Description:FIELD OF INVENTION
[001] The present invention relates to an Energy Management System in an electric vehicle. Particularly, the present invention provides a system and method for efficiently modulating power deployment of a battery pack to an electric vehicle prime mover, specifically an electric motor.
BACKGROUND OF THE INVENTION
[002] Electric vehicles are gaining popularity as a replacement for conventional vehicles due to their efficient and diverse capabilities. Electric vehicles are one of the most promising alternatives to internal combustion engine vehicles in today's modern world. Electric vehicles are becoming more popular as a result of their near-zero carbon footprint and reduced reliance on expensive non-renewable energy sources. Electric vehicles are being formed in response to a need for a more cost-effective and environmentally friendly solution.

[003] To keep up with the modern era, an electric vehicle must meet and exceed consumer expectations in terms of performance, range, reliability, lifetime, and cost. These expectations, in turn, place a higher value on the design and configuration of the rechargeable batteries in electric vehicles, as batteries are currently one of the most expensive components associated with an electric vehicle, as well as one of the most significant limitations to vehicle range autonomy. Moreover, limited battery life has a direct impact on the vehicle's long-term reliability, which is aggravated by high battery replacement costs.

[004] The performance of an electric vehicle is indirectly governed by the battery pack which supplies the power to the prime mover – the electric motor. This is in turn dependent on the battery management system which manages the performance of the individual cells that together constitute a battery pack. In our invention, battery management systems work alongside the electric vehicle’s drive components to ascertain road and environmental conditions, and optimally modulate the power drawn from the battery. This increases immediate drive range, improves the driveability, and has a positive impact on the overall life of the battery.

[005] US Patent US7684942B2 teaches a battery management system and method thereof including a sensing unit, a micro control unit (MCU), a safety switch, cooling fan, an inverter, and a motor generator. The sensing unit measures the temperature and current of the battery, while the MCU estimates the state of charge and state of health based on the temperature and current. Further, a cooling fan is installed to provide cooling to the motor and other components. However, if a cooling fan fails or breaks down, it could lead to overheating in the system causing damage to the battery or even the electric vehicle itself. Moreover, the cited prior art document comprises of various components for the energy management system which is not an economic solution.

[006] Hence, with respect to the problems encountered above there is a need for a technology that monitors and manages the deployment of the battery to the Electric Vehicle motor. The present invention, therefore, aims to provide an economic battery management system that closely works in coordination with the electric vehicle controller. It provides ways to effectively deploy the available battery energy to electric motor considering the safety of both battery and motor.

OBJECTIVES OF THE INVENTION
[007] The primary objective of present invention is to provide an energy management system that deploy the existing battery energy to electric motor in an efficient manner.

[008] Another objective of the present invention is to provide a system to modulate the battery power depending on the driver’s requirement.

[009] Yet another objective of the present invention is to provide a system having a battery management system that controls and monitors the functioning of the battery, which increases the longevity of the battery.

[0010] Another objective of the present invention is to provide a system to monitor and control the functioning of the electric motor and the Electric Vehicle controller to ensure the safety working standards of the vehicle.

[0011] Another objective of the present invention is to provide a system that reduces the maximum power consumption at low state of charge to increase the efficiency/ mileage of the vehicle.

[0012] Yet another objective of the present invention is to detect overloading in vehicle without using any external weight sensor.

[0013] Yet another objective of the present invention is to provide a system that supersedes the user torque request to zero, thereby protecting the system from repetitive high current surges.
BRIEF DESCRIPTION OF DRAWING
[0014] The present invention will be better understood after reading the following detailed description of presently preferred aspects thereof with reference to the appended drawing, in which:
[0015] Figure 1 illustrates a system diagram of the present invention.

[0016] Figure 2 illustrates a flowchart of working of the energy management system by modulating the battery power deployed to the electric vehicle motor.

[0017] Reference Numerals for the components of the system are enlisted herein:

Sr. No. Component Reference Numerals
1 energy management system 100
2 electric motor 105
3 switching means 110
4 electric vehicle controller 115
5 Power Module 115a
6 Controller Module 115b
7 plurality of temperature sensors 120
8 battery pack 125
9 battery management system 130
10 Vehicle Display Unit 135
11 SOC Gauge 140
12 weight/ load sensor 145
13 Brake light indicator 150a
14 Reverse light indicator 150b
15 Power Pedal Unit 151
16 Handbrake 152
17 CAN bus 155

SUMMARY OF THE INVENTION
[0018] The present invention discloses a system for efficiently modulating the power deployment of a battery to an electric motor in an electric vehicle. The system includes an electric motor to produce a torque; a switching means to switch between different driving and direction modes; an electric vehicle controller to actively monitor and control the battery deployment; a plurality of temperature sensors including a RTD sensor and a NTC sensor to detect overheating of the motor and EV controller; an over temperature flag to receive the signal of overheating by the temperature sensors so as to supersedes the maximum power supply provided to the motor; a battery management system to actively monitor the battery condition and provide all the battery information to the electric vehicle controller. Further, the system monitors and modulates the battery supply situationally based on driver’s demand, overheating of the electric motor or EV controller, low SOC level, or overload failure.

DETAILED DESCRIPTION OF THE INVENTION
[0019] The following detailed description and embodiments set forth herein below are merely exemplary out of the wide variety and arrangement of instructions which can be employed with the present invention. The present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. All the features disclosed in this specification may be replaced by similar other or alternative features performing similar or same or equivalent purposes. Thus, unless expressly stated otherwise, they all are within the scope of the present invention.
[0020] Accordingly, those of ordinary skill in the art will recognize that various changes and modifications of the embodiments described herein can be made without departing from the scope of the invention. In addition, descriptions of well-known functions and constructions are omitted for clarity and conciseness.
[0021] The terms and words used in the following description and claims are not limited to the bibliographical meanings but are merely used to enable a clear and consistent understanding of the invention. Accordingly, it should be apparent to those skilled in the art that the following description of exemplary embodiments of the present invention are provided for illustration purpose only and not for the purpose of limiting the invention.
[0022] It is to be understood that the singular forms “a”, “an” and “the” include plural referents unless the context clearly dictates otherwise.
[0023] It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps, or components but does not preclude the presence or addition of one or more other features, integers, steps, components, or groups thereof.
[0024] The present invention provides a system and method for efficiently utilizing and managing the power generated by a battery of the electric vehicle, and thereby transmitting the generated power to the vehicle's prime mover, i.e., an electric motor. The energy management system actively monitors and controls the deployment of the battery energy to the electric motor.
[0025] In the present invention Figure 1 illustrates the system for managing the energy demand in an electric vehicle.
[0026] The energy management system (100) as per the present invention comprises of an electric motor (105), a switching means (110), an electric vehicle controller (115), a plurality of temperature sensor (120), a battery pack (125) and a battery management system (BMS) (130). In an embodiment each of these elements and the operation of the system will be described in more detail herein:
[0027] (a) Electric Motor (105): The electric motor/generator (105) provides the ignition power for the vehicle. The electric motor offers voltage ranging from 500W to 250kW. In the present invention, a high speed torque electric motor is utilized, and preferably a three phase air-cooled induction motor. The three phase air-cooled induction motor is utilized as a prime mover that provides the forward moving torque. As per a preferred embodiment, specifications of the electric motor are as follows:
Peak Power: 9 kW
Peak Torque: 45 Nm
RPM Range: 0 to 10,000 rpm
Battery Pack Voltage: 48V
[0028] (b) RNFB Switch (110): A switching means (110) provided in the present invention enables modulating the motor power as per the driver’s requirement. The switching means (110) is operated by the user to select whether he wants to drive vehicle in forward direction (F), reverse direction (R), in boost mode (B) or want to keep in idle in neutral mode (N). The switching means (110) such as, but not limited toa digital knob-type switch enables the driver to toggle between different direction modes and driving modes. The switching means (110) is connected to the Electric Vehicle (EV) controller, which enables the system to constantly evaluate the switching status and, hence, regulate the power of the motor on user’s request. The switching means (110) enables the driver to toggle between at least two driving mode, whilst also allows the driver to switch between two directional modes so as to control the direction of the electric vehicle i.e.,
(a) Forward mode, and
(b) reversal mode.
[0029] Toggling the switch (110) to the forward mode causes the system to set the vehicle's motion in the forward direction, whereas switching the direction mode to the reversal mode causes the system to set the vehicle's motion in the reverse direction. Further, the switching means (110) helps to switch between two driving modes by modulating the torque demanded by the motor. The switching means (110) controls the torque by switching between the two modes i.e., Boost mode and Forward Mode:
(i) Boost mode: Boost mode causes the motor to accelerate for providing maximum performance by the electric vehicle in the hilly region, which in turn quickly drains the battery. The boost mode allows the vehicle to trigger throttle in the system that helps in easily carrying heavy loads across sloped and hilly terrain. Further, the boost mode assists the vehicle to move in advancing/forward direction by rapidly accelerating the motor to desired speeds.
(ii) Forward mode. The system is switched to forward driving mode when the battery power transmitted to the electric motor is reduced and the motor is kept in a higher efficiency zone, allowing the vehicle to be driven at a constant speed. The forward driving mode extends the life of the battery by utilizing power more efficiently, allowing for greater vehicle range.
[0030] (c) an Electric Vehicle Controller (115): An Electric Vehicle Controller (115) is configured to control the operations of the electric vehicle (EV). The electric vehicle controller (115) is further divided into two section:
(i) Power Module (115a): A power module is an array of plurality of power electronic devices which helps in generating three phase supply for the induction motor via the direct (DC) power obtained from the battery.
(ii) Controller Module (115b): A controller module is configured with a microcontroller, which performs all the control function in the vehicle from controlling of the electric motor to the vehicle control.
[0031] (d) a Battery Pack (125): A battery pack (125) installed in the electric vehicle is a power storing device. In a preferred embodiment, the battery pack (125) configured in the electric vehicle have a capacity of at least 48 volts. The battery pack (125) is the sole power storage device fitted in the vehicle. In an exemplary embodiment of the present invention, a voltage sensor and current sensor may be electronically connected to the high voltage battery (125), so as to control the charging and discharging of the high voltage battery (125).
[0032] (e) a Vehicle Display Unit (135): The vehicle display unit (VDU) (135) is a display screen configured to display the speed of the vehicle and the state of charge (SOC) of the battery (125). In addition exemplary embodiment, the VDU (135) represents the status of the headlamps (150a, 150b), power pedal unit (151), turning indicators, handbrake (152), weight/ load sensor (145) and RFNB switch (110) mode. In the present invention, the VDU (135) is configured with a telematic unit for displaying vehicle location on a geographic map, and statistical information as per the usage of vehicle.
(f) Temperature Sensors (120): Electric motor and EV Controller like all electronic devices are prone to damage due to overheating. A continuous high power deployment may raise the motor temperature to dangerous levels where the copper winding insulation may fail causing an internal short circuit. For such scenarios, the EMS continuously monitors the motor and EV controller. The energy management system (100) of the present invention provides a safe temperature range in the electric vehicle by modulating the power deployment of the battery (125). The system employs a plurality of temperature sensors (120) selected from a group of but not limited to a Resistance Temperature Detector (RTD) and a Negative Temperature Coefficient (NTC) temperature sensor (120), which are embedded at various places within the Electric Motor, Battery Pack (125), and Controller, e.g., near the windings of the motor and the cells of the battery pack (125). These temperature sensors (120) continuously deliver the temperature reading of the respective device to the EV controller. Thus, the transmission of reading from temperature sensors (120) allows the controller to keep a track of temperature rise during the vehicle operation. In accordance with an exemplary embodiment of the present invention, the EV controller raises an over-temperature flag on exceeding the temperature limit over the designated limit, i.e., 160° Celsius for Electric motor & 80° Celsius for EV Controller. Further, on crossing/reaching the high temperature limit of the vehicle, the over-temperature flag supersedes the user’s power demand and lowers the maximum available power of the battery to prevent further over-heating of the system and thereby allowing the system to cool down to a safer level. At times of overheating or rise in temperature of the respective devices, the over-temperature flag transmits a signal to a display unit (135) for displaying notification regarding the low motor or battery power to the driver.
[0033] (g) a SOC Gauge (140): A gauge (140) representing the state of charge of the battery is provided to display lower battery health and remaining battery status to the driver.
[0034] (h) a Battery Management System (130): The energy management system of the present invention provides a battery pack (125) embraced with a Battery Management System (130) that helps in regulating the power deployment at lower or higher battery charge level. The system exercise extreme caution when charging a battery with a low state of charge (SOC), as it takes longer to fully charge the battery pack (125). The system continuously monitors the SOC status with the help of a Battery management System (BMS) (130).
[0035] The BMS (130) embraced to the electric vehicle battery is configured to monitor and control charging/ discharging of currents, state of health (SOH) and charging levels of battery pack (125) so as to promote safe operation of the electric vehicle. Though, the EV controller (115) works separately from the BMS (130) but communicate with each other via Controlled Area Network (CAN) bus (155). Furthermore, the EV controller (115) modulates the power deployed to the motor on detecting the lower SOC level. The BMS performs a variety of functions, including ensuring the battery’s safety and longevity, revealing State of Charge (SOC) and State of Heating (SOH), alerting the driver of high temperatures, cell imbalance, or calibration, and indicating end-of-life when the capacity falls below the user-set target threshold. As per the preferred embodiment of the present invention, when the EV controller (115) receives the communication from the BMS (130) indicating that the SOC level is less than 10%, the system overrides all torque demands made by the user and raises the Power limit flag. Further, the EV controller (115) forces the power limit flag to reduce the maximum available power for the motor and allows the vehicle to reach a safe charging point so as to enable the vehicle to use the battery with full potential.
[0036] (i) a Weight/Load Sensor (145): The energy management system of the present invention is designed for a specific cargo range. The system detects the cargo overload by using any external weight sensor (145)/ external load. If the cargo limit is exceeded or heavily loaded it may result in overloading. Overloading puts heavy load on mechanical component as well as the electric component of an electric vehicle, i.e., electric motor and Electric Vehicle (EV) Controller. The basic operation of EV controller (115) is to provide maximum torque on driver’s request until the vehicle accelerates. However, in case of overloading, the EV controller (115) constantly applies the torque and tries to start/accelerate the vehicle which may cause very high currents inside the system, potentially causing the system to damage. Therefore, in such times of overloading, the system provides information to the driver about the overload condition of the vehicle so as to ensure safety of the system. When the load exceeds the specified limit, the system locks the wheels and gradually reduces the battery power supply to the motor. The EV controller (115) supersedes the amount of throttle provided by the driver and the amount of torque provided by the motor to the wheels until the vehicle’s load limit reduces. The energy management system coupled to the EV controller (115) tracks the motor speed, throttle condition and the torque supplied to the wheels.
[0037] Figure 2 illustrates a flow diagram depicting the working of the energy management system in two conditions i.e., Boost mode and Forward Mode. The steps for the vehicle working in boost mode are:
i. switching on the vehicle;
ii. analyzing the RNFB switch (110) state i.e., whether the driver selected forward mode or boost mode;
iii. selecting boost mode;
iv. instructing the controller to check if any power or speed limits are imposed on the vehicle;
v. instructing the battery management system (130) to check status of the battery;
vi. evaluating the battery charge status to be optimum then no power limit is applied;
vii. evaluating the battery charge status to be low then required power limit activated;
viii. charging the battery pack (125) to optimum level; and
ix. evaluating the battery charge state and incase the battery is charged the system is directed to the step (ii).
[0038] Further, the steps for the vehicle working in forward mode are:
i. switching on the vehicle;
ii. analysing the RNFB switch (110) state i.e., whether the driver selected forward mode or boost mode;
iii. selecting forward mode;
iv. instructing the controller to check if any power or speed limits are imposed on the vehicle;
v. instructing the battery management system (130) to check status of the battery;
vi. evaluating the battery charge status to be optimum then no power limit is applied;
vii. evaluating the battery charge status to be low then required power limit activated;
viii. cooling down the battery pack (125) to optimum level; and
ix. evaluating the battery temperature and in case the battery is cooled down the system is directed to the step (ii).
[0039] As per an exemplary embodiment of the present invention, the energy management system of the present invention detects the overload condition of the vehicle. On applying the maximum torque by the motor to achieve the accelerated speed, if the motor speed remains still or lower than 150 RPM for more than 10 sec, the system counts such scenarios as overload condition. On detecting such overload condition, the EV controller (115) seizes the power supply for 2 seconds and indicates the overload fault to the driver on the display unit (135). However, the overload fault stays until the driver reduces the load to the designated limit to provide the vehicle with the nominal pace.
[0040] The various limitations of the system of the present invention for implementing the flow of the technology includes:
• Avoiding manual functioning of the vehicle as the driver cannot enable or disable any functioning of the system. However, automated functioning of the system controlled is controlled by an EV controller (115).
• During the overload failure, the system seizes the movement of vehicle by stopping the power supply to the motor till the time driver reduces the weight to the designated limit.
• If the SOC level goes below 10%, the BMS (130) on communicating to the EV controller (115) modulates the power deployment to power saving mode and overriding all torque demands by the driver.
• If the vehicle gets overheated, the EV controller (115) supersedes the user power demand and lowers the power generation so as to prevent further rise in temperature in the electric vehicle.
[0041] The advantages of the system of the present invention includes:
• The switching means provides the driver to switch between different driving modes and direction modes.
• An economic technology for increasing the longevity of the battery by monitoring and controlling the SOC and SOH through a battery management system.
• The modulation of motor torque as per the driver’s requirement.
• The EV controller includes the functionality to keep the motor under safe temperature range.
• The EV controller reduces the power at low SOC to increase the mileage of the vehicle and thereby allowing it to reach the nearby charging station.
• Detecting vehicle overloading to prevent the system from any failure or damage.

[0042] While this invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the scope of the appended claims.
, Claims:WE CLAIM:
1. An energy management system (100) in an electric vehicle, comprising:
• an electric motor (105) providing torque to wheels of the vehicle;
• a battery pack (125) supplying voltage to the electric motor (105) for generating torque;
• an electric vehicle (EV) controller (115) controlling operation of the vehicle;
• a battery management system (BMS) (130) monitoring the battery state of charge; and
• a vehicle display unit (135) displaying the system notifications to a driver,
wherein,
i. a switching means (110) selecting the driving modes of the electric vehicle;
ii. a plurality of temperature sensors (120) detecting the temperature of the electric vehicle;
iii. a plurality of load sensor (145) detecting overloading of the electric vehicle; and
iv. a state of charge gauge (140) embedded in the vehicle display unit (135).

2. The energy management system as claimed in claim 1, wherein the switching means (110) is an RNFB digital switch.

3. The energy management system as claimed in claim 1, wherein the RNFB switch (110) includes forward direction (F), reverse direction (R), in boost mode (B) and neutral mode (N).

4. The energy management system as claimed in claim 1, wherein the plurality of sensors are configured to be selected from but not limited to Resistance Temperature Detector (RTD) and Negative Temperature Coefficient (NTC).

5. The energy management system as claimed in claim 1, wherein the Resistance Temperature Detector (RTD) is connected with the electric motor (105) for determining the temperature.

6. The energy management system as claimed in claim 1, wherein Negative Temperature Coefficient (NTC) is connected with the Electric Vehicle Controller (115) for determining the temperature.

7. A method for controlling energy management system in an electric vehicle as claimed in claim 1 comprises the following steps:
• selecting the direction of movement of the vehicle;
• assessing the direction of movement of the vehicle;
• assessing and monitoring the state of charge of the battery; and
• assessing the load on vehicle.

8. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein the direction of the movement of vehicle is selected through the switching means (110) manually by the user.

9. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein the direction of the movement of vehicle is selected as Boost mode comprising the following steps:
i. switching on the vehicle;
ii. analyzing the RNFB switch (110) state i.e., whether the driver selected forward mode or boost mode;
iii. selecting boost mode;
iv. switching between boost and continuous modes through the switching means (110), wherein when the switch is in the boost mode, the system instructs the controller to check circumvent, if any power or speed limits are imposed on by the vehicle;
v. instructing the battery management system (130) to check status of the battery;
vi. evaluating the battery charge status to be optimum then no power limit is applied;
vii. evaluating the battery charge status to be low then required power limit activated;
viii. charging the battery pack (125) to optimum level; and
ix. evaluating the battery charge state and incase the battery is charged the system is directed to the step (ii).

10. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein the direction of the movement of vehicle is selected as Forward mode comprising the following steps:
i. switching on the vehicle;
ii. analysing the RNFB switch state i.e., whether the driver selected forward mode or boost mode;
iii. selecting forward mode;
iv. instructing the vehicle controller to check if any power or speed limits are imposed on the vehicle;
v. instructing the battery management system (130) to check status of the battery;
vi. evaluating the battery charge status to be optimum then no power limit is applied;
vii. evaluating the battery charge status to be low then required power limit activated;
viii. cooling down the battery pack (125) to optimum level; and
ix. evaluating the battery temperature and in case the battery is cooled down the system is directed to the step (ii).

11. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein the battery management system (130) actively controls and monitors the battery status.

12. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein electric vehicle controller actively monitors the status of the switching means (110) to regulate power generated by the electric motor (105).

13. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein the electric vehicle controller (115), on detecting a overloading of vehicle reduces the battery power supply to the electric motor.

14. The method for controlling energy management system in an electric vehicle as claimed in claim 7, wherein the SOC gauge (140) displays the state of charge of battery.