driving motor, a current value of 0 will appear in I U_flt 、I V_flt 、I W_flt . At this time, the three-phase currents are unbalanced. Therefore, the three-phase current unbalance can be used to determine whether the driving motor is missing a phase. For example: when the driving controller is normal but the U phase of the driving motor is missing, I D_UV ≥DOU and I D_UW ≥DOU, but at this time U D_UV <DOU and U D_UW <DOU; this is one of the fault situations. The specific position of the phase loss fault can be accurately confirmed by the above method for any phase loss situation of the driving controller and the driving motor, so as to be repaired in time. This embodiment will not be elaborated here.

[0080] Referring to Figure 3 , Figure 3 is a schematic flow chart of an embodiment before step S101 of the motor defect detection method provided by the present invention; in some embodiments of the present invention, before step S101, the method further includes:

[0081] S301. Obtain the target bus voltage, target three-phase voltage, and target three-phase current before applying high voltage to the motor to be tested;

[0082] S302. Perform high-frequency filtering processing on the target bus voltage, the target three-phase voltage, and the target three-phase current respectively to obtain the corresponding bus voltage zero-drift calibration value, three-phase voltage zero-drift calibration value, and three-phase current zero-drift calibration value.

[0083] It can be understood that in the acquisition of electrical signals, the acquired electrical signals are prone to zero drift. Therefore, it is necessary to perform zero-drift prevention processing on the acquired electrical signals to reduce signal errors and improve the accuracy of motor open-phase detection. In the embodiments of the present invention, by performing real-time acquisition of electrical signals before connecting high voltage to the motor to be tested, the controller bus voltage (i.e., the high-voltage bus voltage), the controller three-phase output voltage (i.e., the high-voltage three-phase voltage), and the drive motor three-phase current (i.e., the high-voltage three-phase current) are obtained. When performing open-phase detection on the motor to be tested, high voltage needs to be connected. At this time, the last acquired electrical signal before connecting high voltage to the motor to be tested can be obtained from the above-acquired electrical signals as the target bus voltage, the target three-phase voltage, and the target three-phase current, and then the acquired signals are filtered to remove high-frequency clutter, obtaining relatively stable bus voltage zero-drift calibration values, three-phase voltage zero-drift calibration values, and three-phase current zero-drift calibration values.

[0084] It should be understood that in this embodiment, a low-pass filter can be used for filtering processing. The theoretical formula of this low-pass filter is:

[0085] y(t) = K * u(t) + (1 - K) * y(t - 1) = y(t - 1) + K * [u(t) - y(t - 1)];

[0086] Among them, in the formula K generally ranges between 0 and 1, dT is the running step, T is the time constant, u is the input signal, and y is the output signal. In this embodiment, dT = 0.1 ms, T = 0.0053, and the running step and the time constant can be set according to actual requirements, and this embodiment does not limit this.

[0087] Referring to Figure 4 , Figure 4 is a schematic flowchart of an embodiment of step S102 of the motor open-phase detection method provided by the present invention. In some embodiments of the present invention, step S102 includes:

[0088] S401. Use the bus voltage zero-drift calibration value, the three-phase voltage zero-drift calibration value, and the three-phase current zero-drift calibration value to perform zero-drift calibration on the controller bus voltage, the controller three-phase voltage, and the motor three-phase current respectively, obtaining multiple controller bus voltage calibration values, multiple controller three-phase voltage calibration values, and multiple motor three-phase current calibration values;

[0089] S402. Take the absolute values of the multiple controller bus voltage calibration values, the multiple controller three-phase voltage calibration values, and the multiple motor three-phase current calibration values, obtaining the corresponding multiple bus voltage absolute values, multiple three-phase voltage absolute values, and multiple three-phase current absolute values;

[0090] S403. Perform low-pass filtering on multiple absolute values of bus voltages, multiple absolute values of three-phase voltages, and multiple absolute values of three-phase currents according to a preset low-pass filtering formula to obtain multiple effective values of controller bus voltages, multiple effective values of controller three-phase voltages, and multiple effective values of motor three-phase currents.

[0091] It can be understood that in the embodiments of the present invention, by subtracting the zero-drift calibration value of the bus voltage from each value in the controller bus voltage, subtracting the zero-drift calibration value of the three-phase voltage from each value in the controller three-phase voltage, and subtracting the zero-drift calibration value of the three-phase current from each value in the motor three-phase current, anti-zero-drift processing is performed to eliminate the error of the collected electrical signal and improve the detection accuracy of the open-phase fault; the low-pass filtering formula can refer to the theoretical formula of the above low-pass filter.

[0092] Refer to Figure 5 , Figure 5 is a schematic flowchart of an embodiment after step S103 of the motor open-phase detection method provided by the present invention; in some embodiments of the present invention, after step S103, it further includes:

[0093] S501. When the open-phase detection result includes at least one of controller open-phase or motor open-phase, obtain the torque fluctuation amount;

[0094] S502. Determine whether the torque fluctuation amount is within a preset range;

[0095] S503. When the torque fluctuation amount is not within the preset range, confirm that the open-phase detection result is correct;

[0096] S504. When the torque fluctuation amount is within the preset range, confirm that the open-phase detection result is incorrect.

[0097] It can be understood that when an open-phase fault occurs, the torque fluctuation of the motor will also increase. Therefore, in order to enhance the reliability of the open-phase fault detection, torque fluctuation detection is introduced. By determining whether the torque fluctuation amount is within a preset range, the open-phase fault detection result is confirmed; in a specific implementation, the running step size can be set to 0.1 ms, that is, a torque value is collected every 0.1 ms. The torque fluctuation amount can be calculated through the collected torque value and the torque fluctuation amount formula; the formula for the torque fluctuation amount TD is as follows:

[0098]

[0099] where T e is the current torque value and T ref is the torque set value.

[0100] It is stipulated that when the torque steady-state control accuracy is at T ref ≤100 Nm, the fluctuation range of the actual torque T e is Tref ±3 Nm; T ref When it is greater than 100 Nm, the actual torque T e The fluctuation range of is (1 ± 3%)T ref Therefore, the judgment conditions for simplifying torque fluctuation are as follows:

[0101]

[0102] That is, T D should be within the above range. If not, it indicates a single-phase loss fault has occurred.

[0103] In some embodiments of the present invention, after step S503, it further includes:

[0104] Start timing from when the single-phase loss detection result is confirmed to be correct, and issue a single-phase loss protection instruction when the timing time is greater than the preset time;

[0105] When the single-phase loss detection result is that the motor is normal, stop timing and clear the timing time to zero.

[0106] It can be understood that to prevent misjudgment, for example, when the motor is blocked, as the position angle of the motor rotor is different, the drive motor may output three-phase DC currents of uncertain magnitudes; or when the rotor position angle is 90 degrees, the current enters the motor from the V phase and exits the motor from the W phase. At this time, the U-phase current is 0, and the U phase will falsely report a single-phase loss fault; or when the motor speed is very slow and it is too late to sample the current for one cycle, if most of the sampling points are near point A, it may also falsely report a single-phase loss fault in the U phase. Therefore, to prevent false alarms from triggering the protection mechanism, start timing after confirming that the single-phase loss detection result is correct, issue a single-phase loss protection instruction when the timing time is greater than the preset time, stop timing and clear the timing time to zero when the single-phase loss detection result is that the motor is normal. The preset time can be set to 50 ms and can be set according to the actual situation. This embodiment does not limit this.

[0107] Refer to Figure 6 Figure 6 is a schematic structural diagram of an embodiment of the motor single-phase loss detection device provided by the present invention.

[0108] This embodiment also provides a motor single-phase loss detection device, and this device includes:

[0109] A signal acquisition module 601, configured to acquire the controller bus voltage, controller three-phase voltage, and motor three-phase current of the motor to be measured for any period of time;

[0110] A signal processing module 602, configured to preprocess the controller bus voltage, controller three-phase voltage, and motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values; ​

[0111] A phase loss judgment module 603 is configured to perform phase loss judgment on a motor to be measured according to the effective values of the bus voltages of multiple controllers, the effective values of the three-phase voltages of multiple controllers, and the effective values of the three-phase currents of multiple motors, so as to obtain a phase loss detection result.

[0112] The motor phase loss detection device provided in the above embodiment can implement the solution described in the above embodiment of the motor phase loss detection method. The specific principles of the above units can be referred to the embodiment of the motor phase loss detection method, which will not be elaborated here.

[0113] Refer to Figure 7 Furthermore, the present invention also provides an electronic device 700, which includes a processor 701, a memory 702, and a display 703. Figure 7 Only some components of the electronic device 700 are shown, but it should be understood that it is not required to implement all the shown components, and more or fewer components can be alternatively implemented.

[0114] In some embodiments, the processor 701 may be a central processing unit (CPU), a microprocessor, or other data processing chips, and is configured to run program codes stored in the memory 702 or process data, such as the motor phase loss detection method in the present invention.

[0115] In some embodiments, the processor 701 may be a single server or a server group. The server group may be centralized or distributed. In some embodiments, the processor 701 may be local or remote. In some embodiments, the processor 701 may be implemented on a cloud platform. In one embodiment, the cloud platform may include a private cloud, a public cloud, a hybrid cloud, a community cloud, a distributed cloud, an internal cloud, a multi-cloud, etc., or any combination of the above.

[0116] In some embodiments, the memory 702 may be an internal storage unit of the electronic device 700, such as the hard disk or memory of the electronic device 700. In some other embodiments, the memory 702 may also be an external storage device of the electronic device 700, such as a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. equipped on the electronic device 700.

[0117] Furthermore, the memory 702 may further include both the internal storage unit and the external storage device of the electronic device 700. The memory 702 is used to store the application software installed in the electronic device 700 and various types of data.

[0118] The display 703 can be an LED display, a liquid crystal display, a touch liquid crystal display, an OLED (Organic Light-Emitting Diode) touch screen, etc. in some embodiments. The display 703 is used to display information in the electronic device 700 and to display a visual user interface. The components 701-703 of the electronic device 700 communicate with each other via a system bus.

[0119] In one embodiment, when the processor 701 executes the motor phase loss detection program in the memory 702, the following steps can be implemented:

[0120] Obtain the controller bus voltage, the controller three-phase voltage, and the motor three-phase current under the preset state of the motor to be tested for any period of time;

[0121] Perform absolute value processing and zero-drift prevention processing on the controller bus voltage, the controller three-phase voltage, and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values;

[0122] Perform a phase loss judgment on the motor to be tested based on the multiple controller bus voltage effective values, multiple controller three-phase voltage effective values, and multiple motor three-phase current effective values to obtain a phase loss detection result.

[0123] It should be understood that when the processor 701 executes the program in the memory 702, in addition to the above functions, other functions can also be implemented. For specific details, please refer to the description of the corresponding method embodiments above.

[0124] Furthermore, the embodiments of the present invention do not specifically limit the type of the electronic device 700 mentioned. The electronic device 700 can be a portable electronic device such as a mobile phone, a tablet computer, a personal digital assistant (PDA), a wearable device, a laptop computer, etc. Exemplary embodiments of the portable electronic device include, but are not limited to, portable electronic devices running IOS, android, microsoft, or other operating systems. The above portable electronic devices can also be other portable electronic devices, such as a laptop computer with a touch-sensitive surface (such as a touch panel). It should also be understood that in some other embodiments of the present invention, the electronic device 700 may not be a portable electronic device, but a desktop computer with a touch-sensitive surface (such as a touch panel).

[0125] Those skilled in the art can understand that all or part of the processes of implementing the methods of the above embodiments can be completed by instructing relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. Among them, the computer-readable storage medium is a disk, an optical disc, a read-only memory, or a random access memory, etc.

[0126] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention.

Claims

1. A method for detecting a motor phase loss, characterized in that: include: Obtain the controller bus voltage, controller three-phase voltage and motor three-phase current of the motor to be tested within any period of time; Preprocessing the controller bus voltage, the controller three-phase voltage and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values ​​and multiple motor three-phase current effective values; the preprocessing includes performing absolute value processing on the controller bus voltage, the controller three-phase voltage and the motor three-phase current, converting the collected AC signal into a DC signal, and using the DC signal to represent the effective value of the electrical signal; According to multiple effective values ​​of the bus voltage of the controller, multiple effective values ​​of the three-phase voltage of the controller and multiple effective values ​​of the three-phase current of the motor, the phase loss detection result of the motor to be tested is judged, and the phase loss detection result is obtained; according to multiple effective values ​​of the bus voltage of the controller, multiple effective values ​​of the three-phase voltage of the controller and multiple effective values ​​of the three-phase current of the motor, the phase loss detection result of the motor to be tested is judged, including: Calculate the imbalance degree according to the effective values ​​of the three-phase voltages of the controller and the effective values ​​of the three-phase currents of the motor to obtain the three-phase voltage imbalance degree and the three-phase current imbalance degree; Calculating bus fluctuations according to multiple bus voltage effective values ​​of the controllers to obtain bus fluctuation values; When the bus fluctuation value is greater than the preset fluctuation value and the three-phase voltage imbalance is greater than the balance threshold, the phase loss detection result is that the input end controller is phase-lost; When the three-phase current unbalance is greater than the balance threshold, the phase loss detection result is that the output end motor is phase-lost; The three-phase voltage imbalance includes the controller UV imbalance between the controller U phase and the controller V phase, the controller UW imbalance between the controller U phase and the controller W phase, and the controller VW imbalance between the controller V phase and the controller W phase; the three-phase current imbalance includes the motor UV imbalance between the motor U phase and the motor V phase, the motor UW imbalance between the motor U phase and the motor W phase, and the motor VW imbalance between the motor V phase and the motor W phase.

2. The motor phase loss detection method according to claim 1, characterized in that: When the bus fluctuation value is greater than the preset fluctuation value and the three-phase voltage imbalance is greater than the balance threshold, the phase loss detection result is that the input end controller is phase-lost, the method further includes: When the controller UV imbalance and the controller UW imbalance are both greater than the balance threshold, the phase loss detection result is that the input end controller U phase is lost; When the controller UV imbalance and the controller VW imbalance are both greater than the balance threshold, the phase loss detection result is that the input end controller V phase is lost; When the controller VW imbalance and the controller UW imbalance are both greater than the balance threshold, the phase loss detection result is that the input end controller W phase is lost.

3. The motor phase loss detection method according to claim 1, characterized in that: When the three-phase current imbalance is greater than the balance threshold, the phase loss detection result is that the output end motor is phase-lost, the method further includes: When the motor UV imbalance and the motor UW imbalance are both greater than the balance threshold, the phase loss detection result is that the motor U phase is lost; When the motor UV imbalance and the motor VW imbalance are both greater than the balance threshold, the phase loss detection result is that the motor V phase is lost; When the motor VW imbalance and the motor UW imbalance are both greater than the balance threshold, the phase loss detection result is that the motor W phase is lost.

4. The motor phase loss detection method according to claim 1, characterized in that: Before obtaining the controller bus voltage, the controller three-phase voltage and the motor three-phase current of the motor to be tested within any period of time, the method further includes: Obtaining the target bus voltage, target three-phase voltage and target three-phase current before high voltage on the motor to be tested; The target bus voltage, the target three-phase voltage and the target three-phase current are respectively subjected to high-frequency filtering processing to obtain corresponding bus voltage zero-drift calibration values, three-phase voltage zero-drift calibration values ​​and three-phase current zero-drift calibration values.

5. The motor phase loss detection method according to claim 4, characterized in that: The preprocessing of the controller bus voltage, the controller three-phase voltage and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values ​​and multiple motor three-phase current effective values ​​includes: The bus voltage zero drift calibration value, the three-phase voltage zero drift calibration value and the three-phase current zero drift calibration value are used to perform zero drift calibration on the controller bus voltage, the controller three-phase voltage and the motor three-phase current respectively, to obtain multiple controller bus voltage calibration values, multiple controller three-phase voltage calibration values ​​and multiple motor three-phase current calibration values; Taking absolute values ​​of a plurality of the controller bus voltage calibration values, a plurality of the controller three-phase voltage calibration values ​​and a plurality of the motor three-phase current calibration values ​​to obtain corresponding plurality of bus voltage absolute values, a plurality of three-phase voltage absolute values ​​and a plurality of three-phase current absolute values; According to a preset low-pass filtering formula, low-pass filtering is performed on multiple bus voltage absolute values, multiple three-phase voltage absolute values ​​and multiple three-phase current absolute values ​​to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values ​​and multiple motor three-phase current effective values.

6. The motor phase loss detection method according to claim 1, characterized in that: After determining the phase failure of the motor to be tested based on the multiple effective values ​​of the controller bus voltage, the multiple effective values ​​of the controller three-phase voltage and the multiple effective values ​​of the motor three-phase current, and obtaining the phase failure detection result, the method further includes: When the phase loss detection result includes at least one of a controller phase loss or a motor phase loss, obtaining a torque fluctuation amount; Determining whether the torque fluctuation amount is within a preset range; When the torque fluctuation amount is not within a preset range, confirming that the phase loss detection result is correct; When the torque fluctuation amount is within a preset range, it is confirmed that the phase loss detection result is wrong.

7. The motor phase loss detection method according to claim 6, characterized in that: When the torque fluctuation amount is not within the preset range, after confirming that the phase loss detection result is correct, the method further includes: Start timing when the phase loss detection result is confirmed to be correct, and issue a phase loss protection instruction when the timing time is greater than a preset time; When the phase loss detection result shows that the motor is normal, the timing is stopped and the timing time is reset to zero.

8. A motor phase loss detection device, used for performing phase loss detection on a three-phase motor according to the motor phase loss detection method according to any one of claims 1 to 7, characterized in that: include: A signal acquisition module is used to obtain the controller bus voltage, controller three-phase voltage and motor three-phase current of the motor to be tested within any period of time; A signal processing module pre-processes the controller bus voltage, the controller three-phase voltage and the motor three-phase current to obtain multiple controller bus voltage effective values, multiple controller three-phase voltage effective values ​​and multiple motor three-phase current effective values; The phase loss judgment module is used to judge the phase loss of the motor to be tested according to multiple effective values ​​of the controller bus voltage, multiple effective values ​​of the controller three-phase voltage and multiple effective values ​​of the motor three-phase current to obtain a phase loss detection result.

9. An electronic device, characterized in that: The method comprises a memory and a processor, wherein the memory is used to store a program; The processor is coupled to the memory and is used to execute the program stored in the memory to implement the steps in the motor phase loss detection method described in any one of claims 1 to 7.

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