Security mechanisms for electric motors and associated systems
The present disclosure relates to security mechanisms for electric motors and associated systems. For example, the present technology includes a powertrain assembly having (1) a motor having multiple sets of coils; (2) a drive circuitry electrically coupled to the multiple sets of coils; and (3) a security unit electrically coupled to the drive circuitry and the multiple sets of coils. The security unit is configured to short-circuit at least one set of the multiple sets of coils responsive to a signal from a controller. The signal indicates that the motor is, or has been, turned off.
1. A hub apparatus for driving a vehicle, comprising:
a motor having multiple sets of coils;
a drive circuitry electrically coupled to the multiple sets of coils; and
a security unit electrically coupled to the drive circuitry and the multiple sets of coils, the security unit having a conducive plate being configured to be moved by an actuator toward the multiple sets of coils, so as to short-circuit at least one set of the multiple sets of coils, the actuator being moved responsive to a signal indicating that the motor is turned off, wherein, after the actuator is moved, a testing signal is sent to the drive circuitry so as to confirm that at least one set of the multiple sets of coils has been short-circuited,
wherein the motor includes a stator assembly having the multiple sets of coils, and
wherein the motor comprises a housing rotatably coupled to a shaft, and wherein the stator assembly is positioned inside the housing and coupled to the shaft, and wherein the stator assembly is electrically coupled to a battery assembly enclosed in the stator assembly, and wherein the stator assembly includes a coil assembly including the multiple sets of coils, and wherein the coil assembly is circumferentially positioned about the shaft.
2. The hub apparatus of claim 1 , wherein the actuator comprises a solenoid valve configured to move the conductive plate to short-circuit the at least one set of the multiple sets of coils.
3. The hub apparatus of claim 1 , wherein the actuator comprises a linear motor configured to move the conductive plate to short-circuit the at least one set of the multiple sets of coils.
4. The hub apparatus of claim 1 , wherein the security unit comprises a switch configured to short-circuit the at least one set of the multiple sets of coils, and wherein the switch comprises:
a mechanical switch configured to short-circuit the at least one set of the multiple sets of coils; or
a transistor-based switch configured to short-circuit the at least one set of the multiple sets of coils.
5. The hub apparatus of claim 1 , wherein the at least one short-circuited set of coils is configured to generate, in response to a change of a magnetic field caused by a rotation of a rotor assembly, a torque in a reverse direction of the rotation of the rotor assembly.
6. The hub apparatus of claim 5 , further comprising:
a locking device configured to at least partially prevent the rotor assembly from rotating relative to the stator assembly, the locking device having a stopper and an actuator coupled to the stopper, the stopper being configured to be moved by the actuator.
7. The hub apparatus of claim 1 , wherein the motor includes a rotor assembly having the multiple sets of coils, and wherein the at least one short-circuited set of coils is configured to generate, in response to a change of a magnetic field caused by a rotation of the rotor assembly, a torque in a reverse direction of the rotation of the rotor assembly.
8. The hub apparatus of claim 1 , wherein the drive circuitry is configured to control the multiple sets of coils so as to generate a three-phase alternating current.
9. The hub apparatus of claim 1 , further comprising a relay electrically coupled between multiple sets of coils and the security unit.
10. The hub apparatus of claim 9 , wherein the relay is configured to form an open circuit when a current passing through the multiple sets of the coils exceeds a threshold value.
11. The hub apparatus of claim 1 , wherein the signal indicating that the motor is turned off also indicates that the motor has been turned off for a predetermined time period.
12. A vehicle with a security system, the vehicle comprising:
a motor having multiple sets of coils;
a controller electrically coupled to the motor;
a drive circuitry electrically coupled to the multiple sets of coils; and
a security system having a security unit electrically coupled to the drive circuitry and the multiple sets of coils, the security unit having a conductive plate configured to be moved by an actuator toward the multiple sets of coils so as to short-circuit at least one set of the multiple sets of coils, the actuator being moved responsive to a signal indicating that the motor is turned off, wherein, after the actuator is moved, a testing signal is sent to the drive circuitry so as to confirm that at least one set of the multiple sets of coils has been short-circuited,
wherein the motor includes a rotor assembly and a stator assembly, and wherein the security system further comprises:
a locking device configured to at least partially prevent the rotor assembly from rotating relative to the stator assembly, the locking device having a stopper and an actuator coupled to the stopper, the stopper being configured to be moved by the actuator,
wherein the stator assembly comprises a coil assembly including the multiple sets of coils, and wherein the coil assembly is circumferentially positioned about a shaft coupled to the rotor assembly.
13. The vehicle of claim 12 , wherein the actuator comprises a solenoid valve configured to move the conductive plate to short-circuit the at least one set of the multiple sets of coils.
14. The vehicle of claim 12 , further comprising:
a wheel driven by the motor, wherein the motor is configured to drive the wheel via a power transmission component.
15. The vehicle of claim 12 , further comprising a wheel driven by the motor, wherein a rotor assembly of the motor is fixedly coupled to the wheel.
16. A method for securing a vehicle, comprising:
receiving, by a controller, a signal regarding turning off the vehicle;
instructing, by the controller, an actuator of a security unit to move a conductive plate of the security unit toward plurality of coils of a motor in the vehicle so as to short-circuit at least one the plurality of coils of the motor;
instructing, by the controller, a circuit controller to send a testing signal to a drive circuitry electrically coupled to the plurality of coils, so as to verify whether at least one of the plurality of coils is short-circuited;
entering a hibernation mode when receiving a confirmation signal that part or all of the plurality of coils are short-circuited; and
activating, by the controller, a locking device by instructing an actuator of the locking device to move a stopper of the locking device to contact a rotor assembly of the motor of the vehicle, when the control receives the confirmation signal that part or all of the plurality of coils are short-circuited,
wherein the plurality of coils is circumferentially positioned about a shaft coupled to the rotor assembly.
17. The method of claim 16 , further comprising:
sending a notification to a user mobile device or a display on the vehicle if the confirmation is not successfully received: and
entering the hibernation mode after sending the notification.