Description:FIELD OF THE INVENTION
[001] The present invention relates to control of a traction motor. More particularly, the present invention relates to system and method for controlling a traction motor for providing braking torque for a vehicle.

BACKGROUND OF THE INVENTION
[002] With the advancement in vehicle technologies, there is greater focus on enhancement of driver assistance, and on improving the overall driving experience. Most modern-day electric or hybrid vehicles are provided with regenerative braking wherein energy is recovered during braking, and the energy is stored back in the battery. Regenerative braking recovers some of the kinetic energy that would otherwise turn into heat and instead converts it into electricity. A number of conventional techniques exist for control of the regenerative braking. It is well understood that when regenerative braking contribution is set at a significant value, the same leads to better mileage and better response in braking control and overall vehicle behaviour becomes better.
[003] However, regenerative braking for charging the electric vehicle or hybrid vehicle battery also depends on the SoC (State of Charge) of the batteries. In existing systems, the regenerative braking is set to automatically switch off whenever SoC reaches a threshold value, for example, 90% or higher, for better battery life maintenance. The problem with this limitation is that this automatic switch off of regenerative braking can suddenly occur at any point of time when the SoC crosses the threshold, even during usage / driving situation. This abrupt switching off of the regenerative braking leads to a sudden drop in braking response with respect to any given input to the foundation brake system and thereby sudden loss of vehicle control. This results in significant lack of rider confidence in the braking system and thereby becomes a major issue in road safety. Further, this loss of regenerative braking becomes a further safety risk when the vehicle is in on an uphill climb.
[004] Certain existing systems for regenerative braking control do address the issue of preventing overcharging of battery by switching off regenerative braking by various techniques. Other existing systems focus on continuation of regenerative braking when the SoC of the battery is beyond the threshold value by dumping the regenerated kinetic energy by means of a rheostatic resistor, thus not leading to any useful work output. This also leads to addition of parts and overall weight of the vehicle. However, none of the prior arts address the issue of loss in braking response and loss of vehicle control due to switching off of regenerative braking when the SoC crosses a certain threshold.
[005] Thus, there is a need in the art for a system and method for controlling a traction motor which addresses at least the aforementioned problems.

SUMMARY OF THE INVENTION
[006] In one aspect, the present invention relates to a system for controlling a traction motor. The system has a power source, the traction motor and a control unit. The control unit is configured to: detect a braking operation and determine a state of charge of the power source. The control unit is further configured to operate the traction motor to receive torque from a wheel of the vehicle and provide electrical energy to the power source, if during the braking operation, the state of charge of the power source is lower than a first predetermined value. The control unit is further configured to receive electrical energy from the power source and operate the traction motor to produce a reverse torque, thereby providing braking torque to the wheel, if during the braking operation, the state of charge of the power source is equal to or higher than the first predetermined value.
[007] In an embodiment of the present invention, the control unit has a first phase high side MOSFET and a first phase low side MOSFET, a second phase high side MOSFET and a second phase low side MOSFET, and a third phase high side MOSFET and a third phase low side MOSFET.
[008] In a further embodiment of the present invention, the control unit is configured to detect a speed of the vehicle, if the state of charge of the power source is equal to or higher than the first predetermined value. The control unit is further configured to switch ON the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET for a predetermined actuation angle, and switch OFF the first phase high side MOSFET, the second phase high side MOSFET and the third phase high side MOSFET for a predetermined time, if the speed of the vehicle is lower than a second predetermined value, to operate the traction motor to produce the reverse torque, thereby providing braking torque to the wheel of the vehicle.
[009] In a further embodiment of the invention, the control unit is configured to switch ON the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET for a predetermined actuation angle, and switch OFF the first phase high side MOSFET, the second phase high side MOSFET and the third phase high side MOSFET for a predetermined time, if the speed of the vehicle is higher than or equal to the second predetermined value, to operate the traction motor to produce the reverse torque, thereby providing braking torque to the wheel of the vehicle. The control unit is also configured to detect a temperature of the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET.
[010] In a further embodiment of the invention, the control unit is configured to switch ON the first phase high side MOSFET, the second phase high side MOSFET and the third phase high side MOSFET for a predetermined actuation angle, and switch OFF the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET for a predetermined time, if the temperature of the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET is equal to or higher than a third predetermined value, to operate the traction motor to produce the reverse torque, thereby providing braking torque to the wheel of the vehicle.
[011] In another aspect, the present invention provides a method for controlling a traction motor for providing a braking torque for a vehicle. The method has the steps of detecting a braking operation of the vehicle; determining a state of charge of a power source of the vehicle; operating the traction motor to receive torque from a wheel of the vehicle and provide electrical energy to the power source of the vehicle, if during the braking operation, the state of charge of the power source is lower than a first predetermined value; and receiving electrical energy from the power source and operate the traction motor to produce a reverse torque, thereby providing braking torque to the wheel of the vehicle, if during the braking operation, the state of charge of the power source is equal to or higher than the first predetermined value.
[012] In an embodiment of the invention, the method has the steps of: detecting a speed of the vehicle, if the state of charge of the power source is equal to or higher than the first predetermined value; and switching ON a first phase low side MOSFET, a second phase low side MOSFET and a third phase low side MOSFET for a predetermined actuation angle, and switching OFF a first phase high side MOSFET, a second phase high side MOSFET and a third phase high side MOSFET for a predetermined time, if the speed of the vehicle is lower than a second predetermined value, to operate the traction motor to produce the reverse torque, thereby providing braking torque to the wheel of the vehicle.
[013] In an embodiment of the invention, the method has the steps of switching ON the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET for a predetermined actuation angle, and switching OFF the first phase high side MOSFET, the second phase high side MOSFET and the third phase high side MOSFET for a predetermined time, if the speed of the vehicle is higher than or equal to the second predetermined value, to operate the traction motor to produce the reverse torque, thereby providing braking torque to the wheel of the vehicle; and detecting a temperature of the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET.
[014] In a further embodiment of the invention, the method has the steps of: switching ON the first phase high side MOSFET, the second phase high side MOSFET and the third phase high side MOSFET for a predetermined actuation angle, and switching OFF the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET for a predetermined time, if the temperature of the first phase low side MOSFET, the second phase low side MOSFET and the third phase low side MOSFET is equal to or higher than a third predetermined value, to operate the traction motor to produce the reverse torque, thereby providing braking torque to the wheel of the vehicle.

BRIEF DESCRIPTION OF THE DRAWINGS
[015] Reference will be made to embodiments of the invention, examples of which may be illustrated in accompanying figures. These figures are intended to be illustrative, not limiting. Although the invention is generally described in context of these embodiments, it should be understood that it is not intended to limit the scope of the invention to these particular embodiments.
Figure 1 illustrates a system for controlling a traction motor for providing braking torque for a vehicle, in accordance with an embodiment of the present invention.
Figure 2 illustrates a control unit of the system for controlling the traction motor, in accordance with an embodiment of the present invention.
Figure 3 illustrates a method for controlling a traction motor for providing braking torque for a vehicle, in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION
[016] The present invention relates to control of a traction motor. More particularly, the present invention relates to system and method for controlling a traction motor for providing braking torque for a vehicle. The system and method of the present invention are typically used in a vehicle such as a two wheeled electric or hybrid vehicle, or a three wheeled electric or hybrid vehicle, or a four wheeled electric or hybrid vehicle, or other multi-wheeled electric or hybrid vehicles as required.
[017] Figure 1 illustrates a system 100 for controlling a traction motor 120 for providing a braking torque to a vehicle. As illustrated, the system 100 has a power source 110. In an embodiment, the power source 110 comprises a battery (not shown) or battery pack (not shown) made up of multiple batteries. The system 100 further has the traction motor 120 that is electrically connected to the power source 110 of the vehicle (not shown). The traction motor 120 is operatively connected to at least one wheel 130 of the vehicle. Thus, during a traction operation, the power source 110 provides electrical power to the traction motor 120 which then provides the traction force or torque to the at least one wheel 130 of the vehicle. During a braking operation, the traction motor 120 converts the kinetic energy of the at least one wheel 130 into electrical energy and the electrical energy is provided for charging of the power source 110. In an embodiment, the traction motor 120 is capable of being operatively connected to more than one wheels of the vehicle through a transmission system (not shown), or the system 100 has more than one traction motors 120, each traction motor 120 being connected to each of the wheels (130) of the vehicle.
[018] As further illustrated in Figure 1, the system 100 has a control unit 140. The control unit 140 is connected to the traction motor 120 and is configured to control the operation of the traction motor 120. The control unit 140 is configured to detect a braking operation of the vehicle. In that, in an embodiment, the control unit 140 is connected to a brake switch 150 of the vehicle. When a brake pedal or brake lever (not shown) is depressed or activated, the brake switch 150 is activated to turn on a brake light. The brake switch 150 is in communication with the control unit 140 and the control unit 140 detects the activation of the brake switch 150, thus detecting a braking operation of the vehicle. The control unit 140 is also configured to determine a state of charge of the power source 110. Thus, the control unit 140 determines that whether the state of charge of the power source 110 is lower than or equal to or higher than a first predetermined value.
[019] Further, the control unit 140 is configured to operate the traction motor 120 to receive torque from the wheel 130 of the vehicle and provide electrical energy to the power source 110 of the vehicle, if during the braking operation, the state of charge of the power source 110 is lower than the first predetermined value. Thus, if the control unit 140 during a braking operation, determines the state of charge of the power source 110 to be lower than the first predetermined value, the control unit 140 operates the traction motor 120 to receive the torque from the wheel 130 and provide electrical energy to the power source 110, thus achieving regenerative braking.
[020] If during the braking operation, the control unit 140 determines the state of charge of the power source to be equal to or higher than the first predetermined value, the regenerative braking as explained above is not executed to prevent the power source 110 from overcharging and for better power source 110 life. However, to prevent loss of braking response or vehicle control during this condition when during the braking operation the state of charge of the power source 110 is equal to or higher than the first predetermined value, the control unit 140 is configured to receive electrical energy from the power source 110 and operate the traction motor 120 to produce a reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. Thus, a reverse torque is produced by the traction motor 120 which has an effect similar to regenerative braking on the braking operation, thus ensuring that the braking characteristics or the resultant braking response remains consistent irrespective of the state of charge of the power source 110. This ensures reliable and consistent braking operation which leads to better rider experience and safer riding conditions. In an embodiment, the first predetermined value of the state of charge of the power source 110 is 90%. Thus, in operation, during braking operation, if the state of charge is lower than 90%, the control unit 140 executes regenerative braking by operating the traction motor 120 to receive the torque from the wheel 130 and provide electrical energy to the power source 110. Conversely, during braking operation, if the state of charge is equal to or higher than 90%, the control unit 140 receives electrical energy from the power source 110 and operates the traction motor 120 to produce a reverse torque in order to retain the same resultant braking response and vehicle control while braking with constant effort.
[021] In an embodiment, as illustrated in Figure 2, the control unit 140 has a first phase high side metal-oxide-semiconductor field-effect transistor or MOSFET 140A and a first phase low side MOSFET 140A’. The control unit 140 further has a second phase high side MOSFET 140B and a second phase low side MOSFET 140B’. The control unit 140 further has a third phase high side MOSFET 140C and a third phase low side MOSFET 140C’. In that, the high side MOSFETs 140A, 140B, 140C are connected to a positive terminal of the power source 110 and the low side MOSFETs 140A’, 140B’, 140C’ are connected to a negative terminal of the power source 110. Further, the first phase, the second phase and the third phase MOSFETs are respectively connected to phase coils of the traction motor 120 to control the traction motor 120 in the three phases.
[022] The reverse torque to be produced by the traction motor 120 also depends on the speed of the vehicle. To account for this, in an embodiment, the control unit 140 is configured to detect a speed of the vehicle, if the state of charge of the power source 110 is equal to or higher than the first predetermined value. If the detected speed of the vehicle is lower than a second predetermined value, the control unit 140 is configured to switch ON the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ for a predetermined actuation angle, and switch OFF the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. In an embodiment, the second predetermined value of the speed of the vehicle is 25Kmph. At lower vehicle speeds, such as when speed is lower than the second predetermined value, the current required to be flowing through the MOSFETs is lower to produce the reverse torque, and thus the MOSFETs are not under any thermal stress.
[023] However, the above technique, especially when executed at high vehicle speeds, such as speeds higher than or equal to the second predetermined value, may lead to an increase in the temperature of the low side MOSFETs. Thus, if the detected speed of the vehicle is equal to or higher than the second predetermined value, the control unit 140 is configured to switch ON the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ for a predetermined actuation angle, and switch OFF the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. In addition, to address the issue of higher temperature of the low side MOSFETs, if the detected speed is equal to or higher than the second predetermined value, the control unit 140 is also configured to detect a temperature of the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’.
[024] In an embodiment, if the control unit 140 determines the temperature of the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ to be equal to or higher than a third predetermined value, the control unit 140 adjust for the same as follows. To provide the reverse torque in such a condition, the control unit 140 is configured to switch ON the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C for a predetermined actuation angle, and switch OFF the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. Thus, in effect, if the temperature of the switched ON low side MOSFETs 140A’, 140B’, 140C’ crosses the third predetermined value, the reverse torque through operation of the traction motor 120 is produced through high side MOSFETs 140A, 140B, 140C instead of the low side MOSFETs 140A’, 140B’, 140C’, thus reducing the thermal stress of the low side MOSFETs 140A’, 140B’, 140C’ as well as the high side MOSFETs 140A, 140B, 140C. Further, by having a control over the net circulating power and/or circulating current in the high side MOSFETs 140A, 140B, 140C and the low side MOSFETs 140A’, 140B’, 140C’, the amount of reverse torque can also be controller, thus defining the requisite braking effect.
[025] In another aspect, the present invention relates to a method 200 for controlling a traction motor 120 for providing braking torque for a vehicle. The method steps involved in the method 200 for controlling the traction motor 120 are illustrated in Figure 3, in accordance with an embodiment of the present invention. As illustrated, at step 202, the braking operation of the vehicle is detected by the control unit 140. At step 204, a state of charge of the power source 110 of the vehicle is detected by the control unit 140. The control unit 140 particularly determines whether the state of charge of the power source 110 is lower than or equal to or higher than a first predetermined value. If at step 204, during the braking operation, the state of charge of the power source 110 is determined to be lower than the first predetermined value, the method 200 moves to step 222, wherein the traction motor 120 is operated by the control unit 140 to receive torque from a wheel 130 of the vehicle and provide electrical energy to the power source 110 of the vehicle, for regenerative braking. Thereafter at step 224, the control unit 140 again checks for the braking operation, and if the braking operation is detected i.e. brake switch 150 is detected to be ON, the method 200 reverts to step 222 for continuous operation, and if the braking operation is not detected i.e. brake switch 150 is detected to be OFF, the process is stopped at step 226 till the braking operation is detected.
[026] If at step 204, the during the braking operation, the state of charge of the power source 110 is determined to be equal to or higher than the first predetermined value, the method 200 moves to step 206. At step 206, a speed of the vehicle is detected by the control unit 140. At step 206, the control unit 140 determines that whether the speed of the vehicle is higher than or equal to or lower than a second predetermined value. If at step 206, the speed of the vehicle is determined to be lower than the second predetermined value, the method 200 moves to step 216. At step 216, the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ are switched ON by the control unit 140 for a predetermined actuation angle, and the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C for switched OFF by the control unit 140 for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. Thereafter at step 218, the control unit 140 again checks for the braking operation, and if the braking operation is detected i.e. brake switch 150 is detected to be ON, the method 200 reverts to step 206 for continuous operation, and if the braking operation is not detected i.e. brake switch 150 is detected to be OFF, the process is stopped at step 220 till the braking operation is detected.
[027] If at step 206, the speed of the vehicle is determined to be equal to or higher than the second predetermined value, the method 200 moves to step 208. At step 208, the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ are switched ON by the control unit 140 for a predetermined actuation angle, and the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C are switched OFF by the control unit 140 for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. Thereafter, the method 200 moves to step 210.
[028] At step 210, a temperature of the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ is detected by the control unit 140. Thus, at step 210, the control unit 140 determines that whether the temperature of the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ is lower than or equal to or higher than a third predetermined value. If at step 210, the temperature of the low side MOSFETs 140A’, 140B’, 140C’ is determined to be lower than the third predetermined value, the method moves to step 214. At step 214, the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ are switched ON by the control unit 140 for a predetermined actuation angle, and the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C are switched OFF by the control unit 140 for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. After step 214, the method 200 reverts to step 206 for continuous operation.
[029] If at step 210, the temperature of the low side MOSFETs 140A’, 140B’, 140C’ is determined to be equal to or higher than the third predetermined value, the method moves 200 moves to step 212. At step 212, the first phase high side MOSFET 140A, the second phase high side MOSFET 140B and the third phase high side MOSFET 140C are switched ON by the control unit 140 for a predetermined actuation angle, and the first phase low side MOSFET 140A’, the second phase low side MOSFET 140B’ and the third phase low side MOSFET 140C’ are switched OFF by the control unit 140 for a predetermined time, to operate the traction motor 120 to produce the reverse torque, thereby providing braking torque to the wheel 130 of the vehicle. After step 212, the method 200 reverts to step 206 for continuous operation.
[030] Advantageously, the present invention provides a system and a method for controlling a traction motor for providing braking torque to a vehicle such that during a braking operation, a reverse torque is produced when the state of charge of the power source is above the first predetermined value and the regenerative braking is stopped. The reverse torque has an effect on the braking characteristics similar to regenerative braking, and thus there is no loss in braking response and no loss of vehicle control due to switching off of regenerative braking when the SoC crosses a certain threshold. Thus, the rider does not feel any difference in the braking feel or braking response when the regenerative braking is on as well as when the regenerative braking is off. This ensuring more trust and reliability in the braking system by the rider, and thus ensuring safer riding conditions.
[031] Further, since the present invention eliminates the requirement of rheostatic resistors for dumping of regenerative power, the need for additional elements is eliminated, leading to lower complexity and lower costs. The present invention does not require the aid of any additional hardware or any external power source to for provision of the reverse torque for same braking effect. The present invention also ensures that there is no loss of braking operation or no detriment to braking characteristics or braking response, even when the state of charge is high and the vehicle is in an uphill climb, which enhances the vehicle safety.
[032] Consistent braking characteristics and braking response irrespective of the state of charge of the power source, as provided by the present invention allows for consistent confidence levels of the rider in the braking system, which leads to an overall better and safer riding experience.
[033] While the present invention has been described with respect to certain embodiments, it will be apparent to those skilled in the art that various changes and modification may be made without departing from the scope of the invention as defined in the following claims.
List of Reference Numerals
100: System for Controlling a Traction Motor

110: Power Source
120: Traction Motor
130: Wheel
140: Control Unit
140A: First phase high side MOSFET
140B: Second phase high side MOSFET
140C: Third phase high side MOSFET
140A’: First phase low side MOSFET
140B’: Second phase low side MOSFET
140C’: Third phase low side MOSFET
150: Brake Switch  
, Claims:1. A system (100) for controlling a traction motor (120) for providing braking torque for a vehicle, the system (100) comprising:
a power source (110);
the traction motor (120) being electrically connected to the power source (110) of the vehicle, and the traction motor (120) being operatively connected to at least one wheel (130) of the vehicle; and
a control unit (140), the control unit (140) being configured to:
detect a braking operation of the vehicle;
determine a state of charge of the power source (110);
operate the traction motor (120) to receive torque from the wheel (130) of the vehicle and provide electrical energy to the power source (110) of the vehicle, if during the braking operation, the state of charge of the power source (110) being lower than a first predetermined value; and
receive electrical energy from the power source (110) and operate the traction motor (120) to produce a reverse torque, thereby providing braking torque to the wheel (130) of the vehicle, if during the braking operation, the state of charge of the power source (110) being equal to or higher than the first predetermined value.

2. The system (100) as claimed in claim 1, wherein the control unit (140) comprises:
a first phase high side MOSFET (140A) and a first phase low side MOSFET (140A’);
a second phase high side MOSFET (140B) and a second phase low side MOSFET (140B’); and
a third phase high side MOSFET (140C) and a third phase low side MOSFET (140C’).

3. The system (100) as claimed in claim 2, wherein the control unit (140) being configured to:
detect a speed of the vehicle, if the state of charge of the power source (110) being equal to or higher than the first predetermined value; and
switch ON the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) for a predetermined actuation angle, and switch OFF the first phase high side MOSFET (140A), the second phase high side MOSFET (140B) and the third phase high side MOSFET (140C) for a predetermined time, if the speed of the vehicle being lower than a second predetermined value, to operate the traction motor (120) to produce the reverse torque, thereby providing braking torque to the wheel (130) of the vehicle.

4. The system (100) as claimed in claim 3, wherein the control unit (140) being configured to:
switch ON the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) for a predetermined actuation angle, and switch OFF the first phase high side MOSFET (140A), the second phase high side MOSFET (140B) and the third phase high side MOSFET (140C) for a predetermined time, if the speed of the vehicle is higher than or equal to the second predetermined value, to operate the traction motor (120) to produce the reverse torque, thereby providing braking torque to the wheel (130) of the vehicle; and
detect a temperature of the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’).

5. The system (100) as claimed in claim 4, wherein the control unit (140) being configured to:
switch ON the first phase high side MOSFET (140A), the second phase high side MOSFET (140B) and the third phase high side MOSFET (140C) for a predetermined actuation angle, and switch OFF the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) for a predetermined time, if the temperature of the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) is equal to or higher than a third predetermined value, to operate the traction motor (120) to produce the reverse torque, thereby providing braking torque to the wheel (130) of the vehicle.

6. A method (200) for controlling a traction motor (120) for providing braking torque for a vehicle, the method (200) comprising the steps of:
detecting, by a control unit (140), a braking operation of the vehicle;
determining, by the control unit (140), a state of charge of a power source (110) of the vehicle;
operating, by the control unit (140), the traction motor (120) to receive torque from a wheel (130) of the vehicle and provide electrical energy to the power source (110) of the vehicle, if during the braking operation, the state of charge of the power source (110) is lower than a first predetermined value; and
receiving, by the control unit (140), electrical energy from the power source (110) and operate the traction motor (120) to produce a reverse torque, thereby providing braking torque to the wheel (130) of the vehicle, if during the braking operation, the state of charge of the power source (110) is equal to or higher than the first predetermined value.

7. The method (200) as claimed in claim 6, comprising the steps of:
detecting, by the control unit (140), a speed of the vehicle, if the state of charge of the power source (110) is equal to or higher than the first predetermined value; and
switching, by the control unit (140), ON a first phase low side MOSFET (140A’), a second phase low side MOSFET (140B’) and a third phase low side MOSFET (140C’) for a predetermined actuation angle, and switching OFF a first phase high side MOSFET (140A), a second phase high side MOSFET (140B) and a third phase high side MOSFET (140C) for a predetermined time, if the speed of the vehicle is lower than a second predetermined value, to operate the traction motor (120) to produce the reverse torque, thereby providing braking torque to the wheel (130) of the vehicle.

8. The method (200) as claimed in claim 7, comprising the steps of:
switching, by the control unit (140), ON the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) for a predetermined actuation angle, and
switching OFF the first phase high side MOSFET (140A), the second phase high side MOSFET (140B) and the third phase high side MOSFET (140C) for a predetermined time, if the speed of the vehicle is higher than or equal to the second predetermined value, to operate the traction motor (120) to produce the reverse torque, thereby providing braking torque to the wheel (130) of the vehicle; and
detecting, by the control unit (140), a temperature of the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’).

9. The method (200) as claimed in claim 8, comprising the steps of:
switching, by the control unit (140), ON the first phase high side MOSFET (140A), the second phase high side MOSFET (140B) and the third phase high side MOSFET (140C) for a predetermined actuation angle, and
switching OFF the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) for a predetermined time, if the temperature of the first phase low side MOSFET (140A’), the second phase low side MOSFET (140B’) and the third phase low side MOSFET (140C’) is equal to or higher than a third predetermined value, to operate the traction motor (120) to produce the reverse torque, thereby providing braking torque to the wheel (130) of the vehicle.