System for charging an energy store, and method for operating the charging system

• US 9,178,365 B2
• Filed: 12/29/2011
• Issued: 11/03/2015
• Est. Priority Date: 02/09/2011
• Status: Active Grant

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Feuerstack, Peter, Weissenborn, Erik, Kessler, Martin
• Primary Examiner(s): GLASS, ERICK DAVID
• Application Number:
  US13/984,560
• Publication Number:
  US 20130307445A1
• Time in Patent Office: 1,405 Days
• Field of Search: 318/139
• US Class Current: 1/1
• CPC Class Codes: B60L 50/51 characterised by AC-motors
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 2207/40 adapted for charging from various sources, e.g. AC, DC or multivoltage
• CPC Class Codes: H02J 2300/28 The renewable source being wind energy wind motors F03D
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence
• CPC Class Codes: H02J 7/0014 Circuits for equalisation of charge between batteries
• CPC Class Codes: H02J 7/0024 Parallel/serial switching of connection of batteries to charge or load circuit
• CPC Class Codes: H02J 7/0025 Sequential battery discharge in systems with a plurality of batteries
• CPC Class Codes: H02J 7/1492 by means of controlling devices between the generator output and the battery
• CPC Class Codes: Y02E 10/76 Power conversion electric or electronic aspects
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles

Abstract

The invention relates to a system for charging at least one energy storing cell (5) in a controllable energy store (2) that is used to control and supply electric energy to an n-phase electric machine (1), wherein n>1. The controllable energy store (2) has n parallel energy supply branches (3-1, 3-2, 3-3), each of which has at least two serially connected energy storing modules (4), each said energy storing module comprising at least one electric energy storing cell (5) with a corresponding controllable coupling unit (6). The energy supply branches (3-1, 3-2, 3-3) can be connected to a reference bus (T-), and each energy supply branch can be connected to a phase (U, V, W) of the electric machine (1). The coupling units (6) bridge the respective corresponding energy storing cells (5) or connect same into the respective energy supply branch (3-1, 3-2; 3-3) dependent on control signals. The aim of the invention is to allow at least one energy storing cell (5) to be charged. This is achieved in that an external energy source (10) can be connected to a neutral point (S) of the electric machine (1) and to the reference bus (T-).

Claims

1. A system for charging at least one energy storing cell in a controllable energy store that is used to control and supply electric energy to an n-phase electric machine, wherein n≧

1,

the controllable energy store having n parallel energy supply branches, which

have respectively at least two serially connected energy storing modules,

each said energy storing module comprising at least one electric energy storing cell with a corresponding controllable coupling unit,

can be connected on the one hand to a reference bus and

can be connected on the other hand to a phase of the electric machine,

the coupling units bridging the respective corresponding energy storing cells or connecting said respective corresponding energy storing cells into the respective energy supply branch dependent on control signals,

an external energy source being able to be connected on the one hand to the star point (S) of the electrical machine and on the other hand to the reference bus,

wherein the external energy source is embodied as a voltage source, the voltage value of which lies below the voltages of the energy supply branches, and the coupling units can be operated in combination with motor inductances of the electric machine as boost converters, and

wherein an additional charging inductance is connected between the energy source and the star point of the electric machine.

2. The system according to claim 1, wherein the energy source is embodied as a DC voltage source.

3. The system according to claim 1, wherein the energy source is embodied as an AC voltage source and the coupling units as full bridges.

4. A system for charging at least one energy storing cell in a controllable energy store that is used to control and supply electric energy to an n-phase electric machine, wherein n≧

1,

the controllable energy store having n parallel energy supply branches, which

have respectively at least two serially connected energy storing modules,

each said energy storing module comprising at least one electric energy storing cell with a corresponding controllable coupling unit,

can be connected on the one hand to a reference bus and

can be connected on the other hand to a phase of the electric machine,

the coupling units bridging the respective corresponding energy storing cells or connecting said respective corresponding energy storing cells into the respective energy supply branch dependent on control signals,

an external energy source being able to be connected on the one hand to the star point (S) of the electrical machine and on the other hand to the reference bus,

wherein the controllable energy store has at least two parallel energy supply sources, a distribution of a current fed by the energy source can be adjusted to the energy supply branches via the voltages of said energy supply branches and the voltages of said energy supply branches are determined by the number of energy storing cells connected into the respective energy supply branch.

5. The system according to claim 4, wherein the external energy source is embodied as a current source.

6. The system according to claim 4, wherein the external energy source is embodied as a voltage source, the voltage value of which lies below the voltages of the energy supply branches, and the coupling units can be operated in combination with motor inductances of the electric machine as boost converters.

7. The system according to claim 6, wherein an additional charging inductance is connected between the energy source and the star point of the electric machine.

8. The system according to claim 4, wherein the energy source is embodied as a DC current source or as a DC voltage source.

9. The system according to claim 4, wherein the energy source is embodied as an AC current source or as an AC voltage source and the coupling units as full bridges.

10. A method for operating a charging system according to claim 4, the method comprising simultaneously charging energy storing cells in all of the energy supply branches.