| 主权项 |
1. A method for braking an electric drive motor having:
a rotor; a stator defining a periphery; a plurality of field coils; said stator being configured to carry said field coils over said periphery such that said field coils are in spaced relationship to each other; said field coils having electrical phase connections (U, V, W) for at least three motor phases; a voltage supply (UV); a plurality of electronic switches (H1, H2, H3, L1, L2, L3); said electrical phase connections being connected to said voltage supply via corresponding ones of said electronic switches (H1, H2, H3, L1, L2, L3) to generate an electromagnetic field to drive said rotor; a control unit configured to actuate said electronic switches (H1, H2, H3, L1, L2, L3) and to close said switches in dependence on the rotational position of said rotor; said control unit being further configured to generate a braking current (IB) to brake said rotor by short-circuiting said electrical phase connections (U, V, W); the method comprising the steps of: switching a phase short circuit between each two of said phase connections (U-V, V-W, W-U) of said field coils via said electronic switches (H1, H2, H3, L1, L2, L3) in a predetermined temporal sequence while a further one of said phase connections (W, U, V) remains open; and, selecting phase connections (U-V, V-W, W-U) short circuited by said electronic switches (H1, H2, H3, L1, L2, L3) each in correspondence to the rotational position of the rotor such that the field coil is short circuited in which the induction voltage (UI) generated by the magnetic field of the rotating rotor passes through its maximum. |
