Electric vehicle motor torque safety monitor
AssigneeAtieva, Inc.
InventorYifan TANG
Life of this patent
Estimating the term…
Abstract
A safety system for an electric motor controller is provided. The safety system includes a torque safety monitor having a first processor distinct from a second processor of a main motor controller. The first processor is configured to one of decrease or shut down AC (alternating current) power, sent from a DC/AC (direct current to alternating current) inverter to an electric motor, in response to an estimated torque of the electric motor differing from a commanded torque associated with the main motor controller by more than a set amount.
Claims20
A safety system for an electric motor controller, comprising:
- a torque safety monitor having a first processor distinct from a second processor of a main motor controller;
- and
- the first processor configured to one of decrease or shut down AC (alternating current) power, sent from a DC/AC (direct current to alternating current) inverter to an electric motor, in response to an estimated torque of the electric motor differing from a commanded torque associated with the main motor controller by more than a set amount.
A safety system for a vehicle, comprising:
- a torque safety monitor, distinct from a main motor controller of a vehicle;
- the torque safety monitor including a torque estimator that produces an estimated torque from inputs including a measurement of a stator current of a motor and a rotational speed of the motor, the motor controlled by the main motor controller via the torque safety monitor;
- the torque safety monitor including a torque monitor that performs a comparison of the estimated torque and a commanded torque, the commanded torque an input to the main motor controller;
- and
- the torque safety monitor including a status and failure processor operable to output a protection directive based on the comparison of the estimated torque and the commanded torque, the protection directive acting to modify switching signals from the main motor controller to decrease AC (alternating current) power delivered to the motor.
A method of monitoring an electric motor, comprising:
- comparing an estimated torque of an electric motor to a commanded torque;
- and
- producing reduced power level switching signals, for a DC/AC (direct current to alternating current) inverter, from switching signals received from a main motor controller, in response to the estimated torque of the electric motor differing from the commanded torque by a preset amount.
Dependencies are inferred from the claim text.