Motor driving system, method of controlling motor driving system, and computer device

Abstract

The invention relates to a motor driving system, a method for controlling the motor driving system, computer equipment and a computer storage medium. The motor driving system according to one aspect of the present application comprises: an AC motor comprising a first phase motor winding, a second phase motor winding, and a third phase motor winding; an inverter power module coupled to the first phase motor winding via a first phase AC output line, to the second phase motor winding via a second phase AC output line, and to the third phase motor winding via a third phase AC output line; a first switching element coupled between the first phase AC output line and the second phase AC output line; and a second switching element coupled between the second phase AC output line and the third phase AC output line; wherein the first switching element and the second switching element are arranged to be in a normally open state and closed in response to a fault signal of the motor drive system.

Description

Technical Field

[0001] The present application generally relates to electric vehicle technology, and more particularly to a motor drive system, a method for controlling a motor drive system, a computer device for controlling a motor drive system, and a computer storage medium. Background Art

[0002] In electric vehicles, the normal operation of the motor drive system is extremely important. Once the motor drive system fails, it may cause damage to the device and even affect the vehicle's control. Currently, when the motor drive system fails, it needs to be controlled to enter a safe state, output zero torque or an acceptable safe braking torque to slowly stop the vehicle.

[0003] Generally speaking, the safety state can include the active short circuit (ASC) state of the motor at high speed and the three-phase free flow (also known as the safety pulse off (SPO)) state of the motor at low speed to ensure that the motor output is close to zero torque. In the ASC state, the power devices of the upper bridge arm or lower bridge arm of the three-phase full bridge of the motor are all turned on, and in the SPO state, the power devices of the upper bridge arm and lower bridge arm of the three-phase full bridge of the motor are all turned off.

[0004] However, the above ASC and SPO cannot guarantee the safe operation of the motor drive system. For example, the above ASC and SPO are both implemented by controlling the power device of the motor three-phase full bridge. When the power device fails, the ASC state and SPO state entered by controlling the power device are unreliable, and even cause the failure of the power device to further expand. Summary of the invention

[0005] In order to solve or at least alleviate one or more of the above problems, the following technical solutions are provided.

[0006] According to a first aspect of the present application, a motor drive system is provided, the motor drive system comprising: an AC motor, the AC motor comprising a first-phase motor winding, a second-phase motor winding and a third-phase motor winding; an inverter power module, the inverter power module is coupled to the first-phase motor winding via a first-phase AC output line, coupled to the second-phase motor winding via a second-phase AC output line and coupled to the third-phase motor winding via a third-phase AC output line; a first switching element, the first switching element is coupled between the first-phase AC output line and the second-phase AC output line; and a second switching element, the second switching element is coupled between the second-phase AC output line and the third-phase AC output line; wherein the first switching element and the second switching element are set to be in a normally open state and closed in response to a fault signal of the motor drive system.

[0007] According to the motor drive system described in an embodiment of the present application, the motor drive system further includes: a control unit configured to close the first switch element and the second switch element in response to a fault signal of the motor drive system.

[0008] According to the motor drive system of one embodiment of the present application or any one of the above embodiments, the fault signal is used to indicate that a power switch device in the inverter power module fails.

[0009] According to the motor drive system of one embodiment of the present application or any one of the above embodiments, the first switch element and the second switch element are normally open software triggered switches.

[0010] According to the motor drive system of one embodiment of the present application or any of the above embodiments, the inverter power module includes: a first-phase inverter bridge, the first-phase inverter bridge is coupled to the first-phase motor winding via the first-phase AC output line; a second-phase inverter bridge, the second-phase inverter bridge is coupled to the second-phase motor winding via the second-phase AC output line; and a third-phase inverter bridge, the third-phase inverter bridge is coupled to the third-phase motor winding via the third-phase AC output line.

[0011] According to the motor drive system described in one embodiment of the present application or any one of the above embodiments, when the first switching element and the second switching element are in the normally disconnected state, the first phase AC generated by the inverter power module is input to the first phase motor winding via the first phase AC output line, the second phase AC generated by the inverter power module is input to the second phase motor winding via the second phase AC output line, and the third phase AC generated by the inverter power module is input to the third phase motor winding via the third phase AC output line.

[0012] According to the motor drive system described in one embodiment of the present application or any one of the above embodiments, when the first switching element and the second switching element are in a closed state, the first phase motor winding, the first switching element and the second phase motor winding form a current loop, and the second phase motor winding, the second switching element and the third phase motor winding form a current loop.

[0013] According to the second aspect of the present application, a method for controlling the motor drive system according to the first aspect of the present application is provided, the method comprising: detecting a fault in the motor drive system; closing a first switch element and a second switch element in response to detecting a fault in the motor drive system; and maintaining the first switch element and the second switch element in a normally open state in response to not detecting a fault in the motor drive system.

[0014] According to a method for controlling a motor drive system according to an embodiment of the present application, the fault of the motor drive system includes a fault of a power switch device in an inverter power module.

[0015] In the method for controlling a motor drive system according to one embodiment of the present application or any one of the above embodiments, the first switch element and the second switch element are normally open software triggered switches.

[0016] According to the third aspect of the present application, a computer device for controlling a motor drive system is provided, the computer device comprising: a memory; a processor coupled to the memory; and a computer program stored on the memory and running on the processor, the running of the computer program resulting in the execution of the steps of the method for controlling a motor drive system according to the second aspect of the present application.

[0017] According to a fourth aspect of the present application, a computer storage medium is provided, wherein the computer storage medium comprises instructions, and the instructions, when run, execute the steps of the method for controlling a motor drive system according to the first aspect of the present application.

[0018] According to one or more embodiments of the present application, the motor drive system is provided with a first switch element coupled between the first phase AC output line and the second phase AC output line and a second switch element coupled between the second phase AC output line and the third phase AC output line, and the first switch element and the second switch element are set to be in a normally open state and closed in response to a fault signal of the motor drive system, so that when the motor drive system is working normally, the current loop does not pass through the first switch element and the second switch element, thereby ensuring that the first switch element and the second switch element do not affect the normal operation of the motor drive system, improving the vibration reliability of the inverter power module in the motor drive system, and forming a current loop between the motor winding and the first switch element and the second switch element when the motor drive system fails, thereby ensuring that the motor energy will not be transmitted to the motor drive system that has already failed and causing the fault to further expand, thereby improving the reliability and safety of the motor drive system. According to one or more embodiments of the present application, the motor drive system has the advantages of cost saving, simple control, and easy implementation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and / or other aspects and advantages of the present application will become clearer and easier to understand through the following description of various aspects in conjunction with the accompanying drawings, in which the same or similar units are represented by the same reference numerals. In the accompanying drawings:

[0020] Figure 1 A structural block diagram of a motor drive system according to one or more embodiments of the present application is shown.

[0021] Figure 2 A flow chart of a method for controlling a motor drive system according to one or more embodiments of the present application is shown.

[0022] Figure 3 A schematic block diagram of a computer device for controlling a motor drive system according to one or more embodiments of the present application is shown. DETAILED DESCRIPTION

[0023] The present application is described more fully below with reference to the accompanying drawings in which illustrative embodiments of the present application are illustrated. However, the present application may be implemented in different forms and should not be interpreted as being limited to the embodiments given herein. The above embodiments are given to make the disclosure herein comprehensive and complete, so as to more fully convey the scope of protection of the present application to those skilled in the art.

[0024] In the context of the present application, terms such as “comprise” and “include” mean that in addition to the units and steps directly and explicitly stated in the specification and claims, the technical solution of the present application does not exclude the situation where it has other units and steps that are not directly or explicitly stated.

[0025] In the context of the present application, unless otherwise specified, terms such as "first" and "second" do not indicate the order of units in terms of time, space, size, etc., but are merely used to distinguish between units.

[0026] In the context of the present application, “coupling” should be understood to include the situation where electric energy or electric signals are directly transmitted between two units, or the situation where electric energy or electric signals are indirectly transmitted via one or more intermediate units.

[0027] Hereinafter, various exemplary embodiments according to the present application will be described in detail with reference to the accompanying drawings.

[0028] Figure 1 A structural block diagram of a motor drive system according to one or more embodiments of the present application is shown.

[0029] like Figure 1 As shown in FIG. 1 , the motor drive system 100 includes an AC motor 110 , an inverter power module 120 , a first switching element S1 , and a second switching element S2 .

[0030] The AC motor 110 includes a first-phase motor winding, a second-phase motor winding, and a third-phase motor winding, for example Figure 1The A-phase motor winding LA, the B-phase motor winding LB and the C-phase motor winding LC are shown in FIG. The AC motor 110 is connected to the positive DC input DC+ and the negative DC input DC- through the inverter power module 120. The positive DC input DC+ and the negative DC input DC- are respectively connected to the positive end and the negative end of the bus capacitor C. Exemplarily, the positive DC input DC+ and the negative DC input DC- can be coupled to a high-voltage power battery.

[0031] The inverter power module 120 is coupled to the first phase motor winding via the first phase AC output line, coupled to the second phase motor winding via the second phase AC output line, and coupled to the third phase motor winding via the third phase AC output line. Figure 1 As shown in , the inverter power module 120 is coupled to the A-phase motor winding LA via the U-phase AC output line L1, to the B-phase motor winding LB via the V-phase AC output line L2, and to the C-phase motor winding LC via the W-phase AC output line L3.

[0032] Optionally, the inverter power module 120 may include a first-phase inverter bridge, a second-phase inverter bridge, and a third-phase inverter bridge, wherein the first-phase inverter bridge is coupled to the first-phase motor winding via the first-phase AC output line, the second-phase inverter bridge is coupled to the second-phase motor winding via the second-phase AC output line, and the third-phase inverter bridge is coupled to the third-phase motor winding via the third-phase AC output line. Figure 1 As shown in , the inverter power module 120 may include a U-phase inverter bridge (including power switching devices Q1 and Q2), a V-phase inverter bridge (including power switching devices Q3 and Q4), and a W-phase inverter bridge (including power switching devices Q5 and Q6), wherein the U-phase inverter bridge is coupled to the A-phase motor winding LA via the U-phase AC output line L1, the V-phase inverter bridge is coupled to the B-phase motor winding LB via the V-phase AC output line L2, and the W-phase inverter bridge is coupled to the C-phase motor winding LC via the W-phase AC output line L3. Exemplarily, the power switching devices Q1-Q6 may be implemented as an insulated gate bipolar transistor (IGBT), a metal oxide semiconductor field effect transistor (MOSFET), a bipolar junction transistor (BJT), a super junction transistor (SJT), etc.

[0033] The first switch element S1 is coupled between the first phase AC output line and the second phase AC output line, the second switch element S2 is coupled between the second phase AC output line and the third phase AC output line, and the first switch element S1 and the second switch element S2 are set to be in a normally open state and closed in response to a fault signal of the motor drive system 100. Figure 1 As shown in FIG. 1 , the first switch element S1 is coupled between the U-phase AC output line L1 and the V-phase AC output line L2, and the second switch element S2 is coupled between the V-phase AC output line L2 and the W-phase AC output line L3. Optionally, the fault signal of the motor drive system 100 can be used to indicate that a power switch device in the inverter power module 120 has a fault, for example, to indicate that Figure 1 One or more of the power switch devices Q1-Q6 shown in FIG. 1 fail, such as a short circuit failure, an open circuit failure, etc.

[0034] Optionally, the motor drive system 100 may include a control unit ( Figure 1 The control unit may be configured to close the first switch element S1 and the second switch element S2 in response to the fault signal of the motor drive system 100. For example, the control unit may be implemented as a motor control unit MCU. For example, the fault signal of the motor drive system 100 may be detected by a fault diagnosis device ( Figure 1 For example, the fault diagnosis device can monitor the three-phase current of the inverter power module 120 in real time and analyze the change of the current waveform to detect the open circuit and short circuit faults of the power switch devices Q1-Q6. For example, an open circuit fault may cause the current waveform to be distorted, while a short circuit fault may cause a sharp increase in current. By comparing the actual current with the current waveform during normal operation, the occurrence of the fault can be identified.

[0035] In one embodiment, the first switch element S1 and the second switch element S2 can be implemented as normally open software-triggered switches, which can be precisely controlled in response to a fault signal, for example, closed within a few milliseconds, so as to completely decouple the AC motor 110 from the inverter power module 120 by short-circuiting the A-phase motor winding LA, the B-phase motor winding LB, and the C-phase motor winding LC of the AC motor 110, thereby ensuring that the motor energy will not be transmitted to the inverter power module 120 that has already failed, thereby causing the fault to further expand. In one embodiment, the first switch element S1 and the second switch element S2 can be implemented as normally open Pyrofuse switches. When the power switch devices Q1-Q6 in the inverter power module 120 fail, the Pyrofuse switch can completely decouple the AC motor 110 from the inverter power module 120 in a timely manner, thereby achieving a rapid response to the fault and improving the reliability and safety of the motor drive system 100.

[0036] When the first switch element S1 and the second switch element S2 are in a normally disconnected state, the first phase AC generated by the inverter power module 120 is input to the first phase motor winding via the first phase AC output line, the second phase AC generated by the inverter power module 120 is input to the second phase motor winding via the second phase AC output line, and the third phase AC generated by the inverter power module 120 is input to the third phase motor winding via the third phase AC output line. Figure 1 As shown in , the U-phase AC generated by the inverter power module 120 is input to the A-phase motor winding LA via the U-phase AC output line L1, the V-phase AC generated by the inverter power module 120 is input to the B-phase motor winding LB via the V-phase AC output line L2, and the W-phase AC generated by the inverter power module 120 is input to the C-phase motor winding LC via the W-phase AC output line L3. Optionally, the U-phase AC, the V-phase AC, and the W-phase AC can be mutually shifted in sequence with a phase difference of 120°, and the U-phase AC, the V-phase AC, and the W-phase AC are respectively input to the A-phase motor winding LA, the B-phase motor winding LB, and the C-phase motor winding LC of the AC motor 110 to control the speed and torque of the AC motor 110. That is, when the motor drive system 100 is operating normally, the current loop does not pass through the first switch element S1 and the second switch element S2, thereby ensuring that the first switch element S1 and the second switch element S2 do not affect the normal operation of the motor drive system 100, such as not changing the DC busbar structure used to carry and transmit high-voltage current, and not affecting the working efficiency and vibration reliability of the inverter power module 120.

[0037] When the first switch element S1 and the second switch element S2 are in a closed state, that is, when a fault occurs in the motor drive system 100, the first phase motor winding, the first switch element S1 and the second phase motor winding form a current loop, and the second phase motor winding, the second switch element S2 and the third phase motor winding form a current loop. Figure 1 As shown in the figure, the A-phase motor winding LA, the first switching element S1 and the B-phase motor winding LB form a current loop, and the B-phase motor winding LB, the second switching element S2 and the C-phase motor winding LC form a current loop, thereby forming a local transfer of energy of the AC motor 110, ensuring that the motor energy will not be transmitted to the motor drive system 100 where a fault has already occurred, causing the fault to further expand, thereby improving the reliability and safety of the motor drive system.

[0038] In one embodiment, reference Figure 1As shown in , when a fault occurs in the motor drive system 100, by closing the first switch element S1 coupled between the U-phase AC output line L1 and the V-phase AC output line L2 and the second switch element S2 coupled between the V-phase AC output line L2 and the W-phase AC output line L3, the AC motor 110 can reliably enter a safe state, that is, a safe state in which the A-phase motor winding LA, the B-phase motor winding LB and the C-phase motor winding LC of the AC motor 110 are short-circuited by the first switch element S1 and the second switch element S2, avoiding the situation in which, when one or more of the power switching devices Q1-Q6 fail, the ASC state and the SPO state are entered by controlling the failed power switching devices, thereby further expanding the fault of the power device or failing to enter the ASC state and the SPO state.

[0039] According to one aspect of the present application, the motor drive system is provided with a first switch element coupled between the first phase AC output line and the second phase AC output line and a second switch element coupled between the second phase AC output line and the third phase AC output line, and the first switch element and the second switch element are set to be in a normally open state and closed in response to a fault signal of the motor drive system, so that when the motor drive system is working normally, the current loop does not pass through the first switch element and the second switch element, thereby ensuring that the first switch element and the second switch element do not affect the normal operation of the motor drive system, improving the vibration reliability of the inverter power module in the motor drive system, and forming a current loop between the motor winding and the first switch element and the second switch element when the motor drive system fails, thereby ensuring that the motor energy will not be transmitted to the motor drive system that has already failed and causing the fault to further expand, thereby improving the reliability and safety of the motor drive system. According to one aspect of the present application, the motor drive system has the advantages of cost saving, simple control, and easy implementation.

[0040] Figure 2 A flow chart of a method for controlling a motor drive system according to one or more embodiments of the present application is shown. Figure 2 The method shown in can be used to control Figure 1 The motor drive system 100 shown in FIG.

[0041] like Figure 2 As shown in FIG. 2 , in step S201 , a fault of the motor drive system is detected.

[0042] Optionally, in step S201, the fault of the motor drive system may include a fault of a power switch device in the inverter power module, such as a short circuit fault, an open circuit fault, etc. Exemplarily, the fault signal of the motor drive system may be generated by a fault diagnosis device of the motor drive system. For example, the fault diagnosis device may detect the open circuit and short circuit faults of the power switch device by monitoring the three-phase current of the inverter power module in real time and analyzing the changes in the current waveform. For example, an open circuit fault may cause the current waveform to be distorted, while a short circuit fault may cause a sharp increase in current. By comparing the actual current with the current waveform during normal operation, the occurrence of the fault may be identified. Optionally, in step S201, the fault of the motor drive system may be detected by determining whether a fault signal from the fault diagnosis device of the motor drive system is received.

[0043] In step S203, the first switch element and the second switch element are closed in response to detecting a fault in the motor drive system. When a fault occurs in the motor drive system, by closing the first switch element and the second switch element, the first-phase motor winding, the first switch element and the second-phase motor winding form a current loop, and the second-phase motor winding, the second switch element and the third-phase motor winding form a current loop, thereby forming a local transfer of energy of the AC motor, ensuring that the motor energy will not be transmitted to the motor drive system that has already failed, causing the fault to further expand, thereby improving the reliability and safety of the motor drive system.

[0044] In step S205, in response to not detecting a fault in the motor drive system, the first switch element and the second switch element are kept in a normally disconnected state. When no fault occurs in the motor drive system, by keeping the first switch element and the second switch element in a normally disconnected state, the first phase AC generated by the inverter power module is input to the first phase motor winding via the first phase AC output line, the second phase AC generated by the inverter power module is input to the second phase motor winding via the second phase AC output line, and the third phase AC generated by the inverter power module is input to the third phase motor winding via the third phase AC output line, so that the current loop does not pass through the first switch element and the second switch element, thereby ensuring that the first switch element and the second switch element do not affect the normal operation of the motor drive system, for example, the DC busbar structure for carrying and transmitting high voltage current is not changed, and the working efficiency and vibration reliability of the inverter power module are not affected.

[0045] Figure 3 A schematic block diagram of a computer device for controlling a motor drive system according to one or more embodiments of the present application is shown.

[0046] like Figure 3As shown in FIG. 1 , a computer device 300 for controlling a motor drive system includes a memory 310, a processor 320, and a computer program 330 stored in the memory 310 and executable on the processor 320. The processor 320 executes the computer program 330 to implement a method for controlling a motor drive system according to one aspect of the present application.

[0047] In addition, the present application may also be implemented as a computer storage medium in which a program for causing a computer to execute the method for controlling a motor drive system according to one aspect of the present application is stored.

[0048] Here, as computer storage media, various forms of computer storage media can be used, such as disks (for example, magnetic disks, optical disks, etc.), cards (for example, memory cards, optical cards, etc.), semiconductor memories (for example, ROMs, non-volatile memories, etc.), and tapes (for example, magnetic tapes, cassettes, etc.).

[0049] In the applicable situation, hardware, software or a combination of hardware and software can be used to realize the various embodiments provided by the application. Moreover, in the applicable situation, without departing from the scope of the application, the various hardware components and / or software components set forth herein can be combined into a composite component comprising software, hardware and / or both. In the applicable situation, without departing from the scope of the application, the various hardware components and / or software components set forth herein can be divided into subcomponents comprising software, hardware or both. In addition, in the applicable situation, it is contemplated that the software component can be implemented as a hardware component, and vice versa.

[0050] Software (such as program code and / or data) according to the present application can be stored on one or more computer storage media. It is also contemplated that the software identified herein can be implemented using one or more general or special-purpose computers and / or computer systems, networked and / or otherwise. Where applicable, the order of the various steps described herein can be changed, combined into composite steps, and / or divided into sub-steps to provide the features described herein.

[0051] The embodiments and examples set forth herein are provided to best illustrate embodiments according to the present application and its specific applications, and thereby enable those skilled in the art to implement and use the present application. However, those skilled in the art will appreciate that the above description and examples are provided only for ease of illustration and example. The description set forth is not intended to cover all aspects of the present application or to limit the present application to the precise form disclosed.

Claims

1. A motor drive system, characterized in that: The motor drive system comprises: An AC motor, the AC motor comprising a first-phase motor winding, a second-phase motor winding and a third-phase motor winding; an inverter power module, the inverter power module being coupled to the first phase motor winding via a first phase AC output line, coupled to the second phase motor winding via a second phase AC output line, and coupled to the third phase motor winding via a third phase AC output line; a first switching element coupled between the first-phase AC output line and the second-phase AC output line; and a second switch element, the second switch element being coupled between the second-phase AC output line and the third-phase AC output line; The first switching element and the second switching element are configured to be in a normally open state and to be closed in response to a fault signal of the motor drive system.

2. The motor drive system according to claim 1, wherein the motor drive system further comprises: A control unit is configured to close the first switching element and the second switching element in response to a fault signal of the motor drive system. 3 . The motor drive system according to claim 1 , wherein the fault signal is used to indicate that a power switch device in the inverter power module fails. 4 . The motor drive system according to claim 1 , wherein the first switch element and the second switch element are normally open software-triggered switches.

5. The motor drive system according to claim 1, wherein the inverter power module comprises: a first-phase inverter bridge coupled to the first-phase motor winding via the first-phase AC output line; a second-phase inverter bridge, the second-phase inverter bridge being coupled to the second-phase motor winding via the second-phase AC output line; as well as A third-phase inverter bridge is coupled to the third-phase motor winding via the third-phase AC output line.

6. The motor drive system according to claim 1, wherein when the first switching element and the second switching element are in the normally-off state, the first-phase AC generated by the inverter power module is input to the first-phase motor winding via the first-phase AC output line, the second-phase AC generated by the inverter power module is input to the second-phase motor winding via the second-phase AC output line, and the third-phase AC generated by the inverter power module is input to the third-phase motor winding via the third-phase AC output line.

7. The motor drive system according to claim 1, wherein when the first switching element and the second switching element are in a closed state, the first phase motor winding, the first switching element and the second phase motor winding form a current loop, and the second phase motor winding, the second switching element and the third phase motor winding form a current loop.

8. A method for controlling a motor drive system, characterized in that: The motor drive system is a motor drive system according to any one of claims 1 to 7, and the method comprises: detecting a fault in the motor drive system; closing the first switching element and the second switching element in response to detecting a fault in the motor drive system; and The first switching element and the second switching element are maintained in a normally-off state in response to no failure of the motor drive system being detected. 9 . The method for controlling a motor drive system according to claim 8 , wherein the fault of the motor drive system comprises a fault of a power switch device in an inverter power module. 10 . The method for controlling a motor drive system according to claim 8 , wherein the first switch element and the second switch element are normally open software-triggered switches.

11. A computer device for controlling a motor drive system, characterized in that: The computer device comprises: Memory; a processor coupled to the memory; and A computer program stored on the memory and running on the processor, the running of the computer program causing the method for controlling a motor drive system according to any one of claims 8 to 10 to be performed.

12. A computer storage medium, characterized in that: The computer storage medium includes instructions that, when executed, perform the method for controlling a motor drive system according to any one of claims 8 to 10.

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