DESC:FAULT DIAGNOSTICS SYSTEM FOR DRIVE TRAIN UNIT
CROSS REFERENCE TO RELATED APPLICATIONS
The present application claims priority from Indian Provisional Patent Application No. 202421079817 filed on 21/10/2024, the entirety of which is incorporated herein by a reference.
TECHNICAL FIELD
The present disclosure generally relates to a Drive Train Unit (DTU) of electric vehicles. Particularly, the present disclosure relates to system(s) and method(s) for fault diagnostic of the DTU of electric vehicles.
BACKGROUND
In recent years, the adoption of electric vehicles (EVs) has grown rapidly due to increasing environmental concerns, advancements in battery technology, and supportive government policies. At the core of an EV’s propulsion system is the DTU, which integrates components such as the electric motor, power electronics, and transmission mechanisms to convert electrical energy from the battery into mechanical energy for vehicle motion, and vice versa during regenerative braking.
Generally, the electric drive system serves as a critical component in the mutual conversion of electrical energy and mechanical energy in electric vehicles (EVs). The operational status of the electric drive system directly impacts the reliability, performance, and safety of the vehicle. One of the fundamental safety objectives in such systems is the prevention of unexpected torque generation, which may adversely affect the vehicle control and passenger safety. When an unexpected torque fault occurs in the electric drive system, the system need to transition into a designated safe state to prevent further risk. Commonly, the safe states transitions may include, but not limited to, an Active Short Circuit (ASC), a Three-phase Open Circuit (Free Wheeling, FW), and a Torque Limit Control. In the ASC safe state, the three upper-arm switches of the inverter’s Insulated Gate Bipolar Transistor (IGBT) bridge are simultaneously turned off, and the three lower-arm switches are turned on. This configuration generates a significant braking torque at low motor speeds, which may negatively impact driving comfort. Further, the continuous current produced by the motor’s Counter Electro-Motive Force (CEMF) may cause excessive heating, potentially leading to motor demagnetization, inverter damage, or other component failures. At high motor speeds, ASC results in only a small braking torque and no CEMF generation. Furthermore, in the FW safe state, the three motor phases are placed in an open-circuit condition. This produces a small braking torque at low speeds but a large braking torque and significant CEMF at high speeds, resulting in high CEMF which may causes an overvoltage on the DC bus, leading to potential damage of bus-connected devices. Moreover, the torque limiting control refers to a safety mode in which, despite normal high- and low-voltage supply conditions, the torque output is restricted in response to certain detected faults. This reduces the load on the battery and maintains the electric drive system within safe operating limits, such as avoiding thermal overload. Subsequently, in existing technologies, the selection of the safe state in response to faults is typically limited to either ASC or FW, without integrating torque limiting control into the safety strategy. Additionally, the choice of safe state is generally based solely on the detection of IGBT module fault. Such approaches may result in suboptimal switching between safe states, potentially introducing safety hazards or degrading the driver’s experience.
Therefore, there exists a need for a system and method for fault diagnostics of a DTU and associated components that overcomes one or more problems associated as set forth above.
SUMMARY
An object of the present disclosure is to provide a system for fault diagnostics of a Drive train Unit (DTU).
Another object of the present disclosure is to provide a method for fault diagnostics of a Drive Train Unit (DTU).
In accordance with first aspect of the present disclosure, there is provided a system for fault diagnostics of a Drive Train Unit (DTU). The system comprising a plurality of sensors and a processor. The plurality of sensors are configured to detect at least one fault associated with the DTU. Further, the processor is configured to compute a demand torque, compare a filtered demand torque with an actual torque, and process the filtered demand torque and implement safety measures based on the detected faults and processed demand torque.
The present disclosure provides the system for fault diagnostics of the DTU. The system as disclosed in present disclosure is advantageously providing a comprehensive and intelligent fault diagnostic for the DTU of the electric vehicle. Beneficially, the system enabling early detection and accurate identification of a wide range of electrical, electronic, and mechanical faults. Further, the system ensures precise monitoring of operating conditions and immediate detection of unintended acceleration or deceleration events. Furthermore, the system significantly enhances the vehicle safety, prevents component damage, and improves operational reliability. Moreover, the system ensures smooth and controlled fault response, thereby minimizing adverse impacts on the driver’s experience while maintaining the DTU within safe operating limits. Additionally, the holistic approach of the system reduces downtime, extends component life, and supports compliance with functional safety standards in modern electric vehicles.
In accordance with second aspect of the present disclosure, there is provided a method for fault diagnostics of a DTU. The method comprising detecting at least one fault associated with the DTU, detecting an unintended acceleration and/or deceleration, computing demand torque and processing filtered demand torque.
Additional aspects, advantages, features and objects of the present disclosure would be made apparent from the drawings and the detailed description of the illustrative embodiments constructed in conjunction with the appended claims that follow.
It will be appreciated that features of the present disclosure are susceptible to being combined in various combinations without departing from the scope of the present disclosure as defined by the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein. Moreover, those in the art will understand that the drawings are not to scale. Wherever possible, like elements have been indicated by identical numbers.
Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams wherein:
FIG. 1 illustrates a block diagram of a system for fault diagnostics of a Drive Train Unit (DTU), in accordance with an embodiment of the present disclosure.
FIG. 2 illustrates a flow chart of a steps involved in a method for fault diagnostics of a Drive Train Unit (DTU) and associated components, in accordance with an embodiment of the present disclosure.
In the accompanying drawings, an underlined number is employed to represent an item over which the underlined number is positioned or an item to which the underlined number is adjacent. A non-underlined number relates to an item identified by a line linking the non-underlined number to the item. When a number is non-underlined and accompanied by an associated arrow, the non-underlined number is used to identify a general item at which the arrow is pointing.
DETAILED DESCRIPTION
The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognise that other embodiments for carrying out or practising the present disclosure are also possible.
The description set forth below in connection with the appended drawings is intended as a description of certain embodiments of a system and a method for fault diagnostics of a Drive Train Unit (DTU) and is not intended to represent the only forms that may be developed or utilised. The description sets forth the various structures and/or functions in connection with the illustrated embodiments; however, it is to be understood that the disclosed embodiments are merely exemplary of the disclosure that may be embodied in various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimised to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the present invention.
While the disclosure is susceptible to various modifications and alternative forms, specific embodiment thereof has been shown by way of example in the drawings and will be described in detail below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.
In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings and which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.
The present disclosure will be described herein below with reference to the accompanying drawings. In the following description, well known functions or constructions are not described in detail since they would obscure the description with unnecessary detail.
As used herein, the terms “electric vehicle”, “EV”, and “EVs” are used interchangeably and refer to any vehicle having stored electrical energy, including the vehicle capable of being charged from an external electrical power source. This may include vehicles having batteries which are exclusively charged from an external power source, as well as hybrid-vehicles which may include batteries capable of being at least partially recharged via an external power source. Additionally, it is to be understood that the ‘electric vehicle’ as used herein includes electric two-wheeler, electric three-wheeler, electric four-wheeler, electric pickup trucks, electric trucks and so forth.
As used herein, the term “fault diagnostics” refers to a process of detecting, identifying, and, where applicable, classifying abnormal conditions, malfunctions, or failures in a system or the components by monitoring one or more operational parameters, comparing the monitored parameters with predefined thresholds or reference values, and analyzing deviations to determine the nature, location, and severity of the fault. The fault diagnostics may include both real-time monitoring for immediate response and post-event analysis for preventive maintenance, and may be applied to electrical, electronic, mechanical, or software subsystems.
As used herein, the terms “Drive Train Unit” and “DTU” are used interchangeably and refer to an integrated assembly in the electric vehicle that is configured to convert electrical energy from an energy storage system into mechanical energy for propulsion, and to convert mechanical energy into electrical energy during regenerative braking. The DTU typically comprises one or more of an electric motor, a power electronics module (including an inverter and control circuitry), a transmission or gear reduction mechanism, and associated sensors, actuators, and control systems. The DTU may be implemented as a single housing or as a combination of interconnected components, and is operable to control torque delivery to the vehicle’s wheels in accordance with driving demands and operational safety requirements.
As used herein, the terms “plurality of sensors” and “sensors” are used interchangeably and refer to two or more sensing devices configured to measure, detect, or monitor one or more physical, electrical, or environmental parameters associated with the DTU or the related components. The plurality of sensors may include, but is not limited to, wheel speed sensors, voltage sensors, current sensors, temperature sensors, position sensors, and other types of sensors capable of detecting operating conditions, faults, or abnormal states in the system. The plurality of sensors may operate independently or in combination, may be located at different positions within the vehicle, and may communicate with a processor through wired or wireless interfaces to provide real-time or near real-time data for analysis and fault diagnostics.
As used herein, the terms “at least one fault” and “detected fault(s)” are used interchangeably and refer to any abnormal condition, malfunction, or deviation from expected operational parameters of the DTU or the associated components, as identified through sensor measurements, signal analysis, or diagnostic algorithms. Such faults may include, but are not limited to, electrical faults (e.g., under-voltage, over-voltage, over-current, short circuits), electronic control faults (e.g., CPU errors, watchdog timeouts, flash memory corruption, gate driver failures), sensor-related faults (e.g., position sensor errors, throttle malfunctions, communication failures), thermal faults (e.g., motor or inverter over-temperature), mechanical faults (e.g., motor system anomalies), and system-level faults in associated subsystems such as a Battery Management System (BMS) or Onboard Charger (OBC).
As used herein, the terms “processor”, “processing unit”, “control unit”, and “controller” are used interchangeably and refer to any suitable computational unit or electronic circuitry configured to execute instructions, process data, and perform logic-based operations. The processor may include, but is not limited to, a microcontroller, microprocessor, Digital Signal Processor (DSP), Application-Specific Integrated Circuit (ASIC), Field-Programmable Gate Array (FPGA), or any combination thereof. The processor may be configured to operate independently or in conjunction with other hardware or software components, and may include associated memory, communication interfaces, and input/output modules as required for executing specific control, diagnostic, or computational tasks within the system.
As used herein, the term “demand torque” refers to a torque value requested by a control system of the electric vehicle, representing the desired rotational force to be produced by the electric motor in response to input signals such as accelerator pedal position, regenerative braking command, or other control parameters. The demand torque is typically calculated by a vehicle control unit based on driver inputs, vehicle operating conditions, and predefined control strategies, and serves as a reference for the motor control algorithm to regulate motor output torque accordingly.
As used herein, the term “filtered demand torque” refers to a torque command value derived from an initial demand torque signal, wherein the initial demand torque signal is subjected to one or more filtering processes to remove noise, transient spikes, and other undesired signal variations. The filtering may be implemented through hardware or software-based signal processing techniques, including, but not limited to, low-pass filtering, moving average filtering, or digital smoothing algorithms, so as to obtain a stable and accurate representation of the driver’s or control system’s intended torque request.
As used herein, the term “actual torque” refers to the instantaneous torque output of the electric motor in the DTU, measured or estimated based on real-time operating parameters such as motor phase current, voltage, rotor position, and motor-specific calibration data. The actual torque represents the true mechanical torque being delivered by the motor shaft to the drivetrain, as opposed to a commanded or demand torque, and may be determined using direct torque sensing devices or indirectly calculated by the processor from sensor inputs.
As used herein, the term “safety measures” refers to actions, control strategies, or system responses executed by the processor or control unit to protect the electric drive system, associated vehicle components, and occupants from potential hazards arising from detected faults or abnormal operating conditions. Such safety measures may include, but are not limited to, reducing or limiting power or torque output, disabling or isolating the DTU or the subsystems, activating fault indicators or warnings to alert the vehicle operator, logging fault information for diagnostic purposes, initiating safe-state transitions such as Active Short Circuit (ASC), Free Wheeling (FW), or torque limit control, and controlling other vehicle systems to mitigate further risk.
As used herein, the terms “wheel speed sensor” and “speed sensor” are used interchangeably and refer to a sensing device configured to detect and generate a signal indicative of the rotational speed of a vehicle wheel or axle. The wheel speed sensor may operate based on one or more sensing principles, including but not limited to, magnetic reluctance, Hall-effect, or optical encoding, and may comprise a sensor element, signal conditioning circuitry, and associated mounting hardware. The output of the wheel speed sensor may be in the form of an analog or digital signal and is processed by a controller or processor to determine wheel rotational speed for applications such as traction control, anti-lock braking, vehicle stability control, and drive train unit fault diagnostics.
As used herein, the term “voltage sensor(s)” refers to a sensing device or circuitry configured to measure an electrical potential difference between two points in an electrical circuit, such as between a power supply line and a reference ground. The voltage sensor may operate using resistive, capacitive, inductive, optical, or other measurement principles, and may provide an analog or digital output representative of the measured voltage. The voltage sensor may be configured to detect DC bus voltage, phase voltage, or auxiliary supply voltage in the DTU to monitor for abnormal conditions such as over-voltage, under-voltage, or voltage fluctuations.
As used herein, the term “current sensor(s)” refers to a device or component configured to detect, measure, and/or monitor the magnitude of electric current flowing through a conductor, circuit, or electrical component, and to generate a corresponding output signal representative of the measured current. The current sensor may operate based on one or more sensing principles, including but not limited to, shunt resistor voltage drop measurement, Hall effect sensing, Rogowski coil sensing, or magnetic field detection. The output of the current sensor may be provided in analog or digital form for further processing by the processor, or diagnostic system.
As used herein, the term “temperature sensor(s)” refers to a device or component configured to measure the temperature of a target element, medium, or environment, and to generate a corresponding electrical signal indicative of the measured temperature. The temperature sensor may be based on any suitable sensing principle, including but not limited to, thermocouples, Resistance Temperature Detectors (RTDs), thermistors, semiconductor-based temperature sensors, or infrared temperature sensors, and may be configured to directly or indirectly monitor the temperature of components such as a motor, inverter, battery, power electronics, or ambient surroundings.
As used herein, the term “position sensor(s)” refers to a sensing device configured to detect and provide a signal indicative of the position, displacement, or angular orientation of a movable component within the DTU or an associated system. The position sensor may detect absolute or relative position and may employ one or more sensing principles, including but not limited to, magnetic sensing (e.g., Hall-effect sensor), optical sensing (e.g., encoder), capacitive sensing, inductive sensing, or potentiometric sensing.
As used herein, the term “DC under voltage” refers to a condition in which the Direct Current (DC) voltage of the high-voltage bus or power supply in the electric drive system falls below a predefined threshold value, such threshold being determined based on the operational requirements of the DTU and associated components. Such a condition may arise due to, but is not limited to, battery discharge, high load demand, connection faults, or failures in the power supply circuitry, and may lead to reduced performance, malfunction, or shutdown of the electric drive system if not promptly detected and mitigated.
As used herein, the term “DC over voltage” refers to a condition in which the DC voltage level present in the high-voltage bus, battery pack, or other DC electrical system of the electric vehicle exceeds a predefined maximum allowable threshold value. Such a condition may arise due to factors including, but not limited to, regenerative braking energy feedback, charger malfunction, battery management system failure, or sudden load disconnection. The prolonged or excessive DC over-voltage may cause insulation breakdown, component overheating, inverter or power electronics damage, and potential safety hazards, thereby requiring immediate detection and protective action by the system.
As used herein, the term “phase over current” refers to an electrical fault condition in which the current flowing through any individual phase of a multi-phase electric motor, typically in a three-phase drive system, exceeds a predetermined safe operating threshold. Such excessive current may result from abnormal load conditions, short circuits, inverter switching faults, or control malfunctions, and may cause the overheating, insulation breakdown, or permanent damage to motor windings and associated power electronics. The detection of phase over-current is typically achieved using current sensors positioned in each motor phase, with the measured values compared against calibrated threshold limits in real-time by the control system.
As used herein, the term “short circuit(s)” refers to an abnormal electrical condition in which a low-resistance conductive path is unintentionally established between two points in an electric circuit that are normally at different potentials. The short circuit condition causes excessive current flow beyond the designed operating limits of the circuit, which may result in overheating, component damage, fire hazards, or operational failure of the system. The short circuit may occur between conductors, between a conductor and ground, or across the terminals of an electrical component, and can be caused by insulation failure, conductor damage, manufacturing defects, or environmental factors.
As used herein, the term “motor over temperature” refers to a condition in which the temperature of the motor, or one or more components thereof such as the stator windings, rotor, or bearings, exceeds a predetermined safe operating threshold. Such a condition may arise due to factors including, but not limited to, excessive current draw, inadequate cooling, mechanical overload, or prolonged high-speed operation. When motor over-temperature occurs, thermal stress may degrade insulation, demagnetize permanent magnets, damage bearings, or cause other irreversible performance losses, thereby necessitating detection and corrective action to prevent permanent damage or operational failure.
As used herein, the term “position sensor failure” refers to a fault condition in which the position sensor, configured to detect the rotational position, angular displacement, or speed of a component of the DTU such as the motor rotor or transmission shaft, provides erroneous, inconsistent, or no output signal. Such failure may result from causes including, but not limited to, sensor element degradation, electrical disconnection, short-circuiting, signal noise interference, magnetic field distortion, mechanical misalignment, or calibration errors. The position sensor failure may lead to incorrect torque control, loss of synchronization in motor commutation, or inability to determine the correct operating state of the DTU, thereby affecting the safety and performance of the electric vehicle.
As used herein, the term “throttle malfunction(s)” refers to any abnormal condition, fault, or deviation in the operation of the electric vehicle’s throttle system comprising throttle input devices such as accelerator pedals, throttle position sensors, associated signal processing circuits, and communication interfaces that results in incorrect, delayed, or unintended transmission of torque demand signals to the drive control system. Such malfunctions may include, but are not limited to, sensor signal drift, loss of signal, short-circuit or open-circuit faults, out-of-range voltage outputs, mechanical sticking or misalignment of the throttle actuator, and software or communication errors affecting throttle signal interpretation.
As used herein, the terms “DTU hardware malfunctions” and “hardware malfunctions” are used interchangeably and refer to failures, defects, or abnormal operating conditions occurring in one or more physical components of the DTU, including but not limited to, the electric motor, power electronics (such as inverters, converters, and gate drivers), control modules, printed circuit boards (PCBs), connectors, wiring harnesses, cooling systems, and associated mechanical assemblies. Such malfunctions may arise from component wear, manufacturing defects, environmental stress (e.g., temperature, vibration, moisture), electrical overstress (e.g., overvoltage, overcurrent, short circuits), or signal transmission failures, resulting in degraded performance, intermittent operation, or complete loss of function of the DTU.
As used herein, the term “communication failure” refers to a condition in which data transmission between two or more electronic control units, modules, or sensors in the vehicle is interrupted, corrupted, delayed beyond acceptable limits, or otherwise rendered unreliable. Such communication failure may result from hardware faults, software errors, or signal integrity issues, and includes, but is not limited to, loss of signal, signal distortion, erroneous data frames, or protocol-specific errors in communication interfaces such as Inter-Integrated Circuit (I²C), Controller Area Network (CAN), Pulse Width Modulation (PWM), or other wired or wireless communication channels.
As used herein, the term “watchdog issue(s)” refers to a malfunction or failure condition associated with a watchdog timer in an embedded control system, wherein the watchdog timer fails to receive a required periodic reset signal from the processor within a predefined time interval. Such a condition indicates that the processor, control software, or an associated process is stuck, unresponsive, or operating outside of expected execution flow, thereby potentially compromising system functionality and safety. The watchdog issue may arise due to software hangs, infinite loops, memory corruption, hardware failures, or other abnormal execution conditions, and typically triggers a predefined recovery or safety response such as a processor reset, fault flag generation, or transition to a safe operating state.
As used herein, the term “CPU issue(s)” refers to a malfunction, fault, or abnormal operation of a Central Processing Unit (CPU) within the DTU or the associated control systems, which may impair the execution of control algorithms, data processing, or communication tasks. Such issues may include, but not limited to, processing lockups, execution halts, incorrect instruction execution, timing errors, overheating, resource conflicts, or other failures that prevent the CPU from performing its intended control and diagnostic functions in a reliable manner.
As used herein, the term “flash corruption” refers to an error condition in which the data stored in a non-volatile flash memory device, such as program code, calibration parameters, or configuration data, becomes altered, erased, or unreadable due to electrical disturbances, memory cell degradation, software malfunction, or unintended write/erase operations. Such corruption may result in incorrect execution of control algorithms, loss of critical parameters, or failure of the DTU to operate as intended.
As used herein, the term “MOSFET failure” refers to a malfunction or degradation of a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) used in the power electronics of the DTU, wherein the MOSFET is unable to perform its intended switching or current control function within specified electrical and thermal limits. Such failure may occur due to, but not limited to, conditions such as gate oxide breakdown, short-circuit between drain and source, open circuit in the conduction path, thermal runaway, excessive leakage current, or parameter drift beyond allowable tolerance, resulting in impaired operation of the inverter, motor controller, or other DTU components.
As used herein, the term “gate driver failure” refers to a malfunction or abnormal operation of a gate driver circuit. The gate driver is an interface component configured to control the switching state of a power semiconductor device such as an Insulated Gate Bipolar Transistor (IGBT) or a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET) by supplying appropriate gate voltage and current signals. The gate driver failure may result from electrical faults, thermal stress, component degradation, or control signal corruption, and may be leads to improper switching, partial conduction, failure to turn on or off the device, excessive heat generation, or permanent damage to the semiconductor device, thereby compromising the safe and reliable operation of the associated power electronics system.
As used herein, the term “DC voltage drop” refers to a reduction in the DC voltage level of an electrical circuit or system, measured between two points, which may occur due to factors such as increased electrical load, resistance in conductors or connectors, degradation of power supply components, or transient operating conditions. The DC voltage drop typically denotes an abnormal decrease in the DC bus voltage between the energy storage system and the power electronics, which may adversely affect motor performance, cause control malfunctions, or indicate faults in associated components such as the battery pack, wiring harness, connectors, or power conversion units.
As used herein, the term “Delta Torque” refers to the difference between the filtered demand torque representing the torque request after applying filtering or smoothing algorithms to the raw torque demand signal and the actual torque generated by the DTU. The Delta Torque serves as an indicator of deviation between intended and delivered torque, which may arise due to system faults, control errors, or abnormal operating conditions. Further, monitoring and evaluating Delta Torque allows the system to detect unintended acceleration or deceleration events, trigger appropriate fault flags, and initiate corresponding safety measures to maintain safe and reliable vehicle operation.
As used herein, the term “calibratable factor” refers to a predetermined numerical value or parameter that may be set, adjusted, or tuned either during system development, manufacturing, or in-field operation to meet specific performance, safety, or operational requirements of the system. The calibratable factor may be stored in a memory accessible by the processor and may be adjusted through software configuration, diagnostic tools, or control interfaces. The calibratable factor is used to determine thresholds, limits, or reference values such as the maximum allowable delta torque for fault detection or control actions. The value of the calibratable factor may vary depending on factors such as vehicle type, operating environment, or customer-specific requirements.
As used herein, the terms “unintended acceleration”, “UIA1”, and “UIA2” are used interchangeably and refer to a condition in which the electric drive system of a vehicle generates a positive torque that results in vehicle acceleration without a corresponding driver input or beyond the driver’s intended torque request. Such a condition may occur due to electrical, electronic, or control system faults, including, but not limited to, sensor malfunctions, signal processing errors, actuator failures, or software anomalies, and may lead to a mismatch between the commanded torque and the actual torque output of the DTU.
As used herein, the terms “unintended deceleration”, “UID1”, and “UID2” are used interchangeably and refer to a condition in which the vehicle experiences a reduction in speed or torque output that is not commanded by the driver or control system under normal operating conditions. Such deceleration may occur due to faults in the DTU, associated sensors, power electronics, or control logic, and may result from abnormal torque generation, excessive regenerative braking, or incorrect safety state activation. The unintended deceleration is identified when the actual torque deviates beyond a predetermined threshold from the filtered demand torque in the negative direction for a specified duration, indicating a loss of propulsion or unexpected braking action not initiated by the driver.
As used herein, the term “functional safety state” refers to a predefined operational mode of the DTU or an associated control system, in which specific control actions are executed to maintain the vehicle in a safe condition in response to a detected fault or abnormal condition. The functional safety state is determined in accordance with functional safety requirements and may involve one or more of reducing or limiting torque output, disabling propulsion, enabling regenerative braking, isolating faulty components, or maintaining controlled drivability until the fault is cleared or the vehicle is stopped. The selection and execution of the functional safety state are based on real-time operating parameters, detected fault types, and calibrated safety thresholds, ensuring compliance with safety integrity levels defined by applicable standards.
As used herein, the terms “functional safety demand torque allow”, “functional demand torque” and “demand torque allow” are used interchangeably and refer to a control signal or flag generated by the processor of the electric drive system, which authorizes the application of the demand torque to the motor based on verification that no safety-critical faults are present. The signal is determined in accordance with predefined functional safety logic and fault detection algorithms, and remains in an active (allow) state only when all monitored parameters such as electrical, thermal, mechanical, and communication conditions are within permissible operating limits. The activation of the functional safety demand torque allow ensures that torque generation is permitted in a manner compliant with the functional safety requirements of the system, thereby preventing unintended acceleration or deceleration under fault conditions.
As used herein, the terms “functional safety demand torque stop flag(s)”, “demand torque stop flag(s)”, and “torque stop flag (s)” are used interchangeably and refer to a control signal generated by the processor of the electric drive system that commands the torque output of the DTU to be reduced to zero or to a predetermined safe limit in response to detection of a fault or hazardous condition. The flag serves as a functional safety mechanism in compliance with safety control logic, and is used to immediately halt torque production by disabling or overriding torque generation commands within the Field-Oriented Control (FOC) or equivalent motor control strategy.
As used herein, the terms “Field-Oriented Control system” and “FOC system” are used interchangeably and refer to a motor control methodology in which the stator currents of an electric motor are transformed into a rotating reference frame aligned with the rotor magnetic field, enabling independent control of the torque-producing and flux-producing current components. The FOC system utilizes mathematical transformations, such as Clarke and Park transforms, along with feedback from motor position or speed sensors, to regulate the motor’s electromagnetic torque and flux with high precision. The FOC system approach provides smoother torque output, improved dynamic response, and higher efficiency compared to scalar control methods, and is applicable to various motor types including Permanent Magnet Synchronous Motors (PMSM) and induction motors.
Figure 1, in accordance with an embodiment describes a system 100 for fault diagnostics of a Drive Train Unit (DTU). The system 100 comprising a plurality of sensors 102 and a processor 104. The plurality of sensors 102 are configured to detect at least one fault associated with the DTU. Further, the processor 104 is configured to compute a demand torque, compare a filtered demand torque with an actual torque, and process the filtered demand torque and implement safety measures based on the detected faults and processed demand torque.
In an embodiment, the plurality of sensors 102 comprises a wheel speed sensor 102a, a voltage sensor 102b, a current sensor 102c, a temperature sensor 102d, and a position sensor 102e. The wheel speed sensor 102a may be configured to detect the rotational speed of the wheels, enabling precise monitoring of vehicle motion parameters. Further, the voltage sensor 102b and current sensor 102c may be configured to measure the electrical parameters of the DTU, including, but not limited to, supply voltage and phase currents, for detecting abnormalities such as under-voltage, over-voltage, or over-current conditions. Furthermore, the temperature sensor 102d may be configured to monitor the thermal status of the DTU components, preventing overheating-related failures. Moreover, the position sensor 102e may be configured to determine the rotor position or angular displacement of the motor shaft, facilitating accurate control of motor torque and speed through the FOC system. The combination of the plurality of sensors provide multi-dimensional data acquisition, enabling comprehensive fault detection across electrical, mechanical, and thermal domains of the DTU. Beneficially, the integration of wheel speed sensor 102a, the voltage sensor 102b, the current sensor 102c, the temperature sensor 102d, and the position sensor 102e into the DTU fault diagnostic system 100 provides enhanced fault detection accuracy, faster response to abnormal operating conditions, and improved reliability. Further, by simultaneously monitoring electrical, mechanical, and thermal parameters, the system 100 identify the complex fault patterns that may not be detectable through single-parameter monitoring. The identification of the complex fault patterns leads to early intervention before faults escalate, thereby minimizing the component damage and vehicle downtime. Furthermore, the use of real-time position feedback from the position sensor enhances torque control precision in the FOC system, thereby improving the vehicle drivability and safety.
In an embodiment, the plurality of sensors 102 may be configured to detect electrical faults comprising at least one of a DC under-voltage, a DC over-voltage, a phase over-current, a short circuits, a motor over-temperature, a position sensor failures, a throttle malfunctions, a DTU hardware malfunctions, and a communication failure comprising at least one of I2C, CAN, and PWM. The strategic arrangement of the plurality of sensors 102 allows the system 100 to monitor both power-related and signal-related parameters in real time, thereby enabling rapid identification of fault events that may compromise the safe operation of the DTU. Beneficially, the sensor 102 enables comprehensive and real-time detection of the wide range of electrical and communication-related faults in the DTU, covering both power delivery and control signal integrity. Further, the early detection capability of the system 100 facilitates prompt initiation of protective actions, such as torque limitation or DTU shutdown, thereby reducing the risk of damage to critical components like the motor, inverter, and control electronics. Additionally, by monitoring communication interfaces (I2C, CAN, PWM), the system 100 ensures the reliability of data transmission between subsystems, essential for accurate torque control and safe vehicle operation.
In an embodiment, the plurality of sensors 102 may be configured to detect faults comprising at least one of a watchdog issues, a CPU issues, a flash corruption, an MOSFET failures, a gate driver failures, a sensing circuit failures, and faults in associated components comprising a Battery Management System (BMS), an Onboard Charger (OBC), motor systems, a deep battery discharge, a DC voltage drop, and signal line connection problems. The comprehensive fault detection capability provided by the plurality of sensors 102 allowing the system 100 to continuously monitor the health of the DTU and related subsystems, thereby enabling timely and appropriate safety responses. Beneficially, the inclusion of the plurality of sensors 102 enabling the real-time, multi-domain fault detection across both primary DTU components and peripheral vehicle systems, thereby ensuring that potential failures are identified before the failures escalate into critical safety hazards. Further, by covering a wide fault spectrum ranging from the electronic control anomalies to powertrain and communication line issues, the system 100 enhances diagnostic accuracy and reduces the risk of undetected faults. Furthermore, the wide fault spectrum results in improved operational reliability, minimization of unplanned downtime, and prevention of damage to critical components. Moreover, the ability to detect issues in interconnected systems such as the BMS and OBC supports coordinated safety management across the power and control architecture of the vehicle, thereby leading to improved overall vehicle safety and performance stability.
In an embodiment, the processor 104 may be configured to calculate a Delta Torque as the difference between the filtered demand torque and the actual torque. The filtered demand torque represents a processed value of the torque requested by the driver or control system, accounting for noise suppression and transient filtering, while the actual torque corresponds to the real-time torque output of the motor as determined from the sensor measurements or control feedback. Further, by continuously computing the Delta Torque, the processor 104 enables accurate monitoring of the torque deviations that may indicate unintended acceleration, unintended deceleration, or other anomalies in the DTU operation. Beneficially, the processor 104 enables the precise and real-time detection of torque discrepancies, thereby improving the reliability of fault diagnosis in the DTU. Further, by quantifying the torque difference, the system 100 identifies the abnormal operating conditions that may not be apparent through conventional fault detection methods relying solely on sensor thresholds. Moreover, the abnormal operating conditions allow for timely initiation of appropriate safety measures, such as torque limiting, DTU shutdown, or operator alerts, thereby enhancing the vehicle safety, protecting drivetrain components from excessive stress, and maintaining optimal driving performance. Additionally, the continuous Delta Torque monitoring supports compliance with functional safety standards and facilitates predictive maintenance by identifying fault trends before critical failures occur.
In an embodiment, the processor 104 may be configured to determine a maximum allowable Delta Torque by multiplying the filtered demand torque with a calibratable factor for detecting unintended acceleration (UIA1, UIA2) and unintended deceleration (UID1, UID2), and to trigger flags when the Delta Torque exceeds the maximum allowable Delta Torque for a specified duration. The safety flags are used to initiate subsequent protective actions, such as limiting torque output, alerting the operator, or engaging other functional safety measures to ensure safe operation of the DTU. Beneficially, the processor 104 enables the precise detection of unintended torque deviations by dynamically calculating allowable torque limits based on real-time demand torque and adjustable calibration factors. As a result, the system 100 may account for varying operating conditions, driving scenarios, and vehicle configurations. The detection of the unintended torque deviations minimizes false positives in fault detection while ensuring rapid identification of genuine unintended acceleration or deceleration events. Further, by triggering safety flags only when deviations exceed defined limits for the predetermined time, the system 100 reduces the likelihood of unnecessary interventions, thereby enhancing both vehicle safety and driver comfort. Furthermore, the use of calibratable factors allows manufacturers to fine-tune detection sensitivity for different vehicle models, ensuring compliance with safety standards while optimizing performance.
In an embodiment, the processor 104 may be configured to use a functional safety state, functional safety demand torque allow, and functional safety demand torque stop flags to control a FOC system for processing the filtered demand torque. The functional safety state flag indicates the current safety mode of the DTU based on fault diagnostics, the functional safety demand torque allow flag permits the FOC system to generate torque according to filtered demand values under safe operating conditions, and the functional safety demand torque stop flag commands an immediate torque cessation in unsafe conditions. The coordinated flag-based control enables the FOC system to dynamically adjust motor torque output in response to real-time safety assessments while maintaining stable drive performance. Beneficially, the use of functional safety flags to control the FOC system enables rapid and determined transition between normal and safe operating states, ensuring that torque generation is either permitted or inhibited based on validated safety criteria. Further, by embedding safety logic directly into the FOC torque control loop, the system 100 achieves low-latency fault response without requiring complete shutdown of control processing, thereby preventing unsafe torque events such as unintended acceleration or deceleration. Furthermore, the approach maintains smooth torque delivery during allowable conditions, thereby enhancing the driver comfort while preserving vehicle performance. Overall, the system 100 ensures the compliance with functional safety standards by integrating real-time fault handling into the motor control process, thereby reducing the risk of hardware damage, prolonging component lifespan, and improving overall reliability of the system 100.
In an embodiment, the processor 104 may be configured to implement safety measures comprising one or more of: reducing power output, disabling the DTU, alerting the vehicle operator, and logging the fault condition. The safety measures implemented by the processor 104 may include reducing the power output to the motor, thereby limiting the torque generation to prevent further mechanical or electrical stress on the system components. Further, in severe fault conditions, the processor 104 disables the entire operations of the DTU to immediately halt torque production and ensure maximum safety. Additionally, the system 100 alerts the vehicle operator through visual indicators, auditory warnings, or haptic feedback, thereby enabling the operator to take prompt corrective action. Furthermore, the detected fault condition is logged in a non-volatile memory, allowing for subsequent diagnosis, root cause analysis, and maintenance planning. Moreover, the safety measures may be automatically triggered based on the detected fault severity and type, thereby ensuring timely intervention and enhancing overall system reliability.
The present disclosure provides the system 100 for fault diagnostic of the battery management system 102. The system 100 as disclosed by present disclosure provides a robust and intelligent fault diagnostic and safety control system for the DTU of the electric vehicle. Beneficially, by employing the plurality of sensors 102, the system 100 enables comprehensive detection of both electrical and electronic faults, such as undervoltage, overvoltage, overcurrent, short circuits, sensor failures, throttle malfunctions, and communication issues, as well as hardware-level and associated component failures in subsystems like the BMS, OBC, and motor systems. Further, the capability of the processor 104 to compute the demand torque, compare the filtered demand torque with the actual torque, and calculate the Delta Torque allows precise identification of unintended acceleration or deceleration events, thereby ensuring rapid and condition-specific fault detection. Furthermore, the integration of calibratable factors for determining allowable Delta Torque thresholds allows the system 100 to adapt the different vehicle configurations and the wide range of operating environments. Moreover, the use of the functional safety states and dedicated torque control flags to manage the FOC system, ensuring the torque regulation during faults is smooth, precise, and minimally disruptive to the driving experience. Subsequently, the ability to implement dynamic safety measures such as reducing power output, disabling the DTU, alerting the operator, and logging faults enhances the reliability of the system 100, thereby prevents the component damage, and facilitates root cause analysis for preventive maintenance. Overall, the system 100 improves the functional safety and operational stability of the DTU, and optimizes the vehicle performance, extends component lifespan, and supports compliance with automotive safety standards.
In an embodiment, the system 100 for fault diagnostics of the DTU of the electric vehicle. The system 100 comprising the plurality of sensors 102 and the processor 104. The plurality of sensors 102 are configured to detect the at least one fault associated with the DTU. Further, the processor 104 is configured to compute the demand torque, compare the filtered demand torque with the actual torque, and process the filtered demand torque and implement safety measures based on the detected faults and processed demand torque. Further, the plurality of sensors 102 comprises the wheel speed sensor 102a, the voltage sensor 102b, the current sensor 102c, the temperature sensor 102d, and the position sensor 102e. Furthermore, the plurality of sensors 102 are configured to detect electrical faults comprising the at least one of the DC under-voltage, the DC over-voltage, the phase over-current, the short circuits, the motor over-temperature, the position sensor failures, the throttle malfunctions, the DTU hardware malfunctions, and the communication failure comprising the at least one of I2C, CAN, and PWM. Moreover, the plurality of sensors 102 are configured to detect faults comprising the at least one of the watchdog issues, the CPU issues, the flash corruption, the MOSFET failures, the gate driver failures, the sensing circuit failures, and the faults in associated components comprising the Battery Management System (BMS), the Onboard Charger (OBC), the motor systems, the deep battery discharge, the DC voltage drop, and the signal line connection problems. Moreover, the processor 104 is configured to calculate the Delta Torque as the difference between the filtered demand torque and the actual torque. Moreover, the processor 104 is configured to determine the maximum allowable Delta Torque by multiplying the filtered demand torque with the calibratable factor for detecting unintended acceleration (UIA1, UIA2) and unintended deceleration (UID1, UID2), and to trigger flags when the Delta Torque exceeds the maximum allowable Delta Torque for the specified duration. Moreover, the processor 104 is configured to use the functional safety state, the functional safety demand torque allow, and the functional safety demand torque stop flags to control the FOC system for processing the filtered demand torque. Moreover, the processor 104 is configured to use the functional safety state, the functional safety demand torque allow, and the functional safety demand torque stop flags to control the FOC system for processing the filtered demand torque. Moreover, the processor 104 is configured to implement safety measures comprising one or more of: reducing power output, disabling the DTU, alerting the vehicle operator, and logging the fault condition.
Figure 2, describes a method 200 for fault diagnostics of a Drive Train Unit (DTU). The method 200 starts at step 202 and completes at 206. At step 202, the method 200 comprises detecting at least one fault associated with the DTU. At step 204, the method 200 comprises detecting an unintended acceleration and/or deceleration. At step 206, the method 200 comprises computing demand torque. At step 208, the method 200 processing filtered demand torque.
It would be appreciated that all the explanations and embodiments of the portable device 100 also applies mutatis-mutandis to the method 200.
In the description of the present invention, it is also to be noted that, unless otherwise explicitly specified or limited, the terms “disposed”, “mounted”, and “connected” are to be construed broadly, and may for example be fixedly connected, detachably connected, or integrally connected, either mechanically or electrically. They may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood in specific cases to those skilled in the art.
Modifications to embodiments and combination of different embodiments of the present disclosure described in the foregoing are possible without departing from the scope of the present disclosure as defined by the accompanying claims. Expressions such as “including”, “comprising”, “incorporating”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non- exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural where appropriate.
,CLAIMS:WE CLAIM:
1. A system (100) for fault diagnostics of a Drive Train Unit (DTU) of an electric vehicle, the system (100) comprising:
- a plurality of sensors (102) configured to detect at least one fault associated with the DTU; and
- a processor (104) configured to:
- compute a demand torque, compare a filtered demand torque with an actual torque, and process the filtered demand torque; and
- implement safety measures based on the detected faults and processed demand torque.
2. The system (100) as claimed in claim 1, wherein the plurality of sensors (102) comprises a wheel speed sensor (102a), a voltage sensor (102b), a current sensor (102c), a temperature sensor (102d), and a position sensor (102e).
3. The system (100) as claimed in claim 1, wherein the plurality of sensors (102) are configured to detect electrical faults comprising at least one of a DC under-voltage, a DC over-voltage, a phase over-current, a short circuits, a motor over-temperature, a position sensor failures, a throttle malfunctions, a DTU hardware malfunctions, and a communication failure comprising at least one of I2C, CAN, and PWM.
4. The system (100) as claimed in claim 1, wherein the plurality of sensors (102) are configured to detect faults comprising at least one of a watchdog issues, a CPU issues, a flash corruption, an MOSFET failures, a gate driver failures, a sensing circuit failures, and faults in associated components comprising a Battery Management System (BMS), an Onboard Charger (OBC), motor systems, a deep battery discharge, a DC voltage drop, and signal line connection problems.
5. The system (100) as claimed in claim 1, wherein the processor (104) is configured to calculate a Delta Torque as the difference between the filtered demand torque and the actual torque.
6. The system (100) as claimed in claim 5, wherein the processor (104) is configured to determine a maximum allowable Delta Torque by multiplying the filtered demand torque with a calibratable factor for detecting unintended acceleration (UIA1, UIA2) and unintended deceleration (UID1, UID2), and to trigger flags when the Delta Torque exceeds the maximum allowable Delta Torque for a specified duration.
7. The system (100) as claimed in claim 1, wherein the processor (104) is configured to use a functional safety state, functional safety demand torque allow, and functional safety demand torque stop flags to control a Field-Oriented Control (FoC) system for processing the filtered demand torque.
8. The system (100) as claimed in claim 1, wherein the processor (104) is configured to implement safety measures comprising one or more of: reducing power output, disabling the DTU, alerting the vehicle operator, and logging the fault condition.
9. A method (200) for fault diagnostics of a Drive Train Unit (DTU), the method (200) comprising:
- detecting at least one fault associated with the Drive Train Unit (DTU);
- detecting an unintended acceleration and/or deceleration;
- computing demand torque; and
- processing filtered demand torque.