SYSTEM FOR CHARGING AN ENERGY STORE, AND METHOD FOR OPERATING THE CHARGING SYSTEM

摘要

The invention relates to a system for charging at least one power cell (5) in a controllable energy store (2) used for controlling and supplying electric power to an n-phase electric machine, where n = 1. The controllable energy store (2) has n parallel power supply branches (3-1, 3-2, 3-3), each of which includes at least two serially connected energy storage modules (4). Each energy storage module comprises at least one electric power cell (5) having an associated controllable coupling unit (6) and is connected to a reference bus (T-) and to one respective phase (U, V, W) of the electric machine (1). The coupling units (6) disconnect the respective power supply branch (3-1, 3-2, 3-3), bridge the associated power cells (5), or connect the associated power cells (5) to the respective power supply branch (3-1, 3-2, 3-3) in accordance with control signals. In order to allow at least one power cell (5) to be charged, at least two phases (U, V) of the electric machine (1) can be connected to a negative terminal of a charging device (10) by means of at least one respective freewheeling diode (9-U, 9-V). The reference bus (T-) can also be connected to the negative terminal of the charging device (10). Each power supply branch (3-1, 3-2) connected to the phases (U, V) that can be connected to the negative terminal of the charging device (10) has a contact point (11-1, 11-2) which is arranged between two energy storage modules (4) and can be connected to a positive terminal of the charging device (10) by means of at least one freewheeling diode (12-1, 12-2).