Transmission system for electric vehicle

Abstract

The present disclosure discloses a drivetrain (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 inputs received from a plurality of sensors mounted on the vehicle (200). The one-way clutch assembly (110) is adapted to be mounted on the input shaft (104) and operatively coupled to the first gear drive (114). The transmission control unit (102) may activate at least the bypass mechanism (118) and deactivate the friction clutch assembly (112) based on vehicle speed and throttle position to limit power transfer from the output shaft (106) to the input shaft (104).

Description

Technical Field

[0001] This disclosure relates to electric vehicles, and more specifically, to drive systems for electric vehicles. Background Technology

[0002] Electric vehicles (EVs) have become increasingly popular due to growing environmental concerns and their improved cost competitiveness compared to conventional gasoline vehicles. Typically, EVs, such as three-wheeled or four-wheeled vehicles, are equipped with a battery, power electronics unit, motor, and drivetrain connected to the motor. Existing EVs are equipped with regenerative braking systems to convert kinetic energy into electricity in regeneration mode. In regeneration mode, the drivetrain transfers energy from the EV's output shaft to its input shaft, and the recovered energy can be stored in the battery or dissipated.

[0003] Currently, recovered energy is stored in the batteries of electric vehicles. However, when the battery is fully charged, the recovered energy cannot be stored in the battery. In this case, the excess recovered energy is dissipated as heat from the power electronics unit, such as capacitors. This reduces the efficiency of the power electronics unit. Furthermore, when the recovered energy generated by the motor exceeds the storage capacity of the power electronics unit, the recovered energy is difficult to dissipate through the power electronics unit. This may lead to a short circuit, which could damage or malfunction the motor and other components of the electric vehicle.

[0004] Therefore, in view of the above problems, there is a need to provide a transmission system that can eliminate one or more of the aforementioned problems associated with existing transmission systems. Summary of the Invention

[0005] This summary is provided to introduce a series of concepts in a simplified form, which will be further described in specific embodiments of the invention. This summary is not intended to identify key or essential inventive concepts of the invention, nor is it intended to define the scope of the invention.

[0006] This disclosure discloses a drivetrain for an electric vehicle. The drivetrain may include a drive control unit, a one-way clutch assembly, a friction clutch assembly, and a bypass mechanism. The drive control unit is adapted to determine vehicle speed and throttle position based on inputs received from multiple 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 an input shaft and operatively coupled to a second gear drive and a first gear drive. The bypass mechanism is adapted to bypass the one-way clutch assembly. The drive control unit is adapted to activate at least the bypass mechanism and disengage the friction clutch assembly based on vehicle speed and throttle position to limit power transmission from the output shaft to the input shaft.

[0007] Furthermore, this disclosure discloses a drivetrain for an electric vehicle. The drivetrain may include a drivetrain control unit, a first clutch assembly, and a second clutch assembly. The drivetrain control unit is adapted to determine vehicle speed and throttle position based on inputs received from multiple 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 an input shaft and operatively coupled to a second gear drive. The drivetrain control unit is adapted to disengage at least the first and second clutch assemblies based on vehicle speed and throttle position to limit power transmission from the output shaft to the input shaft.

[0008] Furthermore, this disclosure discloses a method for controlling a drivetrain system of an electric vehicle. The method may include: determining vehicle speed and throttle position via a drivetrain control unit based on inputs received from multiple sensors mounted on the vehicle. The method may include deactivating at least one of the following via the drivetrain control unit: deactivating a first clutch assembly operatively coupled to a first gear drive to limit power transmission from the output shaft to the input shaft when the throttle position and vehicle speed are respectively less than a predetermined throttle position and a predetermined vehicle speed; and deactivating a second clutch assembly operatively coupled to a second gear drive to limit power transmission from the output shaft to the input shaft when the throttle position and vehicle speed are respectively greater than a predetermined throttle position and a predetermined vehicle speed.

[0009] To further illustrate the advantages and features of this disclosure, the invention will be described in more detail with reference to specific embodiments illustrated in the accompanying drawings. It is to be understood that these drawings depict only typical embodiments of the invention and are therefore not intended to limit the scope of the invention. The invention will be described and explained with reference to the accompanying drawings, including additional features and details. Attached Figure Description

[0010] These and other features, aspects, and advantages of this disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings, throughout which the same reference numerals denote the same parts: Figure 1 A partial schematic diagram of an electric vehicle according to an embodiment of the present disclosure is shown; Figure 2 The diagram illustrates a block diagram depicting a transmission control unit of an electric vehicle according to an embodiment of the present disclosure. Figures 3(a), 3(b) and 3(c) illustrate schematic diagrams of the transmission system of an electric vehicle according to an embodiment of the present disclosure; Figure 4(a) illustrates a schematic diagram of a transmission system having a friction clutch assembly and a one-way clutch (OWC) assembly and a bypass mechanism according to an embodiment of the present disclosure. Figure 4(b) illustrates a flowchart depicting the operation of the transmission system of Figure 4(a) according to an embodiment of the present disclosure; Figure 5(a) illustrates a schematic diagram of a transmission system having a friction clutch assembly and a one-way clutch (OWC) assembly without a bypass mechanism according to an embodiment of the present disclosure. Figure 5(b) illustrates a flowchart depicting the operation of the transmission system of Figure 5(a) according to an embodiment of the present disclosure; Figure 6(a) illustrates a schematic diagram of a transmission system having a 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 the operation of the transmission system of Figure 6(a) according to an embodiment of the present disclosure; and Figure 7 The illustration shows a flowchart depicting a method for controlling a transmission system according to an embodiment of the present disclosure.

[0011] Furthermore, those skilled in the art will understand that the elements in the accompanying drawings are illustrated for simplicity and may not necessarily be drawn to scale. For example, the flowcharts illustrate the method according to the most important steps involved to aid in understanding various aspects of this disclosure. Additionally, regarding the construction of the apparatus, one or more components may have been represented by conventional symbols in the drawings, and the drawings may only show those specific details relevant to understanding embodiments of this disclosure, so as not to obscure the drawings due to details that would be obvious to those of ordinary skill in the art who would benefit from the description herein. Detailed Implementation

[0012] For the purpose of promoting an understanding of the principles of the invention, the embodiments illustrated in the accompanying drawings will now be described using specific language. However, it will be understood that this is not intended to limit the scope of the invention, and these changes and further modifications to the illustrated systems, as well as these further applications of the principles of the invention described herein, are contemplated as would normally occur to those skilled in the art to which this invention pertains. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The systems, methods, and examples provided herein are illustrative only and are not intended to be limiting.

[0013] The term "some" as used herein is defined as "none, or one, or more than one, or all". Therefore, the terms "", "one", "more than one", "more than one but not all", or "all" all fall under the limitation of "some". The term "some embodiments" can refer to no embodiments, one embodiment, several embodiments, or all embodiments. Therefore, the term "some embodiments" is limited to meaning "no embodiments, or one embodiment, or more than one embodiment, or all embodiments".

[0014] The terminology and structure used herein are intended to describe, teach, and clarify certain embodiments and their specific features and elements, and are not intended to limit, constrain, or diminish the spirit and scope of the claims or their equivalents.

[0015] More specifically, any term used herein, such as but not limited to “including,” “contains,” “has,” “contains,” and its grammatical variations, does not specify any exact limitation or constraint, and certainly does not preclude the possibility of adding one or more features or elements unless otherwise stated, and furthermore, unless otherwise stated by the restrictive language “must include” or “requires inclusion,” it shall not be regarded as excluding the possibility of removing one or more of the listed features and elements.

[0016] Regardless of whether a feature or element is limited to being used only once, 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" features or elements does not preclude the absence of that feature or element, unless otherwise specified by restrictive language such as "one or more must be present..." or "one or more elements are required."

[0017] Unless otherwise specified, all terms used herein, and in particular any technical and / or scientific terms, shall be deemed to have the same meaning as commonly understood by one of ordinary skill in the art.

[0018] Reference has been made to several “implementations” herein. It should be understood that an implementation refers to examples of possible ways of implementing any feature and / or element set forth in the appended claims. Several implementations have been described for the purpose of elucidating one or more potential ways of satisfying the requirements of unity, utility, and non-obviousness of the specific features and / or elements of the appended claims.

[0019] The use of phrases and / or terms such as, but not limited to, “first embodiment,” “another embodiment,” “alternative embodiment,” “one embodiment,” “implementation,” “multiple embodiments,” “some embodiments,” “other embodiments,” “yet another embodiment,” “further embodiments,” “another embodiment,” or variations thereof, does not necessarily refer to the same embodiment. Unless otherwise stated, one or more specific features and / or elements described in conjunction with one or more embodiments may be found in one embodiment, or in more than one embodiment, or in all embodiments, or not in any embodiment. Although one or more features and / or elements may be described herein only in the context of a single embodiment, or alternatively in the context of more than one embodiment, or further alternatively in the context of all embodiments, such features and / or elements may alternatively be provided individually or in any suitable combination, or not at all. Conversely, any features and / or elements described in the context of a single embodiment may alternatively be implemented as existing together in the context of a single embodiment.

[0020] Any specific details set forth herein, and all details thereof, are used in the context of some implementations and therefore should not be considered limiting factors of the appended claims. The appended claims and their legal equivalents may be implemented in the context of implementations other than those used as illustrative examples in the following description.

[0021] The embodiments of this disclosure will now be described in detail with reference to the accompanying drawings.

[0022] Figure 1 The illustration shows a partial schematic diagram of electric vehicle 200, while Figure 2 The diagram illustrates a block diagram depicting the transmission control unit 102 of an electric vehicle 200. (Refer to...) Figure 1 , Figure 2 The electric vehicle 200 may include a drivetrain 100 and a motor 210 connected to the drivetrain 100. The motor 210 is powered by a battery 202 through various converters, such as a DC-DC converter 206 and an inverter 208. Furthermore, the electric vehicle 200 may include a vehicle control unit (VCU) 212 and a transmission control unit (TCU) 102. The VCU 212 is electrically connected to the TCU 102 to provide control signals to the TCU 102. Additionally, the VCU 212 and the TCU 102 may be connected to a battery management system (BMS) 204 in which the battery 202 is located.

[0023] The motor 210 can operate as both an electric motor and a generator based on control signals from the VCU 212. In one example, the motor 210 can operate as a motor 210 during the normal mode of the electric vehicle 200. In another example, the motor 210 can operate as a generator during regenerative braking of the electric vehicle 200 or in its recovery mode to charge the battery 202. Here, the drivetrain 100 is coupled to multiple wheels 214 of the electric vehicle 200.

[0024] VCU 212 may include, but is not limited to, a tilt sensor, a throttle position sensor 222, an ignition switch, a brake input device, and a reverse input device. VCU 212 may communicate with TCU 102. TCU 102 may be configured to control the transmission system 100 based on commands received from VCU 212. TCU 102 may be connected to multiple sensors, such that TCU 102 may be adapted to determine vehicle speed and throttle position based on inputs received from multiple sensors mounted on the electric vehicle 200. The multiple sensors may include, but are not limited to, a vehicle speed sensor 216, a clutch position sensor 220, and a one-way clutch (OWC) bypass position sensor 218. TCU 102 may be connected to an indicator unit 224, which is adapted to display one of a transmission mode indication, a clutch status indication, and a reverse indication based on inputs received from TCU 102. Furthermore, TCU 102 may be connected to a friction clutch actuator 226 and an OWC bypass actuator 228.

[0025] Figures 3(a), 3(b), and 3(c) illustrate schematic diagrams of the drivetrain 100 of an electric vehicle 200. Referring to Figures 3(a), 3(b), and 3(c), the drivetrain 100 can be adapted for installation in the electric vehicle 200. The drivetrain 100 may include an input shaft 104, an output shaft 106, a differential 108, a TCU 102, a first clutch assembly, and a second clutch assembly. In this document, without departing from the scope of this disclosure, the first clutch assembly may be implemented as one of a one-way clutch (OWC) assembly 110 and a friction clutch assembly 112. Furthermore, without departing from the scope of this disclosure, the second clutch assembly may be implemented as one of an OWC assembly 110 and a friction clutch assembly 112.

[0026] The first and second clutch assemblies are adapted to engage the input shaft 104 with the output shaft 106 to transmit torque. The input shaft 104 may be adapted to drive a differential 108 via the output shaft 106. The differential 108 may drive the axles of the electric vehicle 200. The input shaft 104 may be coupled to a motor 210 to receive torque. The differential 108 may be adapted to transmit torque to multiple wheels 214 of the electric vehicle 200. In an embodiment, the differential 108 may be a double-crown differential.

[0027] In the illustrated embodiment, as shown in FIG. 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 FIG. 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 yet another embodiment, referring to FIG. 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. Hereinafter, the first gear drive 114 may include a first gear set, and the second gear drive 116 may include a second gear set.

[0028] TCU 102 can be adapted to determine vehicle speed and throttle position based on inputs received from multiple sensors, such as vehicle speed sensor 216 and throttle position sensor 222. Herein, vehicle speed sensor 216 can be adapted to determine the speed of electric vehicle 200. Throttle position sensor 222 is adapted to determine the throttle position of electric vehicle 200. TCU 102 is adapted to disengage at least the first and second clutch assemblies based on vehicle speed and throttle position to limit power transmission from output shaft 106 to input shaft 104. Therefore, even in regeneration mode, power transmission from output shaft 106 to input shaft 104 can be limited. This prevents damage or malfunction of the power electronics unit because there is no need to dissipate power through the power electronics unit.

[0029] TCU 102 can be adapted to determine whether the throttle position is less than or greater than a predetermined throttle position. Furthermore, TCU 102 can be adapted to determine whether the vehicle speed is less than or greater than a predetermined vehicle speed. In this document, the predetermined throttle position can define the throttle position at which the switching from the first gear drive 114 to the second gear drive 116 is performed. The predetermined vehicle speed can define the vehicle speed at which the switching from the first gear drive 114 to the second gear drive 116 is performed.

[0030] TCU 102 can be adapted to disengage one of the first clutch assembly and the second clutch assembly to limit transmission through the first gear drive 114 and the second gear drive 116, respectively. When the vehicle speed and throttle position are less than a predetermined vehicle speed and a predetermined throttle position, respectively, TCU 102 can disengage the first clutch assembly to limit power transmission from the output shaft 106 through the first gear drive 114 to the input shaft 104. Furthermore, when the vehicle speed and throttle position are greater than a predetermined vehicle speed and a predetermined throttle position, respectively, TCU 102 can disengage the second clutch assembly to limit power transmission from the output shaft 106 through the second gear drive 116 to the input shaft 104.

[0031] Figure 4(a) illustrates a schematic diagram of a transmission system 100 having a friction clutch assembly 112 and an OWC assembly 110 and a bypass mechanism 118, while Figure 4(b) illustrates a flowchart depicting the operation of the transmission system 100 of Figure 4(a). Referring to Figure 4(a), a first clutch assembly is implemented as operatively coupled to the OWC assembly 110 of a first gear drive 114, and a second clutch assembly is implemented as operatively coupled to the friction clutch assembly 112 of a second gear drive 116. In this document, the transmission system 100 may include a TCU 102, an OWC assembly 110, a friction clutch assembly 112, and a bypass mechanism 118.

[0032] TCU 102 may be adapted to determine vehicle speed and throttle position based on inputs received from multiple sensors mounted on vehicle 200. The multiple sensors may include a vehicle speed sensor 216 and a throttle position sensor 222. OWC assembly 110 may be adapted to be mounted on input shaft 104 and operatively coupled to a first gear drive 114. Friction clutch assembly 112 may be adapted to be mounted on input shaft 104 and operatively coupled to a second gear drive 116 and a first gear drive 114. Bypass mechanism 118 may be adapted to bypass OWC assembly 110. TCU 102 may be adapted to activate at least bypass mechanism 118 and disengage friction clutch assembly 112 based on vehicle speed and throttle position to limit power transmission from output shaft 106 to input shaft 104.

[0033] The bypass mechanism 118 may include a reverse ratchet actuator unit adapted to be actuated to slide the OWC component 110. Therefore, the bypass mechanism 118 can be enabled to slide the OWC component 110, thereby restricting the power transmission from the output shaft 106 to the input shaft 104.

[0034] Referring to Figure 4(b), at box 402, a motor, such as motor 210, can be activated to supply power to move the electric vehicle 200. Furthermore, at box 404, the TCU 102 can determine whether the throttle position is less than or greater than a predetermined throttle position (UPS throttle %). If the throttle position is less than the predetermined throttle position (UPS throttle %), operation of the transmission system 100 proceeds to box 406. Alternatively, if the throttle position is greater than the predetermined throttle position, operation proceeds to box 408.

[0035] At box 406, TCU 102 determines whether the vehicle speed is less than or greater than a predetermined vehicle speed. If the vehicle speed is less than the predetermined vehicle speed (UPS vehicle speed), the operation of TCU 100 proceeds to box 410. Alternatively, if the vehicle speed is greater than the predetermined vehicle speed (UPS vehicle speed), the operation proceeds to box 408. Furthermore, at box 410, TCU 102 actuates the reverse ratchet actuator unit of OWC component 110. At box 412, TCU 102 checks whether OWC bypass mechanism 118 is enabled. If OWC bypass mechanism 118 is not enabled, the operation moves back to box 410. Alternatively, if OWC bypass mechanism 118 is enabled, OWC component 110 is deactivated and the operation proceeds to another box 414.

[0036] At block 414, the friction clutch actuator 226 is engaged, and operation proceeds to block 416. At block 416, TCU 102 can check whether the friction clutch assembly 112 is fully engaged based on the input of the clutch position sensor 220. If the friction clutch assembly 112 is not fully engaged, operation returns to block 414. Alternatively, if the friction clutch assembly 112 is fully engaged, operation proceeds to block 418. At block 418, the friction clutch actuator 226 is disengaged, and operation proceeds to block 420. At block 420, power transmission from output shaft 106 to input shaft 104 via first gear drive 114 is limited based on vehicle speed and throttle position.

[0037] At box 408, TCU 102 determines whether the throttle position is greater than the predetermined throttle position (UPS throttle %) and whether the vehicle speed is greater than the predetermined vehicle speed (UPS vehicle speed). If so, the operation proceeds to box 422. At box 422, friction clutch actuator 226 opens, and the operation proceeds to box 424.

[0038] At block 424, TCU 102 can check whether the friction clutch assembly 112 is fully engaged based on the input of the clutch position sensor 220. If the friction clutch assembly 112 is not fully engaged, operation returns to block 422. Alternatively, if the friction clutch assembly 112 is fully engaged, operation proceeds to block 426. At block 426, the friction clutch actuator 226 is deactivated, and operation proceeds to block 428. At block 428, power transmission from output shaft 106 to input shaft 104 via second gear drive 116 is limited based on vehicle speed and throttle position.

[0039] Figure 5(a) illustrates a schematic diagram of a transmission system 100 having a friction clutch assembly 112 and an OWC assembly 110 without bypassing mechanism 118, while Figure 5(b) illustrates a flowchart depicting the operation of the transmission system 100 of Figure 5(a). Referring to Figure 5(a), a first clutch assembly is implemented as operatively coupled to the OWC assembly 110 of a first gear drive 114, and a second clutch assembly is implemented as operatively coupled to the friction clutch assembly 112 of a second gear drive 116. In this document, the transmission system 100 may include a TCU 102, an OWC assembly 110, and a friction clutch assembly 112.

[0040] Referring to Figure 5(b), at block 502, a motor, such as motor 210, can be activated to supply power to move the electric vehicle 200. Furthermore, at block 504, the TCU 102 can determine whether the throttle position is less than or greater than a predetermined throttle position (UPS throttle %). If the throttle position is less than the predetermined throttle position (UPS throttle %), operation of the transmission system 100 proceeds to block 506. Alternatively, if the throttle position is greater than the predetermined throttle position, operation proceeds to block 508.

[0041] At block 506, TCU 102 determines whether the vehicle speed is less than or greater than a predetermined vehicle speed. If the vehicle speed is less than the predetermined vehicle speed (UPS vehicle speed), the operation of TCU 100 proceeds to block 510. Alternatively, if the vehicle speed is greater than the predetermined vehicle speed (UPS vehicle speed), the operation proceeds to block 508. Furthermore, at block 510, OWC component 110 can slide, and operation proceeds to another block 512. At block 512, the power transmission from output shaft 106 to input shaft 104 via first gear drive 114 is limited based on vehicle speed and throttle position.

[0042] At block 508, TCU 102 can determine whether the throttle position is greater than a predetermined throttle position (UPS throttle %) and whether the vehicle speed is greater than a predetermined vehicle speed (UPS vehicle speed). If so, the operation proceeds to block 514. At block 514, friction clutch actuator 226 is engaged, and the operation proceeds to block 516. At block 516, TCU 102 can check whether friction clutch assembly 112 is fully engaged based on the input of clutch position sensor 220. If friction clutch assembly 112 is not fully engaged, the operation returns to block 514. Alternatively, if friction clutch assembly 112 is fully engaged, the operation proceeds to block 518. At block 518, friction clutch actuator 226 is disengaged, and the operation proceeds to block 520. At block 520, power transmission from output shaft 106 to input shaft 104 via second gear drive 116 is limited based on vehicle speed and throttle position.

[0043] Figure 6(a) illustrates a schematic diagram of a transmission system 100 having a first friction clutch assembly and a second friction clutch assembly, while Figure 6(b) illustrates a flowchart depicting the operation of the transmission system 100 of Figure 6(a). Referring to Figure 6(a), the first clutch assembly can be implemented as a first friction clutch assembly operatively coupled to a first gear drive 114, and the second clutch assembly can be implemented as a first friction clutch assembly operatively coupled to a second gear drive 116. The first friction clutch assembly is coupled with a first friction clutch actuator, and the second friction clutch assembly is coupled with a second friction clutch actuator. In this document, the first friction clutch assembly and the second friction clutch assembly can be collectively referred to as the dual friction clutch assembly 112.

[0044] Referring to Figure 6(b), at block 602, a motor, such as motor 210, can be activated to supply power to move the electric vehicle 200. Furthermore, at block 604, the TCU 102 can determine whether the throttle position is less than or greater than a predetermined throttle position (UPS throttle %). If the throttle position is less than the predetermined throttle position (UPS throttle %), operation of the transmission system 100 proceeds to block 606. Alternatively, if the throttle position is greater than the predetermined throttle position, operation proceeds to block 608.

[0045] At block 606, TCU 102 determines whether the vehicle speed is less than or greater than a predetermined vehicle speed. If the vehicle speed is less than the predetermined vehicle speed (UPS vehicle speed), the operation of TCU 100 proceeds to block 610. Alternatively, if the vehicle speed is greater than the predetermined vehicle speed (UPS vehicle speed), the operation proceeds to block 608. Furthermore, at block 610, the first friction clutch actuator opens, and the operation proceeds to block 612. At block 612, TCU 102 can check whether the friction clutch assembly 112 is fully engaged based on the input of the clutch position sensor 220. If the friction clutch assembly 112 is fully engaged, the operation proceeds to block 614. At block 614, the first friction clutch actuator closes, and the operation proceeds to block 616. At block 616, the power transmission from output shaft 106 to input shaft 104 via first gear drive 114 is limited based on vehicle speed and throttle position.

[0046] At block 608, TCU 102 can determine whether the throttle position is greater than a predetermined throttle position (UPS throttle %) and whether the vehicle speed is greater than a predetermined vehicle speed (UPS vehicle speed). If so, the operation proceeds to block 618. At block 618, the second friction clutch actuator opens, and the operation proceeds to block 620. At block 620, TCU 102 can check whether the friction clutch assembly 112 is fully engaged based on the input of the clutch position sensor 220. If the friction clutch assembly 112 is not fully engaged, the operation returns to block 618. Alternatively, if the friction clutch assembly 112 is fully engaged, the operation proceeds to block 622. At block 622, the second friction clutch actuator closes, and the operation proceeds to block 624. At block 624, the power transmission from output shaft 106 to input shaft 104 via second gear drive 116 is limited based on vehicle speed and throttle position.

[0047] This disclosure also relates to a method for controlling the transmission system 100 of an electric vehicle 200, such as... Figure 7 As shown in the diagram. The order of the method steps described below is not intended to be construed as limiting, but rather that any number of the method steps can be combined in any suitable order to perform the method or an alternative method. Furthermore, individual steps may be omitted from the method without departing from the spirit and scope of the subject matter described herein.

[0048] Furthermore, this disclosure discloses a method 700 for controlling a drivetrain 100 of an electric vehicle 200. The method begins at step 702, in which the vehicle speed and throttle position can be determined by the TCU 102 based on inputs received from multiple sensors mounted on the vehicle 200. Hereinafter, the multiple sensors may include a vehicle speed sensor 216 and a throttle position sensor 222. The vehicle speed sensor 216 can determine the vehicle speed and transmit an input indicating the vehicle speed to the TCU 102. Similarly, the throttle position sensor 222 can determine the throttle position of the electric vehicle and transmit an input indicating the throttle position to the TCU 102.

[0049] Furthermore, at step 704, the method may include deactivating at least one of the first clutch assembly and the second clutch assembly via TCU 102. Herein, the first clutch assembly may be deactivated when the throttle position and vehicle speed are less than a predetermined throttle position and a predetermined vehicle speed, respectively, to limit power transmission from output shaft 106 to input shaft 104. Furthermore, the second clutch assembly may be deactivated when the throttle position and vehicle speed are greater than a predetermined throttle position and a predetermined vehicle speed, respectively, to limit power transmission from output shaft 106 to input shaft 104.

[0050] The drivetrain 100 includes a TCU 102, a bypass mechanism 118, an OWC assembly 110, and a friction clutch assembly 112. Herein, the TCU 102 can activate the bypass mechanism 118 and deactivate the friction clutch assembly 112 based on vehicle speed and throttle position. Activation of the bypass mechanism 118 can cause the OWC assembly 110 to slip or deactivate. Deactivation of the OWC assembly 110 and the friction clutch assembly 112 can limit power transmission from the output shaft 106 to the input shaft 104. Therefore, even in regeneration mode, power transmission from the output shaft 106 to the input shaft 104 can be limited. This prevents damage or malfunction of the power electronics unit because there is no need to dissipate power through the power electronics unit. Furthermore, the overall efficiency and operation of the motor are improved by avoiding short circuits caused by excessive power.

[0051] In another embodiment, the transmission system 100 includes a TCU 102, an OWC assembly 110, and a friction clutch assembly 112. The TCU 102 can disengage the OWC assembly 110 and the friction clutch assembly 112 based on vehicle speed and throttle position to limit power transmission from the output shaft 106 to the input shaft 104. Disengagement of the OWC assembly 110 and the friction clutch assembly 112 can limit power transmission from the output shaft 106 to the input shaft 104.

[0052] Furthermore, in one embodiment, the transmission system 100 includes a TCU 102, a first friction clutch assembly, and a second friction clutch assembly. The TCU 102 can disengage the first and second friction clutch assemblies based on vehicle speed and throttle position to limit power transmission from the output shaft 106 to the input shaft 104. Disengagement of the first and second friction clutch assemblies can limit power transmission from the output shaft 106 to the input shaft 104.

[0053] Although specific language has been used to describe the subject matter, it is not intended to impose any limitations. As will be apparent to those skilled in the art, various feasible modifications can be made to the method to achieve the inventive concept as taught herein. The accompanying drawings and the foregoing description provide examples of embodiments. It will be understood by those skilled in the art that one or more of the described elements can be well combined into a single functional element. Alternatively, certain elements may be divided into multiple functional elements. Elements from one embodiment may be added to another embodiment.

Claims

1. A drive system (100) for an electric vehicle (200), the drive system (100) comprising: Transmission control unit (102), the transmission control unit being adapted to determine vehicle speed and throttle position based on inputs received from multiple 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), which is mounted on the input shaft (104) and operatively coupled to a second gear drive (116) and a first gear drive (114); and Bypass mechanism (118), the bypass mechanism being adapted to bypass the one-way clutch assembly (110). The transmission control unit (102) is adapted to activate at least the bypass mechanism (118) and disengage the friction clutch assembly (112) based on the vehicle speed and the throttle position to limit the power transmission from the output shaft (106) to the input shaft (104).

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

3. The transmission system (100) according to claim 2, wherein: The predetermined throttle position defines the throttle position at which the switching from the first gear drive (114) to the second gear drive (116) is performed; and The predetermined vehicle speed defines the vehicle speed at which the switching from the first gear drive (114) to the second gear drive (116) is performed.

4. The transmission system (100) according to claim 2, wherein, The transmission control unit (102) is adapted to actuate the bypass mechanism (118) and disengage the friction clutch assembly (112) when the vehicle speed and the throttle position are less than the predetermined vehicle speed and the predetermined throttle position, respectively, to limit the power transmission from the output shaft (106) through the first gear drive (114) to the input shaft (104).

5. The transmission system (100) according to claim 2, wherein, The transmission control unit (102) is adapted to disengage the friction clutch assembly (112) when the vehicle speed and the throttle position are greater than the predetermined vehicle speed and the predetermined throttle position, respectively, to limit the power transmission from the output shaft (106) through the second gear drive (116) to the input shaft (104).

6. The transmission system (100) according to 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) when the vehicle speed and the throttle position are less than the predetermined vehicle speed and the predetermined throttle position, respectively, to limit the power transmission from the output shaft (106) to the input shaft (104).

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

8. A drive system (100) for an electric vehicle (200), the drive system (100) comprising: A transmission control unit (102) is adapted to determine vehicle speed and throttle position based on inputs received from multiple sensors mounted on the vehicle (200); as well as 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 is adapted to be mounted on the input shaft (104) and operatively coupled to a second gear drive (116). and The transmission control unit (102) is adapted to disengage at least the first clutch assembly and the second clutch assembly based on the vehicle speed and the throttle position to limit power transmission from the output shaft (106) to the input shaft (104).

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

10. The transmission system (100) according to claim 9, wherein: The predetermined throttle position defines the throttle position at which the switching from the first gear drive (114) to the second gear drive (116) is performed; and The predetermined vehicle speed defines the vehicle speed at which the switching from the first gear drive (114) to the second gear drive (116) is performed.

11. The transmission system (100) according to claim 8 or 9, wherein, The transmission control unit (102) is adapted to disengage the first clutch assembly when the vehicle speed and the throttle position are less than the predetermined vehicle speed and the predetermined throttle position, respectively, to limit the power transmission from the output shaft (106) through the first gear drive (114) to the input shaft (104).

12. The transmission system (100) according to claim 8 or 9, wherein, The transmission control unit (102) is adapted to disengage the second clutch assembly when the vehicle speed and the throttle position are greater than the predetermined vehicle speed and the predetermined throttle position, respectively, to limit the power transmission from the output shaft (106) through the second gear drive (116) to the input shaft (104).

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

14. The transmission system (100) according to claim 8. in, The first clutch assembly is implemented as a first friction clutch assembly (112) operatively coupled to the first gear drive (114); and The second clutch assembly is implemented 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: The transmission control unit (102) determines (702) the vehicle speed and throttle position based on inputs received from multiple sensors mounted on the vehicle (200); The transmission control unit (102) deactivates at least one of the following (704): The first clutch assembly operatively coupled to the first gear drive (114) is deactivated to limit power transmission from the output shaft (106) to the input shaft (104) when the throttle position and the vehicle speed are less than the predetermined throttle position and the predetermined vehicle speed, respectively. as well as The second clutch assembly, operatively connected to the second gear drive (116), is deactivated to limit power transmission from the output shaft (106) to the input shaft (104) when the throttle position and the vehicle speed are greater than the predetermined throttle position and the predetermined vehicle speed, respectively.

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