The present invention relates to a supply system electrical energy including an onboard network of a submarine.
More particularly, the invention relates to such an electric power supply system which comprises means for storing electrical energy lithium batteries base.
These power supply systems also comprise means for distribution of the electrical energy to a user loads, these means of power distribution comprising means for cleavage and isolation of the connection limbs of loads user to the network, particularly where short-circuit thereof.

Traditionally, the means for storing electrical energy for such applications eg submarines were based on the use of lead batteries.

Network Protection The devices were then sized to cut short-circuit current example of this type of battery, these currents may for example be up to 50 kA.

But the current trend is to use lithium batteries and particularly Lithium / ion, as a means of storing electrical energy for the type of applications envisaged.

However, the current short-circuit such lithium / ion batteries are much higher than the short-circuit currents lead batteries.

It cites, for example, 300 kA values, ie values ​​six times higher than the short-circuit currents lead batteries.

This raises the question of how to cut or suspend such short circuit currents with previous design of network protection devices.

The Applicant has already proposed to reduce the current of short circuit in case of internal or external fault, by inserting into the power line of each branch in parallel constituting the storage system of electric energy, for example a current chopper.

The chopper then limits the output current of each branch to a value set in advance.

Thus, the current short circuit is limited to a value compatible with the characteristics of network protection devices which is connected to the battery.

However, the development of this type of chopper system is complicated by the need for coordination between different branches of choppers and knowledge of the downstream impedance chopper for proper operation of the solution.

Other solutions have been proposed for example in EP 1641066.

In it the battery is proposed to make each branch to limit the short circuit current.

The basic concept of this structure is then to limit short-circuit current does connecting a limited number of branches.

This document then provides a connection management system and disconnections branches and battery charge.

This system requires a discharging circuit and a charging circuit decoupled for example by diodes.

In addition it requires a complex management of the capacity of the different branches of the battery during charging and discharging.

This management requires knowing precisely the charge states of the branches to avoid excessive trade flows between branches when connecting and disconnecting them.

But accurate knowledge of the state of charge of a lithium battery is not simple.

Alternatively limitation and break short-circuit currents for lithium batteries of high capacity, especially for applications submarine, was also presented in 2013.

This system proposes to insert, in case of failure on the network, a resistor in the power line of the branches of the battery to reduce the current value by dissipating high heat energy.

A system of static switches, for example semiconductor, allows to divert the current in this resistor when overcurrent detected output branches of the battery.

This system requires a water cooling device and request a full study of the protection plan and selectivity of the grid for each type of submarines which it operates to set the value of the resistance that will limit the current short circuit to a value permitting the operation of electric network protection systems.

Such a solution is described for example in WO 2010/089338.

Thus these solutions are based on a limitation of the output current branch of the battery to ensure the network protection and selectivity of the event of default network, this limitation to ensure a current value provided by the battery compatible with the characteristics of network protection devices.

But we have seen that such systems are complex and complicated to or developed and implemented.

The purpose of the invention to solve these problems.

To this end the invention relates to an electric power supply system including an onboard network of a submarine of the type comprising means for storing electrical energy based on lithium and means for distributing the electric power to user loads, these distribution means comprising means for cutting and isolation of the connection limbs of the user loads especially in case of short-circuit thereof, characterized in that it comprises:

- means for monitoring the evolution of the output current means for storing electrical energy to detect the occurrence of a short circuit in the network,

- disconnecting means of the electrical energy storage means from the network in the event of such detection,

- means of connection to the network, means for generating a current short-circuit control, to trigger operation of the means of cleavage and isolation associated with the branch short-circuited in order to isolate the latter the rest of the network,

- means for disconnecting the current generator short-circuit of the network, and

- means of connection means for storing electrical energy to the rest of the network.

According to other features of the system according to the invention, taken alone or in combination:

- the current evolution monitoring means delivered by the means for storing electrical energy comprises means for analyzing the variation in this current over time to detect the occurrence of a short circuit that variation exceeds a predetermined threshold;

- the electrical energy storage means comprise several parallel branches which each comprise disconnecting means;

- the battery disconnection means comprise controlled semiconductor switching members;

- semiconductor switches driven bodies include MOSFETs;

- means of cleavage and isolation loads of connection limbs user include circuit breakers;

- the distribution means comprise at least one battery table, at least one main panel and at least one secondary switchboard of electric energy, connected between the energy storage means and the user loads;

- it further comprises means for measuring isolation from the rest of the network after disconnecting the energy storage means, to avoid these reconnect to the network storage means, upon detection of an insulation fault of the network .

The invention will be better understood from reading the following description given purely by way of example and with reference to the accompanying drawings, wherein:

- Figure 1 shows the general structure of part of a power system in electric power including an onboard network of a submarine, - Figures 2 to 7 illustrate the operation of such a system according to a first embodiment, and

- Figures 8 to 16 illustrate the operation of such a system according to a second embodiment.

It has in fact shown in Figure 1, a power system in electric power including an onboard network of a submarine.

The latter comprises means for storing electrical energy lithium battery base, designated by the general reference 1.

In fact, these energy storage means comprises a plurality of branches in parallel batteries, designated by the general reference 2, 3 and 4, for example in FIG 1.

Each of these branches is connected to an array of battery designated by the general reference 5, through means of connection / disconnection, respectively 6, 7 and 8.

As will be described in more detail below, these means of connection / disconnection switches comprise for example organs semi-

driver controlled, such as, for example MOSFET transistors, inserted in the branches.

Of course, other semiconductor switch devices may be envisaged.

The battery table 5 also comprises a switch designated by general reference 9.

This battery array 5 is connected to at least one main switchboard of electrical energy, one of which is designated for example by the general reference 10 in this Figure 1.

This main switchboard of electrical energy 10 also comprises for example several supply branches, each of which also comprises a circuit breaker.

And a branch is illustrated in this figure and includes a circuit breaker designated by the general reference 1 1 of this Figure.

This branch power is used to connect the main board 10 of electrical power distribution, with at least one secondary table of distribution of electricity, one of which is designated for example by the general reference 12 in this Figure.

This secondary distribution board electrical power supplies 12 of the connection limbs of user loads, such as the branch designated by the general reference 13 in this figure, through means of cleavage and isolation branch comprising also for example a circuit breaker, designated by the general reference 14.

A short-circuit generator, designated by the general reference 15, is connected to the array of battery 5, by means of connection means in the form of switch, designated by the general reference 16 in this Figure, controllable closure and the opening for connecting or disconnecting the generator 15 of table battery 5.

Such a feed structure is then relatively conventional in so far as the means for storing electrical energy comprises batteries branches lithium battery connected to a table, which is itself connected through a cascade of primary and secondary tables distribution to the connection limbs of user loads.

Each of these tables comprises cut-off means and isolated for example based circuit breakers, which are then sized according to their location in the feed cascade to cut the corresponding branch and isolate it from the rest of the network.

Unlike systems of the prior art, which proposed to limit the value of short circuit current output of the battery system, the system of the invention there is provided to disconnect the battery before it n ' reaches its maximum value of short-circuit current.

is then used for this purpose cut-off means comprising semiconductor bodies.

To illustrate the problem mentioned above concerning the value of the battery short-circuit current lithium, we can take as an example the case of a parallel connection of multiple battery packs for the applications of several hundred kilowatts / hour.

The short circuit current of the system can reach extremely high values.

For example if we consider fifty packs of batteries in parallel, each of which can provide 4 kA, this translates into a short-circuit current of the system of the order of 20 kA.

Conventionally, a fuse DC under current technology has a power outage that up to 100 kA and must be changed after melting, which in the applications mentioned, is not possible or at least n ' is not acceptable, for reasons of accessibility and fast availability of energy after a fault.

Similarly, a DC circuit breaker that can be reset it, also has a breaking capacity than the order of up to 100 kA according to current technologies.

Thus, these systems are not designed to be able to cut short circuit values ​​beyond this value.

This is why the invention proposes to act before the short-circuit current reaches its maximum value.

This limits the short-circuit current within acceptable values ​​by the one or more circuit breakers or fuses or as described, to ensure the opening of the circuit while remaining within the area in which the protector assembly is adapted to interrupt current.

Another aspect to be taken into account when dimensioning the protection of such a circuit, and in particular calibration of the circuit breakers is the selectivity of the different components of the whole chain or cascade of circuit breakers or fuses power distribution system.

For this, the short-circuit current must be controlled.

In particular, it should not be limited too low or risk seeing some breakers open too slowly, or even not to open at all, which would be dangerous for the protection of the general network and the different components of it in particular.

Do not the battery pack limits the short circuit current to a level such that it does not crack up downstream for electrical distribution protection in the network, otherwise the entire system will be fully default for any local fault.

For this purpose, in the power system according to the invention, means for monitoring the evolution of the output current means for storing electrical energy to detect the occurrence of a short circuit in the network.

In particular, the monitoring means analyzes the change in the current over time to detect a crossing of a threshold limit tripping characteristic of a short circuit fault for example.

These monitoring means are designated by the general reference 17 in Figure 1.

The current monitoring means are then used to trigger the operation of the various means and system and network protection devices, to ensure the overall protection of the network, the selectivity of the trigger and the handover of electrical power optimally what is important for this type of application.

Is illustrated in Figures 2-7, a first embodiment of such a system.

It is recognized in these Figures 2-7, the various elements that have already been described in reference to FIG 1.

Upon occurrence of a fault on one of the user load branches such as for example the arm 13, as illustrated in Figure 2, the means 17 for changing the output current monitoring means for storing electrical energy, detect the occurrence of this fault and in particular a short-circuit in the network.

This monitoring is done such an analysis of the current variation in time conventionally.

In response to this detection of the short circuit, the system triggers the disconnection of the means for storing electrical energy from the network, by opening the semiconductor switching members 6, 7 and 8, as is illustrated in Figure 3.

Once these semiconductor switching members open, the system connects to the network and more particularly in Table 5, the generating means of short-circuit 15, as shown in Figure 4, closing the connecting means 16.

As mentioned above, these generating means are adapted to cause a current short-circuit control, to trigger the operation of the breaking means and isolation associated with the faulted branch short-circuit, in order to isolate it from the rest of the network, as illustrated in Figure 5.

Indeed, the chain or cascade of network protection switches, are located at different levels thereof, is designed and calibrated to allow obtaining selectivity mentioned above, opening of the faulty branches as the branch 13.

This makes it possible to isolate the branch and the fault relative to the rest of the supply circuit.

Once the isolated defect, the system opens the means 16 for connecting the short-circuit generator to disconnect from the network.

The circuit breaker 14 of the default user load branch, for example 13 being open, it is then possible to reconnect the battery to the network to make available again the electric power, closing the semiconductor switching members 6, 7 and 8, as shown in Figure 7.

This will restore the power of the network except for the branch 13 in default.

It is understood that such a structure has a number of advantages.

Indeed, by monitoring the evolution of the current output of the means for storing electrical energy, and in particular, by analyzing the variation in this current over time to detect the occurrence of a short circuit, as soon as this variation exceeds a predetermined threshold, it is possible to anticipate operation of the means of security and network protection.

In response the system initially causes the disconnection of the battery.

And the generating means of short-circuit are connected to the network for triggering the circuit breaker of the faulted user load branch.

This isolates the fault of the rest of the network.

The short circuit is then disconnected generator of the network and it is possible to reconnect the battery to the network to make available electric power.

Figures 8 to 16, an alternative embodiment is illustrated of this system, which further incorporates means 20 for insulation measurement of the rest of the network after disconnecting means for storing electrical energy, to avoid dimensioning means 16 so that they can carry the current short-circuit generating means 15 to closing.

The general operation of this embodiment of the system according to the invention is very close to that which was described above.

Indeed, upon detection of the occurrence of a fault, Figure 8, the system disconnects the battery from the network, Figure 9.

Then, as illustrated in Figure 10, the system opens the circuit breaker 9 Battery Table 5, to allow, Figure 1 1, the means 20 for measuring the isolation from the rest of the network and determining whether it is possible or not to continue the progress of the fault isolation process as described.

If this is the case, in FIG 12, the short-circuit generator 15 is connected to the network by the means 16 and the circuit breaker 9 of the battery 5 panel is closed, Figure 13.

This makes it possible to cause the opening of the circuit breaker associated with the faulted branch as shown in Figure 14, to isolate it from the rest of the network.

Disconnection of the short-circuit current generator is illustrated in Figure

15 and the reconnection of the battery 16 in FIG.

It is therefore understandable that in the system according to the invention, means are used in semiconductor-based MOSFETs, for example, the output of each branch of the battery, whose functionality is opened rapidly for example in a time less than 100 microseconds, in the event of detection of an excessive rise of the current.

This makes it possible to disconnect the battery before it has established its nominal value of short circuit current.

A current generator short-circuit is then connected to the network.

Its function is to provide sufficient current short-circuit to remove the short-circuit by opening the protector assembly of the faulted branch.

Once the fault has been eliminated, the short circuit current is isolated from this network generator and the battery is reconnected to the network.

Different short-circuit current generators of technologies can be considered as for example electromechanical technology.

The connecting means of the current generator short-circuit can also be based technology of controlled semiconductor switches.
Of course, other embodiments still may be envisaged.

CLAIMS

1. - System of electric power supply including an onboard network of a submarine of the type comprising means (1) Battery-based electrical energy storage lithium and means (5, 10, 12) for distributing the electric power to user loads, these distribution means comprising means (9: 1 1: 14) to cut and isolation legs (13) loads the connecting particular user in case of short-circuit thereof, characterized in that it comprises:

- means (17) for monitoring changes of the output current means for storing electrical energy to detect the occurrence of a short circuit in the network,

- means (6, 7, 8) disconnection means for storing electric energy from the network in the event of such detection,

- means (16) for connection to the network, means (15) for generating a current short-circuit control, to trigger the operation of means (14) cut and isolation associated with the branch shorted circuit (13) to isolate it from the rest of the network,

- means (16) for disconnecting the current generator short-circuit (15) of the network, and

- means (6, 7, 8) of connection means for storing electrical energy to the rest of the network.

2. - A supply system according to claim 1, characterized in that the means (17) for monitoring the evolution of the current delivered by the storage means of electric energy includes means for analyzing the variation of this current over time to detect the occurrence of a short circuit when this variation exceeds a predetermined threshold.

3. Fuel system according to Claim 1 or 2, characterized in that the means (1) for storing electrical energy comprise a plurality of parallel branches (2, 3, 4) each comprise means for disconnecting (6 , 7, 8).

4. Fuel system according to any one of the preceding claims, characterized in that the disconnecting means (6, 7, 8) of the battery comprise controlled semiconductor switching members.

5. Fuel system according to Claim 4, characterized in that the semi-conductor switching members comprise driven MOSFET transistors.

6. Fuel system according to any one of the preceding claims, characterized in that the means of cleavage and isolation of the user loads the connecting branches include circuit breakers (14).

7. Fuel system according to any one of the preceding claims, characterized in that the distribution means comprise at least one battery panel (5), at least a main board (10) and at least one secondary table ( 12) for distributing electrical power, connected between the energy storage means and the user loads.

8. Fuel system according to any one of the preceding claims, characterized in that it further comprises means (20) for isolation measurement from the network after disconnecting means of energy storage, for avoid these reconnect to the network storage means, upon detection of an insulation fault in the network.