Description:POWER MANAGEMENT SYSTEM FOR VEHICLE

TECHNICAL FIELD
[0001] The present disclosure pertains to the field of vehicular power management. More specifically, controlling electric motor operations in a vehicle using throttle inputs and rotational speed determinations to optimize power consumption and driving experience.
BACKGROUND
[0002] With the rapid advancements in technology and growing concerns about environmental sustainability, electric vehicles (EVs) have emerged as a frontrunner in the quest for cleaner and more efficient modes of transportation. Unlike their internal combustion engine (ICE) counterparts, EVs operate using electric motors, offering an array of benefits including reduced emissions, lower operational costs, and a quieter ride. However, with the merits also come challenges, especially in relation to the primary vehicle control mechanisms – the throttle and brakes.
[0003] For any vehicle, irrespective of its power source, the throttle represents an essential control interface between the rider and the powertrain of the vehicle. The perception of the rider of responsiveness, predictability, and overall performance of vehicle largely stems from the feedback received from the throttle. As such, an optimal throttle response that aligns seamlessly with the intrinsic nature of the vehicle is a paramount objective for automotive engineers.
[0004] The modus operandi of the throttle, particularly its response, varies substantially between ICE vehicles and electric vehicles. The disparity arises from the fundamental differences in the underlying physics, energy conversion processes, and architectural configurations that govern the two powertrain types.
[0005] In vehicles powered by internal combustion engines, the throttle serves a dual role, enabling the rider to accelerate and decelerate the vehicle. The engine braking phenomenon is inherently rooted in the physics of ICE operation. When a rider reduces throttle input, leads to reduced power output, naturally slowing the vehicle down. Moreover, ICE vehicles afford riders the ability to maintain a steady speed, or cruise, by holding the throttle in a consistent position. The cruising capability, combined with the braking property of the engine, grants riders a sense of control and predictability. Furthermore, in cruise state acceleration is almost linear to maintain speed
[0006] Conversely, electric vehicles, characterized by the electric motors, exhibit distinct operational traits. Electric motors are renowned for the ability to provide immediate torque upon demand, leading to swift acceleration. Such attributes, while beneficial in scenarios demanding rapid speed increases, can sometimes be perceived as overly aggressive or unpredictable by riders accustomed to the perceived gradual acceleration curve of ICE vehicles. While electric motors lack inherent engine braking like ICEs, they possess the capability to emulate the deceleration effect through regenerative braking. The system harnesses the motor as a generator during deceleration phases, converting kinetic energy back into stored electrical energy, thereby slowing the vehicle and augmenting battery efficiency.
[0007] Given such disparities in operational characteristics, there emerges a palpable need to bridge the gap between the rider’s experiences of ICE and electric powertrains. While electric vehicles promise a future of sustainability and efficiency, ensuring a riding experience that mirrors the familiarity, control, and comfort of traditional vehicles becomes paramount. By enhancing the predictability of throttle responses and integrating features that mimic the nuanced control of ICE vehicles, there is a probability to elevate the overall riding experience of EVs. Such integrations would strengthen rider confidence and also play a pivotal role in accelerating the global transition to electric mobility. The quest, therefore, is to innovate and devise systems within the electric vehicle domain that amalgamate the best of both worlds, merging the environmental benefits of EVs with the tried-and-tested control dynamics of ICE vehicles.
SUMMARY
[0008] The aim of the present disclosure is to provide a power management system for a vehicle to control vehicular operations based on a Input provide by rider/driver, current state of the vehicle powertrain, speed of the vehicle and the external resistances acting against the vehicle vehicle. The aim of the disclosure is achieved by a power management system for a vehicle for controlling vehicular operations.
[0009] The disclosure relates to a power management system for a vehicle, the system comprising: a battery pack to supply an operating electric current to an electric motor; a sensing unit determines: a rotational speed associated with the electric motor, wherein the rotational speed corresponds to the supplied operating electric current; and a throttle input; and a vehicle control unit (VCU): receives the throttle input and the rotational speed; calculates a required velocity based on the received throttle input; computes the difference between the calculated required velocity and the determined rotational speed; calculate a requested electric current based on the received throttle input; select a driving state based on the computed difference, wherein the driving state controls an operation of the motor, and wherein the driving state is selected from: a traction state if the computed difference is positive and greater than a positive threshold value; a cruise state if the computed difference is lesser than the positive threshold value and greater than a negative threshold value; and a regeneration state if the computed difference is lesser than the negative threshold value.
[0010] In an embodiment, in the traction state, the VCU utilizes a throttle position vs power multiplier map to calculate a demanded electric current from the electric motor.
[0011] In an embodiment, the VCU allows a motor controller to draw the calculated demanded electric current from the battery, if the requested electric current is lesser than an electric current limit imposed by the motor controller.
[0012] In an embodiment, the VCU allows the motor controller to draw a limited electric current, if the requested electric current is higher than the electric current limit imposed by the motor controller.
[0013] In an embodiment, in the cruise state, the VCU calculates an initial electric current value required to maintain the requested velocity based on a requested velocity vs constant electric current table.
[0014] In an embodiment, in the cruise state, the VCU adjusts the supplied operating electric current to maintain the required velocity.
[0015] In an embodiment, the VCU in the regeneration state selects, based on the current rotational speed, a regen torque from a regen torque vs vehicle velocity table.
[0016] In an embodiment, the VCU calculates a regen current limit based on the selected regen torque, wherein if the calculated regen current limit is higher than a maximum current corresponding to a maximum torque set by the regen torque vs electric motor rpm table on the motor controller, then the maximum current is limited by the motor controller.
[0017] In an embodiment, if the calculated regen current limit is lower than the maximum current corresponding to the maximum torque set by the regen torque vs electric motor rpm table on the motor controller, then the regen current is supplied to the motor.
[0018] In an embodiment, the regen current limit is associated with a regen current multiplier, wherein the regen current multiplier is adjusted based on the throttle input.
[0019] In an embodiment, the VCU determines a requirement of a transition in the driving state from a first driving state and the second driving state, based on the calculated required velocity.
[0020] In an embodiment, the change in driving state is associated with ramping down or ramping up the operating electric current supplied to the electric motor till the required velocity is achieved, wherein the ramping down or the ramping up the operating electric current initiates if the determined rotational speed exceeds a pre-set threshold value.
[0021] In an embodiment, transitioning the driving state of the vehicle from the traction state to the cruise state comprises linearly ramping down the operating electric current till the cruise state is achieved.
[0022] In an embodiment, transitioning the driving state of the vehicle from the regeneration state to the cruise state comprises linearly ramping up the operating electric current till the cruise state is achieved.
BRIEF DESCRIPTION OF THE DRAWINGS
[0023] The summary above, as well as the following detailed description of illustrative embodiments, is better understood when read in conjunction with the appended drawings. For the purpose of illustrating the present disclosure, exemplary constructions of the disclosure are shown in the drawings. However, the present disclosure is not limited to specific methods and instrumentalities disclosed herein.
[0024] Embodiments of the present disclosure will now be described, by way of example only, with reference to the following diagrams.
[0025] FIG. 1 illustrates a power management system for a vehicle, in accordance with embodiments of the present disclosure;
[0026] FIG. 2 illustrates a method for managing power management of a vehicle, in accordance with embodiments of the present disclosure;
[0027] FIG. 3 illustrates a vehicle-rider interaction diagram, in accordance with embodiments of the present disclosure;
[0028] FIG. 4 illustrates a throttle response diagram, in accordance with embodiments of the present disclosure.
DETAILED DESCRIPTION OF EMBODIMENTS
[0029] The following detailed description illustrates embodiments of the present disclosure and ways in which they can be implemented. Although some modes of carrying out the present disclosure have been disclosed, those skilled in the art would recognize that other embodiments for carrying out or practicing the present disclosure are also possible.
[0030] FIG. 1 illustrates a power management system 100 (interchangeably referred as system 100) for a vehicle, in accordance with embodiments of the present disclosure. The power management system for a vehicle 100 comprises a battery pack 102, an electric motor 104, a sensing unit 106, a vehicle control unit (VCU) 108 and other known components of a vehicle (particularly electric vehicle).
[0031] In an embodiment, the battery pack 102 is configured to store electrical energy essential for various vehicle operations. The battery pack 102 is operatively coupled with the electric motor 104 to convert the electrical energy received from the battery pack 102 into mechanical energy, thereby propelling the vehicle. The battery pack 102 is adapted to supply an operating electric current to the electric motor 104. The flow of the operating electric current from said battery pack 102 to said electric motor 104 is optimized to ensure efficient vehicle performance. Further, safety mechanisms can be integrated to regulate the electric current supply, preventing overloads or shorts. The interface between said battery pack 102 and said electric motor 104 is robust, ensuring consistent energy transfer under various operating conditions. In doing so, the power management system 100 seeks to achieve seamless integration and operation between said battery pack 102 and said electric motor 104, enhancing the overall performance and reliability of the vehicle.
[0032] In one embodiment, the sensing unit 106 is configured to determine a rotational speed associated with the electric motor 104. Such rotational speed corresponds to the operating electric current supplied thereto. Furthermore, said sensing unit 106 is also adapted to determine a throttle input related to the vehicle. Through the sensed speed and throttle input, the sensing unit 106 facilitates monitoring and assessing the performance metrics associated with the electric motor 104 to ensure optimal functioning and power management for the vehicle. By detecting both the rotational speed, which corresponds to the electric current, and the throttle input, the system 100 efficiently manages and controls the power distribution within the vehicle, by considering the real-time requirements and conditions. The combination allows the power management system 100 to optimize the performance of vehicle while ensuring energy efficiency.
[0033] In an embodiment, the rotational speed sensor, determines the rotational speed of the electric motor 104, is an integral component in the sensing unit 106. The rotational speed sensor operates by capturing and monitoring the rate at which the shaft of the electric motor 104 spins, providing precise and real-time data on the revolutions per minute (RPM). Employing sensing mechanisms, the rotational speed sensor can detect even minute fluctuations in the speed of electric motor 104, ensuring the responsiveness of system 100 to dynamic operational demands. Furthermore, the feedback from the rotational speed sensor aids in the continuous optimization of the performance of electric motor 104, allowing for the efficient modulation of power and energy conservation. The data relayed by the rotational speed sensor ensures that the electric motor 104 operates within the optimal parameters. Thus, by integrating the rotational speed sensor, the overall efficiency, safety, and longevity of the electric motor 104 are significantly enhanced, enabling a more seamless and efficient driving experience for users.
[0034] In an embodiment, the sensing unit 106 is configured to facilitate the precise measurement and assessment of throttle input in the vehicle. Integrated within the sensing unit 106 is a throttle input sensor, which captures real-time data pertaining to the position throttle and the corresponding input values. Once actuated, the throttle input sensor determines the extent of throttle actuation, translating the mechanical or electronic input from an accelerator pedal of vehicle into quantifiable data. Sensing unit 106 ensures an accurate representation of the intent of driver in terms of acceleration or deceleration. The incorporation of the throttle input sensor into the power management system 100 amplifies the capacity of system 100 to make power distribution and optimization decisions.
[0035] In one embodiment of the present disclosure, the VCU 108 is configured to receive both the throttle input and the rotational speed from the sensing unit 106. VCU 108 utilizes received throttle input and the rotational speed to compute a required velocity. The computational mechanism within said VCU 108 processes the throttle input in conjunction with the received rotational speed to determine the desired vehicular motion parameters. The VCU 108 ensures precision in determining the required velocity for the vehicle, optimizing the performance and responsiveness to the inputs from user.
[0036] In an embodiment, said VCU 108 is interfaced with the sensing unit 106. From sensing unit 106, VCU 108 receives specific operational inputs. Among the inputs, throttle input, indicative of an acceleration demand from the driver, is received by said VCU 108. Concurrently, the rotational speed, which provides data regarding the rotation rate of a shaft or a wheel, within the vehicle, is also channeled to said VCU 108 from the sensing unit 106. By acquiring both the throttle input and the rotational speed, VCU 108 facilitates optimized power management. Through such interfacing and data acquisition processes, the disclosed power management system 100, via said VCU 108, ensures a responsive and adaptive power modulation, aligning the operational dynamics of the vehicle with the commands of the driver and the real-time conditions, thereby promoting efficiency and safety in the performance of the vehicle.
[0037] In an embodiment, VCU 108 is configured to process and determine vehicular dynamics in relation to throttle inputs. Upon receiving specific throttle input data, said VCU 108 undergoes computational operations, enabling the derivation of a required velocity. It is to be understood that the relationship between the throttle input and the resultant required velocity is established through predefined algorithms or mappings housed within VCU 108. By virtue of such algorithms or mappings, a precise and optimized

required velocity is computed, ensuring that the vehicle operates within designated performance and efficiency parameters. The computations performed by such VCU 108 are both dynamic and adaptive, thereby allowing real-time adjustments and responses to varying throttle inputs. The VCU 108 ensures that the power management system 100 effectively translates throttle inputs into appropriate vehicular velocities, optimizing both performance and energy consumption for the vehicle.
[0038] In yet another embodiment, VCU 108 is configured to perform specific computations relating to the operational parameters of the vehicle. VCU 108 involves the calculation of the difference between two distinct parameters: the calculated required velocity and the determined rotational speed. The computed difference serves as a basis for further decisions, adjustments, or actions within the power management system 100. Such functionality ensures optimized performance, increased efficiency, and enhanced reliability of the operation of vehicle.
[0039] In an embodiment, the VCU 108 is adapted to receive throttle input from an associated input device, such as a pedal or lever, indicative of a desire of the driver for acceleration or power. Based upon the received throttle input, said VCU 108 computes a corresponding electric current value. The computed electric current is representative of the power required by the electric motor 104 of the vehicle to satisfy the throttle input. Based on the aforesaid calculation, the powertrain of the vehicle can be optimally managed and controlled, ensuring that the electric motor 104 receives appropriate current to match the desired throttle input. Therefore, VCU 108 performs efficient and effective power management within the vehicle, optimizing both performance and energy consumption based on real-time inputs from the driver. VCU 108 dynamically translates throttle inputs into precise electric current values for efficient power management.
[0040] In another embodiment, said system 100 ascertains driving states based on a computed difference to modulate the performance of an electric motor 104. VCU 108 performs computations to determine the difference, and subsequently, selects an appropriate driving state which directly influences the operational behavior of the electric motor 104.
[0041] Notably, three driving states can be utilized. The first state, referred to as the traction state, is instigated under circumstances where the computed difference, as determined by said VCU 108, is recognized to be positive and exceeds a positive threshold value. Upon the instigation of the traction state, the electric motor 104 is commanded to amplify the torque output. Such amplification in the torque output propels the vehicle in a forward direction with an augmented power. The augmented power provision is particularly advantageous under such vehicular operational conditions when required power delivery is higher. Examples of such conditions may encompass situations where the vehicle is required to undergo rapid acceleration or when the vehicle is tasked with navigating upward on inclined terrains. The incorporation of the traction state thus ensures that the vehicle, through the enhanced torque output from the electric motor 104, handles and responds effectively to demanding operational scenarios, thereby optimizing performance and ensuring efficient power management.
[0042] In an exemplary aspect, if a rider is ascending a hill, the computed difference between the desired speed and actual speed might increase. Such difference, if greater than a set positive threshold, would transition the system 100 into the traction state, ensuring power delivery is prioritized.
[0043] In an embodiment, there exists a second state, namely a cruise state, which is selected by said VCU 108, when the computed difference is within a defined range demarcated by two predetermined threshold values. Specifically, when such computed difference is less than the positive threshold value and, in parallel, exceeds a negative threshold value, the electric motor 104 is made to transition into a state where a uniform speed and output are consistently maintained. The cruise state has been formulated with precision to be particularly suited for circumstances wherein the vehicle operates in the state that facilitates cruising at a constant velocity, abstaining from undergoing abrupt acceleration or substantial deceleration. This state ensures that during instances of steady vehicular movement.
[0044] In an exemplary aspect, on a flat road, when the rider sets the throttle to maintain a constant speed, the computed difference might be within the thresholds (positive threshold and negative threshold). The system 100 then maintains the cruise state, providing a steady and predictable response.
[0045] In an embodiment, a third driving state, namely regeneration state, is selected by said VCU 108 in instances where the computed difference is determined to fall beneath the negative threshold value. Within the regeneration state, the electric motor 104 undergoes a transformation, being effectively converted into a generator. As a result of such transformation, kinetic energy, prevalent during scenarios such as when the vehicle undergoes deceleration or engages in downhill motion, is actively harnessed. Such kinetic energy is then converted back into electrical energy, following the principles of energy conservation. Subsequently, the energy, once regenerated in the aforesaid manner, is reintroduced into the battery pack 102 of the vehicle. Such methodical reintroduction of regenerated energy aids in augmenting the overall efficiency of said power management system 100, thereby serving to protract the operational range of the vehicle. Through the implementation of the regeneration state, facilitated by such VCU 108, the capacity of the vehicle to recapture and reuse energy, particularly under conditions conducive to energy regeneration, is significantly enhanced, culminating in a more sustainable and efficient vehicle operation. In regeneration state, the regenerative braking unit can be designed to mimic the sensation a rider experiences during engine braking in an ICE based vehicle. For electric vehicles, engine braking doesn't occur naturally since electric motors work differently from internal combustion engines. In electric vehicles, the regeneration state mimics engine braking through regenerative braking, which is modulated based on rider inputs such as throttle position and speed.
[0046] In an embodiment, during the regeneration state, the VCU 108 adjusts the electric current to the windings of electric motor 104, thereby altering the electromagnetic fields of electric motor 104. Instead of drawing current to produce torque, the rotor of electric motor 104, driven by the inertia of the vehicle, induces a current in the stator windings (of electric motor 104). The phenomenon, based on Faraday's law of electromagnetic induction, allows the kinetic energy of the vehicle (when moving) to be captured as the vehicle generates an electromotive force (EMF) within the electric motor-turned-generator. The VCU 108 then modulates the amount of regenerated energy within safe limits for the acceptance rate of the battery pack 102. The resultant electrical energy flows back into the battery pack 102 preserving the health of battery pack 102 and augmenting the energy efficiency and operational range of the vehicle.
[0047] In one embodiment of the disclosure, during the specified traction state, said VCU 108 is configured to access and utilize a predetermined mapping that correlates throttle position with a power multiplier. The mapping, often represented in the form of a matrix or table, determines the relationship between the current position of the throttle and the corresponding power multiplier factor. Based on the relationship, said VCU 108 is further adapted to compute a demanded electric current that is subsequently expected to be delivered by the electric motor 104. The calculated electric current, as determined by said VCU 108, represents the requisite power output needed from such electric motor 104 to maintain or achieve the desired traction state of the vehicle. It is emphasized that the precision with which said VCU 108 calculates the demanded electric current is instrumental in ensuring optimal power delivery, efficient energy consumption, and overall enhanced performance of the power management system 100 of vehicle. Consequently, the integration of such a throttle position versus power multiplier map within said VCU 108 provides a systematic and reliable mechanism for real-time adjustments of electric power demands, aligning them with the dynamic requirements of the vehicle. An exemplary mapping of throttle position with a power multiplier factor is depicted in table.1.
Throttle Position (%) Power Multiplier Factor
0 0
10 5
20 20
30 40
40 60
50 80
60 95
70 100
80 100
90 100
100 100
Table. 1

[0048] The VCU 108 can be interfaced with a motor controller. Based on the computed demanded electric current, which the motor controller is expected to draw from the battery 102. Upon determination, the electric current requested by the motor controller is lesser than an electric current limit set by the motor controller, VCU 108 facilitates the actuation process to enable the motor controller to extract the calculated demanded electric current from the battery pack 102. Furthermore, an inherent safeguard mechanism can be embedded within VCU 108, ensuring that the motor controller does not exceed the stipulated electric current limit. Such orchestration by said VCU 108 serves as an essential control measure, striving to uphold the integrity of both the motor controller and the battery pack 102 by averting overcurrent situations. Moreover, the VCU 108 monitors and controls the rate at which the motor 104 accelerates. By managing the electric current's draw, the VCU 108 protects the motor 104 against electrical overloads, and prevents uncontrolled vehicle accelerations. The VCU 108 upholds the functional and safety standards of the electric vehicle's power system, providing a balanced approach to performance and protection.
[0049] In an embodiment, VCU 108 may effectively manage the electric current supply to the motor controller. Upon reception of a request from the motor controller for electric current, VCU 108 is programmed to determine the magnitude of the requested electric current. If the magnitude of the requested electric current exceeds the electric current limit imposed by the motor controller, VCU 108 enables the motor controller to draw an electric current up to the imposed current limit. Consequently, the possibility of overcurrent situations or damage to the motor or associated systems is significantly reduced. Such VCU 108 thereby acts as a protective intermediary, ensuring that the motor controller does not draw current beyond the imposed current limit, irrespective of the magnitude of the current initially requested. Through such mechanism, risks associated with excessive current draw are mitigated, thereby promoting the longevity of the electrical components of the vehicle and ensuring stable and efficient operation of the power management system 100.
[0050] In an embodiment, during the cruise state, an initial electric current value requisite for sustaining the desired speed is computed by said VCU 108. Such computation is established by a pre-configured table depicting the relationship between the requested velocity and the constant electric current. Within the aforesaid table, possible requested velocities are paired with the corresponding electric current values, which are deemed constant. As the vehicle enters the cruise state and a particular velocity is desired or set by the driver or an automated system, said VCU 108 retrieves the corresponding electric current value of said velocity from the table. The retrieved electric current value, is then employed by said VCU 108 as a reference, facilitating the delivery of the appropriate electric current to the propulsion system of vehicle to ensure that the set or desired velocity is consistently maintained throughout the cruise state. The establishment requested velocity versus constant electric current table provides a robust and precise mechanism through which the power management system 100 can reliably and efficiently modulate the electric current during the cruise state, thereby optimizing energy utilization and promoting vehicular operational consistency. Furthermore, through the employment of such VCU 108 in parallel with the aforementioned table, the power management system 100 establishes an alignment between the desired vehicular velocity and the requested electric current, ensuring an optimized, smooth, and energy-efficient cruising experience. An exemplary pre-configured table.2 depicting the relationship between the requested velocity and the constant electric current is mentioned below.

Requested Velocity Constant Electric Current
10 2
20 7
40 27
60 60
80 107
Table. 2

[0051] In an embodiment when the vehicle is in cruise state, VCU 108 adjusts the supplied operating electric current to preserve a required velocity. It is appreciated that by means of specific algorithms or control mechanisms embedded within such VCU 108, precise regulation of the electric current is facilitated, ensuring the ability of vehicle to sustain the desired velocity without significant fluctuations. Furthermore, through the aforementioned adjustment capabilities of said VCU 108, optimization of energy consumption within the vehicle is realized, thereby enhancing overall operational efficiency and extending the longevity of the battery pack 102 of vehicle. Continuous monitoring and real-time adjustment provide a reliable power management solution, ensuring a consistent and smooth cruising experience for the occupants of the vehicle. In an embodiment, a PID controller adjusts the current supplied to the motor to align the actual velocity with the requested velocity using tuned proportional, integral, and derivative gains.
[0052] In an embodiment, VCU 108 can be associated with a pre-stored data corresponding to each driving mode (e.g., rush mode, eco mode etc.). The pre-stored data comprising specific settings for each mode, which are crucial in determining how the vehicle responds to driver inputs and environmental conditions. For each driving mode, pre-stored data include the throttle to power multiplier, the regen torque table, the regen multiplier, threshold limits, and the PID gains for the cruise state. The throttle to power multiplier dictates how much power is delivered in response to the throttle input by the driver. For example, in rush mode, a higher power output is provided for the same throttle input compared to an eco-mode, resulting in quicker acceleration. By accessing the mode specific pre-stored data, the VCU 108 can dynamically adjust requested electric current based on driving mode. As VCU 108 accesses mode specific pre-stored data, requested electric current can vary based on different riding modes to give the user a distinctive feel (e.g., sharp increase in current supply in rush mode vs gradual increase in eco mode). By integrating the mode-specific differences in the multipliers with the varying electrical power provided in each mode, along with the mode-dependent limits set in the motor controller, VCU 108 can create customized acceleration responses across different speeds and different modes.
[0053] As the VCU 108 accesses mode-specific pre-stored data, the regenerative braking force can vary according to different riding modes, providing the user with a unique experience (e.g., more aggressive deceleration or engine-braking effect in eco mode versus milder in rush mode or vice-a-versa). Through the integration of mode-specific differences in these regenerative settings with the varying levels of regenerative force applied in each mode, and taking into account the mode-dependent deceleration limits set in the motor controller, the VCU 108 can create customized deceleration responses that vary across different speeds and modes. The customized regenerative braking enables optimization of optimal energy recovery during braking while catering to the driving preferences and safety requirements of the user.
[0054] In an embodiment, VCU 108, when in the regeneration state, selects a regeneration torque based on a detected current rotational speed of the vehicle. Such selection is derived from a vehicle velocity table correlating regen torque values with corresponding vehicle velocities. Specifically, upon detection of a particular rotational speed by said VCU 108, a corresponding regen torque value is identified from the vehicle velocity table. Such vehicle velocity table, containing a series of regen torque values plotted against respective vehicle velocities, acts as a reference guide to ensure that the appropriate regen torque is applied at varying speeds of the vehicle. The improvised approach adopted by VCU 108, ensures that the regeneration process is optimized for energy recovery and efficiency, catering to the dynamic needs of the vehicle during the operation. An exemplary vehicle velocity table is depicted in table. 3.
Vehicle Velocities (km/h) Regen Torque Values (Nm)
0 0
10 2.5
20 5
30 10
40 12.5
50 12.5
60 12.5
70 12.5
80 12.5

Table. 3
[0055] In yet another embodiment, VCU 108 is equipped with a mechanism for determining a regen current limit. Such determination is based upon the selection of a regen torque and a regen current multiplier. The regen current multiplier is not static but is subjected to adjustments. Specifically, adjustments to the regen current multiplier are made in accordance with the throttle input that is received. Consequently, the flexibility and precision of power management in the vehicle are enhanced, allowing for a more responsive and efficient energy conservation mechanism, particularly when considering regeneration processes during vehicle operation. The interplay between the selected regen torque and the adjustability of the regen current multiplier, based on the throttle input, modulates energy flow, ensuring optimal performance and safety parameters are consistently met.
[0056] In an embodiment, when said VCU 108 determines that the calculated regen current limit exceeds a predetermined maximum current corresponding to a set maximum torque established by the motor controller, the motor controller limits the maximum current and ensures that the maximum limited current is regenerated.. Such limitation safeguards the motor controller and connects systems from overloads or damage due to excess current flow. The underlying mechanism implemented by said VCU 108 provides an added layer of protection, optimizing the operational safety and longevity of the power management system 100. This way, the motor controller operates within safe parameters, thereby enhancing overall system performance and reliability.
[0057] In another embodiment, if the regen current limit, as determined by said VCU 108, is lesser than the maximum current corresponding to the maximum torque as predefined by the motor controller, then the regen current is duly supplied to the electric motor 104. The comparison of the regen current limit with the maximum current ensures an efficient utilization and optimization of the power delivered to the electric motor 104. Such mechanism ensures that the energy regenerated during processes like braking or deceleration is effectively harnessed and supplied to the electric motor 104, thereby optimizing the energy consumption of the vehicle and extending the operational efficiency. The configuration ensures a balance between energy conservation and effective performance of the electric motor 104, providing a predictable riding experience through controlled engine braking effect. This harmony allows the vehicle to operate within the safe and efficient parameters set by the motor controller, enhancing both the sustainability and the driving dynamics of the vehicle.
[0058] In an embodiment, the VCU 108 ascertains a necessity for a shift in the driving state. Such transition is discerned between the first driving state and the subsequent second driving state. Such determination by said VCU 108 is predicated upon a velocity requirement that has been calculated priorly. Specifically, when the calculated required velocity exhibits certain predefined thresholds or parameters, such VCU 108 engages the analytical mechanisms to recognize whether the transition between the first and the second driving states is imperative for optimal vehicular performance. The process ensures that the power management system 100 remains responsive and adaptive to the dynamic driving conditions, thereby enhancing the efficiency and efficacy of the operational parameters of vehicle. Through such an arrangement, the power management system 100, with the assistance of said VCU 108, fosters improved adaptability and precision in adjusting the driving states in correlation with the calculated required velocity.
[0059] The particular modification in the driving state is correlated with either the decrease (ramping down) or the increase (ramping up) of the operating electric current that is provided to the electric motor 104 until a specified threshold velocity is reached. Such ramping down or the ramping up of the operating electric current is set into motion, if the determined rotational speed surpasses the threshold value. Within the aforesaid context, VCU 108 is configured to monitor and manage the variations in the driving state, ensuring that the electric motor 104 receives an appropriate amount of electric current based on the driving conditions and operational requirements. Through such mechanism, optimized energy efficiency and performance of the electric motor 104 in the vehicle can be achieved, while also ensuring that the vehicle operates within safe and predetermined parameters as established by said VCU 108. Thus, the vehicle operates in a smooth manner, removing any unwanted transitions happening.
[0060] In an embodiment, VCU 108 manages the transitioning of the driving state of the vehicle. Specifically, when transitioning from the traction state to the cruise state, VCU 108 is configured to supervise a linear ramping down of the operating electric current from a higher current value used for acceleration in traction state to a lower value used for cruising in cruise state. Such decrement in the electric current is maintained progressively and continuously until such time as the cruise state is achieved. By employing such a linear reduction in the electric current, VCU 108 ensures a smooth and predictable transition between the two states, mitigating abrupt changes in power output, thereby enhancing both the efficiency of the power management system 100 and the overall driving experience. Such provision by said VCU 108 illustrates an efficient approach to vehicular power modulation, emphasizing the importance of controlled and graded transitions in the driving states, critical for both vehicle performance and user comfort.
[0061] In said power management system 100 for the vehicle, the transition of the driving state of the vehicle from the regeneration state to the cruise state can be obtained. VCU 108 effectuates a linear ramping-up of the operating electric current. Such linear incrementation of the electric current is sustained until such time that the cruise state of the vehicle is achieved from a regeneration current to a positive traction current used for cruising. Throughout the transition phase, said VCU 108 ensures a seamless and continuous progression in the modulation of the electric current, thereby providing an optimized transition process devoid of abrupt fluctuations. Such linear escalation of the operating electric current orchestrated by the VCU 108 offers enhanced vehicular performance, smoother transitions between states, and augments the overall efficiency of the power management system 100 in the vehicle.
[0062] In an embodiment, the VCU 108 possesses a mechanism to determine the optimal moment to transition between driving states, based on the computational difference between the calculated required velocity and the determined rotational speed. The mechanism is predicated on monitoring whether the differential deviates from established positive or negative thresholds, and for how long the deviation persists. Rather than abrupt or frequent shifts in driving states, which can lead to suboptimal power consumption, the VCU 108 waits for the difference to breach the thresholds before instigating the state change. This ensures that transient or minor fluctuations do not trigger state changes, averting inefficiencies. Such premature transitions, aside from creating an inconsistent driving experience, could lead to excessive energy expenditure. In essence, by conditioning state changes on both the magnitude and duration of deviations, VCU 108 fosters a balance between responsiveness and energy conservation, thus maximizing the overall efficiency of system and ensuring a harmonious driving experience.
[0063] FIG. 2 illustrates a method 200 for managing power management of a vehicle, in accordance with embodiments of the present disclosure. The step 202 encompasses determining the rotational speed associated with the electric motor. The rotational speed directly correlates with the supplied operating electric current and a throttle input. The interplay between the throttle input and the operating electric current provides insights into the behavior and functioning of the electric motor. The step 204 is the calculation of a required velocity, which is achieved by considering the received throttle input. The throttle input acts as a primary determinant, guiding the computation process to establish the desired velocity necessary for the vehicle to match the intentions of driver. At step 206, the method 200 progresses to compute the difference between the calculated required velocity and the previously determined rotational speed. The aforesaid step pinpoints the disparity, if any, between the current operational state of the vehicle and the desired state as inferred from the throttle input. At step 208 the method 200 then calculates the requested electric current that is achieved by basing the calculation on the received throttle input, which aids in determining the magnitude of electric current necessary to drive the motor in alignment with the intentions of driver. At step 210, the culmination of the method 200 lies in selecting an appropriate driving state (e.g., traction state, cruise state and regeneration state). The decision lies on the computed difference from the earlier step. The driving state, in essence, governs the operation of the motor. The traction state can be activated when the computed difference surpasses a predefined positive threshold. In scenarios demanding rapid acceleration or overcoming resistance, such as uphill driving, this traction state enables generation of maximum power. By optimizing torque delivery to the vehicle's drivetrain, traction state addresses instances requiring increased power, ensuring robust vehicle performance during challenging maneuvers. The cruise state can be triggered when the computed difference lies between a set positive and negative threshold, the cruise state is designed for maintaining consistent speeds, particularly during straight-road or highway driving. The cruise state provides balanced power and efficiency, and also enable the vehicle to sustain desired speed without unnecessary energy consumption, ideal for prolonged and steady drives. The regeneration state can be triggered when the computed difference descends below a specific negative threshold. The regeneration state facilitates energy recovery during a deceleration or braking event. By converting potentially wasted energy back into usable power, the regeneration state enhances battery longevity and overall vehicle efficiency along with ensuring a predictable deceleration of the vehicle.
[0064] FIG. 3 illustrates a vehicle-rider interaction diagram, in accordance with embodiments of the present disclosure. The throttle input (provided by rider) is processed to ascertain a throttle percentage which serves as an input to the motor controller. The motor controller utilizes the throttle percentage to determine a torque demand. Simultaneously, the motor speed influences the torque demand that is further processed to generate a current demand, which is subjected to a current limiter. The current limiter ensures that the current supplied to the electric motor 104 stays within preset limits. As a result, the available motor torque is produced by the electric motor 104, which is an output that is fed into the VCU 108 that employs a throttle response algorithm to process the available motor torque and optimally control the operation of the vehicle. Together, the components and interconnections of FIG. 3 manifest an apparatus to manage power in the vehicle, ensuring efficient and responsive operations in accordance with rider inputs and prevailing conditions.
[0065] FIG. 4 illustrates a throttle response diagram, in accordance with embodiments of the present disclosure. The throttle response is utilized by the VCU 108, which controls the vehicle state and corresponding state based current limits, which influence the operations of the motor. Real-time parameters including throttle percentage, motor speed, and current vehicle velocity can be continuously monitored. The aforesaid parameters, in turn, provide input to throttle response current calculator and throttle response state selector. The throttle response current calculator processes the received inputs and interfaces with the throttle response state selector, which selects an appropriate driving state. The throttle response state selector can choose among the traction state, cruise state, regeneration state and transition states in between aforesaid states. The throttle response current and motor state orchestrate the optimal performance and energy management of the vehicle under diverse operational conditions.
[0066] The foregoing description of the specific embodiments will so fully reveal the general nature of the embodiments herein that others can, by applying current knowledge, readily modify and/or adapt for various applications such specific embodiments without departing from the generic concept, and, therefore, such adaptations and modifications should and are intended to be comprehended within the meaning and range of equivalents of the disclosed embodiments. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. Therefore, while the embodiments herein have been described in terms of preferred embodiments, those skilled in the art will recognize that the embodiments herein can be practiced with modification within the spirit and scope of the embodiments as described herein.
[0067] It should be apparent to those skilled in the art that many more modifications besides those already described are possible without departing from the inventive concepts herein. The inventive subject matter, therefore, is not to be restricted except in the spirit of the appended claims. Moreover, in interpreting both the specification and the claims, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms “comprises” and “comprising” should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refer to at least one of something selected from the group consisting of A, B, C … and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.

CLAIMS
What is claimed is:
1. A power management system for a vehicle, the system comprising:
a battery pack to supply an operating electric current to an electric motor;
a sensing unit determines:
a rotational speed associated with the electric motor, wherein the rotational speed corresponds to the supplied operating electric current; and
a throttle input; and
a vehicle control unit (VCU):
receives the throttle input and the rotational speed;
calculates a required velocity based on the received throttle input;
computes the difference between the calculated required velocity and the determined rotational speed;
calculate a requested electric current based on the received throttle input;
select a driving state based on the computed difference, wherein the driving state controls an operation of the motor, and wherein the driving state is selected from:
a traction state if the computed difference is positive and greater than a positive threshold value;
a cruise state if the computed difference is lesser than the positive threshold value and greater than a negative threshold value; and
a regeneration state if the computed difference is lesser than the negative threshold value.
2. The system as claimed in claim 1, wherein in the traction state, the VCU utilizes a throttle position vs power multiplier map to calculate a demanded electric current from the electric motor.
3. The system as claimed in claim 2, wherein the VCU allows a motor controller to draw the calculated demanded electric current from the battery, if the requested electric current is lesser than an electric current limit imposed by the motor controller.
4. The system as claimed in claim 2, wherein the VCU allows the motor controller to draw a limited electric current, if the requested electric current is higher than the electric current limit imposed by the motor controller.
5. The system as claimed in claim 1, wherein in the cruise state, the VCU calculates an initial electric current value required to maintain the requested velocity based on a requested velocity vs constant electric current table.
6. The system as claimed in claim 1, wherein in the cruise state, the VCU adjusts the supplied operating electric current to maintain the required velocity.
7. The system as claimed in claim 1, wherein the VCU in the regeneration state selects, based on the current rotational speed, a regen torque from a regen torque vs vehicle velocity table.
8. The system as claimed in claim 7, wherein the VCU calculates a regen current limit based on the selected regen torque, wherein if the calculated regen current limit is higher than a maximum current corresponding to a maximum torque set by the regen torque vs electric motor rpm table on the motor controller, then the maximum current is limited by the motor controller.
9. The system as claimed in claim 7, wherein if the calculated regen current limit is lower than the maximum current corresponding to the maximum torque set by the regen torque vs electric motor rpm table on the motor controller, then the regen current is supplied to the motor.
10. The system as claimed in claim 7, wherein the regen current limit is associated with a regen current multiplier, wherein the regen current multiplier is adjusted based on the throttle input.
11. The system as claimed in claim 1, wherein the VCU determines a requirement of a transition in the driving state from a first driving state and the second driving state, based on the calculated required velocity.
12. The system as claimed in claim 1, wherein the change in driving state is associated with ramping down or ramping up the operating electric current supplied to the electric motor till the required velocity is achieved, wherein the ramping down or the ramping up the operating electric current initiates if the determined rotational speed exceeds a pre-set threshold value.
13. The system as claimed in claim 1, wherein transitioning the driving state of the vehicle from the traction state to the cruise state comprises linearly ramping down the operating electric current till the cruise state is achieved.
14. The system as claimed in claimed 1, wherein transitioning the driving state of the vehicle from the regeneration state to the cruise state comprises linearly ramping up the operating electric current till the cruise state is achieved.
15. The system as claimed in claimed 1, wherein the requested electric current is dependent on a driving mode of the vehicle.
16. A method for managing power management of a vehicle, the method comprising:
determining, a rotational speed associated with the electric motor, wherein the rotational speed corresponds to the supplied operating electric current and a throttle input; and
calculating, a required velocity based on the received throttle input;
computing, the difference between the calculated required velocity and the determined rotational speed;
calculate a requested electric current based on the received throttle input;
selecting, a driving state based on the computed difference, wherein the driving state controls an operation of the motor, and wherein the driving state is selected from:
a traction state if the computed difference is positive and greater than a positive threshold value;
a cruise state if the computed difference is lesser than the positive threshold value and greater than a negative threshold value; and
a regeneration state if the computed difference is lesser than the negative threshold value.

ABSTRACT
The present disclosure introduces a power management system. This system includes a battery pack, sensing unit, and vehicle control unit (VCU). The battery pack supplies an operating electric current to an electric motor. The sensing unit measures the rotational speed of the electric motor, which ties to both the current and a throttle input. The VCU then takes in this throttle input and rotational speed. From the throttle input, the VCU determines a needed velocity, figures out the difference between this velocity and the actual rotational speed, and then discerns a necessary electric current. Based on the difference, the VCU chooses a driving state to steer the motor. It opts for a traction state when the difference goes beyond a set positive mark, a cruise state when it's between certain values, and a regeneration state when it drops beneath a specified negative threshold.Further, VCU can control transition states in between the aforesaid states.
Fig. 1 , Claims:CLAIMS
What is claimed is:
1. A power management system for a vehicle, the system comprising:
a battery pack to supply an operating electric current to an electric motor;
a sensing unit determines:
a rotational speed associated with the electric motor, wherein the rotational speed corresponds to the supplied operating electric current; and
a throttle input; and
a vehicle control unit (VCU):
receives the throttle input and the rotational speed;
calculates a required velocity based on the received throttle input;
computes the difference between the calculated required velocity and the determined rotational speed;
calculate a requested electric current based on the received throttle input;
select a driving state based on the computed difference, wherein the driving state controls an operation of the motor, and wherein the driving state is selected from:
a traction state if the computed difference is positive and greater than a positive threshold value;
a cruise state if the computed difference is lesser than the positive threshold value and greater than a negative threshold value; and
a regeneration state if the computed difference is lesser than the negative threshold value.
2. The system as claimed in claim 1, wherein in the traction state, the VCU utilizes a throttle position vs power multiplier map to calculate a demanded electric current from the electric motor.
3. The system as claimed in claim 2, wherein the VCU allows a motor controller to draw the calculated demanded electric current from the battery, if the requested electric current is lesser than an electric current limit imposed by the motor controller.
4. The system as claimed in claim 2, wherein the VCU allows the motor controller to draw a limited electric current, if the requested electric current is higher than the electric current limit imposed by the motor controller.
5. The system as claimed in claim 1, wherein in the cruise state, the VCU calculates an initial electric current value required to maintain the requested velocity based on a requested velocity vs constant electric current table.
6. The system as claimed in claim 1, wherein in the cruise state, the VCU adjusts the supplied operating electric current to maintain the required velocity.
7. The system as claimed in claim 1, wherein the VCU in the regeneration state selects, based on the current rotational speed, a regen torque from a regen torque vs vehicle velocity table.
8. The system as claimed in claim 7, wherein the VCU calculates a regen current limit based on the selected regen torque, wherein if the calculated regen current limit is higher than a maximum current corresponding to a maximum torque set by the regen torque vs electric motor rpm table on the motor controller, then the maximum current is limited by the motor controller.
9. The system as claimed in claim 7, wherein if the calculated regen current limit is lower than the maximum current corresponding to the maximum torque set by the regen torque vs electric motor rpm table on the motor controller, then the regen current is supplied to the motor.
10. The system as claimed in claim 7, wherein the regen current limit is associated with a regen current multiplier, wherein the regen current multiplier is adjusted based on the throttle input.
11. The system as claimed in claim 1, wherein the VCU determines a requirement of a transition in the driving state from a first driving state and the second driving state, based on the calculated required velocity.
12. The system as claimed in claim 1, wherein the change in driving state is associated with ramping down or ramping up the operating electric current supplied to the electric motor till the required velocity is achieved, wherein the ramping down or the ramping up the operating electric current initiates if the determined rotational speed exceeds a pre-set threshold value.
13. The system as claimed in claim 1, wherein transitioning the driving state of the vehicle from the traction state to the cruise state comprises linearly ramping down the operating electric current till the cruise state is achieved.
14. The system as claimed in claimed 1, wherein transitioning the driving state of the vehicle from the regeneration state to the cruise state comprises linearly ramping up the operating electric current till the cruise state is achieved.
15. The system as claimed in claimed 1, wherein the requested electric current is dependent on a driving mode of the vehicle.
16. A method for managing power management of a vehicle, the method comprising:
determining, a rotational speed associated with the electric motor, wherein the rotational speed corresponds to the supplied operating electric current and a throttle input; and
calculating, a required velocity based on the received throttle input;
computing, the difference between the calculated required velocity and the determined rotational speed;
calculate a requested electric current based on the received throttle input;
selecting, a driving state based on the computed difference, wherein the driving state controls an operation of the motor, and wherein the driving state is selected from:
a traction state if the computed difference is positive and greater than a positive threshold value;
a cruise state if the computed difference is lesser than the positive threshold value and greater than a negative threshold value; and
a regeneration state if the computed difference is lesser than the negative threshold value.