Drive control unit for a vehicle for detecting faults in connections and procedures for doing so

Abstract

The DCU 102 comprises an inverter circuit 106 with pairs of semiconductor switches Q1, Q2, Q3, Q4, Q5, and Q6, which are connected in parallel and can be connected to a power supply 114. A node between each of the pairs of semiconductor switches Q1, Q2, Q3, Q4, Q5, and Q6 is internally connected to the respective terminal 108, and the inverter circuit 106 can be externally connected to a drive motor 110. The DCU 102 also comprises a controller 104, which is connected to the pairs of semiconductor switches Q1, Q2, Q3, Q4, Q5, and Q6 to control the operation of the drive motor 110, characterized in that, when the DCU 102 is in operation, the controller 104 is designed to detect a fault at the terminals 108 based on the determination and comparison of characteristic parameters with a corresponding reference value. The fault is a loose connection at terminals 108 between the drive motor 110 and the DCU 102.

Description

Field of the InventionThe present disclosure relates to a drive control unit (DCU) for a vehicle for detecting failures at ports and a method thereof.Prior ArtThere are certain techniques that judge or recognize the loose connection of a terminal based on a voltage drop in the measurement of the voltage before and after the terminal. This technique is not suitable for systems in which additional loads are connected to the terminal and can lead to voltage drops. It also depends on the accuracy of measurement of the voltage before and after the connection. Since no sensor for the voltage measurement can be attached to the controller before connection, this requires an accurate voltage indication from the energy source, i.e. the battery.According to the prior art WO20188592, arc fault detection in an engine control unit of a vehicle and a method for operating the same are disclosed. The subject matter described in the related art relates to an engine control unit configured for arc fault detection in a vehicle. The motor control unit described herein is provided with a plurality of power terminals for connection to a battery and a motor. Specifically, each power terminal of the plurality of power terminals is provided with an arc fault detection element for detecting arc faults generated therein. More specifically, the arc fault detection elements provided are thermistors disposed at the power terminals inside the motor control unit. The motor control unit thus equipped with the thermistors is adapted to shut down the vehicle due to detection of an arc fault in the power terminals by the thermistors. By disposing the arc fault detecting elements within the engine control unit, compactness of the engine control unit and the vehicle is ensured.BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGSAn embodiment of the present disclosure will be described with reference to the following accompanying drawings: FIG. 1 is a block diagram of a drive control unit (DCU) for a vehicle for detecting failures at terminals according to an embodiment of the present invention; FIG. 2 shows a first path and a second path of current flow through selected semiconductor switches and the selected phases of the drive motor according to an embodiment of the present invention; FIG. 3 shows a third path and a fourth path of current flow through selected semiconductor switches and the selected phases of the drive motor according to an embodiment of the present invention; FIG. 4 shows a fifth path and a sixth path of current flow through selected semiconductor switches and the selected phases of the drive motor according to an embodiment of the present invention; and FIG. 5 is a flow chart of a method for detecting errors at terminals of the DCU of the vehicle according to the present invention.DETAILED DESCRIPTION OF THE EMBODIMENTSFIG. 1 is a block diagram of a drive control unit (DCU) for a vehicle for detecting failures at ports according to an embodiment of the present invention. The DCU 102 includes an inverter circuit 106 including pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 (shown in FIG. 2 ) connected in parallel with each other and connectable to a power supply 114. A node between each of the pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 is internally connected to a respective terminal 108, and the inverter circuit 106 is externally connectable to a drive motor 110. The DCU 102 also includes a controller 104 connected to the pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 to control the operation of the drive motor 110, characterized in that when the DCU 102 is in operation, the controller 104 is configured to detect a fault at the terminals 108 based on the determination and comparison of characteristic parameters with a corresponding reference value.The DCU 102, also referred to as an engine control unit (MCU), is part of the electric or hybrid vehicle 100, for example, but not limited to, a two-wheeled vehicle such as a motorcycle, motorcycle, scooter, a three-wheeled vehicle such as a car bike, a four-wheeled vehicle such as cars, snowmobiles, trucks, buses, and other vehicles 100 using the DCU 102 and the drive motor 110. The controller 104 is also configured to receive signals from the current sensor 112 for each phase (e.g., U, V, W phase in a three-phase system) of the drive motor 110. The DCU 102 is shown to have five terminals, three for the phase terminals to the drive motor 110 and the remaining two as battery terminals.According to an embodiment of the present invention, the controller 104 is equipped with the necessary signal detection, detection and processing circuits. The controller 104 includes input / output interfaces with pins or ports, the memory element (not shown) such as random access memory (RAM) and / or read only memory (ROM), an analog-to-digital converter (ADC) and a digital-to-analog converter (DAC), clock, timer, counter, and at least one processor (which can implement machine learning) connected to each other and to other components via communication bus channels. Logics or instructions or programs or applications or modules / models and / or threshold values / ranges, reference values, predefined / specific criteria / conditions, maps / tables based on correction factors, which are accessed by the at least one processor according to the defined routines, are prestored in the memory element. The internal components of the controller 104, being prior art, are not explained and are not to be understood as limiting. The controller 104 may also include communication units such as transceivers to communicate via wireless or wired means such as the Global System for Mobile Communications (GSM), 3G, 4G, 5G, Wi-Fi, Bluetooth, Ethernet, serial networks, and the like. The controller 104 is implementable in the form of a system-in-package (SiP) or system-on-chip (SOC) system or other known types. Examples of the controller 104 include, but are not limited to, a microcontroller, a microprocessor, microcomputer, etc.According to an embodiment of the present invention, the fault is an arc, a high current, and / or a loose connection at the terminal 108. Further, according to an embodiment, the characteristic parameters relate to at least one parameter selected from a group comprising phase components of the stator current or the phase currents, an actual motor torque, a path resistance and a terminal temperature. The characteristic parameters relating to the phasor components of the stator current and the corresponding reference value are at least one selectable from a group comprising: a cumulative deviation in at least one phasor component of the stator current with a first deviation threshold, a number of deviations in the at least one phasor component of the stator current with a first threshold number, a rate of change of the at least one phasor component of the stator current with a first threshold rate, and a deviation in magnitude and / or frequency on fast Fourier transform (FFT) values of the measured phase current or the at least one phasor component of the stator current with a first reference FFT value. The characteristic parameters relating to the actual motor torque and the corresponding reference value are at least one selected from a group comprising: a cumulative deviation of the actual motor torque from a second deviation threshold, a number of deviations of the actual motor torque with a second threshold number, a deviation of the rate of change of the actual motor torque with a second threshold rate, and a deviation in the magnitude and / or frequency of the fast Fourier transform (FFT) values of the actual motor torque with a second reference FFT value. The resistance of the paths is at least one resistance of predetermined current flow paths that is compared to the respective threshold resistance value. The connection temperature is compared with the reference temperature.According to an embodiment of the present invention and for determining an error using at least one phasor component of the stator current as a characteristic parameter, the controller 104 is configured to measure the stator current by the respective current sensor 112, to calculate at least one phasor component of the stator current using the measured stator current, to determine the characteristic parameter relating to the at least one phasor component of the stator current, to compare the characteristic parameter with the respective reference value and to detect an error based on the result of the comparison. The phasor component of the stator current includes a direct axis current (I d) and a quadrature axis current (I q), as are known in the art.According to the present invention, a function of the DCU 102 will be explained with the phasor component of the stator current as a characteristic parameter. Assume that the stator current is measured with the current sensor 112. The controller 104 derives the current I d and I q from the measured stator current and rotor position. The controller 104 monitors the deviation of the phasor components or derived I d- and I q- currents from the reference deviation and records them at regular intervals. The time interval is configurable. Whenever the deviation is observed, the deviation is cumulatively added, and when it is detected that the cumulative deviation exceeds the first deviation threshold value, the controller 104 identifies the error or detects the error and stores it in the storage element. This is displayed to a user of the vehicle 100 by display means such as display, audio, haptics, light, etc. on the cluster unit or infotainment unit. Alternatively, if the number of variations in the phasor components exceeds the respective first threshold number, the controller 104 again identifies an error and stores it in the storage element. In yet another alternative, if there is a variation in the rate of change of the phasor components or the inferred I d- and I q- currents from the absolute value based on engine speed and from the reference rate of change of the I d- and I q- currents dynamically selected based on the operating point, the controller 104 detects an error and stores it in the storage element. In yet another alternative, the controller 104 performs an FFT of the current phasor currents and / or the phasor components (derived from I d and I q ) of the stator currents. If the magnitude and / or frequency of the FFT values deviate from the corresponding first reference FFT values, the controller 104 in turn recognizes this as an error and stores it in the memory element. The controller 104 is configurable to account for at least one characteristic parameter relating to the phasor components (derived from I d and I q ) of the stator current, i.e. either independently of each other or in combination.According to an embodiment of the present invention, the controller 104 is configured to measure variables including current through each phase of the drive motor 110, phase voltage, direct current (DC current), direct current (DC voltage), rotor speed, rotor position, and motor design parameters such as winding resistance and inductance, using the characteristic parameter related to actual motor torque, to determine the error. The controller 104 further calculates the actual engine torque as a function of the measured variables. The controller 104 is further configured to compare the characteristic parameter related to the actual motor torque with the respective reference value and determine the error using the result of the comparison.In a working scenario, when the vehicle 100 is driven by the driver, the controller 104 monitors the variables and calculates the actual engine torque. For example, the controller 104 compares the deviation from the cumulative actual motor torque to the second deviation threshold, or the number of deviations from the actual motor torque to the second threshold number, or the deviation from the rate of change of the actual motor torque to the second threshold rate, and if there is a deviation, the controller 104 detects an error at the terminal 108 and stores it in the storage element. The controller 104 also performs an FFT on the actual engine torque and compares the magnitude and / or frequency of the FFT values to second reference FFT values to detect the error. If there is a deviation, the controller 104 detects the error and stores it in the storage element.According to one embodiment of the present invention, the drive control unit (DCU) for the vehicle 100 is disclosed for detecting faults at the ports 108. The DCU 102 includes the inverter circuit 106 including pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 (shown in FIG. 2 ) connected in parallel with each other and connectable to a power supply 114. The node between each of the pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 is internally connected to a respective terminal 108, and the inverter circuit 106 is externally connectable to the drive motor 110. The DCU 102 also includes the controller 104 connected to the pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 to control operation of the drive motor 110, characterized in that the temperature sensors 116 for each terminal 108 can be connected to at least one input pin / port of the controller 104 via the comparator 118. Thus, in the event of a lack of input pins / ports, a single input pin / port may be configured to receive a single signal from all temperature sensors. For example, in a three phase system, three temperature sensors 116 may be connected to the single input pin / port via comparator 118.According to an embodiment of the present invention, the temperature sensor 116 is provided for the battery terminals, and the controller 104 is configured to measure the temperature of the battery terminal via the comparator or directly and compare it with the threshold temperature to detect the fault, in particular a loose connection at the battery terminals.According to an embodiment of the present invention, for determining the fault using the terminal temperature as a characteristic parameter, the controller 104 is connected via a comparator 118 to temperature sensors 116 for each terminal 108 and is configured to receive a signal from the comparator 118. The signal includes the difference in the temperatures measured by the individual temperature sensors 116. The controller 104 is configured to compare the signal to a temperature threshold and detect the fault based on the result of the comparison.According to an embodiment of the present invention, in order to determine an error using the path resistance as a characteristic parameter, the controller 104 is configured to control the ON / OFF states of the semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 in at least one predetermined path to achieve a current flow path(s) corresponding to(s) predetermined(s). The controller 104 is then configured to calculate the path resistance based on the applied voltage and the current measured by the current sensor 112 for each of the at least one predetermined path. The controller 104 is further configured to compare the path resistance with a corresponding reference resistance as a reference value. The controller 104 then determines the error from the result of the comparison. If the resistance of the path is greater than the reference resistance, the fault is detected. The controller 104 is either configured to detect the resistance of all paths and then make a comparison with the respective reference resistance, or at least one of the resistors. The various flow path sequences are shown in FIGS. 2 to 4.FIG. 2 shows a first path and a second path of current flow through selected semiconductor switches and the selected phases of the drive motor according to an embodiment of the present invention. In the first path 200, the semiconductor switches Q 1 and Q 4 are turned ON and other semiconductor switches are turned OFF, and connected via the U and V phases of the driving motor 110. The first path 200 is shown with the dashed line between two terminals of the power supply 114. Further, the controller 104 controls the state of the semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 by a pulse width modulation (PWM) signal 202.Also shown in FIG. 2 is the second path 210. Here, the semiconductor switches Q 1 and Q 6 are turned on by the U and W phases of the driving motor 110.FIG. 3 shows a third path and a fourth path of current flow through selected semiconductor switches and the selected phases of the drive motor according to an embodiment of the present invention. The third path 300 includes the activated semiconductor switches Q 3 and Q 6 through the V and W phases of the drive motor 110. Similarly, the fourth path 310 includes the activated semiconductor switches Q 3 and Q 2 through the V and U phases of the drive motor 110. The current direction, as shown by the dashed line in FIG. 3, must be taken into account.FIG. 4 shows a fifth path and a sixth path of current flow through selected semiconductor switches and the selected phases of the drive motor according to an embodiment of the present invention. The fifth path 400 includes current flow through the semiconductor switch Q 5, the W-phase, the U-phase, and the semiconductor switch Q 2. This is indicated by the dashed arrow. Similarly, the sixth path 410 includes current flow through the semiconductor switch Q 5, the W-phase, the V-phase, and the semiconductor switch Q 4. This is indicated by the dashed arrow.In FIGS. 2 to 4, the controller 104 calculates the resistance of the first path 200, the second path 210, the third path 300, the fourth path 310, the fifth path 400, and / or the sixth path 410 either sequentially or randomly. The semiconductor switches are controlled with the PWM signal 202. The controller 104 calculates the resistance until the fault is found. Alternatively, the controller 104 is configured to measure the resistance for all paths regardless of whether or not a fault is found. The resistance is calculated based on the voltage divided by the current. The voltage is detected from the applied voltage, and the current is measured with the current sensor 112. If there is a deviation, the controller 104 detects the error and stores it in the storage element. The fault is displayed in the vehicle 100, as mentioned above.FIG. 5 is a flow chart of a method for detecting errors at terminals of the DCU of the vehicle according to the present invention. The fault is detected when the DCU 102 is operated in conjunction with the drive motor 110. The DCU 102 includes pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 connected in parallel with each other and connectable to a power supply 114. The node between each of the pairs of semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 is internally connected to the terminals 108, and the terminals 108 are externally connectable to the drive motor 110. The method is characterized by a plurality of steps, of which a step 502 comprises the determination of values of characteristic parameters by the controller 104. A step 504 includes comparing, by the controller 104, values of the determined characteristic parameter with corresponding reference values. A step 506 includes detecting, by the controller 104, the fault at the terminals 108 based on the result of the comparison.According to the method of the present invention, the fault is at least one of arc, high current, and loose connection at the terminal 108. Further, the characteristic parameters refer to at least one parameter selected from the group consisting of the phase components of the stator current, the actual motor torque, the resistance of at least one current flow path, and the terminal temperature. The characteristic parameters relating to the phasor components of the stator current and the corresponding reference value are at least one selected from the group comprising: the cumulative deviation in at least one phasor component of the stator current with the first deviation threshold, the number of deviations in the at least one phasor component of the stator current with the first threshold number, the rate of change of the at least one phasor component of the stator current with the first threshold rate, and the deviation in magnitude and / or frequency on fast Fourier transform (FFT) values of phase currents or the at least one phasor component of the stator current with the first reference FFT values. The characteristic parameters relating to the actual motor torque and the corresponding reference value are at least one selected from the group comprising: the cumulative deviation of the actual motor torque from the second deviation threshold, the number of deviations of the actual motor torque with the second threshold number, the deviation of the rate of change of the actual motor torque with the second threshold rate, and the deviation in the magnitude and / or frequency of the fast Fourier transform (FFT) values of the actual motor torque with the second reference FFT value. The resistance of the paths is at least one resistance of predetermined current flow paths that is compared to the respective threshold resistance value. The connection temperature is compared with the reference temperature.According to step 502, a method for determining the at least one phasor component of the stator current as the characteristic parameter is provided. The method comprises a plurality of steps, of which a step 508 comprises measuring the stator current through the respective current sensor 112. A step 510 includes calculating at least one phasor component of the stator current using the measured stator current. A step 512 includes determining a characteristic parameter relating to the at least one phasor component of the stator current.According to step 502, a method for determining the actual motor torque as the characteristic parameter is provided. The method includes a step 514 that includes measuring, by the controller 104, variables that include current through each phase of the motor, phase voltage, direct current (DC current), direct current (DC voltage), rotor speed, rotor position, and motor design parameters such as winding resistance and inductance. A step 516 includes, by the controller 104, calculating the actual engine torque as a function of the measured variables. The torque deviation is observed by the method. The controller 104 detects torque deviations arising from unbalanced phase currents as a function of increased resistance of the terminal 108. The torque deviation may also be affected due to a change in winding resistance. To isolate the effects due to the change in winding resistance, the method includes detecting the magnitude of the torque offset and comparing it to the reference value.According to step 502, a method for measuring terminal temperatures is provided. The method includes a step 518 including receiving, at an input pin / port of the controller 104, the signal from the comparator 118 connected to temperature sensors 116 for each terminal 108. The measured temperatures are compared and the difference is received as input for further processing by the controller 104. In the method, a temperature rise of the terminals 108 is monitored. First, the values of the temperature sensors 116 are checked for plausibility by comparing with other sensor values. Then, the controller 104 checks for an increase in temperature or the absolute temperature, and if one of them is higher than the temperature threshold, the controller 104 recognizes that the terminal 108 has a high resistance, which may be due to one of the causes of a failure. After detection, the terminals 108 may be checked for a loose connection or contaminants in the contact surface may be removed. The temperature is measured by attaching temperature sensors 116 to each of the terminals 108 within the DCU 102 and monitored throughout operation of the DCU 102. Since the temperature sensor 116 of each port 108 requires an analog input for monitoring, this is optimized with a corresponding comparator 118 and multiplexer if there are not enough analog pins in the controller 104 or otherwise available.According to one embodiment of the present invention, heating of the terminals 108 can be detected on the basis of the current flow, said heating confirming / validating an abnormal temperature rise. This occurs at three different current intensities (low, medium and high) to have individual detection thresholds for three levels. The square of current over time is used to determine the amount of energy flow into the traction motor 110 and to prevent it from being overheated by excessive currents during vehicle use. The value of the square current over time indicates whether the temperature rise is due to abnormal heating or to the use of the vehicle.According to step 502, a method for determining the resistance of the flow paths as the characteristic parameter is provided. The method includes a step 520 including controlling, by the controller 104, the ON / OFF states of the semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 in at least one of a plurality of predetermined paths. A step 522 includes calculating, by the controller 104, the resistance based on the applied voltage and the measured current by the current sensor 112 for each path. The resistance of the current flow path is measured by selectively switching semiconductor switches (such as MOSFETs or FETs, etc.) and compared to the reference resistance value. Before comparing, each of the resistance values is checked for its plausibility by comparing it with the resistance of other resistance values. Any change in the estimated resistance from the reference resistance is considered inadequate. Based on the magnitude of the change in resistance, the method or controller 104 detects and recognizes the fault.According to an embodiment of the present invention, the DCU 102 and method for detecting terminal failures (such as loose connection) are provided by characteristic parameters including temperature sensing, torque offset testing, phase current and phase components of stator current and path resistance. The present invention provides a solution for detecting a loose connection of the power terminals 108 to the DCU 102, i.e., the DC power terminals 108 and the phase terminals, detecting a temperature rise at the terminals 108 due to an increased contact resistance caused by a loose connection, and detecting a change in resistance of the current flow path between the terminals 108 by selectively switching semiconductor switches Q 1, Q 2, Q 3, Q 4, Q 5, and Q 6 such as MOSFETs. The present invention allows for early detection of loose connections of terminals 108 and other failures. The characteristic parameters taken into account by the DCU 102 use available / present sensors in the drive motor 110, no additional / external sensors are provided / needed. The characteristic parameters may be used either alone or in conjunction with each other to ensure robustness.It is to be understood that embodiments described in the foregoing description are for illustrative purposes only and do not limit the scope of the present invention. Numerous such embodiments and other modifications and alterations of the embodiment described in the specification are provided. The scope of the invention is limited solely by the scope of the claims.References included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedWO20188592

[0003]

Claims

A drive control unit (DCU) (102) for a vehicle (100) for detecting faults on terminals (108), the DCU (102) comprising: an inverter circuit (106) comprising pairs of semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6) connected in parallel to each other and connectable to a power supply, a node between each of the pairs of semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6) being internally connected to a respective terminal (108), the inverter circuit (106) being externally connectable to a drive motor (110), and a controller (104) connected to the pairs of semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6), To control the operation of the drive motor (110), characterized in that when the DCU (102) is operating, the controller (104) is configured to detect a fault at the terminals (108) based on the determination and comparison of characteristic parameters with a corresponding reference value.The DCU (104) of claim 1, wherein the fault is at least one of an arc, a high current, and a loose connection at the terminals (108), and wherein the characteristic parameters relate to at least one parameter selected from a group comprising phase current or phasor components of the stator current, an actual motor torque, a resistance of the flux path, and a terminal temperature, wherein the characteristic parameters relating to the phasor components of the stator current and the corresponding reference value are at least one selected from a group comprising: a cumulative deviation in at least one phasor component of the stator current with a first deviation threshold, a number of deviations in the at least one phasor component of the stator current with a first threshold number, a rate of change of the at least one phasor component of the stator current having a first threshold rate and a variation in magnitude and / or frequency to fast Fourier transform (FFT) values of the phase current or the at least one phasor component of the stator current having a first reference FFT value, wherein the characteristic parameters relating to the actual motor torque and the corresponding reference value are at least one selected from a group comprising: a cumulative variation of the actual motor torque from a second variation threshold, a number of variations of the actual motor torque with a second threshold number, a variation in the rate of change of the actual motor torque at a second threshold rate and a variation in the magnitude and / or frequency of the fast Fourier transform (FFT) values of the actual motor torque at a second reference FFT value, wherein the resistance of the flow paths is at least one resistance of a predetermined sequence of current flow paths that is compared to the respective threshold resistance.The DCU (102) of claim 2, wherein to determine an error using at least one phasor component of the stator current as a characteristic parameter, the controller (104) is configured to measure the stator current by the respective current sensor (112); calculate at least one phasor component of the stator current using the measured stator current; determine a characteristic parameter relating to the calculated at least one phasor component of the stator current; compare the characteristic parameter with the respective reference value and detect an error based on the result of this comparison.The DCU (102) of claim 2, wherein the determination of the fault is made using the characteristic parameter related to the actual motor torque, wherein the controller (104) is configured to measure variables including current through each phase of the drive motor, the phase voltage, the direct current (DC), the direct current (DC), the rotor speed, the rotor position, and motor design parameters such as the winding resistance; calculate the actual motor torque as a function of measured phase current, phase voltage, direct current (DC), direct current (DC), rotor speed, rotor position, and motor design parameters such as the winding resistance; compare the characteristic parameter related to the actual motor torque with the respective reference value; and determine the fault using the result of the comparison.The DCU (102) of claim 2, wherein to determine the fault using the terminal temperature as a characteristic parameter, the controller (104) is connected via a comparator (118) to temperature sensors (116) for each terminal (108) and is configured to receive a signal from the comparator (118), the signal comprising the difference of the temperatures measured by the individual temperature sensors (116); compare the signal to a temperature threshold; and determine a fault based on the result of this comparison.The DCU (102) according to claim 2, wherein in order to determine an error using the resistance of the paths as a characteristic parameter, the controller (104) is configured to control the ON / OFF states of the semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6) in at least one predetermined path; calculate the path resistance based on the applied voltage and the current measured by a current sensor (112) for each of the at least one predetermined paths; compare the path resistance with a reference resistance as a reference value; and determine an error using the result of the comparison.A method of detecting faults at terminals (108) of a drive control unit (DCU) (102) when operating in conjunction with a drive motor (110), the DCU (102) comprising pairs of semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6) connected in parallel to each other and connectable to a power supply, a node between each of the pairs of semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6) being internally connected to the terminals (108), the terminals (108) being externally connectable to a drive motor (110), characterised in that the method comprises the steps of: determining the values of characteristic parameters; comparing the values of the determined characteristic parameters with the respective reference values and detecting a fault at the terminals (108) based on the result of the comparison.The method of claim 6, wherein the fault is at least one of an arc, a high current, and a loose connection at the terminals (108), and wherein the characteristic parameters relate to at least one parameter selected from a group comprising phase current or phasor components of the stator current, an actual motor torque, a resistance of paths, and a terminal temperature, wherein the characteristic parameters relating to the phasor components of the stator current and the corresponding reference value are at least one selected from a group comprising: a cumulative deviation in at least one phasor component of the stator current with a first deviation threshold, a number of deviations in the at least one phasor component of the stator current with a first threshold number, a rate of change of the at least one phasor component of the stator current having a first threshold rate and a variation in magnitude and / or frequency to fast Fourier transform (FFT) values of the phase current or the at least one phasor component of the stator current having a first reference FFT value, wherein the characteristic parameters relating to the actual motor torque and the corresponding reference value are at least one selected from a group comprising: a cumulative variation of the actual motor torque from a second variation threshold, a number of variations of the actual motor torque with a second threshold number, a variation in the rate of change of the actual motor torque at a second threshold rate and a variation in the magnitude and / or frequency of the fast Fourier transform (FFT) values of the actual motor torque at a second reference FFT value, wherein the path resistance is at least one resistance of a predetermined current flow path that is compared to the respective threshold resistance.The method of claim 7, wherein to determine the at least one phasor component of the stator current as the characteristic parameter, the method comprises the steps of: measuring the stator current by the respective current sensor (112); calculating at least one phasor component of the stator current using the measured stator current; and determining a characteristic parameter relating to the at least one phasor component of the stator current.The method of claim 7, wherein to determine the actual motor torque as the characteristic parameter, the method comprises the steps of: measuring variables comprising current through each phase of the drive motor (110), phase voltage, direct current (DC), direct current (DC), rotor speed, rotor position and motor design parameters such as winding resistance; and calculating the actual motor torque as a function of measured phase current, phase voltage, direct current (DC), direct current (DC), rotor speed, rotor position and motor design parameters such as winding resistance.The method of claim 7, wherein to measure port temperatures, the method comprises receiving, at an input pin / port of the controller (104), a signal from a comparator (118) connected to temperature sensors (116) for each port (108), wherein the measured temperatures are compared to each other and the difference is received as an input from the controller (104).The method according to claim 7, wherein to determine the path resistance as the characteristic parameter, the method comprises the steps of: controlling the ON / OFF states of the semiconductor switches (Q1, Q2, Q3, Q4, Q5, Q6) in at least one predetermined path; and calculating the terminal resistance based on the applied voltage and the current measured by the current sensor (112) for each predetermined path.

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