DESCRIPTION

Scope of the invention

The present invention relates to the field of systems for managing the recharge of electric or hybrid vehicles.

Background art

The technical standards IEC 62196-1, 62196-2 and 61851 are the reference standards in the field of standardization of the recharge specifications of electric or hybrid vehicles in order to ensure the interoperability between vehicles and recharge stations.

The standard IEC 61851-1 specifies four modes of interconnection of an electric vehicle with an external power grid .

Mode 3 is the reference one in Europe for public recharge stations. It provides for

slow or fast recharge using a dedicated recharge station (column) provided with its own control unit, the cable not to be permanently attached to either the vehicle or the socket

control and protection functions to be permanently installed in the recharge station through the above control unit,

an intercommunication to be established between the vehicle and the control unit of the recharge station through the cable.

For a mode 3 recharge to be possible, the connector must have at least 7 pins, of which 3 phase 3F, neutral N, earth PE, a proximity pin and a control pin, also called pilot pin.

The proximity pin is connected via a resistance Rc of predefined value to the earth conductor.

For convenience, such a resistance is indicated as proximity resistance.

An electronic unit (VMU, from the expression Vehicle Management Unit) is installed on board the vehicle, which electronic unit is capable of measuring the value of such a resistance, recognizing the cable performance in terms of capacity of the cable itself to transfer electric current. The standard IEC 61851-1 specifies that the 13A current corresponds to Rc = 1.5 kOhm, 2 OA -> Rc = 680 Ohm, 32A -> Rc = 220 Ohm and 70A corresponds to Rc = 100 Ohm.

The control pin, on the other hand, allows the communication of a dedicated recharge control unit (RCU, the acronym of the expression Recharge Control Unit) , installed on board the vehicle and capable of communicating with the control unit installed on board the recharge station.

The electronic control units RCU and VMU communicate with each other through the vehicle network CAN.

Unit VMU, among other things, manages the recognition of the cable and the interlock of the sockets with the respective plugs, so that the cable may not be disconnected until the recharge is not completed or aborted by the vehicle.

Unit RCU, through the control pin, verifies the correct connection to the earth system of the recharge station, negotiates with the recharge station the maximum current that can be supplied by the same and informs unit VMU, which in turn controls the vehicle battery charger accordingly.

A vehicle designed for functioning in mode 3 must necessarily communicate with a recharge station implementing the recharge mode 3.

This implies that the same vehicle, in order to be charged also in the private sector, needs to communicate with a suitable recharge station.

However, this entails a further management cost for the vehicle fleet, especially in case of fleets of tens or hundreds of vehicles. Summary of the invention

Therefore, the object of the present invention is to propose a system for managing the recharge of electric or hybrid vehicles complying with the above standards, but at the same time able to allow the recharge of vehicle batteries, also in the private sector, without the installation of a specific recharge station.

The idea at the basis of the present invention is to enable unit VMU to recharge the vehicle batteries, irrespective of the execution of the functions of unit RCU.

This is made possible on the basis of the reading of the value of the above proximity resistance, through said proximity pin.

In other words, if resistance Rc has a new predefined value compared to those already predetermined by the standards IEC, unit VMU can proceed to the activation of the vehicle battery charger, even if unit RCU is deactivated, or even if unit RCU, following an attempt of communication with a corresponding electronic unit, has reported a negative result, or a null value of power supplied by the recharge station .

Therefore, thanks to the present invention, it is possible to recharge a vehicle even in the absence of a proper recharge station, provided that the connection cable to the power grid has a new further predefined value of proximity resistance Rc .

Moreover, the present solution solves the problem of supplying the electricity needed for keeping in activation temperature some types of vehicle batteries, which would otherwise become out of power or, after a certain period of time, would disable completely, making it impossible to use the vehicle in a short time.

It is worth noting that the current division of the functions between unit VMU and RCU is only by way of example, therefore, assuming that a single control unit or multiple control units execute the functions described above in compliance with the standards IEC, the concept of neglecting the result of processes or inhibiting the execution of some processes is equivalent to neglecting the result of the operations carried out by the RCU or is equivalent to its deactivation, as described above. Therefore, hereafter, rather than referring to specific devices, reference will be made to logical blocks VMU and RCU, implementable in one or more vehicle processing units.

Therefore, such a new predefined resistance value not only enables a functioning of the VMU different from what standardized by the standards IEC, but at the same time it continues to indicate the cable performance in terms of capacity of the cable itself to transfer electricity.

For example, a value of 3 kOhm could indicate the connection to a private power grid of the three-phase type, without any recharge station, with maximum deliverable current of 32A. Continuing with the example, a value of 6 kOhm could indicate the connection to a private power grid of the single-phase type with maximum deliverable current of 16A and a value of 9 kOhm could indicate the connection to a private power grid of the single-phase type with maximum deliverable current of 10A.

The resistance values indicated herein are only by way of example .

The object of the present invention is a system for managing the recharge of an electric or hybrid vehicle according to claim 1.

Another object of the present invention is a method of functioning of a system for managing the recharge of an electric or hybrid vehicle.

Another object of the present invention is a recharge cable having a proximity resistance different from the above values regulated by the above standard IEC 61851-1.

A further object of the present invention is a vehicle comprising the above recharge management system.

The claims describe preferred embodiments of the invention and form an integral part of the present description .

Brief description of the figures

Further objects and advantages of the present invention will become apparent from the following detailed description of an exemplary embodiment thereof (and of variants thereof) and from the accompanying drawings, which are merely

illustrative and non limiting, in which:

figure 1 shows an interconnection diagram of an electric or hybrid vehicle to a public recharge station according to the known art;

figure 2 schematically shows the interaction between vehicle logical functions and the pins of a type 2 or 3 plug

(i.e. complying with the standard IEC 61851-2) according to the present invention,

figure 3 shows a block diagram relating to the above logical functions modified according to the present invention .

The same reference numerals and letters in the figures identify the same elements or components.

Detailed description of exemplary embodiments

Figure 1 of the prior art shows a recharge station RS to which a cable Ca is connected, having a first end provided with plug PS to mechanically and electrically connect to the recharge station RS and a second end provided with plug PV to mechanically and electrically connect to an electric or hybrid vehicle HEV to be subjected to recharge of the batteries .

Figure 2 shows the logical block RCU, which as described above has the task of communicating with a respective processing unit RSU installed on board a public recharge station according to the functioning mode 3.

On the other hand, the logical block VMA has the task of verifying the performance characteristics of the cable through the reading of the proximity resistance Re and of verifying the vehicle side plug/socket interlock during the recharge operations. Moreover, on the basis of a supply current value negotiated by the RCU, it controls the battery charger AC/DC on board the vehicle. The battery charger takes the power signals from one of pin 3F and from the neutral, if the power grid available is single-phase, or from all pins 3F and from the neutral if the power grid available is three- phase .

Communications between RCU, VMU and AC/DC are done via the vehicle network CAN.

According to the present invention, when the logical block VMA detects a proximity resistance value Rc different from those specified by the standard IEC 61851-1, the functioning of the logical block RCU is inhibited or, if its functioning is still enabled, the outcome of the related processing is ignored .

Figure 3 shows a method of functioning of the system for managing the recharge of an electric or hybrid vehicle according to the present invention.

In step 1, the cable connection to the vehicle takes place, in step 2, the proximity resistance value Rc is measured, in step 10, if such a value does not belong to the list of values predetermined by the standard IEC 61851-1, then (NO) next is step 5, that is to say, setting of a maximum value, for the battery charger, of a recharge current of the batteries as a function of only the cable characteristics. If, on the other hand, the proximity resistance value RC belongs to the list of values predetermined by the standard IEC 61851-1 then, in step 3, the logical block RCU is enabled,

in step 4, the logical block RCU asks the processing unit on board the recharge station to negotiate the maximum current deliverable by the station,

in step 5, the RCU transmits the maximum current value negotiated to the VMU and the VMU sets up the functioning of the battery charger according to such a negotiated value and to the performance characteristics of the cable.

It is clear that the current value set for the battery charger is the smaller between the cable capacity and the power deliverable by the recharge station.

An electric cable according to the present invention, therefore, has at a first end a single-phase or three-phase plug of the traditional five-pole type, i.e. with 3F + N + PE, while at a second end it is provided with a plug having 7 pins, as specified by the standards IEC 61851-2 of type 2 and/or 3, in which the pilot pin is insulated and the proximity pin is connected to the earth conductor PE by means of a proximity resistance Rc of predefined value, different from what predefined by the standard IEC 61851-1.

The present invention may be advantageously implemented by a computer program which comprises coding means for implementing one or more steps of the method, when this program is run on a computer. Therefore, it is understood that the scope of protection extends to said computer program and moreover to computer-readable means which comprise a recorded message, said computer-readable means comprising program coding means for implementing one or more steps of the method when said program is run on a computer.

Embodiment variants of the non limiting example described are possible without departing from the scope of protection of the present invention, comprising all the equivalent embodiments for a man skilled in the art.

From the above description, the man skilled in the art is able to implement the object of the invention without introducing any further construction details. The elements and the features shown in the different preferred embodiments may be combined without departing from the scope of protection of the present application. What described in the description of the prior art, unless specifically excluded in the detailed description, must be considered in combination with the features of the present invention, forming an integral part of the present invention.