Plug-in hybrid motor vehicle equipped with a powertrain, controlled as a plug-in hybrid vehicle or as a hybrid vehicle.

Abstract

Plug-in hybrid motor vehicle equipped with a powertrain comprising at least one battery (4) and at least one electric motor (3), the powertrain comprising an electronic control unit for battery management (4) and a main electronic control unit comprising an interface (6) between the main electronic control unit and the electronic control unit for battery management, the interface (6) modifying information communicated by the electronic control unit for battery management to the main electronic control unit as to the usable state of charge of the battery (4), the energy acceptable by the battery (4), and the power acceptable by the battery (4) so ​​that the powertrain and the traction battery (4) are controlled in an operating mode corresponding to a plug-in hybrid vehicle or a non-plug-in hybrid vehicle, as a function of a switching signal.Figure for abstract: Fig 1.

Description

Title of the invention: Plug-in hybrid motor vehicle equipped with a powertrain, controlled as a plug-in hybrid vehicle or as a hybrid vehicle. Technical field

[0001] The technical field of the invention is the management of traction batteries for motor vehicles, and in particular for hybrid electric vehicles. Prior techniques

[0002] Within the range of certain manufacturers, hybrid and rechargeable hybrid vehicles ("plug-in hybrid" in English) have many parts in common, notably at the electronic and electrical level, in particular at the level of the powertrain. We will refer to the figure [Fig.l] schematically illustrating a hybrid vehicle, rechargeable or not. Within the powertrain, only the set of high-voltage batteries 4 and the on-board charger differ. Indeed, the battery of a PHEV rechargeable hybrid vehicle (acronym for "plug-in hybrid electrical vehicle") is much larger in stored energy capacity, size and mass than in a HEV hybrid vehicle (acronym for "hybrid electrical vehicle"). Obviously, the HEV hybrid vehicle does not have an on-board charger.

[0003] Among the common parts, we can cite the internal combustion engine 2, the electric traction machine 3, the hybrid starter and generator HSG (English acronym for “Hybrid Starter & Generator”), the DC-DC converter, the gearbox, and the low voltage network.

[0004] The powertrain is responsible for torque management and is necessary to set the vehicle in motion. It is electronically controlled by a set of 5 electronic control units ECUs (English acronym for "Electronic Control Unit") connected by a CAN bus (English acronym for "Common Area Network").

[0005] The set 5 of electronic control units ECUs is controlled according to a master-slave scheme, with a master unit controlling slave units. The master unit is called the HEVC (Hybrid Electric Vehicle Controller) main electronic control unit, and each slave ECU is dedicated to controlling an actuator to carry out the request received from the HEVC main electronic control unit.

[0006] The development of a HEVC main electronic control unit differs depending on the vehicle concerned. For example, the battery of a plug-in hybrid vehicle PHEV is fully utilized, whereas the battery of a HEV hybrid vehicle will be controlled to remain centered at an average state of charge.

[0007] In addition, the battery management electronic control unit BMS (acronym for "Battery Management System") is specific for each high voltage battery, due to the consideration of the energy capacity, and the power performance of each set of batteries. The battery management electronic control unit BMS also monitors the set of batteries and communicates the power available for traction or regenerative braking to the main HEVC electronic control unit.

[0008] In both the development and prototyping phases, HEV hybrid vehicles and PHEV plug-in hybrid vehicles are assembled in a similar manner with similar off-the-shelf parts. Only the battery pack and the programming of the ECUs differ. This results in a high research and development cost due to the need for different vehicles to test the design of HEV hybrid vehicles on the one hand and PHEV plug-in hybrid vehicles on the other.

[0009] There is a need for a control method that can reduce these costs by allowing the development of HEV hybrid vehicles and PHEV plug-in hybrid vehicles on the same prototype.

[0010] From the state of the prior art, document US 10,384,667B2 is known, describing a system and a method for implementing operating modes and dynamic controls for hybrid vehicles.

[0011] This document focuses on the management of a vehicle's battery and does not solve the technical problem stated above. Statement of the invention

[0012] The subject of the invention is a plug-in hybrid motor vehicle provided with a powertrain comprising at least one battery and at least one electric motor, the powertrain comprising an electronic control unit for battery management and a main electronic control unit. The powertrain comprises an interface between the main electronic control unit and the electronic control unit for battery management, the interface modifying information communicated by the electronic control unit for battery management to the main electronic control unit as to the usable state of charge of the battery, the energy acceptable by the battery, and the power acceptable by the battery so that the powertrain and the traction battery are controlled in a first operating mode corresponding to a plug-in hybrid vehicle or in a second operating mode corresponding to 。 a non-rechargeable hybrid vehicle based on a switching signal.

[0013] The switching signal can come from a human-machine interface of the vehicle or from a remote server.

[0014] The interface may be in the form of a control method carried out by at least one of the electronic control units of the powertrain, in particular the main electronic control unit and the main electronic control unit.

[0015] The interface may be in the form of an additional electronic control unit, configured to carry out a control method, the additional electronic control unit being arranged between the main electronic control unit and the battery management electronic control unit.

[0016] Another object of the invention is a method for controlling a motor vehicle as described above comprising the following steps for switching from the first operating mode to the second operating mode:

[0017] a. an apparent usable state of charge is defined extending from a lower limit to an upper limit, the lower limit corresponding to a lower limit of usable state of charge of a plug-in hybrid vehicle received from the battery management electronic control unit, the upper limit being set so that the usable charge corresponds to the usable charge in a hybrid vehicle, and the apparent usable state of charge transmitted by the battery management electronic control unit to the main electronic control unit is replaced by the apparent usable state of charge.

[0018] b. an apparent energy admissible by the battery is defined as a function of the upper limit of the apparent usable state of charge and the lower limit of the apparent usable state of charge and the energy admissible by the battery transmitted by the electronic control unit for battery management to the main electronic control unit is replaced by the apparent energy admissible by the battery, and

[0019] c. an apparent traction power and an apparent regeneration power are defined, each depending on the apparent usable state of charge and a cell voltage defined by the construction of the battery, and the traction power and the regeneration power transmitted by the electronic battery management control unit to the main electronic control unit are replaced respectively by apparent traction power and an apparent regeneration power.

[0020] The upper limit of the usable state of charge may depend on the battery temperature.

[0021] The admissible energy may depend on the temperature of the battery.

[0022] The apparent power in traction and the apparent power in regeneration can each depend on the temperature of the battery.

[0023] To switch from the second operating mode to the first operating mode, it is possible to interrupt the replacement of the usable state of charge, the energy admissible by the battery, the traction power and the regeneration power.

[0024] The vehicle and the method have the advantage of reducing the energy and power made available to the drive train as a function of the reduction in the usable state of charge due to the transition from a PHEV plug-in hybrid operating mode to a HEV hybrid.

[0025] Another advantage is that the PHEV plug-in hybrid vehicle then behaves in all respects like a HEV hybrid vehicle, in particular by maintaining a sufficient state of charge in the battery due to regenerative braking alone and the arbitration between internal combustion engine and electric machine, without depending on external recharging. Brief description of the drawings

[0026] Other aims, characteristics and advantages of the invention will appear on reading the following description, given solely by way of non-limiting example and made with reference to the appended drawings in which:

[0027] - figure [Fig.l] illustrates the main common elements of a vehicle at hybrid or plug-in hybrid car,

[0028] - Figure [Fig.2] illustrates the main elements of a set of units of electronic control controlling the motor vehicle according to the invention. Detailed description

[0029] Based on the observation that HEV hybrid vehicles and PHEV plug-in hybrid vehicles are particularly similar in terms of design and components, the inventor had the idea of ​​a system and method for controlling a PHEV plug-in hybrid vehicle allowing it to behave like a HEV hybrid vehicle or like a PEV plug-in hybrid vehicle. The transition from one operating mode to the other can be activated via the vehicle's human-machine interface, or a remote connection, for example to the vehicle manufacturer's servers. The transition from one operating mode to the other can be activated after the user has subscribed to a service allowing additional capacity and access to the on-board charger present in his vehicle to be unlocked.

[0030] The system comprises an additional electronic control unit 6 located between the BMS battery management electronic control unit and the HEVC main electronic control unit, making it possible to intercept and modify the requests exchanged between the HEVC main electronic control unit and the unit electronic control unit for battery management BMS. Figure [Fig.2] illustrates such an arrangement very schematically. The modification is carried out intelligently according to stored parameters. The additional electronic control unit 6 is connected to the CAN network and can propagate information to the slave electronic control units ECUs. Indeed, the modification of requests to the electronic control unit for battery management BMS has repercussions on the other electronic control units ECUs. For example, if the energy request to satisfy a torque request from the electric motor cannot be satisfied, the torque request from the thermal engine must be created or modified in order to compensate for the unrealized torque.

[0031] In order to simulate the presence of a HEV hybrid vehicle battery in a PHEV plug-in hybrid vehicle, and more generally, to transform a HEV hybrid vehicle so that it behaves like a HEV hybrid vehicle, the additional electronic control unit 6 modifies at least three pieces of information before their arrival in the HEVC main electronic control unit. These are the state of charge, the total capacity of the battery, and the available energy.

[0032] A first part of the additional electronic control unit 6 is dedicated to processing the charge status information.

[0033] All hybrid vehicles, whether HEV hybrids or PHEV plug-in hybrids, employ a reduced value of the battery state of charge BSOC (acronym for "Battery State of Charge") compared to the actual state of charge, reserving a high margin and a low margin in order to avoid damage to the battery cells. This reduced state of charge is called the usable state of charge USOC (acronym for "Useable State Of Charge").

[0034] The usable state of charge of the USOC battery of a PHEV plug-in hybrid vehicle thus extends from 15% to 95% of the total state of charge of the BSOC battery}0Q%.

[0035] The usable state of charge of the USOC battery of the high voltage battery of a HEV hybrid vehicle, on the other hand, ranges from 30% to 80% of the total state of charge of the BSOC battery 100%.

[0036] The first part of the additional electronic control unit 6 has the function of reducing the range of values ​​accessible to the usable state of charge of the battery USOC of a plug-in hybrid vehicle PHEV, by defining an apparent usable state of charge USOC' so that it extends from a lower limit USOC\}%, in particular equal to 15% of the total state of charge of the battery BSOC to an upper limit USOCimh in particular equal to 22% of the total state of charge of the battery BSOC 100%. Thus defined, the apparent usable state of charge USOC' of the plug-in hybrid vehicle PHEV corresponds to the usable state of charge USOC of a hybrid vehicle HEV.

[0037] The lower limit of 15% is set to protect the battery from damage.

[0038] It is thus understood that the lower limit USOC'0% of the apparent usable state of charge of the PHEV plug-in hybrid vehicle is kept equal to the lower limit USOC^ of the usable state of charge of a PHEV plug-in hybrid vehicle.

[0039] [Math.l] usoc^ usoc^

[0040] The upper limit USOC' 100% of the apparent usable state of charge of the PHEV plug-in hybrid vehicle is chosen so as to have a quantity of energy comparable to the quantity of energy in the battery of a HEV hybrid vehicle. Indeed, the battery of a HEV hybrid vehicle has a much lower capacity (of the order of 1kWh to 2kWh) than that of a PHEV plug-in hybrid vehicle (of the order of 10kWh).

[0041] In a particular embodiment, the upper limit OS OC' 100% is indexed on the temperature of the battery TBatt to take into account the reduction in the available charge in cold conditions.

[0042] A new upper limit USOCm of the apparent usable state of charge is then defined, depending on the apparent state of charge USOC\qq% and the battery temperature TBatt.

[0043] [Math.2] USOC' ioo% — U SOC reduction^TBat^

[0044] A second part of the additional electronic control unit 6 is dedicated to determining an apparent energy admissible by the battery during regenerative braking. In order for the system to operate, the energy that can be accepted must be determined in accordance with the state of charge limits imposed by the first part of the additional electronic control unit 6.

[0045] The second part of the additional electronic control unit 6 thus overrides the original data relating to the battery and replaces it with the new ones.

[0046] Here too, in a particular embodiment, the admissible apparent energy E' depends on the temperature of the battery TBatt.

[0047] [Math.3] £" = e2 (USOC TBatt} -e1 (U SOC TBatt}

[0048] A third part of the additional electronic control unit 6 is dedicated to adapting the power available at the battery level both in traction and in regeneration. Indeed, in traction the battery must be able to supply energy to at least one electric motor to provide engine torque. It must also be capable of receiving energy so that the at least one electric motor can provide resistive torque during regenerative braking.

[0049] As an apparent usable state of charge USOC' is simulated, the third part of the additional electronic control unit 6 must replace the available power setpoints coming from the battery management electronic control unit BMS with appropriate values, taking into account the simulated apparent usable state of charge VSOC.

[0050] The third part of the additional electronic control unit 6 determines an apparent traction power setpoint P'Trac depending on the state of charge of the battery BSOC, the temperature of the battery TBath and the voltage of the cell VcelI

[0051] In a particular embodiment, the third part of the additional electronic control unit 6 is configured to apply a degraded operating mode when the voltage falls below a lower limit of the cell voltage consisting of reducing the apparent traction power in order to protect the battery. Equation [Math 4] accounts for such operation, the function rChw accounting for the degraded operation when the voltage is too low.

[0052] [Math.4] P'r^ = PT„ ( BSOC, TM ) -

[0053] Similarly, the third part of the additional electronic control unit 6 determines an apparent power setpoint in regeneration P'Reoe depending on the state of charge of the battery BSOC, the temperature of the battery TBatt, and the voltage of the cell Vceii.

[0054] In a particular embodiment, the third part of the additional electronic control unit 6 is configured to apply a degraded operating mode when the voltage exceeds an upper limit of the cell voltage consisting of reducing the apparent traction power in order to protect the battery. Equation [Math 5] accounts for such operation, the function accounting for the degraded operation when the voltage is too high

[0055] [Math.5] PRege = PRjBSOC, TBan)

[0056] The control system has been described above as comprising an additional electronic control unit 6. However, the functions of the additional electronic control unit 6 can be distributed between the main electronic control unit HEVC and the battery management electronic control unit BMS so as not to require the addition of a hardware component. discreet.

Claims

Claims

1. Hybrid motor vehicle provided with a powertrain comprising at least one battery (4) and at least one electric motor (3), the powertrain comprising a battery management electronic control unit (BMS) and a main electronic control unit (HEVC), characterized in that the powertrain comprises an interface (6) between the main electronic control unit (HEVC) and the battery management electronic control unit (BMS), the interface (6) modifying information communicated by the battery management electronic control unit (BMS) to the main electronic control unit (HEVC) as to the usable state of charge of the battery (4), the energy acceptable by the battery (4), and the power acceptable by the battery (4),such that the drive train and the traction battery (4) are controlled in a first operating mode corresponding to a plug-in hybrid vehicle or in a second operating mode corresponding to a non-plug-in hybrid vehicle depending on a switching signal.,

2. A motor vehicle according to claim 1, wherein the switching signal comes from a human-machine interface of the vehicle or from a remote server.

3. Motor vehicle according to any one of claims 1 or 2, in which the interface is in the form of a control method carried out by at least one of the electronic control units of the powertrain, in particular the main electronic control unit (HEVC) and the main electronic control unit (HEVC).

4. A motor vehicle according to any one of claims 1 or 2, wherein the interface is in the form of an additional electronic control unit (6), configured to carry out a control method, the additional electronic control unit (6) being arranged between the main electronic control unit (HEVC) and the battery management electronic control unit (BMS).

5. Method for controlling a motor vehicle equipped with a powertrain comprising at least one battery (4) and at least one electric motor (3), the powertrain comprising a control unit battery management electronics (BMS) and a main electronic control unit (HEVC), characterized in that the powertrain comprises an interface (6) between the main electronic control unit (HEVC) and the battery management electronics control unit (BMS), the interface (6) modifying information communicated by the battery management electronics control unit (BMS) to the main electronic control unit (HEVC) as to the usable state of charge of the battery (4), the energy acceptable by the battery (4), and the power acceptable by the battery (4),such that the powertrain and the powertrain battery (4) are controlled in a first operating mode corresponding to a plug-in hybrid vehicle or in a second operating mode corresponding to a non-plug-in hybrid vehicle as a function of a switching signal at least one of the electronic control units of the powertrain, in particular the main electronic control unit (HEVC) and the main electronic control unit (HEVC) or an additional electronic control unit (6) arranged between the main electronic control unit (HEVC) and the battery management electronic control unit (BMS) performing the following steps to switch from the first operating mode to the second operating mode:, a. defining an apparent usable state of charge extending from a lower limit to an upper limit, the lower limit corresponding to a lower limit of usable state of charge of a plug-in hybrid vehicle received from the battery management electronic control unit (BMS), the upper limit being set such that the usable charge corresponds to the usable charge in a non-plug-in hybrid vehicle, and replacing the apparent usable state of charge transmitted by the battery management electronic control unit (BMS) to the main electronic control unit (HEVC) with the apparent usable state of charge. b. An apparent energy admissible by the battery (4) is defined as a function of the upper limit of the apparent usable state of charge and the lower limit of the apparent usable state of charge and the admissible energy is replaced by the battery (4) transmitted by the battery management electronic control unit (BMS) to the main electronic control unit (HEVC) by the apparent energy admissible by the battery (4), and c. an apparent traction power and an apparent regeneration power are defined each as a function of the apparent usable state of charge and a cell voltage defined by construction of the battery (4), and the traction power and the regeneration power transmitted by the battery management electronic control unit (BMS) to the main electronic control unit (HEVC) are replaced respectively by the apparent traction power and the apparent regeneration power.

6. A control method according to claim 5, wherein the upper limit of the usable state of charge depends on the temperature of the battery (4).

7. Control method according to claim 5, wherein the admissible energy depends on the temperature of the battery (4).

8. A control method according to claim 5, wherein the apparent traction power and the apparent regeneration power each depend on the temperature of the battery (4).

9. Control method according to claim 5, in which to switch from the second operating mode to the first operating mode, the replacement of the usable state of charge, the energy admissible by the battery (4), the traction power and the regeneration power is interrupted.

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