METHOD FOR REGULATING THE POWER OF A HIGH-VOLTAGE BATTERY OF AN ELECTRIC OR HYBRID MOTOR VEHICLE

Abstract

The invention relates to a method for regulating an electric current of a high-voltage battery of an electric or hybrid motor vehicle, said vehicle comprising a DC / DC voltage converter and a set of electrical components, each electrical component having a voltage range and a priority value, the high-voltage battery having a temperature and a state of charge, characterized in that said method comprises determining a minimum voltage value (E1) of the DC / DC voltage converter; an optimal minimum voltage and / or an optimal maximum voltage (E2); a correction value (E3); an optimal regulated minimum voltage and / or an optimal regulated maximum voltage (E4); a first limit power value in discharge (E8) of said battery and a regulation step (E10). Figure 1

Description

Title of the invention: METHOD FOR REGULATING THE POWER OF A HIGH-VOLTAGE BATTERY OF AN ELECTRIC OR HYBRID MOTOR VEHICLE

[0001] The invention relates to a high voltage battery of an electric or hybrid motor vehicle and more particularly to the power of the battery whose electrical energy is directed towards the electrical components of the vehicle.

[0002] Known from the prior art is a patent application WO2022229523 which describes a method for monitoring a battery in a low voltage network of a motor vehicle. The battery is a 12V battery. The method involves determining an electrical diagnostic requirement based on tests on vehicle components, leading to the updating of a requirement variable. The specific control of the electric battery is carried out by applying a predetermined voltage for an initial duration based on the diagnostic requirement variable. A diagnostic step evaluates various parameters of the battery, followed by an analysis to define a reliability status. Then, the diagnostic status of the battery is determined based on the characteristic parameters and the status.The method also includes the management of tests and conditions during the update of the diagnostic need variable, as well as aspects related to the safety and reliability of the characteristic parameters. The method is implemented by a control unit. However, a drawback remains. The method allows the management of the low voltage network. However, the low voltage network allows the power supply of electrical equipment not necessary for the operation of the vehicle, that is to say for its movement. The vehicle movement functions are provided by the high voltage battery, and consequently by the high voltage network. It is therefore more important to ensure the management of the high voltage battery rather than the management of the 12V battery.

[0003] The objective of the present invention is to remedy these drawbacks by proposing a method for managing the power of the high voltage battery.

[0004] To achieve this objective, the invention proposes a method for regulating the power of a high-voltage battery of an electric or hybrid motor vehicle, said vehicle comprising a DC / DC voltage converter and a set of electrical components, each electrical component having a voltage range and a priority value, said voltage range being a set of voltages varying between a minimum voltage and a maximum voltage for which the electrical component operates, said priority value being a fictitious value attributed to the electrical component to determine its relative importance compared to the others electrical components, the high-voltage battery having a temperature and a state of charge, characterized in that said method comprises the following steps: - a step of determining a minimum voltage of the DC / DC voltage converter as a function of the temperature and the state of charge; - a step of determining an optimal minimum voltage and / or an optimal maximum voltage as a function of the minimum voltage of the DC / DC voltage converter, the active electrical components, the voltage range of each electrical component and the priority value of each electrical component; - a step of determining a correction value as a function of a maximum voltage threshold value of the correction; - a step of calculating an optimal minimum voltage regulated as a function of the determined optimal minimum voltage and the correction value and / or an optimal maximum voltage regulated as a function of the determined optimal maximum voltage and the correction value; - a step of determining an internal discharge resistance of said battery as a function of the calculated minimum optimal regulated voltage and / or as a function of the calculated maximum optimal regulated voltage; - a step of determining a first limit current in discharge as a function of the calculated minimum optimal regulated voltage and / or the calculated maximum optimal regulated voltage; - a step of determining an open-circuit voltage of said battery; - a step of determining a first discharge limit power of said battery as a function of the first discharge limit current, the no-load voltage, the calculated minimum optimal regulated voltage, the calculated maximum optimal regulated voltage, and a second discharge limit power independent of the calculated minimum optimal regulated voltage and / or the calculated maximum optimal regulated voltage; - a step of comparing the power consumed by the battery with the first limit power in discharge; - a step of regulating the power consumed by the battery by the PID regulator in a predetermined duration when the power consumed by the battery is lower than the limit power in discharge.

[0005] Thanks to the invention, the power delivered by the battery is regulated so as to guarantee the operation of the electrical components.

[0006] Advantageously, during said step of determining a minimum voltage, the minimum voltage is calculated by the formula T ftT,™,; SOC ; ? hvb 1 '-'DCDC J HV& HVB) corresponding to the battery temperature and SOCHVB corresponding to the state of battery charge.

[0007] Preferably, during said step of determining the correction value (E3), the correction value is calculated by the formula A UCorr-max^min^U^p, ^Kp*e + KD^ + K^e^dt^ j corresponding to a maximum voltage threshold value of the correction; corresponding to an error value between the determined optimal minimum voltage or the determined optimal maximum voltage and an instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at a determined instant; Kp corresponding to a proportional coefficient of the PID regulator, KD corresponding to a coefficient derived from the PID regulator and corresponding to an integral coefficient of the PID regulator.

[0008] Preferably, the error value £ is calculated by the following formula: p — with being the determined optimal minimum voltage and bu Optim u HVB u Optim 1 ^hvb being the instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at the determined instant or by the formula p—l J%a?- - Twith TjMax being the determined optimal maximum voltage and cu Optim u HVB u Optim 1 ^hvb being the instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at the determined instant.

[0009] Advantageously, during said calculation step, the optimal minimum regulated voltage is calculated by the formula T—rjMin , A TJX , cor- ° ' OptimReg — Optim ' Corr u Optim corresponding to the determined minimum optimal voltage and A UCarr corresponding to the correction value and / or the maximum optimal regulated voltage is calculated by the formula™ „ ~ n^ax +ATL ■ J corresponding to the maximum voltage OptimReg u Optim M u Qptun r determined optimal and A UC(,rr corresponding to the correction value.

[0010] Preferably, said predetermined duration is less than 150 ms.

[0011] This is the maximum time before the battery contactors open, causing the electrical power to be cut off.

[0012] Advantageously, during said step of determining an optimal minimum voltage and / or an optimal maximum voltage, said optimal minimum voltage and / or said optimal maximum voltage are determined by implementing the following steps: - a step of comparing an overall minimum voltage and an overall maximum voltage, said overall minimum voltage corresponding to the maximum of the minimum voltages of said set of electrical components and said overall maximum voltage corresponding to the minimum of the maximum voltages of said set of electrical components; - a step of determining a final minimum voltage and a maximum voltage final, said final minimum voltage being equal to said overall minimum voltage and said final maximum voltage being equal to the overall maximum voltage when the overall maximum voltage is greater than the overall minimum voltage; or a step of calculating the overall minimum voltage by the formula UminG = max (U^tor with the highest priority value) and a priority value associated with the minimum voltage Priority,, by the formula itonP Priority = max(PriorityveetOÎ)and global maximum voltage by the formula UmaxG = min(uXîxOi with the highest priority value) and a value of priority associated with the maximum voltage Priority,, by the formula '^maxP Priority,, = max| Priority'Ttor -'tuaxP \ Umax , when said overall maximum voltage is in less than or equal to the overall minimum voltage and a step of determining the final minimum voltage and the final maximum voltage during which the priority values are compared, said final minimum voltage being equal to mayuï““) and

[0013]

[0014]

[0015] said final maximum voltage being equal to said final minimum voltage when the priority value associated with the minimum voltage is greater than the priority value associated with the maximum voltage, said final maximum voltage being equal to mi^U^x01) and said final minimum voltage being equal to said final maximum voltage when the priority value associated with the minimum voltage is less than the priority value associated with the maximum voltage, said final maximum voltage being calculated by the formula rr _ min(U^pr)+ max(U^p*) and said minimum voltage v^maxF —' 2 final being equal to said final maximum voltage when the priority value associated with the minimum voltage is equal to the priority value associated with the maximum voltage; - a step of calculating the optimal minimum voltage by the formula UminOpt — UminF + Offset^ with Offsetmin corresponding to a predetermined margin applicable to the final minimum voltage and / or the optimal maximum voltage by the formula UmaxQpt = UmaxF + Offsetmax with Offsetmin corresponding to a predetermined margin applicable to the final maximum voltage. The invention also relates to a control unit for a high-voltage battery of an electric or hybrid motor vehicle implementing said method described above. Furthermore, the invention relates to an electric or hybrid motor vehicle comprising a control unit for a high-voltage battery previously described. The invention will be further detailed by the description of non-limiting embodiments mitatives, and on the basis of the appended figures illustrating variants of the invention, in which: - [Fig.l] schematically illustrates, in the form of a flowchart, a method for regulating the power of a high-voltage battery of an electric or hybrid motor vehicle according to one embodiment of the invention; - [Fig.2] schematically illustrates, in the form of a flowchart, a process of determining the optimal minimum voltage and / or the optimal maximum voltage during said step of determining the optimal minimum voltage and / or the optimal maximum voltage.

[0016] A method for regulating the power of a high-voltage battery of an electric or hybrid motor vehicle is schematically illustrated in Figure 1, in the form of a flowchart. The battery has a temperature and a state of charge. The battery includes a PID regulator (acronym meaning Proportional, Integral and Derivative). The vehicle includes a DC / DC voltage converter (acronym meaning Direct Current to Direct Current). The vehicle includes a set of electrical components, each electrical component of which has a voltage range and a priority value. The voltage range corresponds to a set of voltages varying between a minimum voltage and a maximum voltage for which the electrical component operates.In other words, when the voltage of the electrical component is lower than the lowest voltage and when the voltage of the electrical component is higher than the highest voltage, then the electrical component is not capable of functioning. The priority value is a value assigned to each component to define a hierarchy between the electrical components. Thus, an electrical safety component will have a higher priority value than an electrical comfort component. Indeed, the safety of a vehicle passenger is prioritized over their comfort. For example, it is more important that an airbag be activated rather than a passenger compartment heating system. The objective of the invention is to guarantee the operation of the electrical components while allowing the high-voltage battery to provide maximum power.In a step of determining a minimum voltage El of the DC / DC converter, the minimum voltage is determined based on the battery temperature and based on the battery charge state. The minimum voltage of the DC / DC converter represents the minimum voltage required for the optimal operation of the converter. The DC / DC converter plays a crucial role in converting the DC voltage of the battery into a voltage suitable for the needs of the vehicle's electrical components, each component having a voltage range. Thus, the minimum voltage of the DC / DC converter is essential to ensure reliable and efficient operation of all electrical components. of the vehicle, thus contributing to the overall performance of the vehicle's electrical system. Preferably, the minimum voltage is calculated by the formula Udcdc ~ SOChvb) ' hvb corresponding to the battery temperature and SOCHVB corresponding to the state of charge of the battery. During a step of determining an optimal minimum voltage and / or an optimal maximum voltage E2, the optimal minimum voltage and / or the optimal maximum voltage are determined based on the minimum voltage of the DC / DC voltage converter determined during the step of determining a minimum voltage El, but also based on the active electrical components of said vehicle, the voltage range of each electrical component and the priority value assigned to each electrical component. The optimal minimum voltage is the ideal minimum voltage necessary to ensure optimal operation of the vehicle's electrical components. The optimal maximum voltage is the ideal maximum voltage necessary to ensure optimal operation of the vehicle's electrical components.By integrating these parameters, the optimal minimum voltage and / or the optimal maximum voltage are calculated to ensure that each electrical component receives a voltage adequate for their operation while respecting its specific requirements. Thus, the optimal minimum voltage and the optimal maximum voltage contribute to the optimization of the overall performance of the vehicle's electrical system, by ensuring a balance between the energy needs of each component and the constraints of the high-voltage battery. During a step of determining a correction value E3, the correction value is determined according to a maximum voltage threshold value of the correction. The maximum voltage threshold value of the correction is a predetermined value beyond which an additional correction is not applied. Advantageously, the correction value is calculated by the formula . A UCorr = max^O, minU™;, (Kp*s + K^e^dt) jj corresponding to a maximum voltage threshold value of the correction; e corresponding to an error value between the determined optimum minimum voltage or optimum maximum voltage and the instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at a determined instant; Kp corresponding to a proportional coefficient of the PID regulator, KD corresponding to a derived coefficient of the PID regulator and Ki corresponding to an integral coefficient of the PID regulator. Preferably, the error value e is calculated by the following formula: P — [ _ J with / [Mm being the determined optimal minimum voltage and U^vb being the instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at the determined instant or by the formula p — with JJ^a* being the determined optimal maximum voltage and fc — c Optim u HVB u Optim 1 ^hvb being the instantaneous voltage of the high-voltage battery corresponding to the voltage of the high-voltage battery at the determined instant. In a calculation step E4, the minimum optimal regulated voltage is determined as a function of the previously determined minimum optimal voltage and the correction value. The maximum optimal regulated voltage is determined as a function of the previously determined maximum optimal voltage and the correction value. Preferably, the minimum optimal regulated voltage is calculated by the formula / o —J 4- At l h. ■> corresponding to the minimum voltage v7 OptimReg Optim tv Cm-r Optim r determined optimal and A UCorr corresponding to the correction value. The maximum optimal regulated voltage is calculated by the formula jjMax jjMax corresponding to the maximum voltage u OptimReg u Optim u Qorp U Optim Fdetermined and A UCorr corresponding to the correction value. During a step of determining an internal resistance during discharge E5 of the battery, the internal resistance during discharge of the battery is determined according to the calculated minimum optimal regulated voltage and / or the calculated maximum optimal regulated voltage. The internal resistance corresponds to the difficulty of the electrical energy to circulate in said battery. During a step of determining a first limit current during discharge E6, the first limit current during discharge is determined according to the calculated minimum optimal regulated voltage and / or the calculated maximum optimal regulated voltage. The limit current during discharge corresponds to the maximum electric current that the battery can transmit without deteriorating. During a step of determining an open-circuit voltage E7 of said battery, the open-circuit voltage is determined.The no-load voltage corresponds to the voltage of the battery when said battery is not supplying electrical energy. In other words, the battery is at rest. During a step of determining a first discharge limit power E8, the first discharge limit power is determined as a function of the first discharge limit current, the no-load voltage, the calculated optimal regulated minimum voltage, the calculated optimal regulated maximum voltage and a second discharge limit power independent of the calculated optimal regulated minimum voltage and / or the calculated optimal regulated maximum voltage. The discharge limit power is the maximum power that the battery can supply without deteriorating when said battery is supplying one or more electrical components. During a comparison step E9, a power consumed by the battery is compared to the first discharge limit power.During an E10 regulation step, when the power consumed by the battery is lower than the discharge power limit. The power consumed by the battery is regulated by the PID regulator. in a predetermined duration. Preferably, said predetermined duration is less than 150 ms. Thus, the opening of the battery contactors is avoided so that the electrical energy is not cut off. When the power consumed by the battery is less than the first power limit in discharge, we speak of an anomaly. The PID regulator is a control device used to regulate a predetermined variable, in this case the power consumed by said battery. The PID regulator has a proportional coefficient, an integral coefficient and a derivative coefficient. The proportional coefficient corresponds to the proportion between the power consumed by the battery and the first power limit in discharge. The integral coefficient corresponds to the accumulator potential of the anomalies over time. The derivative coefficient corresponds to the speed at which the anomaly varies during regulation.The invention also relates to a control unit implementing said method and an electric or hybrid motor vehicle comprising said control unit.

[0017] A method for determining the optimal minimum voltage and the optimal maximum voltage during said step of determining the optimal minimum voltage and the optimal maximum voltage E2 is schematically illustrated in the form of a flowchart. Preferably, the optimal minimum voltage and the optimal maximum voltage are obtained by implementing several steps. First, an overall minimum voltage and an overall maximum voltage are compared. The overall minimum voltage corresponding to the maximum of the minimum voltages of said set of electrical components. The overall maximum voltage corresponding to the minimum of the maximum voltages of said set of electrical components. Then, a final minimum voltage and a final maximum voltage are determined. final minimum voltage being equal to said overall minimum voltage and said final maximum voltage being equal to the overall maximum voltage when the overall maximum voltage is greater than the overall minimum voltage. If this is not the case, then a step of calculating the overall minimum voltage is implemented by the formula UminG = rnax LI^^01 with greater priority value) and a priority value associated with the minimum voltage Priorityy by the formula Priority = max(Priorityvect°r)' global maximum voltage is also E / niiip \ * / calculated by the formula UmaxG = min(uXax°r with the highest priority value) as well as a priority value associated with the maximum voltage Priority^. by the formula PriorityTT = maxfpriority)^01 UmaxP X ) when said overall maximum voltage is in less than or equal to the overall minimum voltage. A step of determining the final minimum voltage and the final maximum voltage is implemented during which the priority values are compared. The final minimum voltage is equal to max(U^tO1) ct 'a final maximum voltage being equal to said final minimum voltage when the priority value associated with the minimum voltage is greater than the priority value associated with the maximum voltage. The final maximum voltage is equal to min(Um^tor) ct l^ite final minimum voltage is equal to said final maximum voltage when the priority value associated with the minimum voltage is less than the priority value associated with the maximum voltage. The final maximum voltage is calculated by the formula rr _ ct said minimum voltage '-'maxF —' 2 final is equal to said final maximum voltage when the priority value associated with the minimum voltage is equal to the priority value associated with the maximum voltage. Finally, the optimal minimum voltage is calculated based on the final minimum voltage and a predetermined margin applicable to the final minimum voltage Offsetmin by the following formula: Umjnopt —Offsetinin. The optimal maximum voltage is calculated based on the final maximum voltage and a predetermined margin applicable to the final maximum voltage Offsetmax by the following formula: Umaxopt — Umaxp + Offsetmax. The predetermined margin applicable to the final minimum voltage Offsetmin and the predetermined margin applicable to the final maximum voltage Offsetmax is also determined based on the inaccuracy of the battery voltage measurement.

Claims

1. Claims Method for regulating the power of a high-voltage battery of an electric or hybrid motor vehicle, said vehicle comprising a DC / DC voltage converter and a set of electrical components, each electrical component having a voltage range and a priority value, said voltage range being a set of voltages varying between a minimum voltage and a maximum voltage for which the electrical component operates, said priority value being a fictitious value attributed to the electrical component to determine its relative importance compared to the other electrical components, the high-voltage battery having a temperature and a state of charge, characterized in that said method comprises the following steps: - a step of determining a minimum voltage (El) of the DC / DC voltage converter as a function of the temperature and the state of charge; - a step of determining an optimal minimum voltage and / or an optimal maximum voltage (E2) as a function of the minimum voltage of the DC / DC voltage converter, of the active electrical components, of the voltage range of each electrical component and of the priority value of each electrical component; - a step of determining a correction value (E3) as a function of a maximum voltage threshold value of the correction; - a step of calculating (E4) an optimal minimum voltage regulated as a function of the determined optimal minimum voltage and the correction value and / or an optimal maximum voltage regulated as a function of the determined optimal maximum voltage and the correction value; - a step of determining an internal discharge resistance of said battery (E5) as a function of the calculated optimal regulated minimum voltage and / or as a function of the calculated optimal regulated maximum voltage; - a step of determining a first discharge limit current (E6) as a function of the calculated minimum optimal regulated voltage and / or the calculated maximum optimal regulated voltage; - a step of determining an open-circuit voltage (E7) of said battery; - a step of determining a first limit power in discharge (E8) of said battery as a function of the first discharge limit current, the no-load voltage, the calculated regulated optimum minimum voltage, the calculated regulated optimum maximum voltage, and a second discharge limit power independent of the calculated regulated optimum minimum voltage and / or the calculated regulated optimum maximum voltage; - a step of comparing (E9) a power consumed by the battery with respect to the first discharge limit power; - a step of regulating (E10) the power consumed by the battery by the PID regulator in a predetermined duration when the power consumed by the battery is less than the discharge limit power.

2. Method according to claim 1 characterized in that, during said step of determining a minimum voltage (El), the minimum voltage is calculated by the formula T= f(SOC\.„d\ ; r ^DCDC J y* HVB* HVB) Thvb corresponding to the temperature of the battery and SOCHVB corresponding to the state of charge of the battery.

3. Method according to claim 1 or 2 characterized in that, during said step of determining the correction value (E3), the correction value is calculated by the formula A UCorr = max(0; min( U(Kp*e + KD+ K.*Js*dt pp corresponding to a maximum voltage threshold value of the correction; e corresponding to an error value between the determined optimal minimum voltage or the determined optimal maximum voltage and an instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at a determined instant; Kp corresponding to a proportional coefficient of the PID regulator, Kd corresponding to a derived coefficient of the PID regulator and Kj corresponding to an integral coefficient of the PID regulator.

4. Method according to claim 3 characterized in that the error value e is calculated by the following formula: P — T7%™. _ 7with I rc — o Optmi v HV B u Optm being the determined optimum minimum voltage and U^vB being the instantaneous voltage of the high voltage battery corresponding to the voltage of the high voltage battery at the determined instant or by the formula p — 11 ^ax- - with 71%“* being the optimum maximum voltage de- ~ u Opnm ° HVB u Optim 1 completed and TJ1^» being the instantaneous voltage of the high voltage battery voltage corresponding to the voltage of the high voltage battery at the determined instant.

5. Method according to claim 3 or 4 characterized in that, during said calculation step (E4), the regulated optimal minimum voltage is calculated by the formula / 7^'" „ = J]Min corresponding to the determined optimal minimum voltage and A UCmr corresponding to the correction value and / or the regulated optimal maximum voltage is calculated by the formula T^ax. „ — TJ^ax- + A 77^ , & 1O OptimReg u Optun Cmr ^Optim corresponding to the determined optimal maximum voltage and A UCorr corresponding to the correction value.

6. Method according to any one of claims 1 to 5 characterized in that said predetermined duration is less than 150 ms.

7. Method according to any one of claims 1 to 6 characterized in that, during said step of determining an optimal minimum voltage and / or an optimal maximum voltage (E2), said optimal minimum voltage and / or said optimal maximum voltage are determined by implementing the following steps: - a step of comparing an overall minimum voltage and an overall maximum voltage, said overall minimum voltage corresponding to the maximum of the minimum voltages of said set of electrical components and said overall maximum voltage corresponding to the minimum of the maximum voltages of said set of electrical components;- a step of determining a final minimum voltage and a final maximum voltage, said final minimum voltage being equal to said overall minimum voltage and said final maximum voltage being equal to the overall maximum voltage when the overall maximum voltage is greater than the overall minimum voltage; or a step of calculating the overall minimum voltage by the formula UminG = max^U^01 with the highest priority value) and a priority value associated with the minimum voltage PriorityTT by the formula UminP — max(Priorityvector) and the maximum tensr°n UminP \ Lmm / overall by the formula UmaxG = min(uXîx°r with the highest priority value) and a priority value associated with the maximum voltage PriorityfT by the ^maxP; formula priority E = maJPrioritywhen said overall maximum voltage is less than or equal to the overall minimum voltage and a step of determining the final minimum voltage and the final maximum voltage during which the priority values are compared, said final minimum voltage being equal to max(U^®fO1) and said final maximum voltage being equal to said final minimum voltage when the priority value associated with the minimum voltage is greater than the priority value associated with the maximum voltage, said final maximum voltage being equal to min(uXnx°r^ and final minimum voltage being equal to said final maximum voltage when the priority value associated with the minimum voltage is less than the priority value associated with the maximum voltage,said final maximum voltage being calculated by the formula U _ min(U^^J)-nnax(uXy) and said final minimum voltage being '-'maxF 2 equal to said final maximum voltage when the priority value associated with the minimum voltage is equal to the priority value associated with the maximum voltage; - a step of calculating the optimal minimum voltage by the formula UminOpt - UminF + Offsetmin with Offsetmin corresponding to a predetermined margin applicable to the final minimum voltage and / or the optimal maximum voltage by the formula Umaxopt — UmaxF Off setmax with Off f setmax corresponding to a predetermined margin applicable to the final maximum voltage.,

8. Control unit of a high voltage battery of an electric or hybrid motor vehicle implementing said method of regulating a power of a high voltage battery of an electric or hybrid motor vehicle according to any one of claims 1 to 7.

9. Electric or hybrid motor vehicle comprising a high voltage battery control unit according to claim 8.

Images