Failsafe system and method for managing failure of high power DC-DC converter of an electric vehicle

Abstract

The present disclosure relates to a failsafe system (100) and an associated method for managing failure of high power DC-DC converter of an electric vehicle. The failsafe system (100) includes a master battery management system (BMS) (102), a slave BMS (104) and a body control unit (BCU). The master BMS (102) comprises a BMS controller (102-1) that receives failure signal from a vehicle control unit (VCU) (124) on account of failure of a high power DC-DC converter (110) and accordingly activates a low power DC-DC converter (102-4) in order to power the essential loads (116) connected with the high power DC-DC converter (110). Simultaneously, the BCU optimizes functioning of non-essential loads for ensuring efficient management of power. In this manner, the electric vehicle obtains sufficient power to be able to be driven to a nearest service station for a checkup.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to an improvement in functional safety of anelectric vehicle during DC-DC failure. In particular, the present invention relates todevelopment and design of a failsafe system and an associated method to extend drivablerange of the electric vehicle during failure of a high power Direct Current (DC)-Direct Current(DC) converter.BACKGROUND

[0002] Electric vehicle, being a next generation mode of transport is continuouslyupgrading in terms of features keeping in mind the various hustles one may face whiledriving on the road. One such hustle is sudden power failure of the electric vehicle thatneeds an immediate attention such that the vehicle can be driven to the nearest servicestation (SS) to solve the issue.

[0003] Typically, an electric vehicle utilizes a large traction battery pack to power anelectric motor as required for running of the electric vehicle. The traction battery packcomprises of lithium ion (Li-ion) battery cells along with a battery management system(BMS) for efficiently monitoring the functioning and other parameters of the Li-ion batterycells. Additionally, it is well known that during starting, the electric vehicle gathers an initialpower from an auxiliary battery and therefore there is a pressing need that the auxiliarybattery needs to get charged from beforehand using suitable measures.

[0004] However, if the electric vehicle witnesses a direct current (DC) - direct current(DC) failure, the vehicle does not remain in a state of driving further. Similarly, if the DC-DCfailure is observed while the electric vehicle is in motion, the vehicle comes to a halt withina very short span of time. Therefore, the vehicle could not be taken to a service station (SS)as well for a checkup under both the conditions. This is due to the fact that during DC-DCfailure, the auxiliary battery is discharged quickly by auxiliary loads and there is not enoughbackup energy to support driving of the vehicle, even to a nearby SS.

[0005] Now, auxiliary loads (i.e. essential and non-essential loads) supported by theauxiliary battery are normally a secondary requirement and one can drive without them atleast in emergency situations. Also, in order to drive the electric vehicle to the nearest SSon account of DC-DC failure, a considerable amount of power or energy is required tooperate essential loads and these requirements can be met by optimization of functioningof non-essential loads of the vehicle that are merely the secondary requirement.

[0006] Towards this direction, the present disclosure focuses on design anddevelopment of a failsafe system in order to extend the drivable range with minimalconsumption of power or energy such that the vehicle can be smoothly taken to the nearestSS for checkup and repair.OBJECTS OF THE INVENTION

[0007] Some of the objects of the present disclosure, which at least one embodimentherein satisfy, are listed herein below.

[0008] It is an object of the present subject matter to overcome the aforementioned andother drawbacks existing in the prior art systems and methods.

[0009] It is a significant object of the present disclosure to provide a failsafe systemand an associated method in order to enhance the drivable range during failure of a highpower Direct Current (DC)-Direct Current (DC) failure during running of an electric vehicle.

[0010] It is another principal object of the present disclosure to provide a failsafesystem where all the essential loads as required for running of the electric vehicle during anemergency situation are supported.

[0011] It is even another principal object of the present disclosure to provide a failsafesystem capable of reduction of auxiliary loads acting on an auxiliary battery in order to gainan additional drivable time during failure of the high power Direct Current (DC)-DirectCurrent (DC) converter of the electric vehicle.

[0012] It is yet another object of the present disclosure to provide a failsafe systemcapable of optimizing functions of the non-essential loads in order to avoid quick dischargeof conventional low voltage battery.

[0013] It is another object of the present disclosure to provide a failsafe system thatcan operate with low power consumption.

[0014] These and other objects and advantages of the present subject matter will beapparent to a person skilled in the art after consideration of the following detailed descriptiontaking into consideration with accompanied drawings in which preferred embodiments ofthe present subject matter are illustrated.SUMMARY OF THE INVENTION

[0015] This summary is provided to introduce concepts related to development anddesign of a failsafe system and an associated method to increase drivable range of theelectric vehicle upon failure of a high power Direct Current (DC)-Direct Current (DC)converter and other emergency situation so that the vehicle can be driven to a nearestservice station. The concepts are further described below in the detailed description. Thissummary is not intended to identify key features or essential features of the claimed subjectmatter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0016] According to an embodiment of a present disclosure, there is provided a failsafesystem to manage a high power Direct Current - Direct Current (DC-DC) converter in anelectric vehicle. The system comprises of a master battery management system (BMS)having a BMS controller to receive failure signal from a vehicle control unit (VCU) regardingfailure of the high power DC-DC converter, and a low power DC-DC converter activated bythe BMS controller in response to the receipt of the failure signal to enable the low powerDC-DC converter to establish a power supply connection with essential loads which wereconnected to the high power DC-DC converter, a slave BMS communicatively coupled tothe master BMS to monitor the temperature and voltage of a plurality of cells present in abattery pack of the electric vehicle. A body control unit (BCU) or other controllers tosimultaneously receive the failure signal from the VCU for optimizing the functioning of anon-essential loads, which is / were connected to the high power DC-DC converter, basedon operating and surrounding conditions of the vehicle. In an example, other controllersmay include a programmable logic controller (PLC), a battery management system (BMS)controller, engine control unit (ECU), controllers used to monitor air conditioner, powerwindows, braking, headlights, steering, etc.

[0017] In an aspect, in the system, the BMS comprises a decision module that closesa relay to establish a power supply connection of the low power DC-DC converter with theessential loads which were connected to the high power DC-DC converter.

[0018] In an aspect, in the system, the essential loads include a multitude of controllers,a multitude of sensors, and a multitude of safety critical devices.

[0019] In an aspect, in the system, the non-essential loads include a Head Up Display(HUD), an audio accessory outlet, a sunroof, a seat heating, and a plurality of ventilationlights.

[0020] In an aspect, in the system, the other non-essential loads include a head lamp,a radiator fan, air conditioner blower, defogger, and battery pack and other powertraincomponent thermal system.

[0021] In an aspect, there is provided a method for operating a failsafe systemmanaging the failure of a high power Direct Current - Direct Current (DC-DC) converter inan electric vehicle. The method comprises simultaneously transmitting, by a vehicle controlunit (VCU), a failure alert regarding the failure of the high power DC-DC converter, to abattery management system (BMS) controller and a body control unit (BCU); activating, bythe BMS controller, a low power DC-DC converter to establish a power supply connectionwith the essential loads which were connected to the high power DC-DC convertor;establishing communication, by the BMS controller, with a slave BMS to vary predefinedtemperature and voltage of a plurality of cells present inside a battery pack of the electricvehicle; simultaneously optimizing, by the BCU, the functioning of non-essential loads,which were connected to the high power DC-DC converter, based on operating andsurrounding conditions of the vehicle; and activating, by the VCU, an alert mechanismindicating an issue with the vehicle and prompting a user with a navigation system to initiatenavigation of the vehicle to the nearest service station (SS).

[0022] In an aspect, according to the method, the activating the alert mechanismcomprises generating an alert indication in a user infotainment system regarding a powersource failure; initiating the navigation system representing a global position system (GPS)location of a plurality of service stations from the vehicle; and generating output of anestimate of the drivable range based on the optimization of the essential and non-essentialloads which were connected to the high power DC-DC converter.

[0023] In an aspect, the method further comprises of intimating the selected servicestation (SS) when the user initiates the navigation to a selected service station.

[0024] To further understand the characteristics and technical contents of the presentsubject matter, a description relating thereto will be made with reference to theaccompanying drawings. However, the drawings are illustrative only but not used to limitthe scope of the present subject matter.

[0025] Various objects, features, aspects, and advantages of the inventive subjectmatter will become more apparent from the following detailed description of preferredembodiments, along with the accompanying drawing figures in which numerals representlike components.BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING(S)

[0026] It is to be noted, however, that the appended drawings illustrate only typicalembodiments of the present subject matter and are therefore not to be considered forlimiting of its scope, for the invention may admit to other equally effective embodiments.The detailed description is described with reference to the accompanying figures. In thefigures, a reference number identifies the figure in which the reference number first appears.The same numbers are used throughout the figures to reference like features andcomponents. Some embodiments of system or methods or structure in accordance withembodiments of the present subject matter are now described, by way of example, and withreference to the accompanying figures, in which

[0027] FIG. 1 represents an architectural layout of an electric vehicle comprising of atraction battery pack along with an auxiliary battery and a load in accordance with anembodiment of the present disclosure;

[0028] FIG. 2 represents an exemplary flow diagram followed for operation of thefailsafe system in accordance with an exemplary embodiment of the present disclosure; and

[0029] FIG. 3 represents an exemplary method associated with operation of the failsafesystem in accordance with an exemplary embodiment of the present disclosure.

[0030] The figures depict embodiments of the present subject matter for the purposesof illustration only. A person skilled in the art will easily recognize from the followingdescription that alternative embodiments of the structures and methods illustrated hereinmay be employed without departing from the principles of the disclosure described herein.DETAILED DESCRIPTION

[0031] The following is a detailed description of embodiments of the disclosuredepicted in the accompanying drawings. The embodiments are in such detail as to clearlycommunicate the disclosure. However, the amount of detail offered is not intended to limitthe anticipated variations of embodiments; on the contrary, the intention is to cover allmodifications, equivalents, and alternatives falling within the spirit and scope of the presentdisclosure as defined by the appended claims.

[0032] While the embodiments of the disclosure are subject to various modificationsand alternative forms, specific embodiment thereof have been shown by way of example inthe figures and will be described below. It should be understood, however, that it is notintended to limit the disclosure to the particular forms disclosed, but on the contrary, thedisclosure is to cover all modifications, equivalents, and alternative falling within the scopeof the disclosure.

[0033] The terms "comprises", "comprising", or any other variations thereof used in thedisclosure, are intended to cover a non-exclusive inclusion, such that a device, system,assembly that comprises a list of components does not include only those components butmay include other components not expressly listed or inherent to such system, or assembly,or device. In other words, one or more elements in a system or device proceeded by"comprises… a" does not, without more constraints, preclude the existence of otherelements or additional elements in the system or device.Non-limiting Definitions

[0034] In the disclosure hereinafter, one or more terms are used to describevarious aspects of the present disclosure. For a better understanding of the presentdisclosure, a few definitions are provided herein for better understating of thepresent disclosure.

[0035] "Essential loads" can be defined as a plurality of primary loads that are inevitablyrequired for driving of an electric vehicle. These include a multitude of controllers, amultitude of sensors and a multitude of safety critical devices associated with the vehicle.

[0036] "Non-essential loads" can be defined as a plurality of secondary loads that arenot significant in nature and may not be required for driving of the electric vehicle during anemergency situation like power failure. The "non-essential loads" may include a Head UpDisplay (HUD), an audio accessory outlet, a sunroof, a seat heating and a plurality ofventilation lights that are normally not required for driving the electric vehicle underemergency conditions and head lamps, a radiator fan, an air conditioner blower and batterypack and other powertrain components thermal system. The requirement of non-essentialloads is primarily determined by operating and surrounding conditions of the vehicle likeconditions of road, time of day, for cooling requirement of the component and cabin of thecar, etc.

[0037] The present disclosure proposes a failsafe system (100) and an associatedmethod to extend drivable range of an electric vehicle on account of failure of the high powerDC-DC converter of the electric vehicle. The extension of drivable range is proposed byimplementation of a low power DC-DC converter. The low power DC-DC converter isactivated on account of failure of the high power DC-DC converter in addition to Jump startthe vehicle in existing arrangement. The low power DC-DC converter provides power toessential loads that plays a significant role in driving the electric vehicle to the nearestservice station smoothly. Further, the failsafe system (100) also allows optimization of thenon-essential loads as per surrounding conditions, which in turn saves power to aconsiderable extent. The optimization of non-essential loads, therefore, also plays a pivotalrole in extending drivable range of the electric vehicle to the nearest service station (SS).Exemplary Implementations / Embodiments

[0038] Referring to FIG. 1, there is provided an architectural layout of the electricvehicle. It may be observed from FIG. 1, that the architectural layout comprises of a tractionbattery pack, an auxiliary load (114), an auxiliary battery (112), a power electronic module(108), a high power DC-DC converter (110), essential loads (116), an USB or wirelessadapter (122) and a multitude of switches.

[0039] In an aspect, the traction battery pack includes a master battery managementsystem (BMS) (102) and a slave BMS (104). The master BMS (102) includes a BMScontroller (102-1), a decision unit (102-2), a relay (102-3) and a low power DC-DC converter(102-4).

[0040] In an aspect, the BMS controller (102-1) activates the low power DC-DCconverter (102-4) in response to the receipt of a failure signal from a vehicle control unit(VCU) (124) denoting failure of the high power DC-DC converter (110) during running of theelectric vehicle. The low power DC-DC converter (102-4) establishes a power supplyconnection with essential loads (116) which were initially connected to the high power DCDCconverter (110). Herein, in order to support the essential loads, the low power DC-DCconverter (102-4) is connected to the auxiliary battery (112) by means of an automatic ormanual switch or a combination of diode with a relay connected in parallel in such a mannerso as to power up only the essential loads (116) and not the non-essential loads (114).

[0041] In an aspect, the decision unit (102-2) receives input from the BMS controller(102-1) and in turn activates the low power DC-DC converter (102-4) by closing the relay(102-3) connected across the decision unit (102-2).

[0042] In an aspect, the slave BMS (104) is coupled to the master BMS(102) via a communicating link. The slave BMS (104) includes a high voltage analog frontend (HVAFE) and a low voltage (LV) supply of approximately similar to auxiliary batteryvoltage. Herein, the HVAFE comprises of a comparator device that is continuouslymonitoring temperature of each cell in the traction battery pack and accordingly generatesalarming signal for under voltage (UV) / over voltage (OV) condition. Herein, the HVAFE andthe LV are separated by an isolation that may be galvanic or optical or magnetic as well.

[0043] In an aspect, the primary function of the slave BMS (104) is to monitortemperature and voltage of a plurality of cells present in a battery pack of the electric vehicle.

[0044] In an aspect, the BCU also receives failure signal from the VCU (124)simultaneously as that received by the BMS controller (102-1). Further upon reception ofthe failure signal, the BCU optimizes functioning of non-essential loads based on operatingand surrounding conditions of the vehicle. These non-essential loads were also linked tothe high power DC-DC converter (110).

[0045] In an aspect, apart from the components mentioned above, the architecturallayout of the electric vehicle comprises of several other switching connections in order toestablish suitable communication among the elements.

[0046] FIG. 2 represents an exemplary flow of operations performed by the failsafesystem (100) in accordance with an exemplary embodiment of the present disclosure. In anaspect, when the vehicle is in EV READY mode, upon occurrence of failure of the highpower DC-DC converter (110), the VCU (124), being the central functioning unit of theelectric vehicle sends power source failure signals to the BMS controller (102-1) and theBCU simultaneously.

[0047] In an aspect, after receiving the failure alert, the BMS controller (102-1)activates the low power DC-DC converter (102-4) through the decision module (102-2)connected across the BMS controller (102-1). The decision module (102-2) upon receivingstatus of voltage and temperature from the slave BMS (104) and control signal from theBMS controller (102-1) activates the low power DC-DC converter (102-4) by closing therelay (102-3). In this context, it is to be mentioned that the low power DC-DC converter(102-4) turns ON after activation request by the BMS controller (102-1) only if voltage of thetraction battery remains within a predefined range and no UV / OV and under temperature(UT) / over temperature (OT) alarm signals are present.

[0048] In an aspect, activation of the low power DC-DC converter (102-4) activates thelow voltage (LV) lines across the circuit thereby supporting all the essential loads asrequired during running of the electric vehicle to a nearest service station (SS).

[0049] In this context, it is hereby mentioned that the primary objective of activating thelow power DC-DC converter (102-4) is to ensure that a minimal power which is required foroperation of the electric vehicle. In view of this, the BMS controller (102-1) also increasesthe regulation temperature of battery pack and other powertrain components in order toreduce power consumption by pumps / fans and valves present in thermal managementsystem of the electric vehicle.

[0050] In an aspect, the BCU on the other hand, optimizes functioning of the nonessentialloads. By optimization of the non-essential loads, it is meant that the BCU turnsOFF the non-essential loads like the Head up Display (HUD), the audio accessory outlet,the sunroof, the seat heating and the plurality of ventilation lights which do not come underhomologatory requirement. However, the BCU checks and regulates the other nonessentialloads accordingly depending on operating and surrounding conditions of vehicle.

[0051] In an aspect, like the BMS controller (102-1), the BCU also reduces powerconsumption of the electric vehicle by setting auto AC to a comparatively high temperatureand / or by reducing the blower speed.

[0052] In an aspect, upon negative determination of failure of the high power DC-DCconverter (110), the failsafe system (100) stops functioning and the electric vehicle resumesnormal operation.

[0053] In an aspect, the failsafe system (100) may also include a timer circuit that maybe fetched with a predefined time in order to wait and make sure that electric vehicle isexperiencing no power failure.

[0054] Further, in an aspect, upon failure of the high power DC-DC converter (110) ofthe electric vehicle, the VCU (124) activates a navigation system. The mode of operationand functioning of the navigation system is to be discussed in the subsequent section.

[0001] FIG. 3 represents an exemplary method associated with operation of the failsafesystem (100) in accordance with an exemplary embodiment of the present disclosure. Theorder in which the method (300) is described is not intended to be construed as a limitation,and any number of the described method blocks may be combined in any order toimplement the method (300), or an alternative method. Furthermore, the method (300) maybe implemented by processing device(s) or computing device(s) through any suitablehardware.

[0055] At block (302), the method includes simultaneous transmission of failure alertby a vehicle control unit (VCU) (124), regarding the failure of the high power DC-DCconverter (110), to a battery management system (BMS) controller (102-1) and a bodycontrol unit (BCU).

[0056] At block (304), the method includes activating, by the BMS controller, a lowpower dc-dc converter to establish a power supply connection with the essential loads (116)which were earlier connected to the high power DC-DC converter.

[0057] At block (306), the method includes establishing communication, by the BMScontroller (102-a), with a slave BMS (104) to monitor temperature and a voltage of a pluralityof cells present inside a battery pack of the electric vehicle.

[0058] At block (308), the method includes simultaneously optimizing, by the BCU , thefunctioning of non-essential loads(114), which were connected to the high power DC-DCconverter (110), based on operating and surrounding conditions of the vehicle.

[0059] At block (310), the method includes activating, by the VCU (124), an alertmechanism indicating an issue with the vehicle and prompting a user with the navigationsystem to initiate navigation of the vehicle to the nearest service station (SS). Herein, thealert mechanism may first generate an alert in a user infotainment system regardingindicating failure of a power source. After receiving a notification of failure of the powersource, the navigation system may be initiated representing a global position system (GPS)location of a plurality of service stations from the vehicle with their distances in metrics. Thisis followed by generating an estimate of the drivable range based on optimization of theessential and the non-essential loads that were initially connected to the high power DCDCconverter (110). As a result, the user gets thoroughly notified about the service stationslocated nearby so that the user can initiate navigation to a selected service station. Theservice station, on the other hand, also gets notified by the navigation system regarding thefailure of power source of the electric vehicle that needs immediate attention.

[0060] Therefore, in this manner, the failsafe system (100) operates and ensures thatthe electric vehicle can be driven up to the nearest service station in case of power failureor other emergency situations.Technical Advantages

[0061] All in all, the invention described in the present disclosure is having the followingadvantages:a) The failsafe system (100) provides an extra drivable time to the driver of the electricvehicle to reach nearby SSb) In the failsafe system (100), the low power DC-DC converter (102-4) gets activatedonly on account of failure of the high power DC-DC converter (110), therebyoptimizing consumption of power to a greater extent than the existing systemsc) The failsafe system (100) optimizes functioning of the non-essential loadsdepending on requirements and surrounding conditionsd) The failsafe system (100) provides an efficient approach to monitor the batterymanagement systeme) Power efficientEquivalents

[0062] It should be noted that the description and figures merely illustrate the principlesof the present subject matter. It should be appreciated by those skilled in the art thatconception and specific embodiment disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the same purposes of the presentsubject matter. It should also be appreciated by those skilled in the art that by devisingvarious systems that, although not explicitly described or shown herein, embody theprinciples of the present subject matter and are included within its spirit and scope.Furthermore, all examples recited herein are principally intended expressly to be forpedagogical purposes to aid the reader in understanding the principles of the presentsubject matter and the concepts contributed by the inventor(s) to furthering the art and areto be construed as being without limitation to such specifically recited examples andconditions. The novel features which are believed to be characteristic of the present subjectmatter, both as to its organization and method of operation, together with further objectsand advantages will be better understood from the following description when consideredin connection with the accompanying figures.

[0063] Although embodiments for the present subject matter have been described inlanguage specific to package features, it is to be understood that the present subject matteris not necessarily limited to the specific features described. Rather, the specific featuresand methods are disclosed as embodiments for the present subject matter. Numerousmodifications and adaptations of the system / device of the present invention will be apparentto those skilled in the art, and thus it is intended by the appended claims to cover all suchmodifications and adaptations which fall within the scope of the present subject matter.

[0064] It will be understood by those within the art that, in general, terms used herein,and especially in the appended claims (e.g., bodies of the appended claims) are generallyintended as "open" terms (e.g., the term "including" should be interpreted as "including butnot limited to," the term "having" should be interpreted as "having at least," the term"includes" should be interpreted as "includes but is not limited to," etc.). It will be furtherunderstood by those within the art that if a specific number of an introduced claim recitationis intended, such an intent will be explicitly recited in the claim, and in the absence of suchrecitation no such intent is present. For example, as an aid to understanding, the followingappended claims may contain usage of the introductory phrases "at least one" and "one ormore" to introduce claim recitations. However, the use of such phrases should not beconstrued to imply that the introduction of a claim recitation by the indefinite articles "a" or"an" limits any particular claim containing such introduced claim recitation to inventionscontaining only one such recitation, even when the same claim includes the introductoryphrases "one or more" or "at least one" and indefinite articles such as "a" or "an" (e.g., "a"and / or "an" should typically be interpreted to mean "at least one" or "one or more"); the sameholds true for the use of definite articles used to introduce claim recitations. In addition, evenif a specific number of an introduced claim recitation is explicitly recited, those skilled in theart will recognize that such recitation should typically be interpreted to mean at least therecited number (e.g., the bare recitation of "two recitations," without other modifiers, typicallymeans at least two recitations, or two or more recitations). Furthermore, in those instanceswhere a convention analogous to "at least one of A, B, and C, etc." is used, in general sucha construction is intended in the sense one having skill in the art would understand theconvention (e.g., "a system having at least one of A, B, and C" would include but not belimited to systems that have A alone, B alone, C alone, A and B together, A and C together,B and C together, and / or A, B, and C together, etc.). In those instances where a conventionanalogous to "at least one of A, B, or C, etc." is used, in general such a construction isintended in the sense one having skill in the art would understand the convention (e.g., "asystem having at least one of A, B, or C" would include but not be limited to systems thathave A alone, B alone, C alone, A and B together, A and C together, B and C together,and / or A, B, and C together, etc.). It will be further understood by those within the art thatvirtually any disjunctive word and / or phrase presenting two or more alternative terms,whether in the description, claims, or drawings, should be understood to contemplate thepossibilities of including one of the terms, either of the terms, or both terms. For example,the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B."

[0065] It will be further appreciated that functions or structures of a plurality ofcomponents or steps may be combined into a single component or step, or the functions orstructures of one-step or component may be split among plural steps or components. Thepresent invention contemplates all of these combinations. Unless stated otherwise,dimensions and geometries of the various structures depicted herein are not intended to berestrictive of the invention, and other dimensions or geometries are possible. In addition,while a feature of the present invention may have been described in the context of only oneof the illustrated embodiments, such feature may be combined with one or more otherfeatures of other embodiments, for any given application. It will also be appreciated fromthe above that the fabrication of the unique structures herein and the operation thereof alsoconstitute methods in accordance with the present invention. The present invention alsoencompasses intermediate and end products resulting from the practice of the methodsherein. The use of "comprising" or "including" also contemplates embodiments that "consistessentially of" or "consist of" the recited feature.

Claims

1. A failsafe system (100) for managing failure of a high power Direct Current - Direct Current (DC-DC) converter (110) in an electric vehicle, the system (100) comprising: - a master battery management system (BMS) (102) having: a BMS controller (102-1) to receive failure signal from a vehicle control unit (VCU) (124) regarding the failure of the high power DC-DC converter (110), and a low power DC-DC converter (102-4) activated by the BMS controller (102-1) in response to the receipt of the failure signal to enable the low power DC-DC converter (102-4) to establish a power supply connection with essential loads which were connected to the high power DC-DC converter (110); - a slave BMS (104) communicatively coupled to the master BMS (102) to receive the failure signal from the master BMS (102), wherein upon receipt of the alert signal, the slave BMS (104) monitors temperature and voltage of a plurality of cells present in a battery pack of the electric vehicle; and - a body control unit (BCU) or other controllers to simultaneously receive the failure signal from the VCU (124) for optimizing the functioning of non-essential loads, which were connected to the high power DC-DC converter (110), based on operating and surrounding conditions of the vehicle.

2. The failsafe system (100) as claimed in claim 1, wherein the BMS (102) comprises a decision module (102-2) that closes a relay (102-3) to establish a power supply connection of the low power DC-DC converter (102-4) with the essential loads (116) which were connected to the high power DC-DC converter (110).

3. The failsafe system (100) as claimed in claim 1, wherein the essential loads(116) include a multitude of controllers, a multitude of sensors, and a multitude of safety critical devices.

4. The failsafe system (100) as claimed in claim 1, wherein the non-essential loads include a Head Up Display (HUD), an audio accessory outlet, a sunroof, a seat heating, and a plurality of ventilation lights.

5. The failsafe system (100) as claimed in claim 1, wherein other non-essential loads include a head lamp, a radiator fan, air conditioner blower, defogger, and battery cell cooling fans.

6. The failsafe system (100) as claimed in claim 1, extends a drivable range during failure of the high power Direct Current - Direct Current (DC-DC) converter (110) in the electric vehicle.

7. A method for operating a failsafe system managing failure of a high power Direct Current - Direct Current (DC-DC) converter (110) in an electric vehicle, the method comprising: - simultaneously transmitting, by a vehicle control unit (VCU) (124), a failure alert regarding the failure of the high power DC-DC converter (110), to a battery management system (BMS) controller (102-1) and a body control unit (BCU) (116); - activating, by the BMS controller (102-1), a low power DC-DC converter (102-4) to establish a power supply connection with the essential loads (116) which were connected to the high power DC-DC convertor (110); - establishing communication, by the BMS controller (102-1), with a slave BMS to monitor temperature and voltage of a plurality of cells present inside a battery pack of the electric vehicle; - simultaneously optimizing, by the BCU or other controllers), the functioning of non-essential loads, which were connected to the high power DC-DC converter (110), based on operating and surrounding conditions of the vehicle; and - activating, by the VCU (124), an alert mechanism indicating an issue with the vehicle and prompting a user with a navigation system to initiate navigation of the vehicle to the nearest service station (SS).

8. The method as claimed in claim 7, wherein the activating the alert mechanism comprises: generating an alert indication in a user infotainment system regarding a power source failure; initiating the navigation system representing a global position system (GPS) location of a plurality of service stations from the vehicle; and generating output of an estimate of the drivable range based on the optimization of the essential and non-essential loads which were connected to the high power DC-DC converter (110).

9. The method as claimed in claim 8, wherein the method comprising, when the user initiates the navigation to a selected service station, intimating the selected service station (SS).