A transmission system for an electric vehicle

Abstract

The present disclosure discloses a transmission system (100) for an electric vehicle (200). The transmission system (100) may include a transmission control unit (102), a one-way clutch assembly (110), a friction clutch assembly (112), and a bypass mechanism (118). The transmission control unit (102) is adapted to determine a vehicle speed and a throttle position based on an input received from a plurality of sensors mounted on the vehicle (200). The one-way clutch assembly (110) is adapted to be mounted on an input shaft (104) and operatively coupled to a first gear drive (114). The transmission control unit (102) may at least activate the bypass mechanism (118) and de-actuate the friction clutch assembly (112) to restrict a transfer of power from an output shaft (106) to the input shaft (104) based on the vehicle speed and the throttle position.

Description

[0001] TITLE

[0002] A Transmission System for an Electric Vehicle

[0003] FIELD OF THE INVENTION

[0004] The present disclosure relates to electric vehicles and more particularly, to a transmission system for an electric vehicle.

[0005] BACKGROUND

[0006] Nowadays, electric vehicles (EVs) have become popular due to heightened environmental concerns and increased cost competitiveness with conventional gas vehicles. Typically, an electric vehicle such as a three-wheeler, or a four-wheeler, is equipped with a battery, a power electronic unit, an electric machine and a transmission system connected to the electric machine. The existing electric vehicles are equipped with regenerative braking to transform the kinetic energy into electric power in a recuperation mode. In the recuperation mode, the transmission system transmits the energy from an output shaft to an input shaft of the electric vehicle, and the recuperated energy can be stored in the battery or dissipated.

[0007] Currently, the recuperated energy is stored in the battery of the electric vehicle. However, the recuperated energy cannot be stored in the battery when the battery is fully charged. In such scenarios, the excess recuperated energy is dissipated in the form of heat from the power electronic unit, such as a capacitor. This reduces the efficiency of the power electronic unit. Further, it becomes difficult to dissipate the recuperated energy through the power electronic unit, when the electric machine produces the recuperated energy more than storing capacity of the power electronics unit. This may cause short-circuiting may which leads to the damage or malfunctioning of the electric machine, and other components of the electric vehicle. Therefore, in view of the above-mentioned problems, there is a need to provide a transmission system that can eliminate one or more above-mentioned problems associated with the existing transmission systems.

[0008] SUMMARY

[0009] This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.

[0010] The present disclosure discloses a transmission system for an electric vehicle. The transmission system may include a transmission control unit, a one-way clutch assembly, a friction clutch assembly, and a bypass mechanism. The transmission control unit is adapted to determine a vehicle speed and a throttle position based on an input received from a plurality of sensors mounted on the vehicle. The one-way clutch assembly is adapted to be mounted on an input shaft and operatively coupled to a first gear drive. The friction clutch assembly is adapted to be mounted on the input shaft and operatively coupled to a second gear drive and the first gear drive. The bypass mechanism is adapted to bypass the one-way clutch assembly. The transmission control unit is adapted to at least activate the bypass mechanism and de-actuate the friction clutch assembly to restrict a transfer of power from an output shaft to the input shaft based on the vehicle speed and the throttle position.

[0011] Further, a transmission system for an electric vehicle is disclosed in the present disclosure. The transmission system may include a transmission control unit, a first clutch assembly, and a second clutch assembly. The transmission control unit is adapted to determine a vehicle speed, and a throttle position based on an input received from a plurality of sensors mounted on the vehicle. The first clutch assembly is adapted to be mounted on an input shaft and operatively coupled to a first gear drive. The second clutch assembly is adapted to be mounted on the input shaft and operatively coupled to a second gear drive. The transmission control unit is adapted to at least de-actuate the first clutch assembly and the second clutch assembly to restrict a transfer of power from an output shaft to the input shaft based on the vehicle speed and the throttle position.

[0012] Moreover, the present disclosure discloses a method for controlling a transmission system of an electric vehicle. The method may include determining, by a transmission control unit, a vehicle speed and a throttle position based on an input received from a plurality of sensors mounted on the vehicle. The method may include deactivating, by the transmission control unit, at least one of a first clutch assembly operatively coupled to a first gear drive, to restrict a transfer of power from an output shaft to an input shaft when the throttle position and the vehicle speed are less than a predefined throttle position and a predefined vehicle speed, respectively; and a second clutch assembly operatively coupled to a second gear drive, to restrict the transfer of power from the output shaft to the input shaft when the throttle position and the vehicle speed are greater than the predefined throttle position and the predefined vehicle speed, respectively.

[0013] To further clarify advantages and features of the present disclosure, a more particular description of the invention will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

[0014] BRIEF DESCRIPTION OF THE DRAWINGS

[0015] These and other features, aspects, and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[0016] Figure 1 illustrates a partial schematic view of an electric vehicle, according to an embodiment of the present disclosure;

[0017] Figure 2 illustrates a block diagram depicting a transmission control unit of the electric vehicle, according to an embodiment of the present disclosure;

[0018] Figures 3(a), 3(b), and 3(c) illustrate schematic views of a transmission system of the electric vehicle, according to an embodiment of the present disclosure;

[0019] Figure 4(a) illustrates a schematic view of the transmission system having a friction clutch assembly and a one-way clutch (OWC) assembly with a bypass mechanism, according to an embodiment of the present disclosure;

[0020] Figure 4(b) illustrates a flowchart depicting an operation of the transmission system of Figure 4(a), according to an embodiment of the present disclosure;

[0021] Figure 5(a) illustrates a schematic view of the transmission system having the friction clutch assembly and the one-way clutch (OWC) assembly without the bypass mechanism, according to an embodiment of the present disclosure;

[0022] Figure 5(b) illustrates a flowchart depicting an operation of the transmission system of Figure 5(a), according to an embodiment of the present disclosure;

[0023] Figure 6(a) illustrates a schematic view of the transmission system having the first friction clutch assembly and a second friction clutch assembly, according to an embodiment of the present disclosure; Figure 6(b) illustrates a flowchart depicting an operation of the transmission system of Figure 6(a), according to an embodiment of the present disclosure; and

[0024] Figure 7 illustrates a flowchart depicting a method for controlling the transmission system, according to an embodiment of the present disclosure.

[0025] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present disclosure. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the embodiments of the present disclosure so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

[0026] DETAILED DESCRIPTION OF FIGURES

[0027] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting. The term “some” as used herein is defined as “none, or one, or more than one, or all.” Accordingly, the terms “none,” “one,” “more than one,” “more than one, but not all” or “all” would all fall under the definition of “some.” The term “some embodiments” may refer to no embodiments or to one embodiment or to several embodiments or to all embodiments. Accordingly, the term “some embodiments” is defined as meaning “no embodiment, or one embodiment, or more than one embodiment, or all embodiments.”

[0028] The terminology and structure employed herein is for describing, teaching and illuminating some embodiments and their specific features and elements and does not limit, restrict or reduce the spirit and scope of the claims or their equivalents.

[0029] More specifically, any terms used herein such as but not limited to “includes,” “comprises,” “has,” “consists,” and grammatical variants thereof do NOT specify an exact limitation or restriction and certainly do NOT exclude the possible addition of one or more features or elements, unless otherwise stated, and furthermore must NOT be taken to exclude the possible removal of one or more of the listed features and elements, unless otherwise stated with the limiting language “MUST comprise” or “NEEDS TO include.”

[0030] Whether or not a certain feature or element was limited to being used only once, either way it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do NOT preclude there being none of that feature or element, unless otherwise specified by limiting language such as “there NEEDS to be one or more . . . ” or “one or more element is REQUIRED.” Unless otherwise defined, all terms, and especially any technical and / or scientific terms, used herein may be taken to have the same meaning as commonly understood by one having an ordinary skill in the art.

[0031] Reference is made herein to some “embodiments.” It should be understood that an embodiment is an example of a possible implementation of any features and / or elements presented in the attached claims. Some embodiments have been described for the purpose of illuminating one or more of the potential ways in which the specific features and / or elements of the attached claims fulfil the requirements of uniqueness, utility and non-obviousness.

[0032] Use of the phrases and / or terms such as but not limited to “a first embodiment,” “a further embodiment,” “an alternate embodiment,” “one embodiment,” “an embodiment,” “multiple embodiments,” “some embodiments,” “other embodiments,” “further embodiment”, “furthermore embodiment”, “additional embodiment” or variants thereof do NOT necessarily refer to the same embodiments. Unless otherwise specified, one or more particular features and / or elements described in connection with one or more embodiments may be found in one embodiment, or may be found in more than one embodiment, or may be found in all embodiments, or may be found in no embodiments. Although one or more features and / or elements may be described herein in the context of only a single embodiment, or alternatively in the context of more than one embodiment, or further alternatively in the context of all embodiments, the features and / or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and / or elements described in the context of separate embodiments may alternatively be realized as existing together in the context of a single embodiment.

[0033] Any particular and all details set forth herein are used in the context of some embodiments and therefore should NOT be necessarily taken as limiting factors to the attached claims. The attached claims and their legal equivalents can be realized in the context of embodiments other than the ones used as illustrative examples in the description below.

[0034] Embodiments of the present disclosure will be described below in detail with reference to the accompanying drawings.

[0035] Figure 1 illustrates a partial schematic view of an electric vehicle 200 while Figure 2 illustrates a block diagram depicting a transmission control unit 102 of the electric vehicle 200. Referring to Figures 1, 2, the electric vehicle 200 may include a transmission system 100 and an electric machine 210 coupled with the transmission system 100. The electric machine 210 is powered by a battery 202 through various converters such as a DC-DC converter 206 and an inverter 208. Further, the electric vehicle 200 may include a Vehicle Control Unit (VCU) 212 and the Transmission Control Unit (TCU) 102. The VCU 212 is electrically connected to the TCU 102 to provide control signals to the TCU 102. Further, the VCU 212 and the TCU 102 may be connected to a Battery Management System (BMS) 204 provided with the battery 202.

[0036] The electric machine 210 may operate as an electric motor 210 and an electric generator depending on the control signals from the VCU 212. In one example, the electric machine 210 may operate as the motor 210 during a normal mode of the electric vehicle 200. In another example, the electric machine 210 may operate as the electric generator during regenerative braking or in a recuperation mode of the electric vehicle 200 to charge the battery 202. Herein, the transmission system 100 is coupled to a plurality of wheels 214 of the electric vehicle 200.

[0037] The VCU 212 may include, but is not limited to, an inclination sensor, a throttle position sensor 222, an ignition switch, a brake input, and a reverse input. The VCU 212 may be in communication with the TCU 102. The TCU 102 may be configured to control the transmission system 100 based on the instructions received from the VCU 212. The TCU 102 may be connected to a plurality of sensors, such that the TCU 102 may be adapted to determine a vehicle speed, and a throttle position based on an input received from the plurality of sensors mounted on the electric vehicle 200. The plurality of sensors may include, but is not limited to, a vehicle speed sensor 216, a clutch position sensor 220, and a one-way clutch (OWC) bypass position sensor 218. The TCU 102 may be connected to an indication unit 224 adapted to display one of a transmission mode indication, a clutches states indication, and a reverse indication, based on the inputs received from the TCU 102. Further, the TCU 102 may be connected to a friction clutch actuator 226 and an OWC bypass actuator 228.

[0038] Figures 3(a), 3(b), and 3(c) illustrate schematic views of the transmission system 100 of the electric vehicle 200. Referring to Figures 3(a), 3(b), and 3(c), the transmission system 100 may be adapted to be installed in the electric vehicle 200. The transmission system 100 may include an input shaft 104, an output shaft 106, a differential 108, the TCU 102, a first clutch assembly, and a second clutch assembly. Herein, the first clutch assembly may be embodied as one of a one-way clutch (OWC) assembly 110 and a friction clutch assembly 112, without departing from the scope of the present disclosure. Further, the second clutch assembly may be embodied as one of the OWC assembly 110 and the friction clutch assembly 112, without departing from the scope of the present disclosure.

[0039] The first clutch assembly and the second clutch assembly are adapted to engage the input shaft 104 with the output shaft 106 to transmit the torque. The input shaft 104 may be adapted to drive the differential 108 through the output shaft 106. The differential 108 may drive an axle of the electric vehicle 200. The input shaft 104 may be coupled to the electric machine 210 to receive the torque. The differential 108 may be adapted to transmit the torque to the plurality of wheels 214 of the electric vehicle 200. In an embodiment, the differential 108 may be a dual crown differential. In the illustrated embodiment as shown in Figure 3(a), the first clutch assembly and the second clutch assembly may be adapted to be mounted on the output shaft 106. In another embodiment, referring to Figure 3(b), the first clutch assembly may be adapted to be mounted on the input shaft 104, and the second clutch assembly may be adapted to be mounted on the output shaft 106. In one more embodiment, referring to Figure 3(c), the first clutch assembly may be adapted to be mounted on the output shaft 106, and the second clutch assembly may be adapted to be mounted on the input shaft 104. The first clutch assembly may be operatively coupled to a first gear drive 114, and the second clutch assembly may be operatively coupled to a second gear drive 116. Herein, the first gear drive 114 may include a first set of gears, and the second gear drive 116 may include a second set of gears.

[0040] The TCU 102 may be adapted to determine the vehicle speed and the throttle position based on an input received from the plurality of sensors such as the vehicle speed sensor 216 and the throttle position sensor 222. Herein, the vehicle speed sensor 216 may be adapted to determine the speed of the electric vehicle 200. The throttle position sensor 222 is adapted to determine the throttle position of the electric vehicle 200. The TCU 102 is adapted to at least de-actuate the first clutch assembly and the second clutch assembly to restrict a transfer of power from the output shaft 106 to the input shaft 104 based on the vehicle speed and the throttle position. Thus, the transmission of power from the output shaft 106 to the input shaft 104, may be restricted, even in a recuperation mode. This prevents the damage or failure of the power electronic unit as the power is not required to be dissipated through the power electronic unit.

[0041] The TCU 102 may be adapted to determine whether the throttle position is less than or greater than a predefined throttle position. Further, the TCU 102 may be adapted to determine whether the vehicle speed is less than or greater than a predefined vehicle speed. Herein, the predefined throttle position may define a throttle position at which a shifting from the first gear drive 114 to the second gear drive 116 is performed. The predefined vehicle speed may define a vehicle speed at which a shifting from the first gear drive 114 to the second gear drive 116 is performed.

[0042] The TCU 102 may be adapted to de-actuate one of the first clutch assembly and the second clutch assembly to restrict the transfer through the first gear drive 114 and the second gear drive 116, respectively. The TCU 102 may de-actuate the first clutch assembly to restrict the transfer of power from the output shaft 106 to the input shaft 104 through the first gear drive 114, when the vehicle speed and the throttle position are less than the predefined throttle position and the predefined vehicle speed, respectively. Further, the TCU 102 may de-actuate the second clutch assembly to restrict the transfer of power from the output shaft 106 to the input shaft 104 through the second gear drive 116, when the vehicle speed and the throttle position are greater than the predefined throttle position and the predefined vehicle speed, respectively.

[0043] Figure 4(a) illustrates a schematic view of the transmission system 100 having the friction clutch assembly 112 and the OWC assembly 110 with a bypass mechanism 118 while Figure 4(b) illustrates a flowchart depicting an operation of the transmission system 100 of Figure 4(a). Referring to Figure 4(a), the first clutch assembly is embodied as the OWC assembly 110 operatively coupled to the first gear drive 114 and the second clutch assembly is embodied as a friction clutch assembly 112 operatively coupled to the second gear drive 116. Herein, the transmission system 100 may include the TCU 102, the OWC assembly 110, the friction clutch assembly 112, and the bypass mechanism 118.

[0044] The TCU 102 may be adapted to determine the vehicle speed and the throttle position based on the input received from the plurality of sensors mounted on the vehicle 200. The plurality of sensors may include the vehicle speed sensor 216 and the throttle position sensor 222. The OWC assembly 110 may be adapted to be mounted on the input shaft 104 and operatively coupled to the first gear drive 114. The friction clutch assembly 112 may be adapted to be mounted on the input shaft 104 and operatively coupled to the second gear drive 116 and the first gear drive 114. The bypass mechanism 118 may be adapted to bypass the OWC assembly 110. The TCU 102 may be adapted to at least activate the bypass mechanism 118 and de-actuate the friction clutch assembly 112 to restrict the transfer of power from the output shaft 106 to the input shaft 104 based on the vehicle speed and the throttle position.

[0045] The bypass mechanism 118 may include a reverse ratchet actuator unit adapted to be actuated to slip the OWC assembly 110. Thus, the bypass mechanism 118 may be activated to slip the OWC assembly 110, such that the transmission of power from the output shaft 106 to the input shaft 104 may be restricted.

[0046] Referring to Figure 4(b), at block 402, the electric machine, such as a motor 210, may be started to supply power to move the electric vehicle 200. Further, at block 404, the TCU 102 may determine whether the throttle position is less than or greater than the predefined throttle position (UPS throttle %). If the throttle position is less than the predefined throttle position (UPS throttle %), then the operation of transmission system 100 proceeds to block 406. Alternatively, if the throttle position is greater than a predefined throttle position, then the operation proceeds to block 408.

[0047] At block 406, the TCU 102 may determine whether the vehicle speed is less than or greater than the predefined vehicle speed. If the vehicle speed is less than the predefined vehicle speed (UPS vehicle speed), then the operation of the TCU 100 proceeds to block 410. Alternatively, if the vehicle speed is greater than the predefined vehicle speed (UPS vehicle speed), then the operation proceeds to block 408. Further, at block 410, the TCU 102 actuates the reverse ratchet actuator unit of the OWC assembly 110. At block 412, the TCU 102 may check whether the OWC bypass mechanism 118 is active or not. If the OWC bypass mechanism 118 is not active, the operation again moves to block 410. Alternatively, if the OWC bypass mechanism 118 is active, then the OWC assembly 110 is deactivated and the operation proceeds to further block 414.

[0048] At block 414, the friction clutch actuator 226 is turned ON, and the operation proceeds to block 416. At block 416, the TCU 102 may check whether the friction clutch assembly 112 is fully opened or not, based on the input indicative of the clutch position sensor 220. If the friction clutch assembly 112 is not fully opened, then the operation returns to the block 414. Alternatively, if the friction clutch assembly 112 is fully opened, then the operation proceeds to block 418. At block 418, the friction clutch actuator 226 is turned OFF, and the operation proceeds to block 420. At block 420, the transmission of power from the output shaft 106 to input shaft 104 through the first gear drive 114 is restricted based on the vehicle speed and the throttle position.

[0049] At block 408, the TCU 102 may determine whether the throttle position is greater than the predefined throttle position (UPS throttle %), and whether the vehicle speed greater than the predefined vehicle speed (UPS vehicle speed). If yes, then operation proceeds to block 422. At block 422, the friction clutch actuator 226 is turned ON, and the operation proceeds to block 424.

[0050] At block 424, the TCU 102 may check whether the friction clutch assembly 112 is fully opened or not, based on the input indicative of the clutch position sensor 220. If the friction clutch assembly 112 is not fully opened, then the operation returns to the block 422. Alternatively, if the friction clutch assembly 112 is fully opened, then the operation proceeds to block 426. At block 426, the friction clutch actuator 226 is turned OFF, and the operation proceeds to block 428. At block 428, the transmission of power from the output shaft 106 to input shaft 104 through the second gear drive 116 is restricted based on the vehicle speed and the throttle position. Figure 5(a) illustrates a schematic view of the transmission system 100 having the friction clutch assembly 112 and the OWC assembly 110 without the bypass mechanism 118, while Figure 5(b) illustrates a flowchart depicting an operation of the transmission system 100 of Figure 5(a). Referring to Figure 5(a), the first clutch assembly is embodied as the OWC assembly 110 operatively coupled to the first gear drive 114, and the second clutch assembly is embodied as the friction clutch assembly 112 operatively coupled to the second gear drive 116. Herein, the transmission system 100 may include the TCU 102, the OWC assembly 110, and the friction clutch assembly 112.

[0051] Referring to Figure 5(b), at block 502, the electric machine such as a motor 210 may be started to supply power to move the electric vehicle 200. Further, at block 504, the TCU 102 may determine whether the throttle position is less than or greater than the predefined throttle position (UPS throttle %). If the throttle position is less than the predefined throttle position (UPS throttle %), then the operation of transmission system 100 proceeds to block 506. Alternatively, if the throttle position is greater than a predefined throttle position, then the operation proceeds to block 508.

[0052] At block 506, the TCU 102 may determine whether the vehicle speed is less than or greater than the predefined vehicle speed. If the vehicle speed is less than the predefined vehicle speed (UPS vehicle speed), then the operation of the TCU 100 proceeds to block 510. Alternatively, if the vehicle speed is greater than the predefined vehicle speed (UPS vehicle speed), then the operation proceeds to block 508. Further, at block 510, the OWC assembly 110 may slip and the operation proceeds to further block 512. At block 512, the transmission of power from the output shaft 106 to input shaft 104 through the first gear drive 114 is restricted based on the vehicle speed and the throttle position. At block 508, the TCU 102 may determine whether the throttle position is greater than the predefined throttle position (UPS throttle %), and whether the vehicle speed greater than the predefined vehicle speed (UPS vehicle speed). If yes, then operation proceeds to block 514. At block 514, the friction clutch actuator 226 is turned ON, and the operation proceeds to block 516. At block 516, the TCU 102 may check whether the friction clutch assembly 112 is fully opened or not, based on the input indicative of the clutch position sensor 220. If the friction clutch assembly 112 is not fully opened, then the operation returns to the block 514. Alternatively, if the friction clutch assembly 112 is fully opened, then the operation proceeds to block 518. At block 518, the friction clutch actuator 226 is turned OFF, and the operation proceeds to block 520. At block 520, the transmission of power from the output shaft 106 to input shaft 104 through the second gear drive 116 is restricted based on the vehicle speed and the throttle position.

[0053] Figure 6(a) illustrates a schematic view of the transmission system 100 having the first friction clutch assembly and the second friction clutch assembly while Figure 6(b) illustrates a flowchart depicting an operation of the transmission system 100 of Figure 6(a). Referring to Figure 6(a), the first clutch assembly may be embodied as the first friction clutch assembly operatively coupled to the first gear drive 114 and the second clutch assembly is embodied as the first friction clutch assembly operatively coupled to the second gear drive 116. A first friction clutch actuator is coupled to the first friction clutch assembly, and a second friction clutch actuator is coupled to the second friction clutch assembly. Herein, the first friction clutch assembly and the second friction clutch assembly may be collectively referred to as the dual friction clutch assembly 112.

[0054] Referring to Figure 6(b), at block 602, the electric machine such as a motor 210 may be started to supply power to move the electric vehicle 200. Further, at block 604, the TCU 102 may determine whether the throttle position is less than or greater than the predefined throttle position (UPS throttle %). If the throttle position is less than the predefined throttle position (UPS throttle %), then the operation of transmission system 100 proceeds to block 606. Alternatively, if the throttle position is greater than a predefined throttle position, then the operation proceeds to block 608.

[0055] At block 606, the TCU 102 may determine whether the vehicle speed is less than or greater than the predefined vehicle speed. If the vehicle speed is less than the predefined vehicle speed (UPS vehicle speed), then the operation of the TCU 100 proceeds to block 610. Alternatively, if the vehicle speed is greater than the predefined vehicle speed (UPS vehicle speed), then the operation proceeds to block 608. Further, at block 610, the first friction clutch actuator is turned ON, and the operation proceeds to block 612. At block 612, the TCU 102 may check whether the friction clutch assembly 112 is fully opened or not, based on the input indicative of the clutch position sensor 220. If the friction clutch assembly 112 is fully opened, then the operation proceeds to block 614. At block 614, the first friction clutch actuator is turned OFF, and the operation proceeds to block 616. At block 616, the transmission of power from the output shaft 106 to input shaft 104 through the first gear drive 114 is restricted based on the vehicle speed and the throttle position.

[0056] At block 608, the TCU 102 may determine whether the throttle position is greater than the predefined throttle position (UPS throttle %), and whether the vehicle speed greater than the predefined vehicle speed (UPS vehicle speed). If yes, then operation proceeds to block 618. At block 618, the second friction clutch actuator is turned ON, and the operation proceeds to block 620. At block 620, the TCU 102 may check whether the friction clutch assembly 112 is fully opened or not, based on the input indicative of the clutch position sensor 220. If the friction clutch assembly 112 is not fully opened, then the operation returns to the block 618. Alternatively, if the friction clutch assembly 112 is fully opened, then the operation proceeds to block 622. At block 622, the second friction clutch actuator is turned OFF, and the operation proceeds to block 624. At block 624, the transmission of power from the output shaft 106 to input shaft 104 through the second gear drive 116 is restricted based on the vehicle speed and the throttle position. The present disclosure also relates to a method for controlling the transmission system 100 of an electric vehicle 200, as shown in Figure 7. The order in which the method steps are described below is not intended to be construed as a limitation, and any number of the described method steps can be combined in any appropriate order to execute the method or an alternative method. Additionally, individual steps may be deleted from the method without departing from the spirit and scope of the subject matter described herein.

[0057] Moreover, the present disclosure discloses a method 700 for controlling a transmission system 100 of an electric vehicle 200. The method begins at step 702 in which the vehicle speed and a throttle position may be determined, by the TCU 102, based on an input received from the plurality of sensors mounted on the vehicle 200. Herein, the plurality of sensors may include the vehicle speed sensor 216 and the throttle position sensor 222. The vehicle speed sensor 216 may determine the vehicle speed and transmit the inputs indicative of the vehicle speed to the TCU 102. Similarly, the throttle position sensor 222 may determine the throttle position of the electric vehicle and transmit the inputs indicative of the throttle position to the TCU 102.

[0058] Further, at step 704, the method may include deactivating, by the TCU 102, at least one of the first clutch assembly and the second clutch assembly. Herein, the first clutch assembly may be deactivated to restrict a transfer of power from an output shaft 106 to an input shaft 104 when the throttle position and the vehicle speed are less than the predefined throttle position and the predefined vehicle speed, respectively. Further, the second clutch assembly may be deactivated to restrict the transfer of power from the output shaft 106 to the input shaft 104 when the throttle position and the vehicle speed are greater than the predefined throttle position and the predefined vehicle speed, respectively. The transmission system 100 includes the TCU 102, the bypass mechanism 118, the OWC assembly 110 and the friction clutch assembly 112. Herein, the TCU 102 may activate the bypass mechanism 118 and deactivate the friction clutch assembly 112 based on the vehicle speed and the throttle position. The activation of the bypass mechanism 118 may slip or deactivate the OWC assembly 110. The deactivation of the OWC assembly 110 and the friction clutch assembly 112 may restrict the transfer of power from the output shaft 106 to the input shaft 104. Thus, the transmission of power from the output shaft 106 to the input shaft 104, can be restricted, even in the recuperation mode. This prevents the damage or failure of the power electronic unit as the power is not required to be dissipated through the power electronic unit. Further, this improves the overall efficiency and working of the electric machine as the short-circuiting due to the excess power is avoided.

[0059] Further, in another embodiment, the transmission system 100 includes the TCU 102, the OWC assembly 110 and the friction clutch assembly 112. The TCU 102 may de-actuate the OWC assembly 110 and the friction clutch assembly 112 to restrict the transfer of power from the output shaft 106 to the input shaft 104 based on the vehicle speed and the throttle position. The deactivation of OWC assembly 110 and the friction clutch assembly 112 may restrict the transfer of power from the output shaft 106 to the input shaft 104.

[0060] Moreover, in one embodiment, the transmission system 100 includes the TCU 102, the first friction clutch assembly and the second friction clutch assembly. The TCU 102 may de-actuate the first friction clutch assembly and the second friction clutch assembly to restrict a transfer of power from an output shaft 106 to the input shaft 104 based on the vehicle speed and the throttle position. The deactivation of the first friction clutch assembly and the second friction clutch assembly may restrict the transfer of power from the output shaft 106 to the input shaft 104. While specific language has been used to describe the present subject matter, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of embodiments. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one embodiment may be added to another embodiment.

Claims

We Claim:

1. A transmission system (100) for an electric vehicle (200), the transmission system (100) comprising: a transmission control unit (102) adapted to determine a vehicle speed and a throttle position based on an input received from a plurality of sensors mounted on the vehicle (200); and a one-way clutch assembly (110) adapted to be mounted on an input shaft (104) and operatively coupled to a first gear drive (114); a friction clutch assembly (112) to be mounted on the input shaft (104) and operatively coupled to a second gear drive (116) and the first gear drive (114); and a bypass mechanism (118) adapted to bypass the one-way clutch assembly (110), wherein the transmission control unit (102) is adapted to at least activate the bypass mechanism (118) and de-actuate the friction clutch assembly (112) to restrict a transfer of power from an output shaft (106) to the input shaft (104) based on the vehicle speed and the throttle position.

2. The transmission system (100) as claimed in claim 1, wherein: the transmission control unit (102) is adapted to determine whether the throttle position is less than or greater than a predefined throttle position; and the transmission control unit (102) is adapted to determine whether the vehicle speed is less than or greater than a predefined vehicle speed.

3. The transmission system (100) as claimed in claim 2, wherein: the predefined throttle position defines a throttle position at which a shifting from the first gear drive (114) to the second gear drive (116) is performed; andthe predefined vehicle speed defines a vehicle speed at which the shifting from the first gear drive (114) to the second gear drive (116) is performed.

4. The transmission system (100) as claimed in claim 2, wherein the transmission control unit (102) is adapted to actuate the bypass mechanism (118) and de-actuate the friction clutch assembly (112) to restrict the transfer of power from the output shaft (106) to the input shaft (104) through the first gear drive (114), when the vehicle speed and the throttle position are less than the predefined throttle position and the predefined vehicle speed, respectively.

5. The transmission system (100) as claimed in claim 2, wherein the transmission control unit (102) is adapted to de-actuate the friction clutch assembly (112) to restrict the transfer of power from the output shaft (106) to the input shaft (104) through the second gear drive (116), when the vehicle speed and the throttle position are greater than the predefined throttle position and the predefined vehicle speed, respectively.

6. The transmission system (100) as claimed in claim 1, comprising a reverse ratchet actuator unit adapted to control the bypass mechanism (118), wherein the bypass mechanism (118) is adapted to bypass the one-way clutch assembly (110) to restrict the transmission of power from the output shaft (106) to the input shaft (104), when the vehicle speed and the throttle position are less than the predefined throttle position and the predefined vehicle speed, respectively.

7. The transmission system (100) as claimed in claim 1 comprising a friction clutch actuator (226) connected with the transmission control unit (102) and adapted to control the friction clutch assembly (112) to restrict the transmission of power from the output shaft (106) to the input shaft (104),when the vehicle speed and the throttle position are greater than the predefined throttle position and the predefined vehicle speed, respectively.

8. A transmission system (100) for an electric vehicle (200), the transmission system (100) comprising: a transmission control unit (102) adapted to determine a vehicle speed, and a throttle position based on an input received from a plurality of sensors mounted on the vehicle (200); and a first clutch assembly adapted to be mounted on an input shaft (104) and operatively coupled to a first gear drive (114); a second clutch assembly adapted to be mounted on the input shaft (104) and operatively coupled to a second gear drive (116); and wherein the transmission control unit (102) is adapted to at least deactuate the first clutch assembly and the second clutch assembly to restrict a transfer of power from an output shaft (106) to the input shaft (104) based on the vehicle speed and the throttle position.

9. The transmission system (100) as claimed in claim 8, wherein: the transmission control unit (102) is adapted to determine whether the throttle position is less than or greater than a predefined throttle position; and the transmission control unit (102) is adapted to determine whether the vehicle speed is less than or greater than a predefined vehicle speed.

10. The transmission system (100) as claimed in claim 9, wherein: the predefined throttle position defines a throttle position at which a shifting from the first gear drive (114) to the second gear drive (116) is performed; and the predefined vehicle speed defines a vehicle speed at which a shifting from the first gear drive (114) to the second gear drive (116) is performed.

11. The transmission system (100) as claimed in claims 8 or 9, wherein the transmission control unit (102) is adapted to de-actuate the first clutch assembly to restrict the transfer of power from the output shaft (106) to the input shaft (104) through the first gear drive (114), when the vehicle speed and the throttle position are less than the predefined throttle position and the predefined vehicle speed, respectively.

12. The transmission system (100) as claimed in claims 8 or 9, wherein the transmission control unit (102) is adapted to de-actuate the second clutch assembly to restrict the transfer of power from the output shaft (106) to the input shaft (104) through the second gear drive (116), when the vehicle speed and the throttle position are greater than the predefined throttle position and the predefined vehicle speed, respectively.

13. The transmission system (100) as claimed in claim 8, wherein the first clutch assembly is embodied as a one-way clutch assembly (110) operatively coupled to the first gear drive (114); and wherein the second clutch assembly is embodied as a friction clutch assembly (112) operatively coupled to the second gear drive (116).

14. The transmission system (100) as claimed in claim 8, wherein the first clutch assembly is embodied as a first friction clutch assembly (112) operatively coupled to the first gear drive (114); and wherein the second clutch assembly is embodied as a second friction clutch assembly (112) operatively coupled to the second gear drive (116).

15. A method (700) for controlling a transmission system (100) of an electric vehicle (200), the method comprising:determining (702), by a transmission control unit (102), a vehicle speed and a throttle position based on an input received from a plurality of sensors mounted on the vehicle (200); deactivating (704), by the transmission control unit (102), at least one of: a first clutch assembly operatively coupled to a first gear drive (114), to restrict a transfer of power from an output shaft (106) to an input shaft (104) when the throttle position and the vehicle speed are less than the predefined throttle position and the predefined vehicle speed, respectively; and a second clutch assembly operatively coupled to a second gear drive (116), to restrict the transfer of power from the output shaft (106) to the input shaft (104) when the throttle position and the vehicle speed are greater than the predefined throttle position and the predefined vehicle speed, respectively.

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