CN115833659A - Safety protection device and operation method thereof, and BSG system - Google Patents
Safety protection device and operation method thereof, and BSG system Download PDFInfo
- Publication number
- CN115833659A CN115833659A CN202211575103.1A CN202211575103A CN115833659A CN 115833659 A CN115833659 A CN 115833659A CN 202211575103 A CN202211575103 A CN 202211575103A CN 115833659 A CN115833659 A CN 115833659A
- Authority
- CN
- China
- Prior art keywords
- bridge circuit
- gate driver
- state
- control module
- fault
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000000034 method Methods 0.000 title claims abstract description 12
- 230000001360 synchronised effect Effects 0.000 claims description 5
- 238000012545 processing Methods 0.000 description 5
- 230000001960 triggered effect Effects 0.000 description 3
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000011017 operating method Methods 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- 239000007858 starting material Substances 0.000 description 1
Images
Landscapes
- Control Of Electric Motors In General (AREA)
Abstract
The invention relates to a safety protection device for an electric machine, comprising: a gate driver for recognizing a failure of the motor control board and driving the bridge circuit if the failure is not recognized, the gate driver including a register and a failure output pin; a hardware circuit configured to turn off the gate driver when a fault signal is received from a fault output pin of the gate driver; and a software control module which is configured to read the operation condition of each switch tube in the bridge circuit from the register of the grid driver when receiving the fault signal, and confirm whether the switch tube in the bridge circuit is failed or not based on the reading result, so as to enable the bridge circuit to enter a corresponding safety protection state in a software control mode. The invention also relates to a BSG system comprising the safety protection device and an operation method of the safety protection device.
Description
Technical Field
The present invention relates to the field of electric machines, and more particularly, to a safety protection apparatus for an electric machine, a BSG system including the apparatus, and an operating method of the safety protection apparatus.
Background
With the development of new energy technology, the traditional fuel vehicle is gradually replaced by a new energy vehicle. In new energy vehicles, the electric machine is an important component that can power the vehicle. For example, in a hybrid vehicle, a common electrically excited Synchronous machine or Permanent Magnet Synchronous Machine (PMSM) may be used to power the vehicle. Specifically, in a BSG (Belt-Driven Starter Generator) system, a PMSM motor may be connected to an engine at the front end of the engine with a Belt drive mechanism instead of the original Generator to power the vehicle in an integrated manner.
For a PMSM motor, the operation of the motor is usually controlled by controlling a bridge circuit connected to the motor by means of a Gate Driver Unit (GDU). During operation of the motor, the switching tubes (e.g., MOSFETs) in its bridge circuit may fail.
In the existing motor safety protection scheme, failure faults of a switching tube in a bridge circuit are mostly processed according to a general fault processing mechanism, and an independent safety processing mechanism specially aiming at the failure of the switching tube is lacked.
Disclosure of Invention
In view of the above, according to a first aspect of the present invention, a safety protection device for an electric motor is provided, the electric motor being controlled by a motor control board, the motor control board comprising a bridge circuit formed by a low-side switching tube and a high-side switching tube, the safety protection device comprising, according to an alternative embodiment:
a gate driver configured to recognize a failure of the motor control board and drive the bridge circuit if no failure is recognized, the gate driver including a register in which operating conditions of respective switching tubes of the bridge circuit are stored and a failure output pin, wherein the gate driver is further configured to output a corresponding failure signal via the failure output pin when a failure of the motor control board is recognized;
hardware circuitry configured to turn off the gate driver when a fault signal is received from a fault output pin of the gate driver and to force the bridge circuitry into a freewheeling state in a hardware controlled manner; and
a software control module configured to read the operating condition of each switching tube in the bridge circuit from a register of the gate driver when a fault signal is received from a fault output pin of the gate driver, and confirm whether a switching tube failure occurs in the bridge circuit based on the read result, so as to enable the bridge circuit to enter a corresponding safety protection state in a software control mode.
According to an alternative embodiment, the software control module is further configured to disable the bridge circuit from entering the ASC state when a fault signal is received.
According to an alternative embodiment, the software control module is further configured to maintain the bridge circuit in a freewheeling state and to maintain the bridge circuit inhibited from entering the ASC state in the event of a switch tube failure in the bridge circuit.
According to an alternative embodiment, the software control module is further configured to issue a reset signal to the hardware circuit and to release the state control of the bridge circuit in case no switching tube failure occurs in the bridge circuit.
According to an alternative embodiment, the software control module is further configured to obtain a motor speed in case no switching tube failure occurs in the bridge circuit, and to control the bridge circuit to enter a corresponding safety protection state based on the obtained motor speed.
According to an alternative embodiment, the software control module is further configured to cause the bridge circuit to enter the ASC state if the motor speed is greater than a predetermined threshold.
According to an alternative embodiment, the software control module is further configured to cause the bridge circuit to enter a freewheeling state if the motor speed is less than or equal to a predetermined threshold.
According to a second aspect of the present invention, there is also provided a BSG system, including: a BSG and a motor control board including a safety protection device as described above.
According to an alternative embodiment, the electric machine is a permanent magnet synchronous machine.
According to a third aspect of the present invention, there is also provided a method of operating a safety protection device as described above, wherein the method of operating comprises the steps of:
identifying a fault of the motor control board by means of the gate driver, wherein, when a fault of the motor control board is identified:
turning off the gate driver by means of the hardware circuit and forcing the bridge circuit into a freewheeling state in a hardware-controlled manner;
reading the operating conditions of each switch tube of the bridge circuit from a register of the grid driver by means of the software control module, and confirming whether the switch tube failure occurs in the bridge circuit or not based on the reading result; and
the bridge circuit is brought into a corresponding safety protection state in a software-controlled manner by means of the software control module.
Drawings
Other features and advantages of the method of the present invention will be apparent from, or are more particularly, described in the accompanying drawings, which are incorporated herein, and the following detailed description of the invention, which together serve to explain certain principles of the invention.
Fig. 1 shows a schematic structural view of a safety protection device for an electric machine according to an exemplary embodiment of the present invention.
Fig. 2 shows a flow chart of the individual steps of the method of operation of the safety device for an electric machine shown in fig. 1.
Detailed Description
A safety protection device for an electric machine according to the present invention will be described below by way of embodiments with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention to those skilled in the art. It will be apparent, however, to one skilled in the art that the present invention may be practiced without some of these specific details. Rather, it is contemplated that the invention may be practiced with any combination of the following features and elements, whether or not they relate to different embodiments. Thus, the following aspects, features, embodiments and advantages are merely illustrative and should not be considered elements or limitations of the claims.
The applicant has found that in the event of a motor failure (e.g. a switch tube failure in a motor bridge circuit), it is necessary to implement active protection measures for the motor to avoid the motor continuing to output torque in the event of a failure. Among the two most common Active motor protection measures are freewheelling (also called Safety Pulse Off, abbreviated as "SPO") and ASC (Active Short Circuit, abbreviated as "ASC"). Freewhile is implemented by fully opening the switching tubes of the bridge circuit, and ASC is implemented by shorting all the low-side switching tubes (or all the high-side switching tubes) of the bridge circuit.
In the existing motor safety protection scheme, the GDU monitors the working condition of a motor control panel in real time, and reports the fault after identifying that a switching tube fails. After the software control module identifies the fault by reading the GDU register, the switching tube of the bridge circuit is triggered to be fully opened according to the common fault processing logic, so that the motor enters a Freewheelling state; or the low-side switch tube of the bridge circuit is triggered to be short-circuited, so that the motor enters an ASC state.
In this fault handling scheme for a switching tube failure, the link that puts the motor into a safe state is too long. Before the motor finally enters a safe state, an uncontrollable state of about 10ms exists, and under a specific working condition, the upper switching tube and the lower switching tube of a single bridge circuit in a bridge circuit are all conducted, so that the short circuit of a motor control board is caused, and secondary failure and high-voltage safety risk of the system are caused.
In order to reduce the secondary failure and high-voltage safety risk of a motor control board caused by the overlong response time of the motor entering a safety state, the invention provides a safety protection device for a motor (such as PMSM), which formulates a safety strategy in a mode of combining hardware and software when a circuit fails so as to enable the motor to enter a corresponding safety protection state. Specifically, in terms of hardware, a separate hardware circuit is added at the input end of the GDU, and a pin used by the GDU for reporting a fault is directly connected to a safety state trigger pin of the GDU through the hardware circuit, so that the bridge circuit is directly triggered to enter a freelifting safety state when the GDU reports the fault. In terms of software, when a switching tube failure is detected, the software control module, in addition to a normal fault recording, also simultaneously inhibits the software triggering of further safety states (in particular ASC states) of the electric machine.
Before describing the detailed structure of the safety protection device of the present invention, it must be noted that in this context, "software protection/protection provided in a software controlled manner" is to be understood as: the software control module outputs corresponding control signals to the bridge circuit after executing the steps of signal acquisition, processing, logic judgment and the like, so that the on-off of each switching tube in the bridge circuit is controlled, and therefore the protection measures for the motor are realized. "hardware protection/protection provided in a hardware-controlled manner" is to be understood as: the hardware circuit independent of the software control module is used for executing operations such as information acquisition, filtering processing, threshold value comparison and the like, and finally, physical electric signals are directly output to the bridge circuit, so that the on-off of each switching tube in the bridge circuit is controlled.
Fig. 1 shows a schematic structural diagram of a safety protection device for an electric machine M according to an exemplary embodiment of the present invention. The electric machine M may be, for example, a Permanent Magnet Synchronous machine M (PMSM), which is applicable to a BSG system of a hybrid vehicle. The specific structure of the safety protection device of the present invention is described in detail below with reference to a BSG system employing a PMSM motor solution.
As shown in fig. 1, the motor M can be driven by a motor control board that includes two sets of three-phase bridge circuits H, each set of bridge circuits H can be composed of three low-side switching transistors and three high-side switching transistors, and each switching transistor can be composed of a MOSFET.
As shown in fig. 1, the safety protection device may further include a Gate Driver Unit (GDU) 10, where the Gate Driver 10 may be connected to the Gate control terminal of each switching tube in the bridge circuit H. The gate driver 10 may recognize a failure of the motor control board and drive the bridge circuit H in the case where the failure is not recognized.
The gate driver 10 may include a register 101 and a fault output pin (not shown in fig. 1), and the operating conditions of each switching tube of the bridge circuit H, for example, the switching state and fault information of each switching tube, etc., are stored in the register 101. Wherein, the gate driver 10 is further configured to output a corresponding fault signal via the fault output pin when the motor control board is recognized to be faulty.
The safety protection device according to the present embodiment is characterized in that it further includes a hardware circuit 20, and the hardware circuit 20 is connectable to the fail output pin of the gate driver 10. When a fault signal is received from a fault output pin of the gate driver 10, the hardware circuit 20 may trigger the gate driver 10 to be turned off and force the bridge circuit H into a freewheeling state in a hardware controlled manner. For example, hardware circuit 20 may connect the failure pin of the GDU directly to a safe state trigger pin (not shown in fig. 1) of the GDU to directly trigger the freewheeling state of the circuit in the event of a failure.
In addition, the safety protection apparatus according to the present embodiment may further include a software control module 30, and the software control module 30 may be connected to a fault output pin of the gate driver 10, for example, via an SPI (serial peripheral interface) to receive a fault signal therefrom.
After receiving a fault signal regarding the motor control board (from the fault output pin of the gate driver 10), the software control module 30 may read the operating conditions of the respective switching tubes of the bridge circuit H from the register 101 of the gate driver 10, and confirm whether a switching tube failure occurs in the bridge circuit H based on the state reading result, thereby bringing the bridge circuit H into a corresponding safety protection state in a software-controlled manner. As an alternative example, the software control module 30 may also inhibit the bridge circuit from entering other safety states, in particular the ASC state, in a software-controlled manner when a fault signal is received.
Specifically, in the event of a switch tube failure in bridge circuit H, for example, a failure of one of the high side switch tubes in bridge circuit H, software control module 30 maintains bridge circuit H in a freewheeling state and maintains bridge circuit H inhibited from entering other safe states, particularly inhibited from entering the ASC state, until the drive cycle is updated.
If no switch tube failure occurs in the bridge circuit H, indicating that the fault signal output by the gate driver 10 is not related to the switch tube failure, the software control module 30 may send a reset signal to the hardware circuit 20 to release the state control of the bridge circuit H. The releasing may specifically include: the freewheeling state that the hardware circuit 20 forces the bridge circuit H into is released, and the software control module 30 is released from restricting the bridge circuit H from entering the ASC state.
According to an alternative example, in case that no switching tube failure occurs in the bridge circuit H, the software control module 30 may also read the rotation-variation-related signal and calculate the current motor speed, and control the bridge circuit H to enter the corresponding safety protection state based on the calculated motor speed. For example, when the motor speed is greater than a predetermined threshold value, the bridge circuit H (particularly the low-side switching tube thereof) is brought into the ASC state. When the motor speed is less than or equal to a predetermined threshold value, the bridge circuit H is brought into a freewheeling state.
The predetermined threshold may be set artificially based on a parameter of the motor, for example, the predetermined threshold may be set to a motor rotation speed at which a back electromotive voltage of the motor corresponds to a minimum usage voltage value (for example, 36V) of the battery pack.
Fig. 2 shows a flow chart of the individual steps of the method of operation of the safety device for an electric machine shown in fig. 1. The operation of the safety device is described in detail below with reference to fig. 2.
Firstly, a fault of the motor control board (for example, a switching tube fault in the motor drive inverter) is identified by means of the GDU, wherein, when a fault of the motor control board is identified, the GDU is turned off by means of a hardware circuit, and the bridge circuit is forced into a freewheeling state in a hardware-controlled manner. At the same time, as an alternative example, the bridge circuit can also be inhibited in a software-controlled manner by means of the software control module from entering other safety states, for example, the ASC state is prevented by the bridge circuit upon recognition of further faults of the motor control board.
Furthermore, when a fault of the motor control board is detected, the software control module reads the operating conditions of the individual switching tubes of the bridge circuit from the registers of the GDU and, on the basis of the reading, determines whether a switching tube failure has occurred in the bridge circuit.
Subsequently, the bridge circuit is brought into a corresponding safety protection state (e.g., freelifting state or ASC state) in a software-controlled manner by means of a software control module, depending on whether a switching tube failure has occurred in the bridge circuit.
In particular, in the event of a switching tube failure in the bridge circuit, the bridge circuit is kept in the freewetting state by means of the software control module, while the bridge circuit H is kept inhibited from entering other safe states, in particular from entering the ASC state, until the driving cycle is updated.
If a switch tube failure does not occur in the bridge circuit, indicating that the fault signal output by the gate driver 10 is not related to the switch tube failure, a reset signal may be sent to the hardware circuit by the software control module to release the state control of the bridge circuit (i.e., release the forced freeweling state and release the prohibition of the ASC state).
Optionally, when the switching tube fails, the software control module may acquire the motor speed and control the bridge circuit to enter the corresponding safety protection state based on the motor speed. For example, the software control module may spin the relevant signal from the upper controller via the SPI bus and calculate the current motor speed based on the spin-related signal, and it is understood that the motor speed is not limited to being obtained by the method listed herein, but may be obtained by other methods, such as by a speed sensor, and these variations are within the scope of the present invention. When the rotating speed of the motor is larger than a preset threshold value, the bridge circuit (especially the low-side switch tube thereof) can be put into an ASC state; in the case where the motor speed is less than or equal to the predetermined threshold value, the bridge circuit may be brought into a freewetting state.
The safety protection device according to the invention can significantly reduce the uncontrollable time of the bridge circuit before the motor enters the safe state-for example, the uncontrollable time from the identification of a system fault (e.g., a switching tube failure fault) to the bringing of the motor into the safe state can be reduced from 10ms in the conventional scheme to 5us, thereby reducing the risk of secondary failure of the bridge circuit and the safety risk of high circuit voltage.
It will be appreciated by the person skilled in the art that the individual steps of the method according to the invention are not limited to being carried out in the order listed above. In addition, in the present invention, the terms "comprising" and "including" mean that, in addition to having steps directly and explicitly stated in the specification and claims, the technical solutions of the present application do not exclude the case of having other steps not directly or explicitly stated.
Although the present invention has been described with reference to the preferred embodiments, it is not to be limited thereto. Various changes and modifications within the spirit and scope of the present invention will become apparent to those skilled in the art from this disclosure, and it is intended that the scope of the present invention be defined by the appended claims.
Claims (10)
1. A safety arrangement for an electric machine (M), characterized in that the electric machine is controlled by a machine control board comprising a bridge circuit (H) consisting of a low-side switching tube and a high-side switching tube, the safety arrangement comprising:
a gate driver (10), the gate driver (10) being configured to identify a fault of the motor control board and to drive the bridge circuit (H) if no fault is identified, the gate driver (10) comprising a register (101) in which operating conditions of the individual switching tubes of the bridge circuit (H) are stored and a fault output pin, wherein the gate driver (10) is further configured to output a corresponding fault signal via the fault output pin upon identification of a fault of the motor control board;
a hardware circuit (20), the hardware circuit (20) being configured to shut down the gate driver (10) when a fault signal is received from a fault output pin of the gate driver (10), and to force the bridge circuit (H) into a freewheeling state in a hardware controlled manner; and
a software control module (30), wherein the software control module (30) is configured to read the operation condition of each switch tube in the bridge circuit (H) from a register (101) of the gate driver (10) when a fault signal is received from a fault output pin of the gate driver (10), and confirm whether the switch tube failure occurs in the bridge circuit (H) or not based on the reading result, so that the bridge circuit (H) is brought into a corresponding safety protection state in a software control mode.
2. Safety arrangement according to claim 1, characterized in that the software control module (30) is further configured to inhibit the bridge circuit (H) from entering the ASC state when a fault signal is received.
3. The safety arrangement according to claim 2, characterized in that the software control module (30) is further configured to keep the bridge circuit (H) in a freewheeling state and to keep the bridge circuit (H) inhibited from entering an ASC state in case of a switching tube failure in the bridge circuit (H).
4. A safety arrangement according to any one of claims 1 to 3, wherein the software control module (30) is further configured to issue a reset signal to the hardware circuit (20) in the event of no switching tube failure in the bridge circuit (H) and to release the state control of the bridge circuit (H).
5. Safety arrangement according to claim 4, characterized in that the software control module (30) is further configured to acquire a motor speed in case no switching tube failure occurs in the bridge circuit (H) and to control the bridge circuit (H) into the respective safety state based on the acquired motor speed.
6. Safety protection device according to claim 5, characterized in that said software control module (30) is further configured to bring said bridge circuit (H) into an ASC state in the event of a motor speed greater than a predetermined threshold value.
7. A safety arrangement according to claim 5 or 6, wherein the software control module (30) is further configured to bring the bridge circuit (H) into a freewheeling state if the motor speed is less than or equal to a predetermined threshold value.
8. A BSG system, comprising:
an electric machine, and
a motor control board comprising the safety protection device according to any one of claims 1 to 7.
9. The BSG system of claim 8, wherein the electric machine is a permanent magnet synchronous machine.
10. Method of operating a safety arrangement according to any of claims 1 to 7, characterized in that it comprises the following steps:
-identifying a failure of the motor control board by means of the gate driver (10), wherein, when a failure of the motor control board is identified:
-turning off the gate driver (10) by means of the hardware circuit (20) and forcing the bridge circuit (H) into a freewheeling state in a hardware controlled manner;
-reading, by means of the software control module (30), the operating conditions of the individual switching tubes of the bridge circuit (H) from a register of the gate driver (10) and confirming, on the basis of the reading, whether a switching tube failure occurs in the bridge circuit (H); and
-bringing the bridge circuit (H) into a respective safety protection state in a software-controlled manner by means of the software control module (30).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211575103.1A CN115833659A (en) | 2022-12-08 | 2022-12-08 | Safety protection device and operation method thereof, and BSG system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211575103.1A CN115833659A (en) | 2022-12-08 | 2022-12-08 | Safety protection device and operation method thereof, and BSG system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115833659A true CN115833659A (en) | 2023-03-21 |
Family
ID=85545501
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211575103.1A Pending CN115833659A (en) | 2022-12-08 | 2022-12-08 | Safety protection device and operation method thereof, and BSG system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115833659A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024260759A1 (en) * | 2023-06-22 | 2024-12-26 | Robert Bosch Gmbh | Power electronics system for operating an electric machine, electric drive unit, and method for operating an electric power electronics system |
-
2022
- 2022-12-08 CN CN202211575103.1A patent/CN115833659A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2024260759A1 (en) * | 2023-06-22 | 2024-12-26 | Robert Bosch Gmbh | Power electronics system for operating an electric machine, electric drive unit, and method for operating an electric power electronics system |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN111106788B (en) | Active short-circuit protection system of motor | |
| CN110768213B (en) | Control circuit and control method for three-phase active short circuit of electric vehicle motor system | |
| CN108493904B (en) | IGBT safety turn-off system and method for turning off vehicle motor | |
| CN210898512U (en) | Three-phase active short-circuit control circuit of electric vehicle motor system | |
| US20100213904A1 (en) | Vehicle and discharge method of smoothing capacitor in vehicle | |
| CN110829949A (en) | Electric drive system fault protection method and device, vehicle and storage medium | |
| CN114285001B (en) | Vehicle motor control system and method | |
| US11431275B2 (en) | Motor control system having redundant electric control unit | |
| CN114527399A (en) | Method and system for safely designing an alternating current battery | |
| CN112858896B (en) | Flexible direct current converter valve power module bypass switch false switching-on test method and device | |
| CN115833659A (en) | Safety protection device and operation method thereof, and BSG system | |
| CN212304728U (en) | A control device of a drive circuit and an automobile power distribution system | |
| CN111762024B (en) | In-vehicle control device and recording medium | |
| US12068677B2 (en) | Drive circuit for power converter | |
| EP3839539A1 (en) | Method, system and apparatus for diagnosing malfunction in a power distribution unit | |
| CN113625696B (en) | Safety processing method and system for overcurrent protection of vehicle-mounted controller | |
| CN109334756A (en) | A kind of power-assisted steering double drive control system and its control method | |
| US12107571B2 (en) | Control circuit for power conversion apparatus | |
| CN218771277U (en) | Active short-circuit protection circuit of motor | |
| CN115683660B (en) | Driving diagnosis processing method and device for switching driving states in automobile electronics | |
| CN117681661A (en) | Motor safety protection device and electric drive system comprising same | |
| CN106707159A (en) | BLDC (brushless direct current) motor fault diagnosis system | |
| CN114670632B (en) | Fault processing method, device, equipment and automobile | |
| CN112019129B (en) | Drive protection method, bridge type drive system and motor controller | |
| JP2006304408A (en) | Power supply device and control method of power supply device |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |