Self-checking control method for related breaker

Abstract

The invention provides a self-checking control method for a relay breaker. The method is suitable for a dual-redundancy electric power steering system in a vehicle. The dual-redundancy electric power steering system comprises a first motor winding and a second motor winding. The self-checking control method for the relay breaker comprises the following steps: a cooperative control step: cooperatively controlling a first motor winding and a second motor winding so as to enable the total output torque of the first motor winding and the second motor winding to be 0; and a related breaker self-checking step: controlling related breakers of each phase of the first motor winding and the second motor winding so as to execute related breaker self-checking according to the current value of each phase.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control, and more particularly to a method for self-checking control of a related breaker. Background Art

[0002] Currently, a dual-redundant electric power steering device is often used in vehicles to assist the axial torque of the vehicle driver by a motor. For example, the patent document CN 109843701A provides a dual-redundant electric power steering device. This dual-redundant electric power steering device uses two sets of control units to independently control two sets of motor windings to generate assist torques respectively. These two sets of control units respectively include components such as a microcontroller unit (MCU for short), a drive circuit, an inverter bridge, and a related breaker (or phase switch, phase relay) for connecting the motor and the controller. The two sets of motor windings are two sets of three-phase armature windings of a permanent magnet synchronous motor, and their structures are generally the same. In addition, for the related breaker, a metal-oxide-semiconductor field effect transistor (MOSFET for short) switching device is generally used in the steering system. Each phase of each set of three-phase motor windings is connected to the control unit through a MOSFET. Summary of the Invention

[0003] Embodiments of the present disclosure provide a method for self-checking control of a related breaker, eliminating the undesired torque and motor rotation brought by applying the traditional self-checking method of switching devices to the self-checking of the related breaker in an electric power steering device.

[0004] The method for self-checking control of a related breaker provided by the embodiments of the present disclosure is applicable to a dual-redundant electric power steering system in a vehicle. The dual-redundant electric power steering system includes a first motor winding and a second motor winding. The method for self-checking control of a related breaker includes: a collaborative control step of collaboratively controlling the first motor winding and the second motor winding so that the total output torque of the first motor winding and the second motor winding is 0; and a related breaker self-checking step of controlling the related breakers of each phase of the first motor winding and the second motor winding to perform a related breaker self-check according to the current value of each phase. In one embodiment, the collaborative control step of the method for self-checking control of a related breaker of the present disclosure includes: collaboratively setting the duty ratios of the first motor winding and the second motor winding so that the total output torque of the first motor winding and the second motor winding is 0.

[0005] In one embodiment, the relevant breaker self-checking steps of the relevant breaker self-checking control method of the present disclosure include: simultaneously turning off / energizing the relevant breakers of each phase of the first motor winding and the second motor winding; collecting the current values of each phase of the first motor winding and the second motor winding; when performing the turn-off self-check, for the first motor winding and the second motor winding, respectively determine whether the largest one among the current values of each phase is less than the current threshold. If the largest one is less than the current threshold, the turn-off is successful; otherwise, the turn-off fails. When performing the energizing self-check, sequentially perform the energizing self-check for each phase of the three phases of the first motor winding and the second motor winding respectively, and the phase currently being self-checked is the current target phase. Respectively determine whether the current value of the current target phase of the first motor winding and the second motor winding is greater than the current threshold. If the current value of the current target phase is greater than the current threshold, the current target phase is successfully energized; otherwise, the current target phase fails to energize.

[0006] In one embodiment, when performing the turn-off self-check, the collaborative control steps of the relevant breaker self-checking control method of the present disclosure include: driving the first motor winding and the second motor winding according to the first set of three-phase duty cycles and maintaining for the first time period. The first set of three-phase duty cycles makes the sum of the duty cycles of each phase of the first motor winding and the corresponding phase of the second motor winding equal to 1; and driving the first motor winding and the second motor winding according to the second set of three-phase duty cycles and maintaining for the second time period. The second set of three-phase duty cycles is different from the first set of three-phase duty cycles, but still makes the sum of the duty cycles of each phase of the first motor winding and the corresponding phase of the second motor winding equal to 1. The relevant breaker self-checking steps include: during the first time period, respectively collecting the first set of current values of each phase of the first motor winding and the second motor winding; during the second time period, respectively collecting the second set of current values of each phase of the first motor winding and the second motor winding; and respectively for the first motor winding and the second motor winding, determining the maximum value among the first set of current values of each phase and the second set of current values of each phase as the largest one among the current values of each phase.

[0007] In one embodiment, when performing the energizing self-check, the collaborative control steps of the relevant breaker self-checking control method of the present disclosure include: collaboratively setting the duty cycles of the first motor winding and the second motor winding, such that the duty cycle of the current target phase of the first motor winding is x, the duty cycles of the other two phases of the first motor winding are both 1 - x, and the duty cycle of the current target phase of the second motor winding is 1 - x, and the duty cycles of the other two phases of the second motor winding are both x, where 0.5 < x ≤ 0.6; and driving the first motor winding and the second motor winding according to the set duty cycles within a predetermined time period. The relevant breaker self-checking steps include: during the predetermined time period, respectively collecting the current values of the current target phases of the first motor winding and the second motor winding.

[0008] According to the relevant breaker self-check control method of the embodiments of the present disclosure, the total output torque of the first motor winding and the second motor winding of the dual-redundant electric power steering system is made zero through a collaborative control step. When the total output torque of the first motor winding and the second motor winding is zero, a relevant breaker self-check step is executed to self-check the relevant breakers of each phase of the first motor winding and the second motor winding according to the phase current values, thereby avoiding unexpected torque and motor rotation during the relevant breaker self-check process; by collaboratively setting the duty cycles of the first motor winding and the second motor winding, the sum of the duty cycle of each phase of the first motor winding and the corresponding phase of the second motor winding is always 1. The two motor windings generate currents with the same magnitude and opposite directions, and then generate torques with opposite directions to cancel each other out, so that the total output torque of the first motor winding and the second motor winding is zero; in addition, when self-checking each group of relevant breakers, two sets of duty cycles are alternately given, so that the current directions of two phases of the three-phase windings are changed successively, preventing omissions in the self-check of the disconnection of the relevant breakers. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present invention can be better understood from the following description of the specific embodiments in conjunction with the accompanying drawings, wherein:

[0010] Figure 1 FIG. shows a schematic block diagram of a dual-redundant electric power steering system according to an embodiment of the present disclosure.

[0011] Figure 2 FIG. shows a schematic flow chart of a relevant breaker self-check control method according to an embodiment of the present disclosure.

[0012] Figure 3 FIG. shows a flow chart of the turn-off self-check process of a relevant breaker according to an embodiment of the present disclosure.

[0013] Figure 4 FIG. shows a flow chart of the closing self-check process of a relevant breaker according to an embodiment of the present disclosure.

[0014] Figure 5 FIG. shows a schematic block diagram of an electronic device used in a vehicle according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0015] Aspects and exemplary embodiments of the present invention will be described in detail below. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is only provided to better understand the present invention by showing examples of the present invention. The present invention is in no way limited to any specific configuration and algorithm set forth below, but covers any modifications, substitutions, and improvements of elements, components, and algorithms without departing from the spirit of the present invention. Well-known structures and technologies are not shown in the drawings and the following description so as to avoid unnecessarily obscuring the present invention.

[0016] In addition, it should be noted that the term "A is connected to B" used herein may mean that "A is directly connected to B" or that "A is indirectly connected to B via one or more other elements". In this document, the term "a" or "an" is used to include one or more than one, independent of any other instances or uses of "at least one" or "one or more". In this document, the term "or" is used to refer to a non-exclusive or, so that "A or B" includes "A, but not B", "B, but not A", and "A and B", unless otherwise indicated. In addition, in the appended claims, the terms "first", "second", "third", etc. are used only as labels and are not intended to imply a numerical order for their objects.

[0017] In vehicles, a dual-redundant electric power steering device is often used to assist the axial torque of the vehicle driver by a motor. In a dual-redundant system including a dual-redundant electric power steering device, when a set of control units fails, the connection between the set of control units and the corresponding motor winding can be cut off by a related breaker to isolate the motor winding from the electrical system, and the corresponding motor winding can be continuously driven by the other normal set of control units to generate an assist torque. Therefore, in such a dual-redundant system, the related breaker is a very important safety device, and it is required that the related breaker can accurately and timely respond to the disconnection command or closing command issued by the control unit. During the self-check of the related breaker, it is necessary to judge whether the related breaker can be normally switched on and off.

[0018] If the traditional self - checking method of switching devices is used to implement the self - checking of relevant breakers in a dual - redundant electric power steering device, the specific process includes, for example: applying a certain voltage to the relevant breaker, and then sending a disconnection command to it to detect whether current is generated. If current is generated, the relevant breaker is short - circuited and cannot be disconnected; alternatively, sending a closing command to it to detect whether current is generated. If no current is generated, the relevant breaker is open - circuited and cannot be closed. When the relevant breaker is self - checked through such a process, during the self - checking period, current will be generated when the relevant breaker closes. Since the relevant breaker is connected to the motor, the current will flow through the motor winding, thereby generating torque and causing the motor to rotate. For a power steering device, there is no torque request during the self - checking of the relevant breaker, and the motor should not generate any torque but should remain stationary. This unexpected torque and motor rotation do not meet the design and safety requirements and may also cause unexpected rotation of the steering wheel.

[0019] To eliminate the unexpected torque and motor rotation caused by applying the traditional self - checking method of switching devices to the self - checking of relevant breakers in an electric power steering device, the traditional approach is to reduce the voltage applied during self - checking until the generated torque cannot overcome the friction of the motor itself, thereby achieving motor stillness. However, in this case, the generated current will be very small, resulting in little difference in current between the open and closed states of the relevant breaker, making it difficult to distinguish the conduction state of the relevant breaker through the current. That is to say, although the motor stillness is achieved, the function of the self - checking itself is sacrificed.

[0020] Embodiments of the present application provide a method for self - checking relevant breakers, which is applicable to a dual - redundant system or a dual - electronic - control system that needs to keep the motor torque - free during the self - checking of relevant breakers. For example, a dual - redundant electric power steering system, especially a dual - redundant electric power steering system with a six - phase permanent - magnet synchronous motor or two three - phase permanent - magnet synchronous motors.

[0021] For convenience, by way of illustration and not limitation, the present application will describe the proposed self - checking control method for relevant breakers by taking a dual - redundant electric power steering system as an example.

[0022] Figure 1 A schematic block diagram of a dual - redundant electric power steering system 100 according to an embodiment of the present disclosure is shown. It should be noted that Figure 1 only the components and signal flows related to the technical solution of the present application in the dual - redundant electric power steering system are shown, and other components and signal flows function as commonly used in the art and will not be elaborated herein.

[0023] As Figure 1As shown, the dual-redundant electric power steering system 100 includes two sets of control units that are substantially the same, namely the first control unit 110 and the second control unit 120, which are respectively used to independently control the first motor winding 130 and the second motor winding 140. The first motor winding 130 and the second motor winding 140 can be, for example, two windings of a six-phase permanent magnet synchronous motor (PMSM), or the windings of two three-phase PMSMs.

[0024] As Figure 1 As shown, the first control unit 110 may include a first MCU (MCU1), a first gate driver (GDU1), a first bridge arm module (B61), a first disconnector (PD1), a first phase current sampler (S1), and a first disconnector driver chip (PDD1); correspondingly, the second control unit 120 may include a second MCU (MCU2), a second gate driver (GDU2), a second bridge arm module (B62), a second disconnector (PD2), a second phase current sampler (S2), and a second disconnector driver chip (PDD2).

[0025] The U-phase, V-phase, and W-phase of the first motor winding 130 are respectively represented by U1, V1, and W1, and the U-phase, V-phase, and W-phase of the second motor winding 140 are respectively represented by U2, V2, and W2.

[0026] The first bridge arm module B61 and the second bridge arm module B62 each include a U-phase, a V-phase, and a W-phase, and each phase is composed of two switching elements, namely the upper bridge and the lower bridge, and their duty cycles are complementary. The switching elements used in the embodiments of the present application may include, for example, MOSFETs, contactors such as mechanical switches, or insulated-gate bipolar transistors (IGBTs), etc.

[0027] The first disconnector PD1 and the second disconnector PD2 each include three switching elements (for example, MOSFETs, contactors, or IGBTs, etc.), which are respectively represented as PDu1, PDv1, PDw1 and PDu2, PDv2, PDw2.

[0028] The first MCU MCU1 sends a control instruction to the first gate driver GDU1, so that the first gate driver GDU1 drives the first bridge arm module B61 to control the U-phase, V-phase, and W-phase (i.e., U1, V1, W1) of the first motor winding 130 by controlling the opening and closing of the first disconnector PD1.

[0029] The second MCU, MCU2, sends control instructions to the second gate driver, GDU2, causing the second gate driver, GDU2, to drive the second leg module, B62, to control the U-phase, V-phase, and W-phase (i.e., U2, V2, W2) of the second motor winding 230 by controlling the opening of the second associated disconnect PD2.

[0030] The first-phase current sampler, S1, is used to collect the first set of phase current values, PCu1, PCv1, and PCw1, after being processed by the first gate driver, GDU1. The second-phase current sampler, S2, is used to collect the second set of phase current values, PCu2, PCv2, and PCw2, after being processed by the second gate driver, GDU2.

[0031] The disconnect self-check includes a turn-off self-check phase and a pull-in self-check phase. Generally, the turn-off self-check is performed first, followed by the pull-in self-check. For example, for Figure 1 the shown dual-redundant electric power steering system, before the disconnect self-check, it is necessary to ensure that all other components are operating normally.

[0032] Next, the method for disconnect self-check of the present application will be described by taking the Figure 1 shown dual-redundant electric power steering system as an example.

[0033] Figure 2 FIG. shows a schematic flowchart of a disconnect self-check control method 200 according to an embodiment of the present disclosure. The disconnect self-check control method 200 can be applied to a dual-redundant electric power steering system 100 as shown in Figure 1 FIG.

[0034] The disconnect self-check control method 200 includes a co-control step in block 210, co-controlling the first motor winding and the second motor winding so that the total output torque of the first motor winding and the second motor winding is 0. For example, in Figure 1 FIG., the first motor winding 130 and the second motor winding 140 are co-controlled to make their total output torque 0.

[0035] As shown in the reference Figure 1As described above, in a dual-redundant electric power steering system, the first control unit and the second control unit independently control the first motor winding and the second motor winding respectively. In one implementation, an additional total control unit can be configured to control the first control unit and the second control unit to achieve coordinated control of the first motor winding and the second motor winding. In another implementation, one of the first control unit and the second control unit can be used as the main control unit and the other as the slave control unit to achieve coordinated control of the first motor winding and the second motor winding. In yet another implementation, the first control unit and the second control unit can be coordinated and programmed so that the control of the first control unit over the first motor winding and the control of the second control unit over the second motor winding can be coordinated.

[0036] In some embodiments, the coordinated control of the first motor winding and the second motor winding includes coordinately setting the duty cycles of the first motor winding and the second motor winding so that the total output torque of the first motor winding and the second motor winding is 0. For example, the sum of the duty cycles of each phase of the first motor winding and the corresponding phase of the second motor winding is set to 1, so that the torques generated by the first motor winding and the second motor winding are equal in magnitude and opposite in direction, and the two cancel each other out, making the total output torque of the motor 0.

[0037] The related breaker self-check control method 200 includes the related breaker self-check step in block 220, controlling the related breakers of each phase of the first motor winding and the second motor winding to perform the related breaker self-check according to the current values of each phase. For example, Figure 1 in the case where the total output torque of the first motor winding 130 and the second motor winding 140 is 0, the first related breaker PD1 and the second related breaker PD2 are respectively controlled to perform self-check on the first related breaker PD1 and the second related breaker PD2 according to the first set of phase current values PCu1, PCv1, PCw1 collected by the first phase current sampler S1 and the second set of phase current values PCu2, PCv2, PCw2 collected by the second phase current sampler S2.

[0038] It should be noted that when performing self-check on the related breaker, generally, the turn-off self-check is performed first, and then the pull-in self-check is performed. However, according to actual needs, the pull-in self-check can also be performed first, and then the turn-off self-check.

[0039] The above-mentioned disconnector self-check control method of the present disclosure considers each group of three-phase disconnectors as a whole, which can effectively simplify the self-check steps and save self-check time. Taking the turn-off self-check as an example, for a total of 6 disconnectors in two groups of three-phase disconnectors, a disconnection instruction is sent simultaneously, rather than disconnecting one phase by one phase. The above-mentioned disconnector self-check control method of the present disclosure utilizes the dual redundant system and the characteristics of the motor, and applies voltages to the two groups of disconnectors in a specific manner during the self-check of the disconnectors, so that the torques generated on the three-phase windings of the two groups of motors are equal in magnitude and opposite in direction, thereby canceling each other out, and making the total output torque of the motor 0.

[0040] The following will combine Figure 3 and Figure 4 to introduce the turn-off self-check process and the pull-in self-check process of the disconnector in detail.

[0041] Figure 3 Fig. shows a flowchart of a turn-off self-check process 300 of a disconnector according to an embodiment of the present disclosure.

[0042] During the turn-off self-check, for the first motor winding and the second motor winding, it is respectively determined whether the maximum value among the phase current values of each phase is less than the current threshold. If the maximum value is less than the current threshold, the turn-off is successful; otherwise, the turn-off fails.

[0043] The turn-off self-check process 300 starts at block 310. At block 310, the first disconnector drive chip PDD1 and the second disconnector drive chip PDD2 respectively send disconnection instructions to the first disconnector PD1 and the second disconnector PD2.

[0044] The turn-off self-check process 300 includes, at block 320, the first MCU MCU1 sending the first three-phase duty ratio instructions DTu1, DTv1, DTw1 to the first gate driver GDU1, and at the same time the second MCU MCU2 sending the second three-phase duty ratio instructions DTu2, DTv2, DTw2 to the second gate driver GDU2, where the first three-phase duty ratio instructions DTu1, DTv1, DTw1 specify the duty ratios of the U phase, V phase, and W phase of the first motor winding, and the second three-phase duty ratio instructions DTu2, DTv2, DTw2 specify the duty ratios of the U phase, V phase, and W phase of the second motor winding, and the sum of the duty ratios of each phase specified in the first three-phase duty ratio instructions DTu1, DTv1, DTw1 and the corresponding phase specified in the second three-phase duty ratio instructions DTu2, DTv2, DTw2 is 1.

[0045] As pointed out above, the duty ratios of the upper bridge and the lower bridge included in each phase of the first bridge arm module B61 and the second bridge arm module B62 are complementary, so it is only necessary to send a duty ratio instruction to one of the bridges (e.g., the upper bridge or the lower bridge).

[0046] To ensure that the total output torque of the vehicle's motor is 0, it is necessary to ensure that the sum of the duty ratios of each phase specified in the first three-phase duty ratio commands DTu1, DTv1, and DTw1 sent by the first MCU MCU1 and the corresponding duty ratios of the corresponding phases in the second three-phase duty ratio commands DTu2, DTv2, and DTw2 sent by the second MCU MCU2 is 1. For example, assuming that the duty ratios of DTu1, DTv1, and DTw1 are set to x, 1 - x, and 1 - x respectively, then the duty ratios of DTu2, DTv2, and DTw2 should be set to 1 - x, x, and x respectively, where x is a value greater than or equal to 0 and less than or equal to 1 (0 ≤ x ≤ 1). The value of x is related to the magnitude of the current that the system in the actual application wants to generate, and generally takes a value of 0.5 < x ≤ 0.6. For example, the default value can be taken as 0.5. The specific value of x depends on the characteristics of the motor and the phase current sensor.

[0047] The turn-off self-check process 300 then includes, at block 330, causing the first gate driver GDU1 and the second gate driver GDU2 to drive the first bridge arm module B61 and the second bridge arm module B62 according to the duty ratios specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the second three-phase duty ratio commands DTu2, DTv2, DTw2 for a first time period, and detecting the first set of phase current values PCu1, PCv1, PCw1 collected by the first phase current sampler S1 and the second set of phase current values PCu2, PCv2, PCw2 collected by the second phase current sampler S2 during this first time period.

[0048] The turn-off self-check process 300 further includes, at block 340, after the first time period, the first MCU MCU1 and the second MCU MCU2, while ensuring that the sum of the duty ratios of each phase in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the corresponding duty ratios of the corresponding phases in the second three-phase duty ratio commands DTu2, DTv2, DTw2 sent by the second MCU MCU2 is still 1, respectively adjust the duty ratios specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the duty ratios specified in the second three-phase duty ratio commands DTu2, DTv2, DTw2.

[0049] For example, the first MCU MCU1 can adjust the duty ratios of DTu1, DTv1, and DTw1 from x, 1 - x, and 1 - x to 1 - x, x, and 1 - x, while the second MCU MCU2 can adjust the duty ratios of DTu2, DTv2, and DTw2 from 1 - x, x, and x to x, 1 - x, and x.

[0050] The turn-off self-check process 300 further includes, at block 350, causing the first gate driver GDU1 and the second gate driver GDU2 to drive the first leg module B61 and the second leg module B62 at the adjusted duty cycles specified by the first three-phase duty cycle commands DTu1, DTv1, DTw1 and the second three-phase duty cycle commands DTu2, DTv2, DTw2 for a second time period, and detecting, during this second time period, the first set of phase current values PCu1’, PCv1’, PCw1’ collected by the first phase current sampler S1 and the second set of phase current values PCu2’, PCv2’, PCw2’ collected by the second phase current sampler S2 respectively.

[0051] The first time period and the second time period can be determined according to the actual application, generally being several tens of milliseconds, such as 50 to 100 milliseconds (including the end values).

[0052] The turn-off self-check process 300 further includes, at block 360, determining the largest one among the phase current values PCu1, PCv1, PCw1 detected during the first time period and the phase current values PCu1’, PCv1’, PCw1’ detected during the second time period, and determining the largest one among the phase current values PCu2, PCv2, PCw2 detected during the second time period and the phase current values PCu2’, PCv2’, PCw2’ detected during the second time period.

[0053] The turn-off self-check process 300 further includes, at block 370, determining whether the first associated disconnect PD1 is successfully turned off based on whether the largest one among PCu1, PCv1, PCw1 and PCu1’, PCv1’, PCw1’ reaches the current threshold A, and determining whether the second associated disconnect PD2 is successfully turned off based on whether the largest one among PCu2, PCv2, PCw2 and PCu2’, PCv2’, PCw2’ reaches the current threshold A.

[0054] If the largest one among PCu1, PCv1, PCw1 and PCu1’, PCv1’, PCw1’ reaches the current threshold A, it is determined that the first associated disconnect PD1 has a turn-off failure; otherwise, it is determined that the first associated disconnect PD1 is successfully turned off. Similarly, if the largest one among PCu2, PCv2, PCw2 and PCu2’, PCv2’, PCw2’ reaches the current threshold A, it is determined that the second associated disconnect PD2 has a turn-off failure; otherwise, it is determined that the second associated disconnect PD2 is successfully turned off. Thus, the turn-off self-check of the associated disconnect is completed.

[0055] In one embodiment, the current threshold A is set to at least twice the maximum value of the zero-drift current values of each phase of the first motor winding and the second motor winding. In another embodiment, the current threshold A is determined through a current threshold determination step. The current threshold determination step includes: when the first related breaker PD1 and the second related breaker PD2 are both closed, setting the three-phase duty ratios of the first motor winding and the second motor winding to 0.5 respectively, and then adjusting the three-phase duty ratios of the first motor winding and the second motor winding until the actual corresponding phase current increases to a level where it can be clearly determined that there is current; and determining the value of the actual corresponding phase current as the current threshold A.

[0056] Figure 4 FIG. shows a flowchart of the pull-in self-check process 400 of a related breaker according to an embodiment of the present disclosure.

[0057] When performing the pull-in self-check, the pull-in self-check is sequentially performed for each phase of the three phases of the first motor winding and the second motor winding respectively, and the phase currently being self-checked is the current target phase. It is respectively determined whether the current values of the current target phases of the first motor winding and the second motor winding are greater than the current threshold. If the current value of the current target phase is greater than the current threshold, the current target phase is successfully pulled in; otherwise, the current target phase has a pull-in failure.

[0058] The pull-in self-check process 400 starts at block 410. At block 410, the first related breaker driver chip PDD1 and the second related breaker driver chip PDD2 respectively send pull-in commands to the first related breaker PD1 and the second related breaker PD2.

[0059] The pull-in self-check process 400 includes, at block 420, the first MCU MCU1 sending first three-phase duty ratio commands DTu1, DTv1, DTw1 to the first gate driver GDU1, and at the same time the second MCU MCU2 sending second three-phase duty ratio commands DTu2, DTv2, DTw2 to the second gate driver GDU2. Among them, the first three-phase duty ratio commands DTu1, DTv1, DTw1 specify the duty ratios of the U phase, V phase, and W phase of the first motor winding, and the second three-phase duty ratio commands DTu2, DTv2, DTw2 specify the duty ratios of the U phase, V phase, and W phase of the second motor winding. And the sum of the duty ratios of each phase specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the corresponding phase specified in the second three-phase duty ratio commands DTu2, DTv2, DTw2 is 1.

[0060] The pull-in self-check process 400 then includes, in block 430, with phase U as the current target phase, during the third time period, in sub-block 431, setting the duty ratios of the U-phase, V-phase, and W-phase of the first motor winding specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 to x, 1 - x, 1 - x respectively, and setting the duty ratios of the U-phase, V-phase, and W-phase of the second motor winding specified in the second three-phase duty ratio commands DTu2, DTv2, DTw2 to 1 - x, x, x respectively, where 0.5 < x ≤ 0.6; in sub-block 432, causing the first gate driver GDU1 and the second gate driver GDU2 to drive the first bridge arm module B61 and the second bridge arm module B62 according to the duty ratios specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the second three-phase duty ratio commands DTu2, DTv2, DTw2 respectively; in sub-block 433, detecting the first set of phase current values PCu1, PCv1, PCw1 collected by the first phase current sampler S1 and the second set of phase current values PCu2, PCv2, PCw2 collected by the second phase current sampler S2 respectively; in sub-block 434, determining whether the U-phase of the first corrector PD1 is successfully pulled in based on whether the maximum value of PCu1 in the first set of phase current values PCu1, PCv1, PCw1 reaches the current threshold A, and determining whether the U-phase of the second corrector PD2 is successfully pulled in based on whether the maximum value of PCu2 in the second set of phase current values PCu2, PCv2, PCw2 reaches the current threshold A.

[0061] The current threshold A is the current value when, with both the first corrector PD1 and the second corrector PD2 pulled in, the duty ratios specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the second three-phase duty ratio commands DTu2, DTv2, DTw2 are adjusted so that the actual phase current increases to a value where it can be clearly determined whether there is current or not.

[0062] The suction self-check process 400 then includes, in block 440, with the V phase as the current target phase, during the fourth time period, in sub-block 441, adjusting the duty ratios of the U phase, V phase, and W phase of the first motor winding specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 to 1 - x, x, 1 - x respectively, and adjusting the duty ratios of the U phase, V phase, and W phase of the second motor winding specified in the second three-phase duty ratio commands DTu2, DTv2, DTw2 to x, 1 - x, x respectively, where 0.5 < x ≤ 0.6; in sub-block 442, causing the first gate driver GDU1 and the second gate driver GDU2 to drive the first leg module B61 and the second leg module B62 respectively according to the adjusted duty ratios specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the second three-phase duty ratio commands DTu2, DTv2, DTw2; in sub-block 443, detecting the first set of phase current values PCu1, PCv1, PCw1 collected by the first phase current sampler S1 and the second set of phase current values PCu2, PCv2, PCw2 collected by the second phase current sampler S2 respectively; in sub-block 444, determining whether the V phase of the first interrupter PD1 is successfully suctioned based on whether the maximum value of PCv1 in the first set of phase current values PCu1, PCv1, PCw1 reaches the current threshold A, and determining whether the V phase of the second interrupter PD2 is successfully suctioned based on whether the maximum value of PCv2 in the second set of phase current values PCu2, PCv2, PCw2 reaches the current threshold A.

[0063] The pull-in self-check process 400 then includes, in block 450, with the W phase as the current target phase, during five time periods, in sub-block 451, adjusting the duty ratios of the U, V, and W phases of the first motor winding specified in the first three-phase duty ratio commands DTu1, DTv1, and DTw1 to 1 - x, 1 - x, and x respectively, and adjusting the duty ratios of the U, V, and W phases of the second motor winding specified in the second three-phase duty ratio commands DTu2, DTv2, and DTw2 to x, x, and 1 - x respectively, where 0.5 < x ≤ 0.6; in sub-block 452, causing the first gate driver GDU1 and the second gate driver GDU2 to drive the first leg module B61 and the second leg module B62 according to the adjusted duty ratios specified in the first three-phase duty ratio commands DTu1, DTv1, DTw1 and the second three-phase duty ratio commands DTu2, DTv2, DTw2; in sub-block 453, detecting the first set of phase current values PCu1, PCv1, PCw1 collected by the first phase current sampler S1 and the second set of phase current values PCu2, PCv2, PCw2 collected by the second phase current sampler S2 respectively; in sub-block 454, determining whether the W phase of the first corrector PD1 has been successfully pulled in based on whether the maximum value of PCw1 in the first set of phase current values PCu1, PCv1, PCw1 reaches the current threshold A, and determining whether the W phase of the second corrector PD2 has been successfully pulled in based on whether the maximum value of PCw2 in the second set of phase current values PCu2, PCv2, PCw2 reaches the current threshold A.

[0064] During the third time period, if the maximum value of PCu1 reaches the current threshold A, the U phase of the first corrector PD1 is successfully pulled in, otherwise the U phase of the first corrector PD1 has a pull-in failure; if the maximum value of PCu2 reaches the current threshold A, the U phase of the second corrector PD2 is successfully pulled in, otherwise the U phase of the second corrector PD2 has a pull-in failure.

[0065] During the fourth time period, if the maximum value of PCv1 reaches the current threshold A, the V phase of the first corrector PD1 is successfully pulled in, otherwise the V phase of the first corrector PD1 has a pull-in failure; if the maximum value of PCv2 reaches the current threshold A, the V phase of the second corrector PD2 is successfully pulled in, otherwise the V phase of the second corrector PD2 has a pull-in failure.

[0066] During the fifth time period, if the maximum value of PCw1 reaches the current threshold A, the W phase of the first corrector PD1 is successfully pulled in, otherwise the W phase of the first corrector PD1 has a pull-in failure; if the maximum value of PCw2 reaches the current threshold A, the W phase of the second corrector PD2 is successfully pulled in, otherwise the W phase of the first corrector PD2 has a pull-in failure.

[0067] The above-mentioned third time period, fourth time period, and fifth time period are all in the range of 50 to 100 milliseconds (including the endpoint values).

[0068] If the U-phase, V-phase, and W-phase of the first associated breaker PD1 are all successfully energized, then the first associated breaker PD1 is successfully energized. If the U-phase, V-phase, and W-phase of the second associated breaker PD2 are all successfully energized, then the second associated breaker PD2 is successfully energized, thereby completing the energization self-check of the first associated breaker PD1 and the second associated breaker PD2.

[0069] In one embodiment, the current threshold A is set to at least twice the maximum value of the zero-drift current values of each phase of the first motor winding and the second motor winding. In another embodiment, the current threshold A is determined through a current threshold determination step. The current threshold determination step includes: when the first associated breaker PD1 and the second associated breaker PD2 are both closed, setting the three-phase duty ratios of the first motor winding and the second motor winding to 0.5 respectively, and then adjusting the three-phase duty ratios of the first motor winding and the second motor winding until the actual corresponding phase current increases to a level where it can be clearly determined that there is current; and determining the value of the actual corresponding phase current as the current threshold A.

[0070] It should be noted that in Figure 4 the energization self-check process 400 of the associated breaker, the energization self-check is sequentially performed on the U-phase, V-phase, and W-phase of the first motor winding and the second motor winding respectively. However, in other embodiments, the energization self-check can be performed in other orders, that is, the order of the U-phase, V-phase, and W-phase as the current target phase can be adjusted as needed and is not limited in this application.

[0071] According to the turn-off self-check process and the energization self-check process of the associated breaker of the embodiment of the present application, during the self-check, the voltage applied is used to output direct current by giving two sets of duty ratios to the motor, and then a disconnection command is sent to the associated breaker to check whether there is current flowing through the corresponding two sets of motor windings. For each phase of the motor winding, ensure that the sum of the duty ratios issued by the first MCU MCU1 and the second MCU MCU2 is 1, so that the two sets of motor windings generate currents with the same magnitude and opposite directions, and then generate torques with opposite directions to cancel each other out.

[0072] According to the turn-off self-check process and the energization self-check process of the associated breaker of the embodiment of the present application, the self-check of the associated breaker of the dual-redundant electric power steering system is realized while ensuring that the total output torque of the vehicle's motor is 0. In addition, when self-checking each set of associated breakers, two sets of duty ratios are alternately given, so that the current directions of two phases of the three-phase windings are changed successively, preventing omissions in the disconnection self-check of the associated breaker.

[0073] Figure 5FIG. 0 shows a schematic block diagram of an electronic device 500 used in a vehicle according to an embodiment of the present invention. As Figure 5 shown, in some embodiments, the electronic device 500 used in a vehicle may include a processor 502, a communication module 504, and a memory 506, which are electrically connected directly or indirectly between any two of them to achieve data transmission or interaction. For example, these components may be electrically connected to each other through one or more communication buses or signal lines. The processor 502 may include, but is not limited to, a general-purpose processor (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a network processor (NP), etc.), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The communication module 504 is used for wired or wireless communication with related devices outside the vehicle 500, and / or wired or wireless communication with other devices in the vehicle. The memory 506 may include, but is not limited to, a random access memory, a read-only memory, a programmable read-only memory, an erasable programmable read-only memory, an electrically erasable programmable read-only memory, etc., and may be used to store various programs for the processor 502 to execute and various intermediate variables and final results generated when the processor 502 processes the programs. For example, the memory 506 in the electronic device 500 may be used to store machine-readable instructions, which when executed by the processor 502, implement the Figures 2 to 4 turn-off self-checking process and pull-in self-checking process of the related breaker as

[0074] Understandable, Figure 5 the structure shown is only a schematic structural diagram of the electronic device 500, and the electronic device 500 may also include more or fewer components than Figure 5 shown. Figure 5 The various components shown may be implemented in hardware, software, or a combination thereof.

[0075] The present invention may be embodied in other specific forms without departing from its spirit and essential characteristics. For example, the algorithms described in specific embodiments may be modified without departing from the basic spirit of the present invention in terms of the system architecture. Therefore, the current embodiments are to be considered in all respects as illustrative and not restrictive, the scope of the present invention is defined by the appended claims rather than the above description, and all changes falling within the meaning and equivalents of the claims are thus included within the scope of the present invention.

Claims

1. A related breaker self-check control method, applicable to a dual-redundant electric power steering system in a vehicle. The dual-redundant electric power steering system includes a first motor winding and a second motor winding. The method includes: A collaborative control step of collaboratively controlling the first motor winding and the second motor winding so that the total output torque of the first motor winding and the second motor winding is 0; And A related breaker self-check step of controlling the related breakers of each phase of the first motor winding and the second motor winding to perform a related breaker self-check according to the current value of each phase.

2. The related breaker self-check control method according to claim 1, wherein, The collaborative control step includes: collaboratively setting the duty ratios of the first motor winding and the second motor winding so that the total output torque of the first motor winding and the second motor winding is 0.

3. The relevant breaker self-check control method according to claim 2, wherein, The related breaker self-check includes an off self-check and / or an on self-check. The related breaker self-check step includes: Simultaneously disconnecting / closing the related breakers of each phase of the first motor winding and the second motor winding; Collecting the current values of each phase of the first motor winding and the second motor winding; When performing the off self-check, for the first motor winding and the second motor winding, respectively determine whether the largest one of the current values of each phase is less than the current threshold. If the largest one is less than the current threshold, the disconnection is successful; otherwise, the disconnection fails. When performing the on self-check, sequentially perform an on self-check for each phase of the three phases of the first motor winding and the second motor winding respectively, and the phase currently being self-checked is the current target phase. Respectively determine whether the current value of the current target phase of the first motor winding and the second motor winding is greater than the current threshold. If the current value of the current target phase is greater than the current threshold, the current target phase is successfully closed; otherwise, the current target phase fails to close.

4. The relevant breaker self-check control method according to claim 3, wherein, When performing the off self-check, The collaborative control step includes: Driving the first motor winding and the second motor winding according to a first pair of three-phase duty ratios and maintaining for a first time period. The first pair of three-phase duty ratios makes the sum of the duty ratio of each phase of the first motor winding and the corresponding phase of the second motor winding equal to 1; and Driving the first motor winding and the second motor winding according to a second pair of three-phase duty ratios and maintaining for a second time period. The second pair of three-phase duty ratios is different from the first pair of three-phase duty ratios, but still makes the sum of the duty ratio of each phase of the first motor winding and the corresponding phase of the second motor winding equal to 1; The related breaker self-check step includes: During the first time period, respectively collecting the first set of current values of each phase of the first motor winding and the second motor winding; During the second time period, respectively collecting the second set of current values of each phase of the first motor winding and the second motor winding; and For the first motor winding and the second motor winding respectively, determining the maximum value among the first set of current values of each phase and the second set of current values of each phase as the largest one of the current values of each phase.

5. The related breaker self-check control method according to claim 4, wherein, The duty ratios for the three phases of the first motor winding in the first pair of three-phase duty ratios are x, 1 - x, 1 - x, and the duty ratios for the three phases of the first motor winding in the second pair of three-phase duty ratios are 1 - x, x, 1 - x, where 0.5 < x ≤ 0.

6.

6. The relevant breaker self-check control method according to claim 4, wherein, Both the first time period and the second time period are in the range of 50 to 100 milliseconds.

7. The related breaker self-check control method according to claim 3, wherein, When performing the self-check for suction, the collaborative control steps include: Collaboratively setting the duty ratios of the first motor winding and the second motor winding such that the duty ratio of the current target phase of the first motor winding is x, the duty ratios of the other two phases of the first motor winding are both 1 - x, and the duty ratio of the current target phase of the second motor winding is 1 - x, the duty ratios of the other two phases of the second motor winding are both x, where 0.5 < x ≤ 0.6; and Driving the first motor winding and the second motor winding according to the set duty ratios within a predetermined time period; The relevant breaker self-check steps include: During the predetermined time period, respectively collecting the current values of the current target phases of the first motor winding and the second motor winding.

8. The related breaker self-check control method according to claim 7, wherein, The predetermined time period is in the range of 50 to 100 milliseconds.

9. The relevant breaker self-check control method according to any one of claims 3 to 8, wherein, The current threshold is at least twice the maximum value of the zero-drift current values of each phase of the first motor winding and the second motor winding.

10. The related breaker self-check control method according to any one of claims 3 to 8 further includes: The current threshold determination step, which includes: Setting the three-phase duty ratios of both the first motor winding and the second motor winding to 0.5; Adjusting the three-phase duty ratios of the first motor winding and the second motor winding until the actual corresponding phase current increases to a level where it can be clearly determined that there is current; and Determining the value of the corresponding phase current as the current threshold.

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