Motor torque monitoring device and method, including a high-voltage inverter

Abstract

The present application relates to a kind of motor torque monitoring device, comprising: input port;First sampling channel and second sampling channel;First torque estimation unit is configured to determine the first torque estimation value of motor;First calculation unit is configured to calculate the first difference between first torque estimation value and torque request value;Second torque estimation unit is configured to determine the second torque estimation value of motor;Second calculation unit is configured to calculate the second difference between second torque estimation value and first torque estimation value;And control unit is further configured to send torque abnormal fault alarm and control motor enters safe protection state in the case where any of the following conditions is met: first difference exceeds first tolerance range;And second difference exceeds second tolerance range.The present application also relates to a kind of motor torque monitoring method, and high-voltage inverter comprising the device.

Description

Technical Field

[0001] This invention relates to the field of vehicle motors, and more specifically, to a motor torque monitoring device and a corresponding motor torque monitoring method, as well as a high-voltage inverter including the device. Background Technology

[0002] With the rapid development of new energy vehicles (such as electric vehicles), the high-voltage inverter, as a core component of the electric vehicle drive system, is playing an increasingly important role. The performance of the high-voltage inverter directly determines the overall performance of the motor. Therefore, how to maximize the performance of the high-voltage inverter has become a core issue that electric vehicle manufacturers urgently need to address.

[0003] During the operation of electric vehicles, the core of motor control lies in ensuring the accuracy of motor torque output. Therefore, the actual output torque of the motor is usually used as an important indicator for judging vehicle driving safety. However, under certain circumstances, due to hardware and software problems in the high-voltage inverter, electromagnetic interference, human error, etc., abnormal motor torque output may occur, which can pose a very serious safety hazard to vehicle operation.

[0004] In existing high-voltage inverters, it is difficult to identify abnormal torque output in the motor in a timely and accurate manner, which poses a significant safety hazard to vehicle operation. Summary of the Invention

[0005] In view of this, according to a first aspect of the present invention, a motor torque monitoring device is provided, the device comprising:

[0006] An input port is used to receive a torque request value from the motor from the vehicle's CAN bus;

[0007] The first sampling channel and the second sampling channel are respectively used to obtain the first operating parameter and the second operating parameter of the motor from at least one sensor;

[0008] A first torque estimation unit is configured to determine a first torque estimation value of the motor based on the first operating parameters and the motor design parameters.

[0009] A first calculation unit is configured to calculate a first difference between the first torque estimate and the torque request value;

[0010] The second torque estimation unit is configured to determine a second torque estimation value of the motor based on the second operating parameters;

[0011] A second calculation unit is configured to calculate a second difference between the second torque estimate and the first torque estimate; and

[0012] The control unit is configured to determine whether the first difference and the second difference fall within the corresponding tolerance range, wherein the control unit is further configured to send a torque abnormality fault alarm and control the motor to enter a safety protection state when any of the following conditions are met:

[0013] The first difference between the first estimated torque value and the requested torque value exceeds the first tolerance range; and

[0014] The second difference between the second torque estimate and the first torque estimate exceeds the second tolerance range.

[0015] Advantageously, the motor design parameters include the number of motor pole pairs, the first operating parameters include at least one of the motor's three-phase current, rotor position signal, and rotor temperature, and the second operating parameters include at least one of the motor's three-phase current, motor speed, bus voltage, stator temperature, and the duty cycle of the PWM control signal of the motor inverter.

[0016] Advantageously, the first torque estimation unit is configured to determine the rotor flux linkage value based on the three-phase current and the rotor temperature according to a pre-calibrated flux linkage lookup table, and further calculate the first torque estimate based on the first operating parameters and the rotor flux linkage value.

[0017] The second torque estimation unit is configured to determine the current power loss of the motor based on the three-phase current, the bus voltage and the motor speed according to a pre-calibrated power loss table, and further calculate the second torque estimation value based on the second operating parameters and the current power loss of the motor.

[0018] Advantageously, the control unit is further configured to compare the acquired motor speed with a set value, wherein a torque abnormality fault alarm is reported only when the condition that the second difference exceeds the second tolerance range is met, provided that the acquired motor speed is greater than the set value.

[0019] Advantageously, the control unit is further configured to:

[0020] The obtained motor speed is compared with the set value;

[0021] When the obtained motor speed is greater than the set value, it is determined whether the second difference falls within the second tolerance range. If the second difference exceeds the second tolerance range, a torque abnormality fault is reported; and

[0022] When the obtained motor speed is less than or equal to the set value, it is determined whether the second difference falls within the third tolerance range. If the second difference exceeds the third tolerance range, a torque abnormality fault is reported, wherein the third tolerance range is greater than the second tolerance range.

[0023] Advantageously, the first sampling channel uses a Σ-Δ analog-to-digital converter to acquire the first operating parameters of the motor from the at least one sensor; and / or, the second sampling channel uses a progressively larger approximating analog-to-digital converter to acquire the second operating parameters of the motor from the at least one sensor.

[0024] Advantageously, the device further includes:

[0025] The first verification module is used to detect the validity of the torque request value received from the vehicle's CAN bus; and / or

[0026] The second verification module is used to verify the rationality of the first working parameter and the second working parameter.

[0027] According to a second aspect of the present invention, a high-voltage inverter for a vehicle is also provided, the high-voltage inverter comprising:

[0028] A driver, configured to drive a motor to perform a rotational operation; and

[0029] The inverter main control chip includes a motor torque monitoring device according to any one of claims 1 to 7, and is configured to control the driver based on the torque monitoring result of the device to cause the motor to enter a corresponding safety protection state.

[0030] Advantageously, the inverter main control chip is further configured to adjust the motor torque output in real time based on the difference between the first torque estimate and the torque request value.

[0031] According to a third aspect of the present invention, a method for monitoring motor torque using the motor torque monitoring device described above is also provided, the method comprising the following steps:

[0032] The input port is used to receive the motor torque request value from the vehicle CAN bus;

[0033] The first operating parameters of the motor are obtained using the first sampling channel;

[0034] Based on the first operating parameters and the motor design parameters, determine the first estimated value of the motor torque;

[0035] Calculate the first difference between the first estimated torque value and the requested torque value;

[0036] The second operating parameters of the motor are obtained using the second sampling channel;

[0037] The second estimated value of the motor torque is determined based on the second operating parameters;

[0038] Calculate the second difference between the second torque estimate and the first torque estimate; and

[0039] Determine whether the first difference and the second difference fall within their respective tolerance ranges. If any of the following conditions are met, the control unit sends a torque abnormality fault alarm and controls the motor to enter a safety protection state:

[0040] The first difference between the first estimated torque value and the requested torque value exceeds the first tolerance range; and

[0041] The second difference between the second torque estimate and the first torque estimate exceeds the second tolerance range.

[0042] The motor torque estimation device and method according to the present invention combine the characteristics of two torque estimation methods, namely the flux linkage method and the power method. It can improve the availability and safety of the whole vehicle without increasing hardware costs and meets the requirements of functional safety level ASIL D. The method can achieve good torque anomaly identification effect under different motor operating conditions, and avoid the safety problems caused by abnormal motor torque output to the greatest extent, thereby improving the safety of vehicle driving. Attached Figure Description

[0043] By incorporating the figures in this article and subsequently the appendix Figure 1 The specific embodiments used to illustrate certain principles of the invention will make other features and advantages of the method of the invention clearer or more specifically explained.

[0044] Figure 1 The software architecture of a common high-voltage inverter main control chip in the prior art is shown.

[0045] Figure 2 A flowchart of the torque monitoring device in Level 2 according to the present invention is shown.

[0046] Figure 3 A high-voltage inverter torque monitoring method according to the present invention is shown. Detailed Implementation

[0047] A method and apparatus for monitoring the torque of a vehicle high-voltage inverter based on functional safety according to an embodiment of the present invention are described below with reference to the accompanying drawings. In the following description, numerous specific details are set forth to enable those skilled in the art to gain a more complete understanding of the invention. However, it will be apparent to those skilled in the art that implementation of the invention may not include some of these specific details. Furthermore, it should be understood that the invention is not limited to the specific embodiments described. Rather, the invention can be conceived to be practiced with any combination of the following features and elements, regardless of whether they relate to different embodiments. Therefore, the following aspects, features, embodiments, and advantages are illustrative only and should not be construed as elements or limitations of the claims unless expressly set forth in the claims.

[0048] In the era of vehicle intelligence, to improve the safety of vehicle electronic and electrical products, the international standard ISO 26262, "Road Vehicles - Functional Safety," is commonly used. ASIL (Automotive Safety Integrity Level) represents a vehicle safety level, and it is a risk classification system defined by the ISO 26262 standard for the functional safety of road vehicles. ASIL characterizes a product's ability to avoid unreasonable risks. It is divided into four levels: A, B, C, and D, where ASIL A represents the lowest level of vehicle hazard, and ASIL D represents the highest level of vehicle danger. In addition, there are safety requirements (QM), but QM only indicates that development follows a general quality system (such as ISO 9001, IATF 16949), and is not an ASIL level; it only requires compliance with quality management processes.

[0049] For vehicle functional safety, the goal is to control the risk of personal injury caused by the failure of electronic and electrical systems within a reasonable range. Failures in electronic and electrical systems typically include both systemic failures due to software and hardware design errors and failures caused by random hardware malfunctions. Depending on the system architecture, various safety mechanisms need to be designed to prevent and detect functional failures, and to avoid or reduce harm when such failures occur. This necessitates a robust functional safety software architecture to manage and control these safety mechanisms, reducing the overall development complexity of functional safety systems. Currently, E-GAS (Standardized E-Gas Monitoring Concept for Gasoline and Diesel Engine Control Units) is one of the most widely used safety software architecture solutions.

[0050] Figure 1This diagram illustrates a common three-layer E-GAS software architecture found in existing high-voltage inverter main control chips. This three-layer E-GAS software architecture is divided into three levels from top to bottom: Level 1 performs complex torque function control (QM requirements), Level 2 monitors torque to ensure torque safety targets and prevent unexpected acceleration, deceleration, and other hazards (ASIL C or higher), and Level 3 is the underlying hardware monitoring (ASIL C or higher). Typically, a functional safety main chip with ASIL D safety level and an external power monitoring chip are used to ensure the safety level of Level 3.

[0051] During the torque monitoring process at level 2, the estimated motor output torque is compared with the requested torque from the vehicle controller. If the difference between the two exceeds a predetermined tolerance range, the motor enters a safety protection state.

[0052] Common methods for estimating motor torque include the flux linkage method and the power method. However, these two methods have certain limitations: On the one hand, while the flux linkage method offers high accuracy, it can lead to significant discrepancies between the estimated and actual torque when the motor experiences zero-angle deviation or a decrease in the permeability of the permanent magnet, making it difficult to accurately identify abnormal torque conditions and potentially causing unexpected vehicle deceleration. On the other hand, the power method, due to algorithmic limitations, can result in large discrepancies between the estimated and actual torque under low-speed, high-torque conditions, easily causing unexpected vehicle shutdown.

[0053] The limitations of the aforementioned torque estimation methods result in low accuracy in existing motor torque monitoring methods. Under certain motor operating conditions, they may fail to accurately identify abnormal torque conditions or easily lead to false alarms, thus affecting the overall vehicle safety. This invention aims to solve one or more problems in existing torque monitoring methods by proposing a new motor torque monitoring method that meets functional safety ASIL C or ASIL D requirements. For example, torque monitoring can be performed at level 2 based on an ASIL D inverter main control chip and a power monitoring chip.

[0054] Figure 2 An architectural diagram of a torque monitoring device according to an exemplary embodiment of the present invention is shown. This torque monitoring device can, for example, be integrated as a separate hardware module into the main control chip of a high-voltage inverter for real-time monitoring of motor torque during motor operation.

[0055] The unique feature of this torque monitoring architecture is that the motor torque can be estimated using both the flux linkage method and the power method within the high-voltage inverter's main control chip. The estimation results from these two methods are then cross-checked to accurately identify the actual motor torque output. In the flux linkage method, the flux linkage information is first determined using the motor's operating parameters, and then the motor torque is estimated using this information (e.g., based on the motor's flux linkage-torque characteristic curve or a lookup table). In the power method, the motor power loss is calculated based on the motor's operating parameters, and then the motor torque is calculated based on this power loss. This process does not require obtaining the internal flux linkage value of the motor.

[0056] In this paper, the "power loss" of the motor can be determined using conventional loss calculation methods. For example, it can be predetermined based on a combination of factors such as the motor's current three-phase voltage, three-phase current, speed, hysteresis loss, copper loss, and motor load. It is worth noting that the core concept of this invention is not about how to calculate "power loss," "motor flux linkage," or "motor power," but rather about using two torque estimation results to cross-check each other, thereby improving the overall accuracy of torque anomaly identification results.

[0057] The following reference Figure 2 This article details the working principle of the torque monitoring device.

[0058] First, the vehicle's CAN bus can communicate with the high-voltage inverter's main control chip via the input port. When a torque request signal (in the form of a CAN message) is received from the CAN bus through the input port, an E2E verification module can be used to perform end-to-end verification of the CAN message. E2E verification can effectively detect whether errors or tampering have occurred in the CAN message during transmission, thereby improving the reliability and security of signal transmission.

[0059] The torque monitoring device may further include a first sampling channel and a second sampling channel, used to acquire the first operating parameter and the second operating parameter of the motor, respectively. Here, the first operating parameter includes at least one of the three-phase current of the motor, the rotor position signal, and the rotor temperature, and the second operating parameter may include at least one of the three-phase current of the motor, the motor speed, the bus voltage, the stator temperature, and the duty cycle of the PWM control signal of the motor inverter.

[0060] As an example, the first sampling channel may use a Σ-Δ analog-to-digital converter (Σ-ΔADC) to obtain the corresponding operating parameters from a sensor (e.g., a current sensor, a motor position sensor, a thermometer, etc. located inside a high-voltage inverter), while the second sampling channel may use a successive approximation analog-to-digital converter (ADC) to obtain the corresponding operating parameters from a sensor (e.g., a voltage sensor, a motor position sensor, etc.).

[0061] Among them, Σ-Δ ADC is an ADC based on oversampling technology. It digitizes the signal by high-rate oversampling of the input signal and then using Σ-Δ modulation. The Σ-Δ modulator converts the input signal into a 1-bit bitstream, which is then averaged by a digital filter to obtain a high-resolution digital output. Σ-Δ ADCs typically have high resolution and low sampling rate, making them suitable for applications requiring high precision and noise immunity.

[0062] A successive approximation ADC is a common type of high-precision, high-speed ADC that works by progressively approximating the digital representation of the input analog signal. This ADC approximates the actual value of the input signal bit by bit, thus converting the analog signal into a digital signal. The successive approximation ADC gradually adjusts the comparison bits until it achieves a digital representation that is closest to the input signal, thereby enabling high-precision analog-to-digital conversion.

[0063] Similarly, before processing and calculating the working parameters obtained from the first and second sampling channels, a rationality check operation can be performed on these parameters to ensure the reliability of the sampling results.

[0064] The operating parameters acquired from the first and second sampling channels can be transmitted to the first and second torque estimation units, respectively. In the first torque estimation unit, for example, the flux linkage method can be used to estimate the motor torque. Specifically, the first torque estimation unit can determine the rotor flux linkage value based on a portion of the first operating parameters (e.g., three-phase current and rotor temperature) according to a flux linkage lookup table, and further determine the first torque estimate of the motor based on the rotor flux linkage value, motor design parameters (e.g., number of motor pole pairs, etc.) and another portion of the first operating parameters (e.g., three-phase current, inductance).

[0065] In the second torque estimation unit, for example, the power method can be used to estimate the motor torque. Specifically, the second torque estimation unit can determine the current power loss of the motor based on a portion of the second operating parameters (e.g., three-phase current, bus voltage, and motor speed) according to a pre-calibrated power loss table, and determine the second torque estimate of the motor based on the power loss and another portion of the second operating parameters (e.g., bus voltage and three-phase current).

[0066] Furthermore, the device may also include a first calculation unit, a second calculation unit, and a control unit. The first calculation unit can be used to calculate a first difference between a first torque estimate and a torque request value received from the input port, and the second calculation unit can be used to calculate a second difference between a second torque estimate and the first torque estimate. The difference calculation results from the first and second calculation units can be further sent to the control unit, where a judgment operation can be performed regarding whether the first and second differences fall within the corresponding tolerance range.

[0067] Under any of the following conditions, the control unit may, for example, send a torque anomaly fault alarm to the CAN bus and control the motor to enter the corresponding safety protection state (e.g., active short circuit state or freewheeling state):

[0068] The first difference between the first torque estimate and the requested torque value exceeds the first tolerance range; and

[0069] The second difference between the second torque estimate and the first torque estimate exceeds the second tolerance range.

[0070] According to an optional embodiment of the present invention, in the process of torque determination, in addition to considering the difference between the flux linkage estimation result and the power estimation result, the current speed of the motor can also be considered, and the overall condition of the motor torque output can be judged based on the combined result of the two.

[0071] As an example, a torque anomaly alarm is only reported when the second difference exceeds the second tolerance range, provided that the obtained motor speed is greater than the set value. Conversely, if the motor speed is less than the set value, it is assumed that the difference between the two torque estimates will not have a serious impact on vehicle operation, so no torque anomaly alarm is sent.

[0072] As another alternative example, when the obtained motor speed is greater than the set value, the control unit can further determine whether the second difference falls within the second tolerance range. If the second difference exceeds the second tolerance range, a torque abnormality fault is reported. When the obtained motor speed is less than or equal to the set value, the control unit can alternatively determine whether the second difference falls within the third tolerance range (assuming that the third tolerance range is greater than the second tolerance range). If the second difference exceeds the third tolerance range, a torque abnormality fault is reported. In other words, compared to high motor speeds, at low motor speeds, the control unit can accept / allow a larger difference between the two torque estimation results.

[0073] In this document, the term "tolerance range" is a broad term and is given its common and customary meaning to those skilled in the art, without limitation any specific or customary meaning. Specifically, the term may refer to, but is not limited to, the range of permissible errors or deviations in a particular manufacturing, measurement, or design process, typically defined by upper and lower limits. For example, the statement "the third tolerance range is greater than the second tolerance range" specifically means that the second tolerance range falls within the third tolerance range; that is, the upper limit of the second tolerance range is less than the upper limit of the third tolerance range, and the lower limit of the second tolerance range is greater than the lower limit of the third tolerance range.

[0074] Figure 3 A flowchart illustrating the operation of a motor torque estimation method according to an exemplary embodiment of the present invention is shown. In this estimation method, in addition to comparing the requested vehicle torque value with the torque calculated using the flux linkage method, the torque calculated using the flux linkage method is also compared with the torque calculated using the power method. If either of the two comparison results fails to meet the requirements, or if neither comparison result meets the requirements, a torque abnormality fault alarm is reported to the vehicle's CAN bus, and the motor drive mechanism is controlled to put the motor into a corresponding safety protection state, for example, shutting down the three-phase full-bridge drive circuit.

[0075] First, when a torque request signal (in the form of a CAN message) is received from the CAN bus via the input port, the data sampling and torque estimation processes under the two algorithms mentioned above can be triggered.

[0076] Specifically, in the flux linkage estimation: the first channel (e.g., Σ-ΔADC) is used to sample the three-phase current and rotor position signals. The flux linkage torque is calculated based on the phase current, rotor position signal, motor rotor temperature and related parameters, and compared with the requested torque of the whole vehicle. If it exceeds the tolerance range T0 (also referred to as the "first tolerance range" in this article), the motor is put into a safe state and a fault is reported.

[0077] In the power estimation process: First, a second channel (e.g., a successive approximation ADC) is used to sample the three-phase current, motor speed, and bus voltage. The power estimation result is obtained based on the phase current, motor speed, bus voltage, motor stator temperature, and PWM signal duty cycle. Then, the acquired motor speed is compared with a set speed n1. When the speed is less than n1, the power estimation result is compared with the flux linkage estimation result. If the difference exceeds the tolerance range T1 (also referred to as the "third tolerance range"), the motor enters a safe state and a fault is reported. When the speed is greater than or equal to n1, the power estimation result is compared with the flux linkage estimation result. If the difference exceeds the tolerance range T2 (also referred to as the "second tolerance range"), the motor enters a safe state and a fault is reported. Here, the tolerance range T1 can be set to be greater than T2 because at low motor speeds, the control unit can accept / allow a larger difference between the two torque estimation results.

[0078] The motor torque estimation device and method according to the present invention combine the characteristics of two torque estimation methods, namely the flux linkage method and the power method. It can improve the availability and safety of the whole vehicle without increasing hardware costs and meets the requirements of functional safety level ASIL D. The method can achieve good torque anomaly identification effect under different motor operating conditions, and avoid the safety problems caused by abnormal motor torque output to the greatest extent, thereby improving the safety of vehicle driving.

[0079] Those skilled in the art will understand that the method steps described in this invention can be performed in a given order. However, it should be noted that different orders are also possible. The method may include additional method steps not listed. Furthermore, one or more of the method steps may be performed once or repeatedly. Additionally, two or more of the method steps may be performed simultaneously or in overlapping time. Furthermore, in this invention, terms such as "comprising" and "including" indicate that the technical solution of this application does not exclude the presence of other steps not directly or explicitly stated, in addition to the steps directly and explicitly stated in the specification and claims.

[0080] While the present invention has been disclosed above with reference to preferred embodiments, it is not limited thereto. Any modifications and alterations made by those skilled in the art without departing from the spirit and scope of the invention should be included within the scope of protection of the invention. Therefore, the scope of protection of the invention should be determined by the scope defined in the claims.

Claims

1. An electric motor torque monitoring device, characterized by, The apparatus comprises: an input port configured to receive a torque request value of the electric machine from a vehicle CAN bus; a first sampling channel and a second sampling channel configured to acquire a first operating parameter and a second operating parameter of the electric machine from at least one sensor, respectively; a first torque estimation unit configured to determine a first torque estimation value of the electric machine according to the first operating parameter and electric machine design parameters; a first calculation unit configured to calculate a first difference between the first torque estimation value and the torque request value; a second torque estimation unit configured to determine a second torque estimation value of the electric machine according to the second operating parameter; a second calculation unit configured to calculate a second difference between the second torque estimation value and the first torque estimation value; and a control unit configured to determine whether the first difference and the second difference fall within a corresponding tolerance range, wherein the control unit is further configured to send a torque abnormality fault alarm and control the electric machine to enter a safety protection state if any of the following conditions is met: the first difference between the first torque estimation value and the torque request value exceeds a first tolerance range; and the second difference between the second torque estimation value and the first torque estimation value exceeds a second tolerance range.

2. The electric machine torque monitoring apparatus according to claim 1, wherein the electric machine design parameters comprise a number of pole pairs of the electric machine, the first operating parameter comprises at least one of three-phase currents of the electric machine, a rotor position signal and a rotor temperature, and the second operating parameter comprises at least one of the three-phase currents of the electric machine, a motor speed, a bus voltage, a stator temperature and a duty cycle of a PWM control signal of an electric machine inverter.

3. The electric machine torque monitoring apparatus according to claim 2, wherein the first torque estimation unit is configured to determine a rotor flux value based on the three-phase currents and the rotor temperature according to a pre-calibrated flux lookup table, and further calculate the first torque estimation value based on the first operating parameter and the rotor flux value, and the second torque estimation unit is configured to determine a current power loss of the electric machine based on the three-phase currents, the bus voltage and the motor speed according to a pre-calibrated power loss table, and further calculate the second torque estimation value based on the second operating parameter and the current power loss of the electric machine.

4. The electric machine torque monitoring apparatus of claim 2, wherein, the control unit is further configured to: compare the acquired motor speed with a set value, and only report the torque abnormality fault alarm when the condition that the second difference exceeds the second tolerance range is met on the premise that the acquired motor speed is greater than the set value.

5. The electric machine torque monitoring apparatus of claim 2 wherein, the control unit is further configured to: compare the acquired motor speed with a set value; when the acquired motor speed is greater than the set value, determine whether the second difference falls within the second tolerance range, and report the torque abnormality fault if the second difference exceeds the second tolerance range; and ​ When the acquired motor speed is less than or equal to the set value, it is determined whether the second difference value falls within a third tolerance range, and if the second difference value exceeds the third tolerance range, a torque abnormality fault is reported, wherein the third tolerance range is greater than the second tolerance range.

6. The electric machine torque monitoring apparatus according to any one of claims 1 to 5, characterized by, The first sampling channel uses a sigma-delta type analog-to-digital converter to acquire a first operating parameter of the motor from the at least one sensor; and / or the second sampling channel uses a successive approximation type analog-to-digital converter to acquire a second operating parameter of the motor from the at least one sensor.

7. The electric machine torque monitoring apparatus of any one of claims 1 to 5, wherein, The device further comprises: a first verification module configured to detect the validity of a torque request value received from the vehicle CAN bus; and / or a second verification module configured to perform rationality verification on the first operating parameter and the second operating parameter.

8. A high voltage inverter for a vehicle, characterized by, The high-voltage inverter comprises: a driver configured to drive the motor to perform a rotating operation; and an inverter master control chip comprising the motor torque monitoring device according to any one of claims 1 to 7, and configured to control the driver to make the motor enter a corresponding safety protection state based on the torque monitoring result of the device.

9. The high voltage inverter of claim 8, wherein, The inverter master control chip is further configured to adjust the torque output of the motor in real time according to the difference between the first torque estimation value and the torque request value.

10. A method of monitoring the torque of an electric machine using the electric machine torque monitoring device according to any one of claims 1 to 7, characterized in that, The method comprises the following steps: receiving a torque request value of the motor from the vehicle CAN bus through the input port; acquiring a first operating parameter of the motor using the first sampling channel; determining a first torque estimation value of the motor based on the first operating parameter and motor design parameters; calculating a first difference value between the first torque estimation value and the torque request value; acquiring a second operating parameter of the motor using the second sampling channel; determining a second torque estimation value of the motor based on the second operating parameter; calculating a second difference value between the second torque estimation value and the first torque estimation value; and determining whether the first difference value and the second difference value fall within their respective tolerance ranges, wherein in the case where any one of the following conditions is met, a torque abnormality fault alarm is sent through the control unit and the motor is controlled to enter a safety protection state: the first difference value between the first torque estimation value and the torque request value exceeds a first tolerance range; and the second difference value between the second torque estimation value and the first torque estimation value exceeds a second tolerance range.

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