ELECTROMECHANICAL DRIVE FOR A WORKING MACHINE

摘要

An electromechanical drive comprises an electrical machine (101a), an electrical power converter (103) for converting voltage of an external electrical system to voltage suitable for the electrical machine, and a gearbox (111a) for mechanically connecting the electrical machine to an actuator (112a) and capable of providing selectable transmission ratios between the electrical machine and the actuator. The electrical power converter comprises a controller for selecting one of the selectable transmission ratios at least partly on the basis of a) first data related to actual and/or desired torque-speed operating point of the actuator and b) second data related to functional properties of at least the electrical machine. Thus, the transmission ratio can be selected at least partly from the viewpoint of the electrical machine taking into account for example the most advantageous speed range and/or torque range of the electrical machine.

主权项

1. An electromechanical drive comprising:
an electrical machine, a gearbox having a first shaft connected to the electrical machine and a second shaft for driving an actuator, the gearbox being capable of providing selectable transmission ratios each being a ratio of a rotational speed of the first shaft to a rotational speed of the second shaft, and an electrical power converter for converting voltage of an external electrical system into voltage suitable for the electrical machine,wherein the electrical power converter comprises:
a controller for selecting one of the selectable transmission ratios at least partly on the basis of a) first data related to a torque-speed operating point of the second shaft when driving the actuator and b) second data related to functional properties of at least the electrical machine, and a signal output for delivering, to the gearbox, a control signal so as to set the gearbox to operate at the selected one of the selectable transmission ratios.