Description:Field of Invention
[001] The invention relates to vehicles that are propelled by an electric motor. It more particularly relates to electric vehicles that have been provided with a system to convert energy from braking back into electrical energy for charging their batteries. It specifically relates to the system's method of operation for converting energy recovered from braking back into electrical energy to charge their batteries.
Background of the Invention
[002] In electric commercial vehicles, existing regenerative braking systems are unable to carry out dynamic adjustments to the regenerative torque. The absence of real-time control on regenerative braking torque based on available retarder torque and braking demand means that the braking performance remains more or less fixed. Given the fixed nature of regenerative braking, the efficiency of converting the braking energy back to electrical energy for charging the battery, therefore, remains extremely limited.
[003] The absence of real-time information sharing between the vehicle control unit and the electronic braking system via a vehicle-wide communication network removes the possibility of coordination between these vehicle-mounted systems to improve the system's braking and energy recuperation effectiveness. The electronic braking systems provided in electric commercial vehicles with such braking systems are, therefore, unable to dynamically request the use of unused regenerative torque to optimise energy recuperation.
[004] Given these shortcomings, it is understandable why the existing braking systems utilising regenerative braking components are considered less adaptable. Typical user complaints of the absence of smooth braking while transitioning from regenerative braking to braking using conventional mechanical brakes means that this technology has a long way to go before users start opting for it for obtaining an increase in vehicular range while also ensuring braking comfort and effectiveness. Therefore, the present invention's objective is to improve the utilisation of existing systems to allow better regenerative braking performance.
[005] It is another objective of the present invention to increase the energy recovered during the regenerative braking of the vehicle.
[006] It is still another objective of the present invention to improve the overall effectiveness of braking systems where at least a part of the braking is performed by a regenerative braking system.
[007] It is yet another objective of the present invention to improve the effectiveness and comfort of vehicles using regenerative braking to meet at least a part of their braking requirement.
[008] It is still another objective of the present invention to improve the adaptiveness of the braking system obtaining at least a part of their braking requirement using the regenerative braking system.
Summary of the Invention
[009] An embodiment of the invention achieving the stated objective that is a method for enhancing the energy recuperated from regenerative braking, as implemented through a system comprising of, a traction motor, a high voltage battery, a battery management system (BMS), a motor control unit (MCU), a vehicle control unit (VCU), an electronic braking system (EBS), an EBS Sensor Interface, a vehicle Control Area Network (CAN) interface, a brake pedal sensor, and wheel speed sensors, and actuators for pneumatic brake actuator valves. In accordance with the manner of execution of the method for enhancing the energy recuperated from regenerative braking, when the vehicle starts operating the, as a first step, the vehicle control unit (VCU), starts monitoring and accepting inputs on values of battery parameters State of Charge, Current Limit, and Battery Health from the battery management system (BMS) that is linked to the high voltage battery, starts monitoring and accepting inputs on retardation torque value from the motor control unit (MCU) that is linked with the traction motor, starts monitoring and accepting inputs on regenerative torque value from the Electronic Baking System (EBS) that is linked to the wheel speed, and pedal sensors and actuators for pneumatic brake valves of the vehicle through the EBS interface, and starts monitoring and accepting inputs from Electronic Braking System (EBS) on and about actuation of the braking pedal by the vehicle’s user; as a second step, executed upon pressing of the brake pedal by the vehicle user, the Electronic Baking System (EBS) assesses the inputs from vehicle mounted sensors on pedal position, wheel speeds, steering angle and vehicle centre of gravity and communicates the extent of actuation of braking pedal and suggests the maximum achievable regenerative braking in the instant to the VCU; as a third step, executed after EBS has communicated to the VCU the extent of brake pedal actuation with the maximum achievable regenerative braking in the instant, the VCU then considers the input and calculates based upon inputs on vehicle speed and braking input an optimized regenerative torque value, and then communicates the optimized regenerative torque value for the traction motor to the MCU so as to maximize battery regeneration; as a fourth step, executed after the VCU has communicated the optimized regenerative torque value to the MCU for execution through the torque motor, the MCU in turn communicates the actual regeneration torque produced by the traction motor to the VCU that in turn communicates it to the Electronic Braking System (EBS); as a fifth step, after regenerative braking has been initiated at the traction motor by the MCU based on instructions received through the VCU and EBS, the EBS upon receiving the input on actual regenerative braking torque achieved from the MCU and through the VCU, reassesses the additional regenerative torque that can be obtained, based upon the inputs available from the vehicle sensors, in addition to the already obtained regenerative torque, and causes and additional regenerative torque demand to be incorporated through an override command transmitted to the VCU and through it to the MCU for execution through the traction motor; and as a sixth step, after the additional regenerative torque has been incorporated by the VCU through an override command from the EBS, the EBS causes the actuation of the actuators linked to the pneumatic brake valves to fulfil the remaining unfulfilled braking demand as assessed from the data available on the position of the brake pedal and wheel speed as known from the brake pedal and wheel speed sensors.
Brief Description of Drawings
[0010] The present invention is illustrated in the accompanying drawings that contain references numerals for indicating its various parts. The description of the present invention would, therefore, be better understood with reference to accompanying diagrams, wherein
[0011] Figure 1 discloses the block diagram of the system on which the present invention has been implemented.
[0012] Figure 2 discloses information flow diagram for the system being run in accordance with the present invention.
[0013] Figure 3 discloses a flow chart representing the method in accordance with the present invention.
Detailed Description of the Invention
[0014] Referring to the set of figures 1, 2, and 3, method for enhancing the energy recuperated from regenerative braking in accordance with the present invention is implemented by a system comprises of, a traction motor, a high voltage battery, a battery management system (BMS), a motor control unit (MCU), a vehicle control unit (VCU), an electronic braking system (EBS), an EBS Sensor Interface, a vehicle Control Area Network (CAN) and its interface, a brake pedal sensor, wheel speed sensors and actuators for pneumatic braking valves. The present invention is as shown in the figures and as described hereinafter.
[0015] In the system for implementing the present method, referring to Fig. 1, it is stated that, the BMS is linked with the VCU through the CAN interface. The MCU is linked to the VCU through the CAN interface. The traction motor is linked to the MCU though a high voltage interface. The traction motor is linked to the driving wheels of the vehicle through a mechanical linkage. The EBS is linked with the VCU through the CAN interface. The EBS is linked to an EBS sensor interface through an electrical connection. The EBS sensor interface is linked to the pedal position sensor and the wheel speed sensor through electrical connection provided for the same; and the EBS is linked to an electrical actuator for pneumatic brake actuating valves through a link from the EBS sensor interface. The traction motor transmits the recuperated energy in regenerative braking a high voltage battery linked to the BMS via an electrical connection provided for the same.
[0016] The communications for the execution of the steps, between the BMS, MCU, VCU and EBS happens through the vehicle Control Area Network (CAN) interface. Given the use of CAN interface for facilitating communication between the critical components of the system, the mentioned systems can also access information from other vehicle mounted sensors as the vehicle designers may find appropriate to provide on the vehicle, for example, steering angle, and vehicle centre of gravity, besides the shown wheel speed and pedal position sensors.
[0017] Referring to the set of figures 2 and 3, about the method for enhancing the energy recuperated from regenerative braking it is stated that, when the vehicle starts operating the, as a first step, the vehicle control unit (VCU), starts monitoring and accepting inputs on values of battery parameters State of Charge, Current Limit, and Battery Health from the battery management system (BMS) that is linked to the high voltage battery, starts monitoring and accepting inputs on available retardation torque value from the motor control unit (MCU) that is linked with the traction motor, starts monitoring and accepting inputs on regenerative torque value from the Electronic Baking System (EBS) that is linked to the wheel speed, and pedal sensors and actuators for pneumatic brake valves of the vehicle through the EBS interface, and starts monitoring and accepting inputs from Electronic Braking System (EBS) on and about actuation of the braking pedal by the vehicle’s user from the brake pedal sensor provided for the same.
[0018] Referring to the set of figures 2 and 3, about the method for enhancing the energy recuperated from regenerative braking it is stated that, as a second step, executed upon pressing of the brake pedal by the vehicle user, the Electronic Baking System (EBS) assesses the inputs from vehicle mounted sensors on pedal position, wheel speeds, steering angle and vehicle centre of gravity and communicates the extent of actuation of braking pedal and suggests the maximum achievable regenerative braking in the instant to the VCU.
[0019] Referring to the set of figures 2 and 3, about the method for enhancing the energy recuperated from regenerative braking it is stated that, as a third step, executed after EBS has communicated to the VCU the extent of brake pedal actuation with the maximum achievable regenerative braking in the instant, the VCU then considers the input and calculates based upon inputs on vehicle speed and braking input an optimized regenerative torque value, and then communicates the optimized regenerative torque value for the traction motor to the MCU so as to maximize battery regeneration.
[0020] Referring to the set of figures 2 and 3, about the method for enhancing the energy recuperated from regenerative braking it is stated that, as a fourth step, executed after the VCU has communicated the optimized regenerative torque value to the MCU for execution through the traction motor, the MCU in turn communicates the actual regeneration torque produced by the traction motor to the VCU that in turn communicates it to the Electronic Braking System (EBS).
[0021] Referring to the set of figures 2 and 3, about the method for enhancing the energy recuperated from regenerative braking it is stated that, as a fifth step, after regenerative braking has been initiated at the traction motor by the MCU based on instructions received through the VCU and EBS, the EBS upon receiving the input on actual regenerative braking torque achieved from the MCU and through the VCU, reassesses the additional regenerative torque that can be obtained, based upon the inputs available from the vehicle sensors, in addition to the already obtained regenerative torque, and causes and additional regenerative torque demand to be incorporated through an override command transmitted to the VCU and through it to the MCU for execution through the traction motor.
[0022] For example, if VCU is causing a retardation torque of 1000 Nm to be applied, and the EBS suggests that out of the remaining available braking capacity of 1000 Nm retardation torque, an additional 500 Nm retardation torque must be applied. The EBS would send this value as an override command which indicates this much more torque can be utilized at the moment for regenerative braking. The VCU would incorporate this suggestion into its command value and cause this increase in retardation torque command to the taction motor (through the MCU).
[0023] Referring to the set of figures 2 and 3, about the method for enhancing the energy recuperated from regenerative braking it is stated that, as a sixth step, after the additional regenerative torque has been incorporated by the VCU through an override command from the EBS, the EBS causes the actuation of the actuators linked to the pneumatic brake actuating valves to fulfil the remaining unfulfilled braking demand as assessed from the data available on the position of the brake pedal and wheel speed as known from the brake pedal and wheel speed sensors. The steps 2 to 6 are continuously executed in a loop after the vehicle has been started, and the brake pedal has been pressed by the vehicle user to slow or stop the vehicle. The method so disclosed, provides smooth and efficient braking and co-ordination between different braking means to improve the vehicle user experience significantly.
[0024] Technical advantages offered by the invention i.e., method for enhancing the energy recuperated from regenerative braking are-
- It improves the utilisation of existing systems to allow better regenerative braking performance.
- It increases the energy recovered during the regenerative braking of the vehicle.
- It improves the overall effectiveness of braking systems where at least a part of the braking is performed by a regenerative braking system.
- It improves the comfort of vehicles using regenerative braking to meet at least a part of their braking requirement.
- It improves the adaptiveness of the braking system obtaining at least a part of their braking requirement using the regenerative braking system.
[0025] The disclosed invention, i.e. the method for enhancing the energy recuperated from regenerative braking, achieves all the set-out objectives.
[0026] 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 present invention has been herein described in terms of its preferred embodiment, those skilled in the art will recognize that the preferred embodiment herein disclosed, can be practiced with modifications within the scope of the invention herein described. , Claims:We Claim,
1. A method for enhancing the energy recuperated from regenerative braking in accordance with the present invention is implemented by a system comprises of,
• a traction motor,
• a high voltage battery,
• a battery management system (BMS),
• a motor control unit (MCU),
• a vehicle control unit (VCU),
• an electronic braking system (EBS),
• an EBS Sensor Interface,
• a vehicle Control Area Network (CAN) interface,
• a brake pedal sensor,
• wheel speed sensors, and
• actuators for pneumatic brake actuator valves,
wherein,
- when the vehicle starts operating the, as a first step, the vehicle control unit (VCU), starts monitoring and accepting inputs on values of battery parameters State of Charge, Current Limit, and Battery Health from the battery management system (BMS) that is linked to the high voltage battery, starts monitoring and accepting inputs on available retardation torque value from the motor control unit (MCU) that is linked with the traction motor, starts monitoring and accepting inputs on regenerative torque value from the Electronic Baking System (EBS) that is linked to the wheel speed, and pedal sensors and actuators for pneumatic brake valves of the vehicle through the EBS interface, and starts monitoring and accepting inputs from Electronic Braking System (EBS) on and about actuation of the braking pedal by the vehicle’s user;
- as a second step, executed upon pressing of the brake pedal by the vehicle user, the Electronic Baking System (EBS) assesses the inputs from vehicle mounted sensors on pedal position, wheel speeds, steering angle and vehicle centre of gravity and communicates the extent of actuation of braking pedal and suggests the maximum achievable regenerative braking in the instant to the VCU;
- as a third step, executed after EBS has communicated to the VCU the extent of brake pedal actuation with the maximum achievable regenerative braking in the instant, the VCU then considers the input and calculates based upon inputs on vehicle speed and braking input an optimized regenerative torque value, and then communicates the optimized regenerative torque value for the traction motor to the MCU so as to maximize battery regeneration;
- as a fourth step, executed after the VCU has communicated the optimized regenerative torque value to the MCU for execution through the traction motor, the MCU in turn communicates the actual regeneration torque produced by the traction motor to the VCU that in turn communicates it to the Electronic Braking System (EBS);
- as a fifth step, after regenerative braking has been initiated at the traction motor by the MCU based on instructions received through the VCU and EBS, the EBS upon receiving the input on actual regenerative braking torque achieved from the MCU and through the VCU, reassesses the additional regenerative torque that can be obtained, based upon the inputs available from the vehicle sensors, in addition to the already obtained regenerative torque, and causes and additional regenerative torque demand to be incorporated through an override command transmitted to the VCU and through it to the MCU for execution through the traction motor; and
- as a sixth step, after the additional regenerative torque has been incorporated by the VCU through an override command from the EBS, the EBS causes the actuation of the actuators linked to the pneumatic brake actuating valves to fulfil the remaining unfulfilled braking demand as assessed from the data available on the position of the brake pedal and wheel speed as known from the brake pedal and wheel speed sensors.
2. The method for enhancing the energy recuperated from regenerative braking as claimed in claim 1, wherein, steps 2 to 6 are continuously executed in a loop after the vehicle has been started, and the brake pedal has been pressed by the vehicle user to slow or stop the vehicle.
3. The method for enhancing the energy recuperated from regenerative braking as claimed in claim 1, wherein communication for the execution of the steps, between the BMS, MCU VCU and EBS happens through the vehicle Control Area Network (CAN) interface.
4. The method for enhancing the energy recuperated from regenerative braking as claimed in claim 1, wherein, the traction motor transmits the recuperated energy in regenerative braking a high voltage battery linked to the BMS via an electrical connection provided for the same.
5. The method for enhancing the energy recuperated from regenerative braking as claimed in the preceding claims, wherein, in the system for implementing the method,
- the BMS is linked with the VCU through the CAN interface;
- the MCU is linked to the VCU through the CAN interface;
- the traction motor is linked to the MCU though a high voltage interface;
- the traction motor is linked to the driving wheels of the vehicle through a mechanical linkage;
- the EBS is linked with the VCU through the CAN interface;
- the EBS is linked to an EBS sensor interface through an electrical connection;
- the EBS sensor interface is linked to the pedal position sensor and the wheel speed sensor through electrical connection provided for the same; and
- the EBS is linked to an electrical actuator for pneumatic brake actuating valves through a link from the EBS sensor interface.

Dated 27th day of February 2025

VIDIT CHOUBEY
(IN P/A 5566)
AGENT FOR THE APPLICANT(S)

To,
The Controller of Patents,
The Patent Office, at Mumbai