METHOD FOR MONITORING THE CHARGING MODE OF AN ENERGY STORE IN A VECHILE AND CHARGING SYSTEM FOR CHARGING AN ENERGY STORE IN A VECHILE

• US 20140049215A1
• Filed: 08/30/2011
• Published: 02/20/2014
• Est. Priority Date: 10/12/2010
• Status: Abandoned Application

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Fassnacht, Jochen
• Application Number:
  US13/879,091
• Publication Number:
  US 20140049215A1
• Time in Patent Office: Days
• US Class Current: 320/109
• CPC Class Codes: B60L 2220/54 Windings for different functions
• CPC Class Codes: B60L 3/0023 Detecting, eliminating, remedying or compensating for drive train abnormalities, e.g. failures within the drive train
• CPC Class Codes: B60L 53/24 Using the vehicle's propulsion converter for charging
• CPC Class Codes: H02J 2310/48 for electric vehicles [EV] or hybrid vehicles [HEV]
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0047 with monitoring or indicating devices or circuits
• CPC Class Codes: H02J 7/1423 with multiple batteries
• CPC Class Codes: H02J 7/143 with multiple generators
• CPC Class Codes: H02M 1/007 Plural converter units in cascade push-pull DC/DC converters with pre-regulator H02M3/3374; DC-AC converters following a DC-DC stage including a high frequency transformer H02M7/4807; DC-AC converters following a DC-DC conversion stage generating periodically varying voltages H02M7/4826
• CPC Class Codes: H02M 7/217 using semiconductor devices only
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors
• CPC Class Codes: Y02T 10/92 Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y02T 90/12 Electric charging stations
• CPC Class Codes: Y02T 90/14 Plug-in electric vehicles

Abstract

In a method for monitoring the charging mode of an energy store in a vehicle which is drivable via an electric machine, the energy store is connected in the charging mode to an external energy supply system via a charging circuit which includes a unit operated as the boost converter, a controllable rectifier having upstream filter capacitors, and a system filter. A DC link capacitor is switched in parallel to the energy store. During the charging mode, at least one current and/or one voltage is monitored at the input, at the output, and/or within the charging circuit, and/or a function of a control unit of the rectifier and/or of the unit operated as the boost converter is monitored. If malfunction is detected, the charging circuit is switched into a free-running mode.

Claims

1-11. -11. (canceled)

12. A method for monitoring a charging mode operation of an energy store in a vehicle which is drivable via a three-phase electric machine, wherein the electric machine is connected to the energy store via a vehicle electrical system and is supplied with electrical power from the energy store during a driving mode, and wherein during the charging mode the energy store is connected to an external public power grid, via a charging circuit which includes a unit operated as a boost converter, and a controllable rectifier having upstream filter capacitors and a system filter, and wherein a DC link capacitor is switched in parallel to the energy store, the method comprising:

monitoring, during the charging mode, at least one of (i) a current at least one of at an input, at an output, and within the charging circuit, (ii) a voltage at least one of at the input, at the output, and within the charging circuit, (iii) a function of a control unit of the rectifier, and (iv) a function of a control unit of the unit operated as the boost converter; and

switching the charging circuit into a free-running mode, wherein in the free-running mode one branch of the controllable rectifier and all circuit elements controllable in a boost converter mode of the unit operated as the boost converter are connected through, and wherein the switching into the free-running mode occurs if at least one of the following conditions is satisfied;

the monitored current exceeds a predefined current threshold value;

the monitored voltage exceeds a predefined voltage threshold value;

a malfunction of the control unit of the rectifier is detected; and

a malfunction of the control unit of the unit operated as the boost converter is detected.

13. The method as recited in claim 12, wherein during the charging mode:

at least one of the following quantities is monitored;

a voltage at the DC link capacitor, a charging current of the energy store, and voltages at the filter capacitors; and

the charging circuit is switched into the free-running mode if one of the following conditions is satisfied;

the voltage at the DC link capacitor exceeds a predefined DC link capacitor voltage threshold value, the charging current of the energy store exceeds a predefined charging current threshold value, or at least one of the voltages at the filter capacitors exceeds a predefined filter voltage threshold value.

14. The method as recited in claim 13, wherein the electric machine is controlled via a pulse-controlled inverter in the driving mode, and wherein the inverter is operated as the boost converter in the charging mode.

15. The method as recited in claim 14, wherein inductances of the boost converter are formed at least partially by stator windings of the electric machine.

16. The method as recited in claim 14, wherein in the free-running mode of the charging circuit, all low-side switches of the inverter are connected through.

17. A charging system for charging an energy store in a vehicle, comprising:

a three-phase electric machine for driving the vehicle, wherein the energy store supplies the electric machine with energy during a driving mode;

a vehicle electrical system via which the electric machine and the energy store are electrically connected;

a DC link capacitor which is switched in parallel to the energy store;

a charging circuit which includes a unit operated as a boost converter, and a controllable rectifier having upstream filter capacitors and a system filter, wherein during a charging mode, the energy store is connected to an external public power grid via the charging circuit;

at least one monitoring unit which monitors at least one of (i) a current at least one of at an input, at an output, and within the charging circuit, (ii) a voltage at least one of at the input, at the output, and within the charging circuit, (iii) a function of a control unit of the rectifier, and (iv) a function of a control unit of the unit operated as the boost converter; and

an evaluation unit which selectively switches the charging circuit into a free-running mode, wherein in the free-running mode one branch of the controllable rectifier and all circuit elements controllable in a boost converter mode of the unit operated as the boost converter are connected through, and wherein the switching into the free-running mode occurs if at least one of the following conditions is satisfied;

the monitored current exceeds a predefined current threshold value;

the monitored voltage exceeds a predefined voltage threshold value;

a malfunction of the control unit of the rectifier is detected; and

a malfunction of the control unit of the unit operated as the boost converter is detected.

18. The charging system as recited in claim 17, wherein:

a first monitoring unit monitors a voltage at the DC link capacitor;

a second monitoring unit monitors a charging current of the energy store;

a third monitoring unit monitors voltages at the filter capacitors;

a fourth monitoring unit monitors at least one of the function of the control unit of the rectifier and the function of the unit operated as the boost converter;

a fifth monitoring unit monitors at least one of the current at the input and the current within the charging circuit; and

the evaluation unit switches the charging circuit into the free-running mode if one of the following conditions is satisfied;

the voltage at the DC link capacitor exceeds a predefined DC link capacitor voltage threshold value, the charging current of the energy store exceeds a predefined charging current threshold value, at least one of the voltages at the filter capacitors exceeds a predefined filter voltage threshold value, a malfunction of the control unit of the rectifier is detected, a malfunction of the control unit of the unit operated as the boost converter is detected, a current at the input exceeds a predefined input current threshold value, or a current within the charging circuit exceeds a predefined charging circuit current threshold value.

19. The charging system as recited in claim 17, wherein the electric machine is controlled via a pulse-controlled inverter in the driving mode, and wherein the inverter is operated as the boost converter in the charging mode.

20. The charging system as recited in claim 19, wherein inductances of the boost converter are formed at least partially by stator windings of the electric machine.

21. The charging system as recited in claim 18, wherein the fourth monitoring unit is implemented with the aid of a watchdog component.

22. The charging system as recited in claim 19, wherein the rectifier includes a freewheeling diode which is switched in parallel to the rectifier branches.