Mining Vehicle
AssigneeSandvik Mining and Construction Oy
InventorsMikko Kouvo, Samuli Kouhia
Life of this patent
Estimating the term…
Abstract
A mining vehicle and a method of operating a mining vehicle. The mining vehicle includes a three or more phase electric drive motor. A nominal power of the drive motor is determined on the basis of a certain drive speed and load, whereby the drive motor has a nominal torque at a certain rotating speed. The drive motor is connected to a traction wheel of the mining vehicle using a fixed gear ratio. The rotation speed of the drive motor is controlled by using a motor controller. That drive motor is operated in a delta connection on the certain drive speed and when necessary the torque of the drive motor at a drive speed lower than the certain drive speed is increased by operating the drive motor in a star connection and simultaneously temporarily overloading the drive motor.
Claims10
A method of operating a mining vehicle, the mining vehicle having a three or more phase electric drive motor which has one or more separated windings per phase, the method comprising the steps of:
- determining a nominal power of the drive motor on the basis of a given drive speed and load, whereby the drive motor has a nominal torque at a given rotating speed;
- connecting the drive motor to a traction wheel using a fixed gear ratio;
- controlling the rotation speed of the drive motor by using a motor controller;
- and
- operating the drive motor in a delta connection at the given drive speed and when necessary, increasing the torque of the drive motor at a drive speed lower than said given drive speed by operating the drive motor in a star connection at the drive speed lower than said given drive speed and simultaneously temporarily overloading the drive motor, without increasing the amperage of the motor controller.
A mining vehicle, comprising:
- a three or more phase electric drive motor having a nominal power and a nominal torque;
- a connection between the drive motor and a traction wheel the connection having a fixed gear ratio;
- a motor controller for controlling a rotation speed of the drive motor;
- and
- a control unit arranged to operate the drive motor in a delta connection at a given drive speed and to operate the drive motor in a star connection at a speed lower than said given drive speed and simultaneously to overload temporarily the drive motor for increasing the torque of the drive motor at the drive speed lower than said given drive speed, as per need.
A mining vehicle as claimed in claim, wherein the motor controller is an inverter.
Dependencies are inferred from the claim text.