Motiv Power Systems, Inc.

Tai-Sik Hwang

James Michael Castelaz

Justin Tomlin

Elias Stein

A vehicle includes a vehicle mass estimator circuit. The vehicle mass estimator circuit is configurable to estimate a mass of vehicle during real-time operation of the vehicle without employing a scale or dedicated mass sensing system. The vehicle mass estimator circuit generates the vehicle mass Mfrom: (1) an estimated torque or sensed torque, (2) an estimated motor angular velocity or sensed motor angular velocity, and (3) sensed acceleration or without any sensed acceleration. In one embodiment, the vehicle mass estimator circuit senses motor current during vehicle operation and estimates a mass of the vehicle using the motor current without any dedicated acceleration sensor such as an accelerometer. A motor angular velocity is estimated from the motor current. In another embodiment, the vehicle mass estimator circuit senses motor current during vehicle operation and estimates a mass of the vehicle using the motor current and acceleration information provided by an accelerometer.

Real-time reporting and estimating of mass of vehicles using drive characteristics

A controller generates a target motor torque and target accessory power information during operation of an electric vehicle. The target motor torque and target accessory power information maintain a DC-link of the electric vehicle powertrain within a safe DC-link operating range. The DC-link has a DC-link voltage that is used to supply an accessory device and a motor. The accessory device is disposed on the electric vehicle and includes vehicle indictors, hydraulics, or any other accessory involved in the operation of the vehicle. The motor drives the vehicle. The controller receives the DC-link voltage, motor speed, desired output torque information, desired accessory power information, and the safe DC-link operating range and generates therefrom the target motor torque and the target accessory power information.

Powering electric vehicle accessory devices from back EMF generated by an electric motor

Pre-loading drivetrain to minimize electric vehicle rollback and increase drive responsiveness. In an exemplary embodiment, a method includes (a) detecting that an electric vehicle is stationary, a brake is engaged, and an accelerator is not engaged, and (b) controlling a vehicle motor to transition from a first mode to a second mode in response to (a). In the first mode, the motor is controlled to output torque in response to the accelerator position, and in the second mode, the motor is controlled to output torque sufficient to preload the electric vehicle. The method also includes (c) detecting the brake is transitioning away from being engaged and the accelerator is not engaged, and (d) controlling the motor to operate in a third mode in response to (c). In the third mode the motor is controlled to output torque sufficient to maintain the electric vehicle stationary.

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Foster City, CA, United States of America

Tai-Sik Hwang