Motor open-phase detection method and device, motor equipment and storage medium

Abstract

The invention relates to the technical field of motor detection, and discloses a motor open-phase detection method and device, motor equipment and a storage medium, and the method comprises the steps: collecting the three-phase current corresponding to a motor, obtaining the current motor load rate and environment temperature, accumulating the absolute value of each phase of current collected in a preset time period, and obtaining the accumulated value of each phase of current, determining a default-phase preset coefficient based on the current motor load rate and the environment temperature, determining a current judgment threshold based on the default-phase preset coefficient, the number of current acquisition times in a preset time period and a preset unit current value, and when the current accumulated value of any phase is smaller than the current judgment threshold, determining that the motor has a default-phase fault. The three-phase current is collected and subjected to accumulation statistics, and the coefficient threshold value set by the real-time working condition of the motor is combined, so that the open-phase fault of the motor is quickly and accurately judged, a generator protection mechanism can be triggered in time, and the motor is prevented from being damaged due to open-phase.

Description

Technical Field

[0001] This invention relates to the field of motor testing technology, specifically to a method, apparatus, motor equipment, and storage medium for detecting motor phase loss. Background Technology

[0002] As the core power source in industrial and household equipment, motors are widely used in various machinery, automation systems, and household appliances. Their operating status directly affects the stability, efficiency, and service life of the equipment. However, in actual operation, a motor may experience a phase loss fault due to reasons such as power line failure, fuse blowout, poor contact, or external environmental interference, causing one phase of the three-phase power supply to disconnect. If the phase loss fault of the motor cannot be determined in time or accurately, the motor protection may not be triggered in time. Phase loss operation can lead to motor current imbalance, temperature rise, efficiency reduction, wear or damage to mechanical parts, and even motor burnout or fire. Summary of the Invention

[0003] In view of this, the present invention provides a method, apparatus, motor equipment and storage medium for detecting motor phase loss, in order to solve the problem that defects and faults can affect the operation of motor equipment and cause safety accidents.

[0004] In a first aspect, the present invention provides a method for detecting a phase loss in a motor. The method includes: acquiring the three-phase current corresponding to the motor, and obtaining the current motor load rate and ambient temperature; accumulating the absolute values ​​of the current of each phase acquired within a preset time period to obtain an accumulated value of the current of each phase; determining a phase loss preset coefficient based on the current motor load rate and ambient temperature; determining a current judgment threshold based on the phase loss preset coefficient, the number of current acquisitions within the preset time period, and a preset unit current value; and determining a phase loss fault in the motor when the accumulated value of any phase current is less than the current judgment threshold.

[0005] The motor phase loss detection method provided in this embodiment collects the three-phase current of the motor, as well as the current motor load rate and ambient temperature. It accumulates the absolute values ​​of the current of each phase collected within a preset time period to obtain the accumulated value of the current of each phase. Based on the current motor load rate and ambient temperature, a phase loss preset coefficient is determined. Based on the phase loss preset coefficient, the number of current acquisitions within the preset time period, and a preset unit current value, a current judgment threshold is determined. When the accumulated value of any phase current is less than the current judgment threshold, a motor phase loss fault is determined. By collecting and accumulating the three-phase current, combined with the coefficient threshold set for the real-time operating conditions of the motor, a rapid and accurate judgment of motor phase loss faults can be achieved, and the motor protection mechanism can be triggered in a timely manner to avoid damage to the motor caused by phase loss.

[0006] In one optional implementation, determining the phase loss preset coefficient based on the current motor load rate and ambient temperature includes: determining a coefficient correction value based on the current motor load rate and ambient temperature; and multiplying the coefficient correction value by the basic phase loss coefficient to obtain the phase loss preset coefficient.

[0007] This invention correlates the coefficient correction value with the load rate and ambient temperature in real time, so that the phase loss preset coefficient is dynamically adjusted according to the motor operating conditions, thereby improving the adaptability and stability of phase loss protection under complex operating conditions.

[0008] In one optional implementation, determining the coefficient correction value based on the current motor load rate and ambient temperature includes: dividing the current motor load rate by the rated load rate to obtain a load deviation coefficient; multiplying the load deviation coefficient by a first preset coefficient to obtain a first correction value; subtracting a temperature standard value from the ambient temperature to obtain a temperature deviation value; dividing the temperature deviation value by the rated temperature difference value to obtain a temperature deviation coefficient; multiplying the temperature deviation coefficient by a second preset coefficient to obtain a second correction value; and determining the coefficient correction value based on the first correction value and the second correction value.

[0009] This invention quantifies the effects of load rate and temperature by multiplying the deviation coefficient by the weight, thereby improving the accuracy of coefficient determination. Furthermore, by setting correction boundaries using the rated load rate and rated temperature difference, it ensures the stability of the coefficient correction value and avoids protection malfunctions caused by parameter mutations.

[0010] In one optional implementation, the phase loss preset coefficient is calculated using the following formula:

[0011] in, Indicates the phase loss preset coefficient; Indicates the basic phase loss coefficient; Indicates the first preset coefficient; Indicates the current motor load rate; Indicates the rated load rate; Indicates the second preset coefficient; Indicates the current ambient temperature; Indicates the standard temperature value; This indicates the rated temperature difference value.

[0012] After collecting the current motor load rate and ambient temperature, this invention can directly calculate the phase loss preset coefficient based on the above formula, which can be used for subsequent motor phase loss detection. This is simple to implement and easy to put into practice, improving the efficiency of phase loss detection.

[0013] In one optional implementation, the basic phase loss coefficient is obtained through the following steps: selecting the maximum accumulated value among the three-phase current accumulated values; dividing the maximum accumulated value by the product of the number of current samplings within the preset time period and the preset unit current to obtain a first coefficient value; adding the first coefficient value to the preset basic coefficient to obtain the basic phase loss coefficient.

[0014] This invention indirectly uses the current current level of the normal phase as a reference by introducing the cumulative value of the maximum three-phase current, so that the basic phase loss coefficient and the actual three-phase current value can be dynamically set, thereby improving the accuracy and adaptability of defect detection.

[0015] In an optional implementation, before determining the current judgment threshold based on the phase loss preset coefficient, the number of current samplings within the preset time period, and the preset unit current value, the method further includes: reducing the phase loss preset coefficient when the current motor load rate is detected to be greater than a first preset load rate threshold, and / or when the ambient temperature is detected to be less than a first preset temperature threshold; or increasing the phase loss preset coefficient when the current motor load rate is detected to be less than a second preset load rate threshold, and / or when the ambient temperature is detected to be greater than a second preset temperature threshold.

[0016] This invention triggers the dynamic adjustment of the phase loss preset coefficient by using two-dimensional conditions of load rate and ambient temperature, avoiding the problems of over-protection or under-protection caused by fixed coefficients. It can prevent the extreme of phase loss protection and ensure the operational stability under different working conditions.

[0017] In one optional implementation, the acquisition of the three-phase current corresponding to the motor includes: acquiring the three-phase current corresponding to the motor based on the pulse width modulation frequency of the external drive system of the motor.

[0018] This invention synchronizes the sampling frequency with the pulse width adjustment frequency, allowing the sampled current data to reflect the gradual changes in current in real time, perfectly capturing dynamic changes in current and improving current sampling accuracy.

[0019] Secondly, the present invention provides a motor phase loss detection device, the device comprising: a data acquisition module for acquiring the three-phase current corresponding to the motor, and obtaining the current motor load rate and ambient temperature; a current accumulation module for accumulating the absolute values ​​of the current of each phase acquired within a preset time period to obtain the accumulated value of the current of each phase; a coefficient determination module for determining a phase loss preset coefficient based on the current motor load rate and ambient temperature; a current threshold calculation module for determining a current judgment threshold based on the phase loss preset coefficient, the number of current acquisitions within the preset time period, and a preset unit current value; and a motor fault determination module for determining a motor phase loss fault when the accumulated value of any phase current is less than the current judgment threshold.

[0020] Thirdly, the present invention provides a motor device, the motor device including a motor and a controller, the controller including a memory and a processor, the memory and the processor being communicatively connected to each other, the memory storing computer instructions, the processor executing the computer instructions to perform the motor phase loss detection method of the first aspect or any corresponding embodiment described above.

[0021] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to execute the motor phase loss detection method of the first aspect or any corresponding embodiment described above.

[0022] The present invention has the following technical effects: The motor phase loss detection method provided by this invention collects the three-phase current of the motor, as well as the current motor load rate and ambient temperature. The absolute values ​​of the current of each phase collected within a preset time period are accumulated to obtain the accumulated value of the current of each phase. Based on the current motor load rate and ambient temperature, a phase loss preset coefficient is determined. Based on the phase loss preset coefficient, the number of current collections within the preset time period, and a preset unit current value, a current judgment threshold is determined. When the accumulated value of any phase current is less than the current judgment threshold, a phase loss fault in the motor is determined. By collecting and accumulating the three-phase current, combined with the coefficient threshold set according to the real-time operating conditions of the motor, a rapid and accurate judgment of motor phase loss faults can be achieved, and the motor protection mechanism can be triggered in a timely manner to avoid damage to the motor caused by phase loss. Attached Figure Description

[0023] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0024] Figure 1 This is a schematic flowchart of a motor phase loss detection method according to an embodiment of the present invention; Figure 2 This is a schematic flowchart of another motor phase loss detection method according to an embodiment of the present invention; Figure 3 This is a flowchart illustrating another motor phase loss detection method according to an embodiment of the present invention; Figure 4 This is a flowchart of a motor phase loss detection method according to an embodiment of the present invention; Figure 5 This is a structural example diagram of an electric motor device according to an embodiment of the present invention; Figure 6 This is a structural block diagram of a motor phase loss detection device according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the hardware structure of the controller according to an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] According to an embodiment of the present invention, a method for detecting a phase loss in a motor is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0027] This embodiment provides a method for detecting a missing phase in a motor, which can be used in the controller of a motor device. Figure 1 This is a flowchart of a motor phase loss detection method according to an embodiment of the present invention, as shown below. Figure 1 As shown, the process includes the following steps: Step S101: Collect the three-phase current corresponding to the motor, and obtain the current motor load rate and ambient temperature.

[0028] In this embodiment of the invention, the analog-to-digital converter (ADC) of the microcontroller unit (MCU) can acquire the three-phase currents Ia, Ib, and Ic of the motor at a preset sampling frequency. The sampling frequency can be set according to the actual defect detection requirements and detection resource costs, for example, 10kHz. Alternatively, the current motor load rate can be monitored and fed back by a load sensor. The load rate is the ratio of the current power to the rated power. The ambient temperature can be monitored and fed back by a temperature sensor, which is only an example.

[0029] Step S102: The absolute values ​​of the current of each phase collected within the preset time period are accumulated to obtain the accumulated value of the current of each phase.

[0030] In this embodiment of the invention, the absolute value of the current of each phase can be taken, and the absolute values ​​of the current of each phase collected within a preset time period can be accumulated. That is, the current of each phase collected by the current collection count CheckCount within the preset time period can be accumulated to obtain the accumulated value of the current of each phase Iaaccumulated, Ibaccumulated, and Icaccumulated. The current collection count is set according to the sampling frequency and the preset time period. For example, if the sampling frequency is 10kHz and the time period is 1s to determine one phase loss, then the current collection count CheckCount is 10000.

[0031] Step S103: Determine the phase loss preset coefficient based on the current motor load rate and ambient temperature.

[0032] This invention can determine the phase loss preset coefficient K based on the current motor load rate and ambient temperature. The method for determining the phase loss preset coefficient is not limited. For example, a data table corresponding to different motor load rates, ambient temperatures, and phase loss preset coefficients can be pre-collected through multiple experiments. After obtaining the current motor load rate and ambient temperature, the corresponding phase loss preset coefficient can be directly determined by looking up the table. Alternatively, linear interpolation can be performed on the coefficients of adjacent intervals, and the final phase loss preset coefficient can be calculated proportionally. The relationship between load rate, ambient temperature, and phase loss preset coefficient can also be fitted using mathematical functions. Alternatively, an intelligent algorithm can be introduced, using a preset network model, inputting parameters such as load rate and ambient temperature, and directly outputting the phase loss preset coefficient. These are merely examples and are not intended to limit the method.

[0033] Step S104: Determine the current judgment threshold based on the phase loss preset coefficient, the number of current samplings within the preset time period, and the preset unit current value.

[0034] The preset unit current value in this embodiment of the invention can be 1A. The current judgment threshold can be determined based on the phase loss preset coefficient, the number of current samplings within a preset time period, and the preset unit current value. There is no limitation on how to determine the current judgment threshold. For example, the phase loss preset coefficient can be multiplied by the number of current samplings and the unit current value, i.e., K×CheckCount×1A, to obtain the current judgment threshold. This is just an example.

[0035] In this embodiment of the invention, the preset unit current value can be 1A. The current judgment threshold can be determined by the phase loss preset coefficient, the number of current acquisitions within the preset time period, and the preset unit current value, i.e., K×CheckCount×1A. The current judgment threshold can also be dynamically adjusted based on the real-time operating status of the motor. For example, if the three-phase current is stable at more than 120% of the current judgment threshold within the continuous phase loss detection period, the current judgment threshold can be increased to reduce sensitivity and avoid misjudgment. Alternatively, a fluctuation compensation term can be introduced, and the threshold can be set in combination with the current fluctuation characteristics. This is just an example.

[0036] Step S105: When the cumulative value of the current in any phase is less than the current judgment threshold, it is determined that the motor has a phase loss fault.

[0037] In this embodiment of the invention, when the accumulated value of any phase current is less than the current judgment threshold, a motor defect fault can be determined, and then the motor protection mechanism can be triggered, such as triggering protection mechanisms such as shutting down pulse width modulation (PWM) output, power-off, and alarm, which are only examples.

[0038] The motor phase loss detection method provided in this embodiment collects the three-phase current of the motor, as well as the current motor load rate and ambient temperature. It accumulates the absolute values ​​of the current of each phase collected within a preset time period to obtain the accumulated value of the current of each phase. Based on the current motor load rate and ambient temperature, a phase loss preset coefficient is determined. Based on the phase loss preset coefficient, the number of current acquisitions within the preset time period, and a preset unit current value, a current judgment threshold is determined. When the accumulated value of any phase current is less than the current judgment threshold, a motor phase loss fault is determined. By collecting and accumulating the three-phase current, combined with the coefficient threshold set for the real-time operating conditions of the motor, a rapid and accurate judgment of motor phase loss faults can be achieved, and the motor protection mechanism can be triggered in a timely manner to avoid damage to the motor caused by phase loss.

[0039] This embodiment provides a method for detecting a missing phase in a motor, which can be used in the controller of a motor device. Figure 2 This is a flowchart of a motor phase loss detection method according to an embodiment of the present invention, as shown below. Figure 2 As shown, the process includes the following steps: Step S201: Collect the three-phase current corresponding to the motor, and obtain the current motor load rate and ambient temperature.

[0040] Specifically, step S201 includes: Step S2011: Based on the pulse width modulation frequency of the external motor drive system, collect the corresponding three-phase current of the motor.

[0041] In this embodiment of the invention, the current sampling frequency can be consistent with the pulse width modulation frequency of the external drive system of the motor. By using the pulse width modulation frequency of the external drive system of the motor to collect the three-phase current corresponding to the motor, the sampling frequency and the pulse width modulation frequency are synchronized. The sampled current data can reflect the gradual change of the current in real time, perfectly capture the dynamic change of the current, and improve the current sampling accuracy.

[0042] Step S202: The absolute values ​​of the current collected for each phase within a preset time period are summed to obtain the accumulated value of the current for each phase. For details, please refer to [link to relevant documentation]. Figure 1 Step S102 of the illustrated embodiment will not be described again here.

[0043] Step S203: Determine the phase loss preset coefficient based on the current motor load rate and ambient temperature.

[0044] Specifically, step S203 includes: Step S2031: Determine the coefficient correction value based on the current motor load rate and ambient temperature.

[0045] Step S2032: Multiply the coefficient correction value by the basic phase loss coefficient to obtain the phase loss preset coefficient.

[0046] This invention does not limit the method for determining the coefficient correction value based on the current motor load rate and ambient temperature. For example, different motor operating conditions (including different motor load rates and ambient temperatures) can be preset, and multiple experiments can be conducted based on the motor characteristics to determine the coefficient correction value corresponding to different motor operating conditions. In practical applications, the corresponding coefficient correction value can be found based on the currently collected motor load rate and ambient temperature. Alternatively, the difference between the current motor load rate and the rated load rate can be multiplied by a preset load coefficient to obtain the load correction product. Then, the difference between the current ambient temperature and the standard ambient temperature can be multiplied by a preset temperature coefficient to obtain the temperature correction product. Finally, the load correction product and the temperature correction product are added together to obtain the coefficient correction value. This is only an example.

[0047] In this embodiment of the invention, a basic phase loss coefficient can be set, typically 0.8, to ensure that detection is triggered when the current drops to 80% of the rated value, leaving a 20% safety margin to avoid misjudgment due to normal fluctuations. This is just an example. The coefficient correction value can be multiplied by the basic phase loss coefficient to obtain the phase loss preset coefficient.

[0048] This invention correlates the coefficient correction value with the load rate and ambient temperature in real time, so that the phase loss preset coefficient is dynamically adjusted according to the motor operating conditions, thereby improving the adaptability and stability of phase loss protection under complex operating conditions.

[0049] Specifically, the controller determines the coefficient correction value based on the current motor load rate and ambient temperature, including: dividing the current motor load rate by the rated load rate to obtain the load deviation coefficient; multiplying the load deviation coefficient by a first preset coefficient to obtain a first correction value; subtracting the temperature standard value from the ambient temperature to obtain a temperature deviation value; dividing the temperature deviation value by the rated temperature difference value to obtain a temperature deviation coefficient; multiplying the temperature deviation coefficient by a second preset coefficient to obtain a second correction value; and determining the coefficient correction value based on the first correction value and the second correction value.

[0050] In this embodiment of the invention, the current motor load rate can be divided by the rated load rate to obtain a load deviation coefficient. The load deviation coefficient is then multiplied by a first preset coefficient to obtain a first correction value. The rated load rate is determined based on the attribute information of the currently detected motor, taking 100% as an example. The first preset coefficient is the weight of the load deviation on the correction value, which can be set based on the motor's load characteristics and the reliability requirements of the application scenario, taking 0.1 as an example. Simultaneously, the current ambient temperature can be subtracted from the temperature standard value to obtain a temperature deviation value. The temperature deviation value is then divided by the rated temperature difference value to obtain a temperature deviation coefficient. The temperature deviation coefficient is then divided by a second preset coefficient to obtain a second correction value. The temperature standard value can be the reference ambient temperature for normal motor operation, taking 25℃ as an example. The rated temperature difference value can be the maximum allowable ambient temperature deviation for the motor, taking 15℃ as an example. The second preset coefficient is the weight of the temperature deviation on the correction value, which can be comprehensively set based on the motor's travel information and the actual application scenario, taking 0.05 as an example. Finally, a coefficient correction value can be determined based on the first and second correction values, as provided in this example only.

[0051] This invention quantifies the effects of load rate and temperature by multiplying the deviation coefficient by the weight, thereby improving the accuracy of coefficient determination. Furthermore, by setting correction boundaries using the rated load rate and rated temperature difference, it ensures the stability of the coefficient correction value and avoids protection malfunctions caused by parameter mutations.

[0052] Specifically, the phase loss preset coefficient can be calculated using the following formula in the embodiments of the present invention:

[0053] in, Indicates the phase loss preset coefficient; Indicates the basic phase loss coefficient; Indicates the first preset coefficient; Indicates the current motor load rate; Indicates the rated load rate; Indicates the second preset coefficient; Indicates the current ambient temperature; Indicates the standard temperature value; This indicates the rated temperature difference value.

[0054] In this embodiment of the invention, the basic phase loss coefficient can be set to 0.8, with a safety margin of 0.2 to avoid misjudgment of normal fluctuations. The first preset coefficient can be the weight of the load rate deviation on the correction value, taking 0.1 as an example. The rated load rate can be determined based on the attribute information of the currently detected motor, taking 100% as an example. The second preset coefficient is the weight of the temperature deviation on the correction value, taking 0.05 as an example. The standard temperature value can be the reference ambient temperature for normal operation of the motor, taking 25℃ as an example. The rated temperature difference value can be the maximum allowable ambient temperature deviation of the motor, taking 15℃ as an example.

[0055] In a specific embodiment, when the current motor load rate is 90% and the ambient temperature is 40℃, K=0.8×(1-0.1×0.9)×(1+0.05×1)=0.8×0.91×1.05≈0.76. If Iaaccumulated / Ibaccumulated / Ibaccumulated<(0.76×10000×1A)=7600, then it is determined that the motor is missing a phase.

[0056] After collecting the current motor load rate and ambient temperature, this invention can directly calculate the phase loss preset coefficient based on the above formula, which can be used for subsequent motor phase loss detection. This is simple to implement and easy to put into practice, improving the efficiency of phase loss detection.

[0057] Step S204: Based on the phase loss preset coefficient, the number of current samplings within the preset time period, and the preset unit current value, determine the current judgment threshold. For details, please refer to [link to relevant documentation]. Figure 1 Step S104 of the illustrated embodiment will not be described again here.

[0058] Step S205: When the accumulated value of the current in any phase is less than the current judgment threshold, a phase loss fault in the motor is determined. For details, please refer to [link to relevant documentation]. Figure 1 Step S105 of the illustrated embodiment will not be described again here.

[0059] This embodiment provides a method for detecting a missing phase in a motor, which can be used in the controller of motor equipment. Figure 3 This is a flowchart of a motor phase loss detection method according to an embodiment of the present invention, as shown below. Figure 3 As shown, the process includes the following steps: Step S301: Collect the three-phase current corresponding to the motor, and obtain the current motor load rate and ambient temperature. For details, please refer to [link to relevant documentation]. Figure 2 Step S201 of the illustrated embodiment will not be described again here.

[0060] Step S302: The absolute values ​​of the current collected within the preset time period are summed to obtain the accumulated value of the current for each phase. For details, please refer to [link to relevant documentation]. Figure 2 Step S202 of the illustrated embodiment will not be described again here.

[0061] Step S303: Determine the phase loss preset coefficient based on the current motor load rate and ambient temperature.

[0062] In one alternative implementation, the controller determines a coefficient correction value based on the current motor load rate and ambient temperature, and multiplies the coefficient correction value by the basic phase loss coefficient to obtain the phase loss preset coefficient.

[0063] Specifically, the basic phase loss coefficient can be obtained through the following steps: select the maximum accumulated value among the three-phase current accumulated values; divide the maximum accumulated value by the number of current samplings within a preset time period to obtain the first coefficient value; add the first coefficient value to the preset basic coefficient to obtain the basic phase loss coefficient.

[0064] In addition to being obtained by pre-setting the phase loss coefficient value, the basic phase loss coefficient of this invention can also be obtained by detecting a phase loss in the motor, calculating the cumulative value of the current of each phase within a preset time period, and selecting the maximum cumulative value among the cumulative values ​​of the three-phase current. Then, the maximum accumulated value can be divided by the product of the number of current samplings within the preset time period and the preset unit current to obtain the first coefficient value. The first coefficient value can then be added to the preset base coefficient to obtain the base phase loss coefficient, as shown in the following formula:

[0065] in, Indicates the maximum accumulated value; This indicates the preset unit current, for example, 1mA; the preset base coefficient can be set according to the motor characteristics and actual application scenarios, for example, 0.2.

[0066] This invention indirectly uses the current current level of the normal phase as a reference by introducing the cumulative value of the maximum three-phase current, so that the basic phase loss coefficient and the actual three-phase current value can be dynamically set, thereby improving the accuracy and adaptability of defect detection.

[0067] Step S304: When the current motor load rate is detected to be greater than the first preset load rate threshold, and / or when the ambient temperature is detected to be less than the first preset temperature threshold, the phase loss preset coefficient is reduced; or, when the current motor load rate is detected to be less than the second preset load rate threshold, and / or when the ambient temperature is detected to be greater than the second preset temperature threshold, the phase loss preset coefficient is increased.

[0068] In this embodiment of the invention, when the current motor load rate is detected to be greater than a first preset load rate threshold, the calculated phase loss preset coefficient can be reduced. The first preset load rate threshold can be set according to motor characteristics and actual application scenarios, taking 90% as an example. The method for reducing the calculated phase loss preset coefficient is not limited; it can be adjusted by setting an adjustment step size. For example, if the calculated load rate difference is 2, the corresponding adjustment step size is 0.05. Then, the difference between the current motor load rate and 90% can be calculated to determine the target adjustment step size, and the phase loss preset coefficient can be reduced based on the target adjustment step size. Alternatively, the calculated phase loss preset coefficient can be multiplied by a first adjustment coefficient to obtain the reduced phase loss preset coefficient. The first adjustment coefficient should be less than 1, taking 0.91 as an example. Multiplying the calculated phase loss preset coefficient by 0.91 yields the reduced phase loss preset coefficient. This is merely an example.

[0069] In this embodiment of the invention, when the current motor load rate is detected to be low, such as less than the second preset load rate threshold (e.g., 30%), the calculated phase loss preset coefficient can be increased. The method of increasing the phase loss preset coefficient is not limited. It can be calculated by adjusting the step size or by multiplying by the second adjustment coefficient. The second adjustment coefficient should not be less than 1. For example, 1.05 is used. The calculated phase loss preset coefficient is multiplied by 1.05 to obtain the increased phase loss preset coefficient.

[0070] In this embodiment of the invention, when the current ambient temperature is detected to be lower than the first preset temperature threshold, the phase loss preset coefficient can be reduced. The method of reducing the phase loss preset coefficient will not be described in detail here. Taking 20°C as an example, the first preset temperature threshold is used. When the current ambient temperature is detected to be higher than the second preset temperature threshold, the phase loss preset coefficient can be increased. The method of increasing the phase loss preset coefficient will not be described in detail here. Taking 40°C as an example, the second preset temperature threshold is used.

[0071] This invention triggers the dynamic adjustment of the phase loss preset coefficient by using two-dimensional conditions of load rate and ambient temperature, avoiding the problems of over-protection or under-protection caused by fixed coefficients. It can prevent the extreme of phase loss protection and ensure the operational stability under different working conditions.

[0072] Step S305: Based on the phase loss preset coefficient, the number of current samplings within a preset time period, and the preset unit current value, determine the current judgment threshold. For details, please refer to [link to relevant documentation]. Figure 2 Step S204 of the illustrated embodiment will not be described again here.

[0073] Step S306: If the accumulated current value of any phase is less than the current judgment threshold, a phase loss fault in the motor is determined. For details, please refer to [link to relevant documentation]. Figure 2 Step S205 of the illustrated embodiment will not be described again here.

[0074] In specific embodiments, such as Figure 4 As shown, in this embodiment of the invention, the three-phase current corresponding to the motor is collected at a fixed sampling frequency, and the current of each phase collected within a preset time period is accumulated to obtain the accumulated value of the current of each phase. Then, the accumulated value of the current of each phase is used to determine the phase loss. If the phase loss condition is met, the protection mechanism (such as shutdown) is triggered. If the phase loss condition is not met, the phase loss detection is repeated. For detailed description, please refer to the above embodiment, which will not be repeated here.

[0075] This embodiment also provides a motor device, such as... Figure 5 As shown, the motor device includes a motor 51 and a controller 52. The controller includes a memory and a processor. The memory and the processor are interconnected. The memory stores computer instructions. The processor executes the computer instructions to perform the motor phase loss detection method.

[0076] This embodiment also provides a motor phase loss detection device, which is used to implement the above embodiments and preferred embodiments; details already described will not be repeated. As used below, the term "module" can refer to a combination of software and / or hardware that performs a predetermined function. Although the device described in the following embodiments is preferably implemented in software, hardware implementation, or a combination of software and hardware, is also possible and contemplated.

[0077] This embodiment provides a motor phase loss detection device, such as... Figure 6 As shown, the system includes: a data acquisition module 601, used to acquire the three-phase current corresponding to the motor, and to obtain the current motor load rate and ambient temperature; a current accumulation module 602, used to accumulate the absolute values ​​of the current of each phase acquired within a preset time period to obtain the accumulated value of the current of each phase; a coefficient determination module 603, used to determine the phase loss preset coefficient based on the current motor load rate and ambient temperature; a current threshold calculation module 604, used to determine the current judgment threshold based on the phase loss preset coefficient, the number of current acquisitions within a preset time period, and a preset unit current value; and a motor fault determination module 605, used to determine that the motor has a phase loss fault when the accumulated value of any phase current is less than the current judgment threshold.

[0078] In some optional implementations, the coefficient determination module 603 includes: a correction value calculation unit, used to determine a coefficient correction value based on the current motor load rate and ambient temperature; and a coefficient processing unit, used to multiply the coefficient correction value by the basic phase loss coefficient to obtain the phase loss preset coefficient.

[0079] In some optional implementations, the correction value calculation unit includes: a load deviation calculation subunit, used to divide the current motor load rate by the rated load rate to obtain a load deviation coefficient; a first correction calculation subunit, used to multiply the load deviation coefficient by a first preset coefficient to obtain a first correction value; a temperature deviation calculation subunit, used to subtract a temperature standard value from the ambient temperature to obtain a temperature deviation value; a temperature deviation coefficient calculation subunit, used to divide the temperature deviation value by the rated temperature difference value to obtain a temperature deviation coefficient; a second correction calculation subunit, used to multiply the temperature deviation coefficient by a second preset coefficient to obtain a second correction value; and a coefficient correction value calculation subunit, used to determine a coefficient correction value based on the first correction value and the second correction value.

[0080] In some optional implementations, the phase loss preset coefficient is calculated using the following formula:

[0081] in, Indicates the phase loss preset coefficient; Indicates the basic phase loss coefficient; Indicates the first preset coefficient; Indicates the current motor load rate; Indicates the rated load rate; Indicates the second preset coefficient; Indicates the current ambient temperature; Indicates the standard temperature value; This indicates the rated temperature difference value.

[0082] In one optional implementation, the basic phase loss coefficient is obtained by the following steps: selecting the maximum accumulated value among the three-phase current accumulated values; dividing the maximum accumulated value by the product of the number of current samplings within a preset time period and a preset unit current to obtain a first coefficient value; and adding the first coefficient value to a preset basic coefficient to obtain the basic phase loss coefficient.

[0083] In one optional implementation, before determining the current judgment threshold based on the phase loss preset coefficient, the number of current samplings within a preset time period, and the preset unit current value, the motor phase loss detection device further includes: a coefficient reduction module, used to reduce the phase loss preset coefficient when the current motor load rate is detected to be greater than a first preset load rate threshold, and / or when the ambient temperature is detected to be less than a first preset temperature threshold; or, a coefficient increase module, used to increase the phase loss preset coefficient when the current motor load rate is detected to be less than a second preset load rate threshold, and / or when the ambient temperature is detected to be greater than a second preset temperature threshold.

[0084] In one optional implementation, the data acquisition module 601 includes a current acquisition unit for acquiring the three-phase current corresponding to the motor based on the pulse width modulation frequency of the external motor drive system.

[0085] Further functional descriptions of the above modules and units are the same as those in the corresponding embodiments described above, and will not be repeated here.

[0086] In this embodiment, the motor phase loss detection device is presented in the form of a functional unit. Here, a unit refers to an ASIC (Application Specific Integrated Circuit) circuit, a processor and memory that execute one or more software or fixed programs, and / or other devices that can provide the above functions.

[0087] This invention also provides a controller having the above-described features. Figure 6 The motor phase loss detection device shown is shown.

[0088] Please see Figure 7 , Figure 7 This is a schematic diagram of the structure of a controller in a motor device provided by an optional embodiment of the present invention, such as... Figure 7As shown, the controller includes one or more processors 10, memory 20, and interfaces for connecting the components, including high-speed interfaces and low-speed interfaces. The components communicate with each other via different buses and can be mounted on a common motherboard or otherwise as required. The processors can process instructions executed within the controller, including instructions stored in or on memory to display graphical information of a GUI on external input / output devices (such as display devices coupled to the interfaces). In some alternative implementations, multiple processors and / or multiple buses can be used with multiple memories and multiple memory modules, if desired. Similarly, multiple controllers can be connected, each providing some of the necessary operations (e.g., as a server array, a group of blade servers, or a multiprocessor system). Figure 7 Take a processor 10 as an example.

[0089] Processor 10 may be a central processing unit, a network processor, or a combination thereof. Processor 10 may further include a hardware chip. The hardware chip may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GDA), or any combination thereof.

[0090] The memory 20 stores instructions executable by at least one processor 10 to cause at least one processor 10 to perform the method shown in the above embodiments.

[0091] The memory 20 may include a program storage area and a data storage area. The program storage area may store the operating system and applications required for at least one function; the data storage area may store data created based on the use of the controller. Furthermore, the memory 20 may include high-speed random access memory and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some alternative embodiments, the memory 20 may optionally include memory remotely located relative to the processor 10, and these remote memories may be connected to the controller via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0092] The memory 20 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk or solid-state drive; the memory 20 may also include a combination of the above types of memory.

[0093] The controller also includes an input device 30 and an output device 40. The processor 10, memory 20, input device 30, and output device 40 can be connected via a bus or other means. Figure 7Taking the example of a connection between China and Israel via a bus.

[0094] Input device 30 can receive input numerical or character information, and generate key signal inputs related to user settings and function control of the controller, such as a touch screen, keypad, mouse, trackpad, touchpad, joystick, one or more mouse buttons, trackball, joystick, etc. Output device 40 may include display devices, auxiliary lighting devices (e.g., LEDs), and haptic feedback devices (e.g., vibration motors). The aforementioned display devices include, but are not limited to, liquid crystal displays, light-emitting diodes, displays, and plasma displays. In some alternative embodiments, the display device may be a touch screen.

[0095] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code, which, when accessed and executed by the computer, processor, or hardware, implements the methods shown in the above embodiments.

[0096] A portion of this invention can be applied as a computer program product, such as computer program instructions, which, when executed by a computer, can invoke or provide the methods and / or technical solutions according to the invention through the operation of the computer. Those skilled in the art will understand that the forms in which computer program instructions exist in a computer-readable medium include, but are not limited to, source files, executable files, installation package files, etc. Correspondingly, the ways in which computer program instructions are executed by a computer include, but are not limited to: the computer directly executing the instructions, or the computer compiling the instructions and then executing the corresponding compiled program, or the computer reading and executing the instructions, or the computer reading and installing the instructions and then executing the corresponding installed program. Here, the computer-readable medium can be any available computer-readable storage medium or communication medium accessible to a computer.

[0097] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A method for detecting phase loss in a motor, characterized in that, The method includes: Collect the three-phase current corresponding to the motor, as well as obtain the current motor load rate and ambient temperature; The absolute values ​​of the current in each phase collected within a preset time period are summed to obtain the accumulated value of the current in each phase. Based on the current motor load rate and ambient temperature, determine the phase loss preset coefficient; Based on the phase loss preset coefficient, the number of current samplings within the preset time period, and the preset unit current value, the current judgment threshold is determined. If the cumulative value of the current in any phase is less than the current judgment threshold, the motor is determined to have a phase loss fault.

2. The method according to claim 1, characterized in that, The determination of the phase loss preset coefficient based on the current motor load rate and ambient temperature includes: Based on the current motor load rate and ambient temperature, determine the coefficient correction value; Multiply the coefficient correction value by the basic phase loss coefficient to obtain the phase loss preset coefficient.

3. The method according to claim 2, characterized in that, The determination of the coefficient correction value based on the current motor load rate and ambient temperature includes: Divide the current motor load rate by the rated load rate to obtain the load deviation coefficient; Multiply the load deviation coefficient by a first preset coefficient to obtain a first correction value; Subtract the standard temperature value from the ambient temperature to obtain the temperature deviation value; Divide the temperature deviation value by the rated temperature difference value to obtain the temperature deviation coefficient; Multiply the temperature deviation coefficient by the second preset coefficient to obtain the second correction value; Based on the first correction value and the second correction value, the coefficient correction value is determined.

4. The method according to claim 2 or 3, characterized in that, The phase loss preset coefficient is calculated using the following formula: in, Indicates the phase loss preset coefficient; Indicates the basic phase loss coefficient; Indicates the first preset coefficient; Indicates the current motor load rate; Indicates the rated load rate; Indicates the second preset coefficient; Indicates the current ambient temperature; Indicates the standard temperature value; This indicates the rated temperature difference value.

5. The method according to claim 2, characterized in that, The basic phase loss coefficient is obtained through the following steps: Select the maximum accumulated value among the three-phase current accumulated values; The first coefficient value is obtained by dividing the maximum accumulated value by the product of the number of current samplings within the preset time period and the preset unit current. The first coefficient value is added to the preset basic coefficient to obtain the basic phase loss coefficient.

6. The method according to claim 2, characterized in that, Before determining the current judgment threshold based on the phase loss preset coefficient, the number of current samplings within the preset time period, and the preset unit current value, the method further includes: When the current motor load rate is detected to be greater than a first preset load rate threshold, and / or when the ambient temperature is detected to be less than a first preset temperature threshold, the phase loss preset coefficient is reduced; or, When the current motor load rate is detected to be less than the second preset load rate threshold, and / or when the ambient temperature is detected to be greater than the second preset temperature threshold, the phase loss preset coefficient is increased.

7. The method according to claim 1, characterized in that, The three-phase current corresponding to the motor being collected includes: Based on the pulse width modulation frequency of the external motor drive system, the three-phase current of the motor is collected.

8. A motor phase loss detection device, characterized in that, The device includes: The data acquisition module is used to collect the three-phase current corresponding to the motor, as well as to obtain the current motor load rate and ambient temperature; The current accumulation module is used to accumulate the absolute values ​​of the current of each phase collected within a preset time period to obtain the accumulated value of the current of each phase. The coefficient determination module is used to determine the phase loss preset coefficient based on the current motor load rate and ambient temperature; The current threshold calculation module is used to determine the current judgment threshold based on the phase loss preset coefficient, the number of current acquisitions within the preset time period, and the preset unit current value. The motor fault determination module is used to determine a motor phase loss fault when the cumulative value of the current in any phase is less than the current judgment threshold.

9. A motor device, characterized in that, The motor device includes a motor and a controller. The controller includes a memory and a processor. The memory and the processor are communicatively connected to each other. The memory stores computer instructions. The processor executes the computer instructions to perform the motor phase loss detection method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing the computer to execute the motor phase loss detection method according to any one of claims 1 to 7.

Images