Electrical drive system and energy storage apparatus therefor

Patent metadata

Field	Value
Publication number	US-9735724-B2
Application number	US-201414898097-A
Country	US
Kind code	B2
Filing date	May 13, 2014
Priority date	Jun 11, 2013
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

A drive system may have at least one electric motor which can be fed via power electronics which can be connected via a DC circuit to a voltage source and an energy storage apparatus for buffering energy fed back from the electric motor. An energy storage apparatus for such a drive system may include at least one electrical storage block, a bidirectional DC/DC converter for connecting the named DC voltage circuit to the internal voltage circuit of the storage block and a control unit for controlling the DC/DC converter. The control unit may include output and feed control means for controlling the DC/DC converter. The DC/DC converter, the storage block and the control unit may be combined into an energy storage unit having a common housing in which the named components are received and at whose outer side two connections are provided for connecting to the DC voltage circuit.

First claim

The invention claimed is:

1. An energy storage apparatus for connecting to a DC voltage circuit of power electronics of a drive system, comprising at least one electrical storage block, a DC/DC converter for the connection of the DC voltage circuit to an internal voltage circuit of the storage block and a control apparatus for controlling the DC/DC converter, wherein the DC/DC converter is bidirectional,
wherein the control apparatus has output and feed control means for controlling the DC/DC converter both for the outputting of current from the storage block to the DC voltage circuit and for the feeding of current from the DC voltage circuit into the storage block, and
wherein the storage block, the DC/DC converter and the control apparatus are combined to form an energy storage unit having a common housing into which the storage block, the DC/DC converter, and the control apparatus are received and to whose outer side two power connections are provided for connection to the DC voltage circuit of the power electronics.

2. The energy storage apparatus in accordance with claim 1 , wherein the storage block comprises at least one dual-layer capacitor, for energy storage.

3. The energy storage apparatus in accordance with claim 1 , wherein the storage block and/or the DC/DC converter and/or the control apparatus are linked in the housing to an internal cooling circuit which has coolant connections at the housing for connection to an external cooling circuit.

4. The energy storage apparatus in accordance with claim 3 , wherein the internal and/or external cooling circuit is controllable by the control apparatus in dependence on a temperature of an electric component in the housing and/or on an environmental temperature and/or on an inner housing temperature.

5. The energy storage apparatus in accordance with claim 3 , wherein the coolant connections are configured as pluggable.

6. The energy storage apparatus in accordance with claim 1 , wherein the housing is configured as divisible and comprises a plurality of housing parts which can be put together to form the housing, and wherein different electric components of the energy storage unit, which are connectable to one another by conductive connection means, are accommodated in different housing parts of the plurality of housing parts.

7. The energy storage apparatus in accordance with claim 6 , wherein the conductive connection means comprise plug-in contacts, which automatically come into contact on the putting together of the housing parts, and which are provided at interfaces of the housing parts.

8. The energy storage apparatus in accordance with claim 1 , wherein a warning signal device is provided for outputting a warning signal when the storage block is still charged with energy and/or a disconnect switch is provided for disconnecting the storage block and/or for deenergizing the power connections at the housing.

9. The energy storage apparatus in accordance with claim 1 , wherein a discharge circuit is provided for converting energy stored in the storage block into heat, the discharge circuit controllable by a control command from outside of the energy storage apparatus.

10. The energy storage apparatus in accordance with claim 1 , wherein the control apparatus comprises control means for determining an energy index and for providing and/or transferring the energy index to a higher-ranking control, with the named energy index representing the energy available in the storage block.

11. The energy storage apparatus in accordance with claim 1 , wherein the control apparatus comprises control and/or regulation means for the DC/DC converter which, in response to a control signal from outside, converts definable power values for charging and/or discharging of the storage block by desired value defaults for regulation of the DC/DC converter.

12. The energy storage apparatus in accordance with claim 1 , wherein the control apparatus comprises power control means for regulating or controlling and/or limiting maximum transferable powers and/or comprises voltage regulation and/or control means for regulating or controlling an output voltage of the energy storage unit.

13. The energy storage apparatus in accordance with claim 1 , wherein the control apparatus is configured such that it can be supplied with configurable parameters from the outside and carries out a characteristic-controlled mode of operation on the basis of the configurable parameters from the outside.

14. The energy storage apparatus in accordance with claim 1 , further comprising a plurality of energy storage units which each have a storage block, a DC/DC converter and a control apparatus accommodated in a housing, the energy storage units connected to one another in a parallel connection.

15. The energy storage apparatus in accordance with claim 14 , wherein the plurality of energy storage units are directly connected to one another by external power connections in each case plus to plus and minus to minus.

16. The energy storage apparatus in accordance with claim 14 , wherein the control apparatus of the energy storage units connected in parallel are connected to one another, preferably via a bus system, and support the parallel connection such that all the storage blocks are set and/or controlled to an at least approximately uniform energy amount.

17. The energy storage apparatus in accordance with claim 14 , wherein the control apparatus of one energy storage unit of the plurality of energy storage units is defined as a master unit and the control apparatus of the other energy storage units of the plurality of energy storage units are defined as slave units which are controllable by the master unit.

18. An apparatus, comprising:
a drive system having at least one electric motor which is fed via power electronics, the power electronics connected via a DC voltage circuit to a voltage source, the drive system further comprising at least one energy storage apparatus for a buffering of energy fed back from the electric motor, the energy storage apparatus comprising at least one electrical storage block, a DC/DC converter for the connection of the DC voltage circuit to an internal voltage circuit of the storage block and a control apparatus for controlling the DC/DC converter, wherein the DC/DC converter is bidirectional
wherein a maximum voltage of the at least one storage block of the energy storage apparatus is kept lower than a minimum voltage of the DC voltage circuit.

19. The apparatus in accordance with claim 18 , wherein both feeding of fed back energy of the electric motor into the energy storage apparatus and outputting of buffered energy from the energy storage apparatus to the DC voltage circuit takes place via the DC/DC converter of the energy storage apparatus.

20. The apparatus in accordance with claim 18 , wherein the apparatus is a container bridge crane.

21. The apparatus in accordance with claim 18 , wherein the apparatus is a concrete mixer vehicle.

Assignees

• Liebherr Components Biberach Gmbh

Inventors

• Schuster Wolfgang
• Fenker Oliver
• Welser Sven

Classifications

• H02P27/04 Primary

  using variable-frequency supply voltage, e.g. inverter or converter supply voltage · CPC title

• H02P27/06

  using DC to AC converters or inverters (H02P27/05 takes precedence) · CPC title

• B60K6/28

  characterised by the electric energy storing means, e.g. batteries or capacitors · CPC title

• B60L11/1805

  Operations & Transport · mapped topic

• H02M5/458 Primary

  using semiconductor devices only · CPC title