Controller, robot, three-phase motor open-phase detection method, and storage medium

Abstract

This invention discloses a controller, a robot, a three-phase motor phase loss detection method, and a storage medium. It acquires the first and second stator currents of the three-phase motor in real time, and constructs a stationary coordinate system based on these currents. The first stator current is decomposed into a first horizontal axis component current and a first vertical axis component current in the stationary coordinate system. The second stator current is also decomposed into a second horizontal axis component current and a second vertical axis component current. The horizontal and vertical axis currents are acquired from the stationary coordinate system. Based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current, the phase loss detection result is determined. This invention improves the accuracy, efficiency, and comprehensiveness of three-phase motor phase loss detection, and reduces the cost of three-phase motor phase loss detection.

Description

Technical Field

[0001] This invention relates to the field of three-phase motor testing, and more particularly to a controller, a robot, a method for detecting phase loss in a three-phase motor, and a storage medium. Background Technology

[0002] Currently, three-phase motors are typically driven by controlling a three-phase bridge inverter circuit. However, due to environmental corrosion or vibration, prolonged use can lead to poor contact between the three-phase bridge inverter circuit and the three-phase motor, or even internal disconnection within the motor, resulting in a phase loss. Prolonged operation with a phase loss can cause abnormal noise, overheating, and potentially burn out the stator windings, or even damage the three-phase bridge inverter circuit. Therefore, phase loss detection for three-phase motors is crucial.

[0003] In existing technologies, the hardware circuit method for phase loss detection requires adding additional hardware processing circuits to the three-phase bridge inverter circuit, resulting in high detection costs. While the software algorithm method for phase loss detection integrates the three-phase current of the three-phase motor over a period of time, determining phase loss when the integral is zero, it ignores the fact that in actual use, only two-phase currents are often collected. Therefore, determining whether a phase is missing by collecting complete three-phase currents may not be feasible or may require additional hardware processing circuits. Furthermore, the software algorithm in existing technologies has detection errors; the detected integral value may not be zero when a phase is missing, resulting in low detection accuracy. Summary of the Invention

[0004] This invention provides a controller, a robot, a method for detecting phase loss in a three-phase motor, and a storage medium to solve the aforementioned problems in the prior art.

[0005] A controller connected to a three-phase motor includes a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor. When the processor executes the computer-readable instructions, it performs the following steps:

[0006] The first stator current and the second stator current of the three-phase motor are acquired in real time. The first stator current refers to any one of the three-phase stator currents, and the second stator current refers to any one of the three-phase stator currents that is different from the first stator current.

[0007] A stationary coordinate system for the motor is constructed based on the first stator current and the second stator current. The first stator current is decomposed in the stationary coordinate system into a first horizontal axis component current located on the horizontal axis and a first vertical axis component current located on the vertical axis. The second stator current is decomposed in the stationary coordinate system into a second horizontal axis component current located on the horizontal axis and a second vertical axis component current located on the vertical axis.

[0008] The horizontal axis current and the vertical axis current are obtained from the stationary coordinate system of the motor; the horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current.

[0009] The phase loss detection result is determined based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current.

[0010] A robot including the aforementioned controller.

[0011] A method for detecting phase loss in a three-phase motor, comprising:

[0012] The first stator current and the second stator current of the three-phase motor are acquired in real time. The first stator current refers to any one of the three-phase stator currents, and the second stator current refers to any one of the three-phase stator currents that is different from the first stator current.

[0013] A stationary coordinate system for the motor is constructed based on the first stator current and the second stator current. The first stator current is decomposed in the stationary coordinate system into a first horizontal axis component current located on the horizontal axis and a first vertical axis component current located on the vertical axis. The second stator current is decomposed in the stationary coordinate system into a second horizontal axis component current located on the horizontal axis and a second vertical axis component current located on the vertical axis.

[0014] The horizontal axis current and the vertical axis current are obtained from the stationary coordinate system of the motor; the horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current.

[0015] The phase loss detection result is determined based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current.

[0016] A computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described three-phase motor phase loss detection method.

[0017] The aforementioned controller, robot, three-phase motor phase loss detection method, and storage medium only need to detect the stator current (such as the first stator current and the second stator current) of two stator windings in the three-phase motor, and determine the intermediate variables corresponding to the above two stator currents, namely the horizontal axis current and the vertical axis current, to realize the phase loss detection of the three-phase motor, thereby quickly and accurately determining whether there is a phase loss in the three-phase stator windings of the three-phase motor. This invention improves the accuracy, efficiency, and comprehensiveness of three-phase motor phase loss detection; moreover, this invention does not require additional hardware processing circuitry, reducing the cost of three-phase motor phase loss detection. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below 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 effort.

[0019] Figure 1 This is a schematic diagram of a controller in one embodiment of the present invention;

[0020] Figure 2 This is a flowchart of a three-phase motor phase loss detection method according to an embodiment of the present invention;

[0021] Figure 3 This is a schematic diagram of a three-phase inverter bridge and its driving circuit in one embodiment of the present invention;

[0022] Figure 4 This is a schematic diagram of the stationary coordinate system of the motor in one embodiment of the present invention. Detailed Implementation

[0023] 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, not all, of the embodiments of the present invention. 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.

[0024] In one embodiment, a controller is provided, the internal structure of which can be as follows: Figure 1As shown, the controller includes a processor, memory, network interface, and database connected via a system bus. The processor provides computational and control capabilities. The memory includes a readable storage medium and internal memory. The readable storage medium stores an operating system, computer-readable instructions, and a database. The internal memory provides an environment for the operation of the operating system and computer-readable instructions in the readable storage medium. The database stores data used by the corresponding robot navigation path width setting method. The network interface communicates with external terminals via a network connection. When the computer-readable instructions are executed by the processor, they implement a three-phase motor phase loss detection method. The readable storage medium provided in this embodiment includes both non-volatile and volatile readable storage media. Preferably, the controller may further include an input device and a display screen. The input device receives signals, text, etc., sent by other devices; the display screen can display phase loss detection results, etc.

[0025] In one embodiment, a controller is provided, the controller being connected to a three-phase motor, the three-phase motor including a first-phase stator winding, a second-phase stator winding, and a third-phase stator winding; as shown Figure 1 As shown, the controller includes a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor, such as... Figure 2 When the processor described herein executes the computer-readable instructions, it performs the following steps:

[0026] S10: Real-time acquisition of the first stator current of the first phase stator winding and the second stator current of the second phase stator winding;

[0027] Furthermore, such as Figure 3 As shown, Figure 3The diagram illustrates a three-phase inverter bridge and its drive circuit in a three-phase motor. The three-phase inverter bridge and its drive circuit include six transistors: transistors Q1, Q2, and Q3 are connected to the positive terminal of the DC power supply; transistors Q4, Q5, and Q6 are connected to the negative terminal of the DC power supply. Furthermore, the switching on or off of transistors Q3 and Q6 determines whether the first phase stator winding c is missing a phase; the switching on or off of transistors Q2 and Q5 determines whether the second phase stator winding b is missing a phase; and the switching on or off of transistors Q1 and Q4 determines whether the third phase stator winding a is missing a phase. For example, assuming a phase loss occurs in the third phase stator winding a, but no phase loss occurs in the first phase stator winding or the second phase stator winding, then the first transistor and the fourth transistor are disconnected, either the second transistor or the fifth transistor is turned on, and either the third transistor or the sixth transistor is turned on. For example, when the second transistor and the third transistor are turned on, and the fifth transistor and the sixth transistor are disconnected; when the second transistor and the sixth transistor are turned on, and the third transistor and the fifth transistor are disconnected; when the fifth transistor and the third transistor are turned on, and the second transistor and the sixth transistor are disconnected; when the fifth transistor and the sixth transistor are turned on, and the second transistor and the third transistor are disconnected.

[0028] Understandably, the three-phase motor can be a three-phase synchronous motor or a three-phase asynchronous motor installed on the robot. This three-phase motor includes a first-phase stator winding, a second-phase stator winding, and a third-phase stator winding. The first-phase stator winding corresponds to the first stator current, the second-phase stator winding corresponds to the second stator current, and the third-phase stator winding corresponds to the third stator current. The frequencies and potential amplitudes of the first, second, and third stator currents are equal, and the phase difference between the first, second, and third stator currents is 120°. Furthermore, the first, second, and third stator currents of the three-phase motor can be acquired in real time through a current sampling module.

[0029] S20: Construct a stationary coordinate system for the motor based on the first stator current and the second stator current; the first stator current is decomposed in the stationary coordinate system into a first horizontal axis component current located on the horizontal axis and a first vertical axis component current located on the vertical axis; the second stator current is decomposed in the stationary coordinate system into a second horizontal axis component current located on the horizontal axis and a second vertical axis component current located on the vertical axis.

[0030] Understandably, since the first stator current, the second stator current, and the third stator current are all vector currents, that is, the first stator current, the second stator current, and the third stator current are determined by the current value and the phase, the first stator current can be vector decomposed into the first horizontal axis component current located on the horizontal axis and the first vertical axis component current located on the vertical axis; the second stator current can be vector decomposed into the second horizontal axis component current located on the horizontal axis and the second vertical axis component current located on the vertical axis.

[0031] S30: Obtain the horizontal axis current and the vertical axis current from the stationary coordinate system of the motor; the horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current.

[0032] Understandably, the horizontal axis current and the vertical axis current are generated by transforming the first stator current and the second stator current using the Clark algorithm; furthermore, the horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the current value of the horizontal axis current is equal to the absolute value of the sum of the first horizontal axis component current and the second horizontal axis component current; the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current, and the current value of the vertical axis current is equal to the absolute value of the sum of the first vertical axis component current and the second vertical axis component current.

[0033] S40: Determine the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current.

[0034] Understandably, the phase loss detection results include no phase loss in the three-phase motor, phase loss in any one phase of the stator winding of the three-phase motor, and phase loss in all stator windings of the three-phase motor.

[0035] Specifically, after obtaining the horizontal and vertical axis currents in the stationary coordinate system of the motor, the phase loss detection results of the three-phase motor are determined based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current, so as to determine whether to start the three-phase motor.

[0036] In this embodiment, by detecting the stator current of two phase stator windings in a three-phase motor (such as the first stator current and the second stator current), and using intermediate variables corresponding to the stator current, namely the horizontal axis current and the vertical axis current, the three-phase motor is used to detect phase loss. This allows for rapid determination of whether a phase loss exists in the three-phase motor, and different phase loss conditions in the three-phase motor can be detected (such as a phase loss in one stator winding or a phase loss in all stator windings). This improves the accuracy, efficiency, and comprehensiveness of phase loss detection in three-phase motors. Furthermore, this invention does not require additional hardware processing circuitry, reducing the cost of phase loss detection in three-phase motors.

[0037] In one embodiment, step S20 includes:

[0038] Establish an initial rectangular coordinate system;

[0039] The first stator current and the second stator current are generated in the initial rectangular coordinate system; the angle between the first stator current and the positive vertical axis in the initial rectangular coordinate system is a preset line segment angle; the angle between the first stator current and the second stator current is 120 degrees.

[0040] Understandably, such as Figure 4 As shown, the initial rectangular coordinate system contains four quadrants. Therefore, in this embodiment, the first stator current is generated in the initial rectangular coordinate system (exemplarily, the first stator current can be...). Figure 4 The middle ib segment) and the second stator current (exemplarily, the second stator current can be Figure 4 (The ic line segment in the initial rectangular coordinate system). Further, the first stator current extends from the origin in the initial rectangular coordinate system toward the second quadrant, and the angle between the first stator current and the positive vertical axis in the initial rectangular coordinate system is a preset line segment angle (for example, the preset line segment angle can be set to 30 degrees, 45 degrees, etc.), that is, the first stator current is set in the second quadrant of the initial rectangular coordinate system;

[0041] Furthermore, the second stator current extends from the origin in the initial rectangular coordinate system towards the third quadrant, meaning the second stator current is positioned in the third quadrant of the initial rectangular coordinate system. The angle between the first stator current and the second stator current is 120° (i.e., the phase difference between the first stator current and the second stator current is 120°). Therefore, after determining the preset line segment angle, the angle between the first stator current and the horizontal or vertical axis of the initial rectangular coordinate system can be determined based on the constraint that the angle between the first stator current and the second stator current is 120°. For example, assuming the preset line segment angle is 30 degrees, the angle between the first stator current and the negative vertical axis of the initial rectangular coordinate system is 30 degrees.

[0042] Furthermore, Figure 4 In the embodiment shown, setting the first stator current in the second quadrant and the second stator current in the third quadrant is merely an example. In this invention, the first stator current and the second stator current can be set in any quadrant of the initial rectangular coordinate system, or the first stator current can be set to coincide with the horizontal or vertical axis of the initial rectangular coordinate system, as long as the angle between the first stator current and the second stator current is 120°.

[0043] In the initial rectangular coordinate system, a horizontal axis current coinciding with the positive horizontal axis is generated. The current value of the horizontal axis current is equal to the absolute value of the sum of the predicted horizontal axis component current, the first horizontal axis component current, and the second horizontal axis component current. The predicted horizontal axis component current refers to the component current of the predicted stator current on the horizontal axis. The predicted stator current is determined based on the first stator current and the second stator current. The direction of the horizontal axis current is positive.

[0044] In the initial rectangular coordinate system, a vertical axis current is generated that coincides with the positive vertical axis. The current value of the vertical axis current is equal to the absolute value of the sum of the predicted vertical axis component current, the first vertical axis component current, and the second vertical axis component current. The predicted vertical axis component refers to the component current of the predicted stator current on the vertical axis. The direction of the vertical axis current is positive.

[0045] Understandably, the horizontal axis current and vertical axis current can be obtained by applying the Clarke transform algorithm to the first stator current and the second stator current. The current value of the horizontal axis current is equal to the absolute value of the sum of the predicted stator current, the first horizontal axis component current, and the second horizontal axis component current. The predicted stator current is determined based on the first stator current and the second stator current. Understandably, in this embodiment, only the first stator current and the second stator current are collected. Since the vector sum of the first stator current, the second stator current, and the third stator current in the three-phase motor is 0, the third stator current can be predicted based on the relationship between the stator currents mentioned above, using the first stator current and the second stator current. That is, the obtained predicted stator current is the negative of the sum of the first stator current and the second stator current.

[0046] Understandably, assuming the first stator current is located in the second quadrant and the second stator current is located in the third quadrant, and the phase difference between the first, second, and third stator currents is 120°, then after determining the preset line segment angle, the specific positions of the first stator current in the second quadrant, the second stator current in the third quadrant, and the third stator current in the initial Cartesian coordinate system can be determined. For example, assuming the preset line segment angle is 30 degrees, after the Clarke transform algorithm, the predicted stator current (i.e., the predicted value of the third stator current) should be set to coincide with the positive horizontal axis in the initial Cartesian coordinate system (e.g., ...). Figure 4 (the ia line segment in the diagram).

[0047] Furthermore, after determining the preset line segment angle, the first horizontal axis component current decomposed into the horizontal axis of the initial rectangular coordinate system and the first vertical axis component current decomposed into the vertical axis of the initial rectangular coordinate system can be determined based on the preset line segment angle. Furthermore, the angle between the second stator current and the vertical axis of the initial rectangular coordinate system can be determined based on the preset line segment angle to determine the second horizontal axis component current and the second vertical axis component current. Simultaneously, the angle between the third stator current and the vertical axis of the initial rectangular coordinate system can be determined based on the preset line segment angle to determine the predicted stator current decomposed into the predicted horizontal axis component current located on the horizontal axis of the initial rectangular coordinate system and the predicted vertical axis component current located on the vertical axis of the initial rectangular coordinate system.

[0048] For example, assuming the first stator current is set in the second quadrant and the second stator current is set in the third quadrant, and the preset line segment angle is 30 degrees, the first and second horizontal axis component currents obtained by vector decomposition are both decomposed onto the negative horizontal axis in the initial rectangular coordinate system. The predicted stator current is set to coincide with the positive horizontal axis, therefore the predicted horizontal axis component current is equal to the predicted stator current, while the horizontal axis current (such as...) Figure 4 i in α The line segment is set to coincide with the positive horizontal axis of the initial rectangular coordinate system, meaning the direction of the horizontal axis current is opposite to the directions of the first and second horizontal axis component currents, and the same as the direction of the predicted stator current (positive). Therefore, the value of the horizontal axis current is the absolute value of the sum of the predicted stator current, the first horizontal axis component current, and the second horizontal axis component current, such as... Figure 4 The diagram shows a stationary coordinate system for the motor, assuming the first stator current is i. b The second stator current is i c The predicted stator current is ia, and the relationship between the first stator current, the second stator current, and the predicted stator current is: i a +i b +i c =0, therefore the predicted stator current is: i a =-(i b +i c ), and the first horizontal axis component current is The second horizontal axis component current is (The coefficient 1 / 2 is due to the sin30° decomposition conversion coefficient when the first stator current is decomposed into the first horizontal axis component current and the second stator current is decomposed into the second horizontal axis component current.) Furthermore, the Clarke transform algorithm in this embodiment is based on an algorithm with equal current amplitude. Therefore, in this embodiment, there is a transformation coefficient when performing the Clarke transform (in this embodiment, this transformation coefficient is set to 2 / 3). Thus, the horizontal axis current obtained after performing the Clarke transform on the predicted stator current, the first horizontal axis component current, and the second horizontal axis component current is: Therefore, the final result is the horizontal axis current i. α =-i b -i c ;

[0049] For example, assuming the first stator current is set in the second quadrant and the second stator current is set in the third quadrant, and the preset line segment angle is 30 degrees, the first vertical axis component current obtained by vector decomposition is decomposed onto the positive vertical axis in the initial rectangular coordinate system, and the second vertical axis component current is decomposed onto the negative vertical axis in the initial rectangular coordinate system. The predicted stator current is set to coincide with the positive horizontal axis, so the predicted stator current decomposed onto the vertical axis is 0, while the vertical axis current (such as...) Figure 4 i in b The line segment is set to coincide with the positive vertical axis of the initial rectangular coordinate system, meaning the direction of the vertical axis current is the same as the direction of the first vertical axis component current and opposite to the direction of the second vertical axis component current, which is positive. Therefore, the value of the vertical axis current is the absolute value of the sum of the first and second vertical axis component currents, and is unrelated to the predicted stator current. Figure 4 In the stationary coordinate system of the motor shown, if the first stator current is i b The second stator current is i c When the preset line segment angle is 30 degrees, the corresponding first vertical axis component current is: The corresponding second vertical axis component current is: (wherein, in this expression) The coefficient is due to the 120° phase difference between each phase of the stator current. When decomposing the first stator current and the second stator current to obtain the longitudinal current, there exists a decomposition conversion coefficient of sin120°. Therefore, the longitudinal current obtained after performing a Clarke transform on the predicted stator current, the first longitudinal component current, and the second longitudinal component current is... The corresponding vertical axis current is

[0050] The initial rectangular coordinate system containing the horizontal axis current and the vertical axis current is recorded as the motor stationary coordinate system.

[0051] Specifically, after generating a horizontal axis current that coincides with the positive horizontal axis in the initial rectangular coordinate system, and generating a vertical axis current that coincides with the positive vertical axis in the initial rectangular coordinate system, the initial rectangular coordinate system containing the horizontal axis current and the vertical axis current is recorded as the motor stationary coordinate system.

[0052] In one embodiment, step S40 includes:

[0053] After determining that both the first stator current and the second stator current are not zero, determine whether the current value of the horizontal axis current is zero;

[0054] Understandably, after obtaining the first stator current and the second stator current, it can be determined whether the current values ​​of the first stator current and the second stator current are zero. If both the first stator current and the second stator current are not zero, it indicates that the first phase stator winding corresponding to the first stator current in the current three-phase motor has not experienced a phase loss, and the second phase stator winding corresponding to the second stator current has also not experienced a phase loss. Furthermore, by determining whether the current value of the horizontal axis current is zero, it can be further determined whether a phase loss has occurred in the stator winding of the three-phase motor.

[0055] Furthermore, assume the first stator current is i b The second stator current is i c When, the corresponding horizontal axis current is i α =-i b -i c If the horizontal axis current is zero, it indicates that the value of the first stator current is equal to the value of the second stator current, and the direction of the first stator current is opposite to the direction of the second stator current, i.e., i b =-i c In a three-phase motor, the vector sum of the first stator current, the second stator current, and the third stator current is zero. Assume the third stator current is i. a That is, i a +i b +i c =0, therefore in i b =-i c Then, the third stator current i can be determined. a A value of zero indicates a phase loss in the third phase stator winding.

[0056] If the current value of the horizontal axis current is zero, then the first duration of recording begins; the first duration of recording refers to the duration during which the current value of the horizontal axis current remains zero from the first time point when the current value of the horizontal axis current is zero.

[0057] Understandably, when the horizontal axis current is zero, it could be due to a phase loss in the third phase stator winding of a three-phase motor, or it could occur instantaneously during normal operation of the three-phase motor. Therefore, determining that the horizontal axis current is zero at a certain moment does not immediately indicate a phase loss in the third phase stator winding of the three-phase motor. Thus, when the horizontal axis current is determined to be zero, the duration for which the horizontal axis current remains zero from the first point in time when the current is zero is defined as the first duration. Furthermore, this first duration can be recorded using a timer.

[0058] If the first duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the third phase stator winding.

[0059] Optionally, the preset duration threshold can be determined based on the output frequency cycle of the three-phase motor; in order to ensure the accuracy and timeliness of phase loss detection, the preset duration threshold can be between five and 20 output frequency cycles.

[0060] Specifically, after the first duration is recorded, if the first duration exceeds the preset duration threshold, and since both the first stator current and the second stator current are not zero, that is, the first phase stator winding corresponding to the first stator current has not experienced a phase loss, and the second phase stator winding corresponding to the second stator current has also not experienced a phase loss, then the phase loss detection result can be determined as a phase loss in the third phase stator winding.

[0061] In one embodiment, after determining whether the current value of the horizontal axis current is zero, the processor further performs the following steps when executing the computer-readable instructions:

[0062] If the current value of the horizontal axis current is not zero, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

[0063] After the first duration of recording begins, the processor, when executing the computer-readable instructions, also performs the following steps:

[0064] If the first duration does not exceed the preset duration threshold, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

[0065] Understandably, let's assume the first stator current is i. b The second stator current is i c At that time, the corresponding horizontal axis current is i as stated in the above description. α =-i b -i c If the horizontal axis current is not zero, then the current value representing the first stator current is not equal to the current value representing the second stator current, i.e., ib ≠-i c The vector sum of the first stator current, the second stator current, and the third stator current in a three-phase motor is zero. Let the third stator current be ia, which is ia + i. b +i c =0, therefore in i b ≠-i c After that, it can be determined that the third stator current ia is not zero, which means that the third phase stator winding has not lost a phase.

[0066] Furthermore, if the first duration does not exceed the preset duration threshold, that is, after the first time point, the current value of the horizontal axis current is not zero, which may be a situation that occurs instantaneously under the normal operation of the three-phase motor, then it can be determined that the phase loss detection result is that the three-phase motor has not experienced a phase loss.

[0067] In one embodiment, after determining that both the first stator current and the second stator current are not zero, the processor further performs the following steps when executing the computer-readable instructions:

[0068] Determine whether the first stator current and the second stator current satisfy the current condition that the current magnitudes are equal and the current directions are opposite;

[0069] If the first stator current and the second stator current satisfy the current condition, then starting from the time point when the current condition is satisfied, record the duration for which the current condition is continuously satisfied;

[0070] Understandably, after obtaining the first stator current and the second stator current of the three-phase motor, it can be determined whether the first stator current and the second stator current satisfy the current condition that the current magnitude is equal and the current direction is opposite. If the first stator current and the second stator current satisfy the current condition, the duration of the current condition being satisfied is recorded from the time when the current condition is satisfied.

[0071] If the duration of satisfying the current condition exceeds the preset duration threshold, then the phase loss detection result is determined to be a phase loss in the third phase stator winding.

[0072] Specifically, starting from the point when the current condition is met, the duration for which the current condition is continuously met is recorded. If the duration of meeting the current condition exceeds a preset time threshold, the phase loss detection result can be preliminarily determined to be a phase loss in the third phase stator winding. It is understandable that because the first stator current and the second stator current are detected by different current detection sensors, there may be detection errors between the first stator current and the second stator current. Therefore, the method described above for determining whether the third phase stator winding has a phase loss is less accurate than the method in this invention that checks if the current value of the horizontal axis current is zero. Therefore, the method in this invention has higher accuracy and efficiency in phase loss detection.

[0073] In one embodiment, determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes:

[0074] When the first stator current or the second stator current is determined to be zero, the zero first stator current or the zero second stator current is recorded as zero stator current; the non-zero first stator current or the non-zero second stator current is recorded as constant stator current.

[0075] Understandably, when the first stator current or the second stator current is determined to be zero, the zero stator current or the non-zero stator current is recorded as the zero stator current, and the non-zero stator current or the non-zero stator current is recorded as the constant stator current. Furthermore, if the first stator current is zero, it can be preliminarily determined that the first phase stator winding corresponding to the first stator current may be experiencing a phase loss; if the second stator current is zero, it can be preliminarily determined that the second phase stator winding corresponding to the second stator current may be experiencing a phase loss.

[0076] Determine whether the horizontal axis current and the vertical axis current meet the preset phase loss detection condition; the preset phase loss detection condition is that the ratio between the current value of the horizontal axis current and the current value of the vertical axis current is equal to a preset current coefficient.

[0077] Understandably, the preset current coefficient is Furthermore, assume the first stator current is i b The second stator current is i c At that time, the corresponding horizontal axis current is i as stated in the above description. α =-i b -i c The corresponding vertical axis current is If the first stator current is zero, then the corresponding horizontal axis current is i. α =-i c The current value of the horizontal axis current is |i α =|-i c |;The corresponding vertical axis current is The value of the vertical axis current is Therefore, when the first stator current is zero, the ratio between the horizontal axis current value and the vertical axis current value is: Furthermore, assuming the second stator current is zero, the corresponding horizontal axis current is i. α =-i b The current value of the horizontal axis current is |i α =|-i b |;The corresponding vertical axis current is The value of the vertical axis current is Therefore, when the second stator current is zero, the ratio between the horizontal axis current and the vertical axis current is also... Therefore, by judging whether the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, it can be determined whether a phase loss has occurred in the three-phase motor.

[0078] When the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the recording of the second duration begins; the second duration refers to the duration during which the horizontal axis current and the vertical axis current continuously meet the preset phase loss detection conditions starting from the second time point when the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions.

[0079] Specifically, when the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, starting from the second time point when the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the duration for which the horizontal axis current and the vertical axis current continuously meet the preset phase loss detection conditions is recorded, which is the second duration.

[0080] When the second duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the first phase stator winding or the second phase stator winding corresponding to the zero stator current, and no phase loss in the first phase stator winding or the second phase stator winding corresponding to the constant stator current.

[0081] Specifically, after the second duration is recorded, it is compared with a preset duration threshold. If the second duration exceeds the preset duration threshold, it means that the horizontal axis current and the vertical axis current continuously meet the preset phase loss detection conditions within the second duration. Thus, it can be determined that the phase loss detection result is that the first phase stator winding or the second phase stator winding corresponding to the zero stator current has a phase loss. That is, if the first stator current is the zero stator current and the second stator current is the constant stator current, then the first phase stator winding has a phase loss, and the second phase stator winding has not a phase loss. Conversely, if the first stator current is the constant stator current and the second stator current is the zero stator current, then the first phase stator winding has not a phase loss, and the second phase stator winding has a phase loss.

[0082] In one embodiment, after determining whether the horizontal axis current and the vertical axis current meet the second phase loss detection condition, the processor further performs the following steps when executing the computer-readable instructions:

[0083] If the horizontal axis current and the vertical axis current do not meet the preset phase loss detection conditions, then it is determined that the first phase stator winding and the second phase stator winding have not experienced phase loss.

[0084] The phase loss detection result of the third phase stator winding is determined based on the horizontal axis current.

[0085] After the start of recording the second duration, the following is also included:

[0086] If the second duration does not exceed the preset duration threshold, it is determined that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss.

[0087] The phase loss detection result of the third phase stator winding is determined based on the horizontal axis current.

[0088] Understandably, if the horizontal axis current and the vertical axis current do not meet the preset phase loss detection conditions, it indicates that the ratio between the current value of the horizontal axis current and the current value of the vertical axis current is not equal to the preset current coefficient. Therefore, it can be determined that the first stator current and the second stator current are not zero. This indicates that the first phase stator winding and the second phase stator winding in the three-phase motor have not experienced phase loss. Therefore, the method of determining whether the third phase stator winding is missing when the first stator current and the second stator current are not zero in the above steps can be used. That is, it is determined whether the third phase stator winding is missing based on whether the horizontal axis current is zero. The specific method has been explained in the above steps and will not be repeated here.

[0089] Furthermore, if the second duration does not exceed the preset duration threshold, it means that within the second duration, the horizontal axis current and the vertical axis current do not meet the preset phase loss detection conditions. This indicates that the horizontal axis current and the vertical axis current may instantaneously meet the preset phase loss detection conditions during normal operation of the three-phase motor, or that the first stator current or the second stator current is detected to be zero at a certain moment. Therefore, it can be determined that the first phase stator winding and the second phase stator winding in the three-phase motor have not experienced phase loss. Then, it can be determined whether the third phase stator winding has phase loss based on whether the horizontal axis current is zero. The specific method has been explained in the above steps and will not be repeated here.

[0090] In one embodiment, determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current further includes:

[0091] When both the first stator current and the second stator current are zero, the magnitude of the current vector is determined based on the horizontal axis current and the vertical axis current, and it is determined whether the magnitude of the current vector is zero.

[0092] Specifically, after obtaining the horizontal and vertical axis currents in the stationary coordinate system of the self-generating motor, the magnitude of the current vector can be determined based on the horizontal and vertical axis currents. Let the horizontal axis current be i. α The vertical axis current is i b The magnitude of the current vector is And assume the first stator current is i b The second stator current is i c When, the corresponding horizontal axis current is i α =-i b -i c The corresponding vertical axis current is If both the first stator current and the second stator current are zero, then the horizontal axis current and the vertical axis current are also zero. Therefore, the current vector amplitude is also zero. Thus, detecting whether the current vector amplitude is zero can be used as a characteristic to determine whether all stator windings of a three-phase motor have experienced phase loss.

[0093] When the current vector amplitude is zero, the recording of the third duration begins; the third duration refers to the duration during which the current vector amplitude remains zero from the third time point when the current vector amplitude is zero.

[0094] Specifically, when the current vector amplitude is zero, starting from the third time point when the current vector amplitude is zero, the duration for which the current vector amplitude remains zero is recorded, which is the third duration.

[0095] When the third duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the three-phase motor.

[0096] Specifically, when the third duration exceeds the preset duration threshold, it is determined that the first phase stator winding and the second phase stator winding are missing phases. Since in the three-phase inverter bridge circuit of the three-phase motor, if two phase stator windings are missing, all stator windings in the three-phase inverter bridge circuit are disconnected, that is, all stator windings are missing phases. At this time, the first stator current, the second stator current and the third stator current are all zero. Therefore, the phase loss detection result is that all stator windings of the three-phase motor (that is, the first phase stator winding, the second phase stator winding and the third phase stator winding) are missing phases.

[0097] In one embodiment, after starting to record the third duration, the method further includes:

[0098] If the third duration does not exceed the preset duration threshold, the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

[0099] Understandably, if the third duration does not exceed the preset duration threshold, it indicates that the current vector amplitude may be zero at a certain moment or at a certain phase angle. Within the third duration, there is a situation where the current vector amplitude is not zero, which indicates that the first stator current and the second stator current are not zero, that is, the first phase stator winding and the second phase stator winding have not experienced phase loss. Therefore, at this time, the phase loss detection result of the third phase stator winding in the three-phase motor can be determined based on the horizontal axis current. The specific implementation method has been explained in the above steps and will not be repeated here.

[0100] In one embodiment, a robot is proposed, including the aforementioned controller and a three-phase motor. The three-phase motor and the controller are both installed inside the robot housing to protect the three-phase motor and the controller, thereby improving their service life. The controller is communicatively connected to the three-phase motor to perform phase loss detection on the three-phase motor, thereby ensuring the safe start-up of the three-phase motor while protecting the safety of the robot.

[0101] In one embodiment, a three-phase motor phase loss detection method is provided. This method is applied to a controller, and the three-phase motor phase loss detection method corresponds one-to-one with the steps executed in the controller. The three-phase motor phase loss detection method specifically includes the following steps:

[0102] The first stator current and the second stator current of the three-phase motor are acquired in real time. The first stator current refers to any one of the three-phase stator currents, and the second stator current refers to any one of the three-phase stator currents that is different from the first stator current.

[0103] A stationary coordinate system for the motor is constructed based on the first stator current and the second stator current. The first stator current is decomposed in the stationary coordinate system into a first horizontal axis component current located on the horizontal axis and a first vertical axis component current located on the vertical axis. The second stator current is decomposed in the stationary coordinate system into a second horizontal axis component current located on the horizontal axis and a second vertical axis component current located on the vertical axis.

[0104] The horizontal axis current and the vertical axis current are obtained from the stationary coordinate system of the motor; the horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current.

[0105] The phase loss detection result is determined based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current.

[0106] In this embodiment, by detecting the stator current of two phase stator windings in a three-phase motor (such as the first stator current and the second stator current), and using intermediate variables corresponding to the stator current, namely the horizontal axis current and the vertical axis current, the three-phase motor is used to detect phase loss. This allows for rapid determination of whether a phase loss exists in the three-phase motor, and different phase loss conditions in the three-phase motor can be detected (such as a phase loss in one stator winding or a phase loss in all stator windings). This improves the accuracy, efficiency, and comprehensiveness of phase loss detection in three-phase motors. Furthermore, this invention does not require additional hardware processing circuitry, reducing the cost of phase loss detection in three-phase motors.

[0107] In one embodiment, constructing the motor stationary coordinate system based on the first stator current and the second stator current includes:

[0108] Establish an initial rectangular coordinate system;

[0109] The first stator current and the second stator current are generated in the initial rectangular coordinate system; the angle between the first stator current and the positive vertical axis in the initial rectangular coordinate system is a preset line segment angle; the angle between the first stator current and the second stator current is 120 degrees.

[0110] In the initial rectangular coordinate system, a horizontal axis current coinciding with the positive horizontal axis is generated. The current value of the horizontal axis current is equal to the absolute value of the sum of the predicted horizontal axis component current, the first horizontal axis component current, and the second horizontal axis component current. The predicted horizontal axis component current refers to the component current of the predicted stator current on the horizontal axis. The predicted stator current is determined based on the first stator current and the second stator current. The direction of the horizontal axis current is positive.

[0111] In the initial rectangular coordinate system, a vertical axis current is generated that coincides with the positive vertical axis. The current value of the vertical axis current is equal to the absolute value of the sum of the predicted vertical axis component current, the first vertical axis component current, and the second vertical axis component current. The predicted vertical axis component refers to the component current of the predicted stator current on the vertical axis. The direction of the vertical axis current is positive.

[0112] The initial rectangular coordinate system containing the horizontal axis current and the vertical axis current is recorded as the motor stationary coordinate system.

[0113] In one embodiment, the first stator current starts from the origin of the initial rectangular coordinate system and extends toward the second quadrant, and the second stator current starts from the origin of the initial rectangular coordinate system and extends toward the third quadrant; the preset line segment angle is 30 degrees, the predicted horizontal axis component current is equal to the predicted stator current, and the predicted vertical axis component current is equal to zero.

[0114] In one embodiment, determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes:

[0115] After determining that both the first stator current and the second stator current are not zero, determine whether the current value of the horizontal axis current is zero;

[0116] If the current value of the horizontal axis current is zero, then the first duration of recording begins; the first duration of recording refers to the duration during which the current value of the horizontal axis current remains zero from the first time point when the current value of the horizontal axis current is zero.

[0117] If the first duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the third phase stator winding. The third phase stator winding refers to the stator winding corresponding to the third stator current. The third stator current refers to the stator current other than the first stator current and the second stator current among the three phase stator currents.

[0118] In one embodiment, after determining whether the current value of the horizontal axis current is zero, the method further includes:

[0119] If the current value of the horizontal axis current is not zero, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

[0120] After the start of recording the first duration, the process also includes:

[0121] If the first duration does not exceed the preset duration threshold, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

[0122] In one embodiment, the first stator current corresponds to the first phase stator winding in the three-phase motor; the second stator current corresponds to the second phase stator winding in the three-phase motor; step S40 further includes:

[0123] When the first stator current or the second stator current is determined to be zero, the zero first stator current or the zero second stator current is recorded as zero stator current; the non-zero first stator current or the non-zero second stator current is recorded as constant stator current.

[0124] Determine whether the horizontal axis current and the vertical axis current meet the preset phase loss detection condition; the preset phase loss detection condition is that the ratio between the current value of the horizontal axis current and the current value of the vertical axis current is equal to a preset current coefficient.

[0125] When the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the recording of the second duration begins; the second duration refers to the duration during which the horizontal axis current and the vertical axis current continuously meet the preset phase loss detection conditions starting from the second time point when the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions.

[0126] When the second duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the first phase stator winding or the second phase stator winding corresponding to the zero stator current, and no phase loss in the first phase stator winding or the second phase stator winding corresponding to the constant stator current.

[0127] In one embodiment, after determining whether the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the process includes:

[0128] If the horizontal axis current and the vertical axis current do not meet the preset phase loss detection conditions, then it is determined that the first phase stator winding and the second phase stator winding have not experienced phase loss.

[0129] Based on the horizontal axis current, determine the phase loss detection result of the third phase stator winding in the three-phase motor.

[0130] In one embodiment, after starting to record the third duration, the method further includes:

[0131] If the second duration does not exceed the preset duration threshold, it is determined that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss.

[0132] Based on the horizontal axis current, determine the phase loss detection result of the third phase stator winding in the three-phase motor.

[0133] In one embodiment, determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes:

[0134] When both the first stator current and the second stator current are zero, the magnitude of the current vector is determined based on the horizontal axis current and the vertical axis current, and it is determined whether the magnitude of the current vector is zero.

[0135] When the current vector amplitude is zero, the recording of the third duration begins; the third duration refers to the duration during which the current vector amplitude remains zero from the third time point when the current vector amplitude is zero.

[0136] When the third duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the three-phase motor.

[0137] In one embodiment, the first stator current corresponds to the first phase stator winding in the three-phase motor; the second stator current corresponds to the second phase stator winding in the three-phase motor.

[0138] After the start of recording the third duration, the following is included:

[0139] When the third duration does not exceed the preset duration threshold, the phase loss detection result is determined to be that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss.

[0140] Based on the horizontal axis current, determine the phase loss detection result of the third phase stator winding in the three-phase motor.

[0141] It should be understood that the sequence number of each step in the above embodiments does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.

[0142] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored, which, when executed by a processor, implements the three-phase motor phase loss detection method described in the above embodiment.

[0143] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0144] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0145] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A controller characterized by comprising: The controller is connected to a three-phase motor, which includes a first-phase stator winding, a second-phase stator winding, and a third-phase stator winding. The controller includes a memory, a processor, and computer-readable instructions stored in the memory and executable on the processor. When the processor executes the computer-readable instructions, it performs the following steps: The first stator current of the first phase stator winding and the second stator current of the second phase stator winding are acquired in real time. A stationary coordinate system for the motor is constructed based on the first stator current and the second stator current. The first stator current is decomposed in the stationary coordinate system into a first horizontal axis component current located on the horizontal axis and a first vertical axis component current located on the vertical axis. The second stator current is decomposed in the stationary coordinate system into a second horizontal axis component current located on the horizontal axis and a second vertical axis component current located on the vertical axis. Obtain the horizontal axis current and the vertical axis current from the motor stationary coordinate system; The horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current. The phase loss detection result is determined based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current. The step of determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes: After determining that both the first stator current and the second stator current are not zero, determine whether the current value of the horizontal axis current is zero; If the current value of the horizontal axis current is zero, then the first duration of recording begins; the first duration of recording refers to the duration during which the current value of the horizontal axis current remains zero from the first time point when the current value of the horizontal axis current is zero. If the first duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the third phase stator winding.

2. The controller as described in claim 1, characterized in that, The process of constructing a stationary coordinate system for the motor based on the first stator current and the second stator current includes: Establish an initial rectangular coordinate system; The first stator current and the second stator current are generated in the initial rectangular coordinate system; the angle between the first stator current and the positive vertical axis in the initial rectangular coordinate system is a preset line segment angle; the angle between the first stator current and the second stator current is 120 degrees. In the initial rectangular coordinate system, a horizontal axis current coinciding with the positive horizontal axis is generated. The current value of the horizontal axis current is equal to the absolute value of the sum of the predicted horizontal axis component current, the first horizontal axis component current, and the second horizontal axis component current. The predicted horizontal axis component current refers to the component current of the predicted stator current on the horizontal axis. The predicted stator current is determined based on the first stator current and the second stator current. The direction of the horizontal axis current is positive. In the initial rectangular coordinate system, a vertical axis current is generated that coincides with the positive vertical axis. The current value of the vertical axis current is equal to the absolute value of the sum of the predicted vertical axis component current, the first vertical axis component current, and the second vertical axis component current. The predicted vertical axis component refers to the component current of the predicted stator current on the vertical axis. The direction of the vertical axis current is positive. The initial rectangular coordinate system containing the horizontal axis current and the vertical axis current is recorded as the motor stationary coordinate system.

3. The controller of claim 2, wherein, The first stator current starts from the origin of the initial rectangular coordinate system and extends toward the second quadrant; the second stator current starts from the origin of the initial rectangular coordinate system and extends toward the third quadrant. The preset line segment angle is 30 degrees, the predicted horizontal axis component current is equal to the predicted stator current, and the predicted vertical axis component current is equal to zero.

4. The controller as described in claim 1, characterized in that, After determining whether the current value of the horizontal axis current is zero, the processor, when executing the computer-readable instructions, further performs the following steps: If the current value of the horizontal axis current is not zero, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss. After the first duration of recording begins, the processor, when executing the computer-readable instructions, also performs the following steps: If the first duration does not exceed the preset duration threshold, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

5. The controller of claim 1, wherein, The step of determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes: When the first stator current or the second stator current is determined to be zero, the first stator current or the second stator current that is zero is recorded as zero stator current, and the first stator current or the second stator current that is not zero is recorded as constant stator current. Determine whether the horizontal axis current and the vertical axis current meet the preset phase loss detection condition; the preset phase loss detection condition is that the ratio between the current value of the horizontal axis current and the current value of the vertical axis current is equal to a preset current coefficient. When the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the recording of the second duration begins; the second duration refers to the duration during which the preset phase loss detection conditions are continuously met starting from the second time point when the preset phase loss detection conditions are met. When the second duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the first phase stator winding or the second phase stator winding corresponding to the zero stator current, and no phase loss in the first phase stator winding or the second phase stator winding corresponding to the constant stator current.

6. The controller of claim 5, wherein, After determining whether the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the processor further performs the following steps when executing the computer-readable instructions: If the horizontal axis current and the vertical axis current do not meet the preset phase loss detection conditions, then it is determined that the first phase stator winding and the second phase stator winding have not experienced phase loss. The phase loss detection result of the third phase stator winding is determined based on the horizontal axis current.

7. The controller of claim 5, wherein, After the second duration of recording begins, the processor, when executing the computer-readable instructions, also performs the following steps: If the second duration does not exceed the preset duration threshold, it is determined that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss. The phase loss detection result of the third phase stator winding is determined based on the horizontal axis current.

8. The controller of claim 1, wherein, The step of determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes: When both the first stator current and the second stator current are zero, the magnitude of the current vector is determined based on the horizontal axis current and the vertical axis current, and it is determined whether the magnitude of the current vector is zero. When the current vector amplitude is zero, the recording of the third duration begins; the third duration refers to the duration during which the current vector amplitude remains zero from the third time point when the current vector amplitude is zero. When the third duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the first phase stator winding, the second phase stator winding, and the third phase stator winding.

9. The controller of claim 8, wherein, After the third duration of recording begins, the processor, when executing the computer-readable instructions, also performs the following steps: When the third duration does not exceed the preset duration threshold, the phase loss detection result is determined to be that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss. The phase loss detection result of the third phase stator winding is determined based on the horizontal axis current.

10. A robot, characterized in that Includes the controller as described in any one of claims 1 to 9.

11. A method of open-phase detection for a three-phase electric motor, the method comprising: include: The first stator current and the second stator current of the three-phase motor are acquired in real time. The first stator current refers to any one of the three-phase stator currents, and the second stator current refers to any one of the three-phase stator currents that is different from the first stator current. A stationary coordinate system for the motor is constructed based on the first stator current and the second stator current. The first stator current is decomposed in the stationary coordinate system into a first horizontal axis component current located on the horizontal axis and a first vertical axis component current located on the vertical axis. The second stator current is decomposed in the stationary coordinate system into a second horizontal axis component current located on the horizontal axis and a second vertical axis component current located on the vertical axis. Obtain the horizontal axis current and the vertical axis current from the motor stationary coordinate system; The horizontal axis current is determined based on the first horizontal axis component current and the second horizontal axis component current, and the vertical axis current is determined based on the first vertical axis component current and the second vertical axis component current. The phase loss detection result is determined based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current. The step of determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes: After determining that both the first stator current and the second stator current are not zero, determine whether the current value of the horizontal axis current is zero; If the current value of the horizontal axis current is zero, then the first duration of recording begins; the first duration of recording refers to the duration during which the current value of the horizontal axis current remains zero from the first time point when the current value of the horizontal axis current is zero. If the first duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the third phase stator winding. The third phase stator winding refers to the stator winding corresponding to the third stator current. The third stator current refers to the stator current other than the first stator current and the second stator current among the three phase stator currents.

12. The three-phase motor open-phase detection method of claim 11, wherein, The process of constructing a stationary coordinate system for the motor based on the first stator current and the second stator current includes: Establish an initial rectangular coordinate system; The first stator current and the second stator current are generated in the initial rectangular coordinate system; the angle between the first stator current and the positive vertical axis in the initial rectangular coordinate system is a preset line segment angle; the angle between the first stator current and the second stator current is 120 degrees. In the initial rectangular coordinate system, a horizontal axis current coinciding with the positive horizontal axis is generated. The current value of the horizontal axis current is equal to the absolute value of the sum of the predicted horizontal axis component current, the first horizontal axis component current, and the second horizontal axis component current. The predicted horizontal axis component current refers to the component current of the predicted stator current on the horizontal axis. The predicted stator current is determined based on the first stator current and the second stator current. The direction of the horizontal axis current is positive. In the initial rectangular coordinate system, a vertical axis current is generated that coincides with the positive vertical axis. The current value of the vertical axis current is equal to the absolute value of the sum of the predicted vertical axis component current, the first vertical axis component current, and the second vertical axis component current. The predicted vertical axis component refers to the component current of the predicted stator current on the vertical axis. The direction of the vertical axis current is positive. The initial rectangular coordinate system containing the horizontal axis current and the vertical axis current is recorded as the motor stationary coordinate system.

13. The method of claim 12, wherein, The first stator current starts from the origin of the initial rectangular coordinate system and extends toward the second quadrant; the second stator current starts from the origin of the initial rectangular coordinate system and extends toward the third quadrant. The preset line segment angle is 30 degrees, the predicted horizontal axis component current is equal to the predicted stator current, and the predicted vertical axis component current is equal to zero.

14. The three-phase motor open-phase detection method of claim 11, wherein, After determining whether the current value of the horizontal axis current is zero, the process further includes: If the current value of the horizontal axis current is not zero, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss. After the start of recording the first duration, the process also includes: If the first duration does not exceed the preset duration threshold, then the phase loss detection result is determined to be that the three-phase motor has not experienced a phase loss.

15. The three-phase motor open-phase detection method of claim 11, wherein, The first stator current is the same as the real-time current of the first phase stator winding in the three-phase motor; the second stator current is the same as the real-time current of the second phase stator winding in the three-phase motor; The step of determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes: When the first stator current or the second stator current is determined to be zero, the zero first stator current or the zero second stator current is recorded as zero stator current; the non-zero first stator current or the non-zero second stator current is recorded as constant stator current. Determine whether the horizontal axis current and the vertical axis current meet the preset phase loss detection condition; the preset phase loss detection condition is that the ratio between the current value of the horizontal axis current and the current value of the vertical axis current is equal to a preset current coefficient. When the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the recording of the second duration begins; the second duration refers to the duration during which the horizontal axis current and the vertical axis current continuously meet the preset phase loss detection conditions starting from the second time point when the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions. When the second duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the first phase stator winding or the second phase stator winding corresponding to the zero stator current, and no phase loss in the first phase stator winding or the second phase stator winding corresponding to the constant stator current.

16. The method of open-phase detection of a three-phase electric motor of claim 15, wherein, After determining whether the horizontal axis current and the vertical axis current meet the preset phase loss detection conditions, the process includes: If the horizontal axis current and the vertical axis current do not meet the preset phase loss detection conditions, then it is determined that the first phase stator winding and the second phase stator winding have not experienced phase loss. Based on the horizontal axis current, determine the phase loss detection result of the third phase stator winding in the three-phase motor.

17. The three-phase motor open-phase detection method of claim 15, wherein, After the start of recording the second duration, the following is also included: If the second duration does not exceed the preset duration threshold, it is determined that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss. Based on the horizontal axis current, determine the phase loss detection result of the third phase stator winding in the three-phase motor.

18. The three-phase motor open-phase detection method of claim 11, wherein, The step of determining the phase loss detection result based on the first stator current, the second stator current, the horizontal axis current, and the vertical axis current includes: When both the first stator current and the second stator current are zero, the magnitude of the current vector is determined based on the horizontal axis current and the vertical axis current, and it is determined whether the magnitude of the current vector is zero. When the current vector amplitude is zero, the recording of the third duration begins; the third duration refers to the duration during which the current vector amplitude remains zero from the third time point when the current vector amplitude is zero. When the third duration exceeds a preset duration threshold, the phase loss detection result is determined to be a phase loss in the three-phase motor.

19. The method for detecting phase loss in a three-phase motor as described in claim 18, characterized in that, The first stator current is the same as the real-time current of the first phase stator winding in the three-phase motor; the second stator current is the same as the real-time current of the second phase stator winding in the three-phase motor; After the start of recording the third duration, the following is included: When the third duration does not exceed the preset duration threshold, the phase loss detection result is determined to be that neither the first phase stator winding nor the second phase stator winding has experienced a phase loss. Based on the horizontal axis current, determine the phase loss detection result of the third phase stator winding in the three-phase motor. 20.A computer readable storage medium, storing a computer program, wherein, The computer program, when executed by a processor, implements the three-phase motor open-phase detection method according to any one of claims 11 to 19.

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