Protection of a power supply including a plurality of batteries in parallel against an external short circuit

Patent metadata

Field	Value
Publication number	US-9948086-B2
Application number	US-201414889020-A
Country	US
Kind code	B2
Filing date	Apr 24, 2014
Priority date	May 7, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

An electrical installation includes a circuit-breaker having a breaking capacity PdC and a tripping current Is, an ammeter measuring the current, and a DC voltage source comprising batteries connected in parallel and connected in series with the circuit-breaker. The sum of the short-circuit currents of the batteries connected in parallel is higher than the breaking capacity PdC of the circuit-breaker. A plurality of the batteries each includes a respective switch capable of opening a connection between the battery of the same and the circuit-breaker. The electrical installation also includes a control circuit to detect that the current passing through the circuit-breaker is higher than the tripping current Is and to control the opening of a plurality of the switches in order to apply, through the circuit-breaker, a current higher than the tripping current Is of the same and lower than the breaking capacity PdC of the same.

First claim

The invention claimed is:

1. An electrical installation, comprising:
a circuit-breaker with a breaking capacity PdC and a tripping current Is;
an ammeter for measurement of the current flowing in the circuit-breaker; and
a DC voltage source comprising electrochemical accumulator batteries connected in parallel, whereby said voltage source is connected in series with the circuit-breaker,
wherein a sum of the short-circuit currents of the batteries connected in parallel is greater than the breaking capacity PdC of the circuit-breaker, whereby a plurality of said batteries comprise a respective switch which is capable of opening a connection between their battery and the circuit-breaker, and
wherein the electrical installation comprises a control circuit which is configured for the detection of a current flowing in the circuit-breaker which exceeds the tripping current Is, and is configured to control the opening of a plurality of said switches in order to ensure that the current flowing in the circuit-breaker exceeds the tripping current Is thereof and is lower than the breaking capacity PdC thereof upon said detection.

2. The electrical installation as claimed in claim 1 , wherein each of said batteries connected in parallel comprises one of said respective switches.

3. The electrical installation as claimed in claim 1 , wherein fewer than half of said batteries connected in parallel comprise one of said respective switches.

4. The electrical installation as claimed in claim 1 , wherein one of said batteries comprises an ammeter for the measurement of the current flowing in its respective switch, and comprises a control circuit for the control of the opening of the switch in order to regulate the current flowing in the switch to a level which is lower than the maximum short-circuit current.

5. The electrical installation as claimed in claim 1 , wherein the tripping current Is of the circuit-breaker is a tripping current for a short-circuit of duration less than 100 ms.

6. The electrical installation as claimed in claim 1 , further comprising at least 10 of the batteries connected in parallel.

7. The electrical installation as claimed in claim 1 , further comprising a number n of the batteries connected in parallel, wherein each of said batteries exhibits a short-circuit current Icc i , and wherein the breaking capacity PdC of the circuit-breaker is at least three times lower than the sum

∑

i
=
1

n

⁢

Icc
i

of the short-circuit currents of said batteries.

8. The electrical installation as claimed in claim 1 , wherein each of said switches incorporates a transistor in which the current delivered by its respective battery flows.

9. The electrical installation as claimed in claim 1 , wherein each of said batteries comprises a first combination of electrochemical accumulators connected in series, and a second combination of electrochemical accumulators connected in series, and wherein the electrical installation also comprises a DC/DC converter an output voltage of which is connected in series with said first combination of electrochemical accumulators, wherein the second combination of electrochemical accumulators applies a potential difference to an input interface of the converter.

10. The electrical installation as claimed in claim 9 , wherein said converter constitutes a voltage-reducing structure during the discharging of said second combination of electrochemical accumulators.

11. The electrical installation as claimed in claim 10 , wherein:
said voltage-reducing structure incorporates a stepdown switching regulator comprising two controlled switches connected in series and to the terminals of which the potential difference of the second combination of electrochemical accumulators is applied;
said converter incorporates:
an inductance connected between a first terminal of the respective switch of the battery and a first output terminal of the DC voltage source, and
a free-wheeling diode connected between a second output terminal of the DC voltage source and said first terminal of said respective switch; and

the second terminal of the respective switch is connected to a connection node between the controlled switches of the reducer.

12. The electrical installation as claimed in claim 11 , wherein said respective switches comprise at least one component for the blocking of the current flowing from said first terminal to said connection node between said two controlled switches.

13. The electrical installation as claimed claim 1 , wherein the circuit-breaker has a breaking capacity at least equal to 5 kA.

Assignees

• Commissariat Energie Atomique

Inventors

• Chatroux Daniel
• Carcouet Sebastien
• Dauchy Julien

Classifications

• H01M50/583

  in response to current, e.g. fuses · CPC title

• H01M2/34

  Electricity · mapped topic

• H02H3/087 Primary

  for DC applications · CPC title

• B60L2200/18

  Buses · CPC title

• B60L2200/30

  Trolleys · CPC title