Energy management control system

Abstract

Method for controlling the energy distribution in a HEV powertrain, wherein the method comprises the following: Generating a forward-coupling battery power value (P) bat_pwr_ff ) in response to the input, which is a driver torque request (T req_unf ) displays; Generating a feedback battery power modification value (P) bat_pwrmod ) in response to the input, which determines the actual battery power (P bat_act ) and the driver torque request (T req_unf ) displays; and Calculating a final high-voltage battery power requirement (P) bat_em_des ) based on a sum of the forward coupling battery power value (P bat_pwr_ff ) and the feedback battery power modification value (P bat_pwrmod ), characterized by Generating a power machine power estimate (P eng-pwr_est ) based on the power machine time delay (τ eng), of the engine braking torque (T eng_brk ) and the engine speed (ω eng ); Filtering the driver torque request (T req_unf ) using a filter (78) to obtain a filtered driver torque request (T req ) to generate; generating a driver performance estimate (P drv ) based on a product of the filtered driver torque demand (T req ) and a gearbox output shaft speed (ω oss ); where generating the feedback battery power modification value (P bat_pwrmod ) furthermore, a calculation of the feedback battery power modification value (P bat_pwrmod ) based on a difference between the driver performance estimate (P drv ) and the power machine power estimation (P eng_pwr_est ) includes.

Description

TECHNICAL SECTOR

[0001] One or more embodiments relate to a control system for controlling the energy distribution from a battery in a powertrain for a hybrid electric vehicle. GENERAL STATE OF THE ART

[0002] Hybrid electric vehicles (HEVs) use a combination of an internal combustion engine and an electric motor to provide the power needed to propel the vehicle. This arrangement delivers improved fuel economy compared to a vehicle with only an internal combustion engine. One method for improving fuel economy in an HEV is to switch off the internal combustion engine during periods when it is inefficient and not otherwise needed to power the vehicle. In these instances, the electric motor is used to provide all the power required to propel the vehicle.If the driver's power demand increases to such an extent that the electric motor can no longer provide sufficient power to meet the demand, or if the battery's state of charge (SOC) falls below a certain level, the electric motor starts quickly and smoothly in a manner that is almost transparent to the driver. Another method for improving fuel consumption in a HEV is to operate the electric motor only within a high-efficiency range and to regulate the motor to add or subtract power from the total power output as needed to meet the power demand.

[0003] A modular hybrid powertrain (MHT) is a powertrain that incorporates components from a conventional vehicle (e.g., the engine, gearbox, and differential) and includes hybrid components (e.g., the motor, high-voltage battery, clutches) to provide a HEV.

[0004] Document US 8 080 971 B2 concerns a control system for managing the energy distribution from a battery in a powertrain for a hybrid electric vehicle.

[0005] German patent application DE 103 36 758 A1 discloses an idle speed control system for a hybrid vehicle.

[0006] The application US 2011 / 0 137 502 A1 concerns a hybrid industrial vehicle.

[0007] US patent 2011 / 0015838A1 discloses a shift control system for a continuously variable transmission (CVT) comprising a continuously variable transmission mechanism and a sub-transmission mechanism. SUMMARY

[0008] In one embodiment, a method according to claim 1 is provided for controlling the energy distribution in a HEV powertrain. In response to an input indicating a driver torque demand, a forward-feedback battery power value is generated. In response to an input indicating actual battery power and the driver torque demand, a feedback battery power modification value is generated. Based on the sum of the forward-feedback battery power value and the feedback battery power modification value, a high-voltage battery power demand is calculated.

[0009] In a further embodiment, an energy management control system according to claim 7 is provided with a control unit. The control unit generates a driver power demand based on a system-limited sum of a driver torque demand and a transmission torque loss value. The control unit also generates a forward-coupling battery power value as a function of the driver power demand and a power unit power demand. The control unit then calculates a battery power demand in response to the forward-coupling battery power value.

[0010] In yet another embodiment, a hybrid electric vehicle according to claim 13 is provided with a control unit configured to generate an output indicating a gear selection in response to a transmission input speed. A control unit communicates with the control unit and is configured to generate an output indicating a power unit torque command and an engine torque command in response to an input indicating a driver torque request and actual battery power, regardless of the gear selection.

[0011] Therefore, different designs offer one or more advantages. Hybrid electric vehicles (HEVs) use a combination of an internal combustion engine and an electric motor to provide the power needed to propel the vehicle. This arrangement delivers improved fuel economy compared to a vehicle with only an internal combustion engine. Furthermore, the vehicle features a modular hybrid transmission (MHT) with an energy management control system. The energy management control system simplifies the vehicle's control logic by decoupling speed and torque determinations into two independent control variables (gear selection and battery power demand).

[0012] This problem is solved by the features of claims 1, 7 and 13. Advantageous embodiments of the invention are described in the dependent claims. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a schematic representation of a hybrid electric vehicle according to one or more embodiments; Fig. Figure 2 is an enlarged schematic view of a part of the hybrid electric vehicle by Fig. 1; Fig. Figure 3 is a schematic block diagram of an energy management control system; Fig. Figure 4 is an enlarged view of part of the energy management control system of Fig. 3; Fig. 5A is part of a flowchart that describes a procedure for performing the tasks described in Fig. 3 control functions shown for the hybrid electric vehicle from Fig. 1 shows; Fig. 5B is another part of the flowchart of Fig. 5A; and Fig. 5C is yet another part of the flowchart of Fig. 5A. DETAILED DESCRIPTION

[0013] With reference to Fig. Figure 1 is a vehicle corresponding to one or more embodiments and is generally identified by the number 10. In general, vehicle 10 has an energy management control system which offers advantages over existing control systems due to its simplified control. As described below with reference to Fig. As described in section 2, this simplification involves decoupling the speed and torque determinations into two independent control variables (gear selection and battery power demand). Furthermore, the determination of the battery power demand can be simplified even further by disabling a feedback loop in the control system under certain operating conditions, as described below with reference to Fig. 3 - 5C is described.

[0014] The vehicle 10 is a HEV and comprises a power machine 12, an electric machine or motor / generator (M / G) 14, and a transmission 16. An output shaft 18 extends from the transmission 16 and connects to a differential 20. A pair of axle shafts 22 extend from the differential 20, and each axle shaft 22 connects to a drive wheel 24.

[0015] The M / G 14 operates as both a motor and a generator. As a motor, the M / G 14 draws electrical power from a high-voltage battery 26 and generates the torque (T). in ) provides the transmission 16 for driving the vehicle 10. The M / G 14 operates as a generator by converting the engine torque (T) eng ) and / or absorbs the torque from the gearbox 16, thereby charging the high-voltage battery 26.

[0016] The vehicle 10 has a starter 28 for starting the engine 12. The starter 28 draws electrical power from a low-voltage battery 30 and provides the engine 12 with the torque for starting the engine 12. In one or more embodiments, the M / G 14 acts as a starter and draws electrical power from the high-voltage battery 26 and provides the torque for starting the engine 12.

[0017] The vehicle 10 has clutches for selectively disconnecting the motor / gear unit (M / G) 14 and / or the power unit 12 from the drive wheels 24. A disengagement clutch 32 is arranged between the power unit 12 and the M / G 14. The disengagement clutch 32 is actuated to engage or disengage the power unit 12 from the rest of the drivetrain. By disengaging the power unit 12, the vehicle 10 can be driven by the M / G 14 in an electric mode. According to one or more embodiments, a starting clutch 34 is arranged between the M / G 14 and the transmission 16. The starting clutch 34 is actuated to engage or disengage the M / G 14 (and the power unit 12) from the transmission 16. The starting clutch 34 can also be controlled to be partially engaged with the transmission 16. This partial engagement or “grinding” limits the transmission of any vibrations in the drive train to the drive wheels 24.Both the release clutch 32 and the starting clutch 34 are configured as hydraulic clutches according to at least one embodiment. Other embodiments of the vehicle 10 have mechanical or electrical clutches.

[0018] Alternative embodiments of the vehicle 10 feature a torque converter 36 instead of a starting clutch 34, which is arranged between the M / G 14 and the transmission 16. A torque converter 36 is typically less efficient than a starting clutch 34. However, the starting clutch 34 usually requires a more complex control strategy. Therefore, starting from the preferred uses, the vehicle 10 can have either a starting clutch 34 or a torque converter 36.

[0019] Vehicle 10 features a modular hybrid transmission (MHT). An MHT is a powertrain that incorporates components from a conventional vehicle (e.g., engine, gearbox, and differential) and hybrid components (e.g., motor, high-voltage battery, clutches) to provide a hybrid electric vehicle (HEV). The hybrid components are integrated into Fig. 1 generally identified by the number 37. Through the use of many conventional or "adopted" components, the vehicle 10 can benefit from the "cost advantages of mass production", which reduce the overall costs and complexity of the vehicle 10.

[0020] Vehicle 10 features a Vehicle System Control (VSC) for controlling various vehicle systems and subsystems and is generally defined by Block 38 in Fig. Figure 1 shows the VSC 38 comprising several interrelated algorithms distributed across multiple control units in the vehicle 10. For example, the algorithms for controlling the MHT powertrain are divided between an engine control unit (ECU) 40 and a transmission control unit (TCU) 42. The ECU 40 is electrically connected to the engine 12 to control its operation. The TCU 42 is electrically connected to the M / G 14 and the transmission 16 to control their operation. According to one or more embodiments, the ECU 40 and TCU 42 communicate with each other and with other (not shown) control units via a hardline vehicle connection using a common bus protocol (e.g., CAN).Although the illustrated embodiment shows that the functionality of the VSC 38 for controlling the MHT powertrain is contained in two control units (ECU 40 and TCU 42), other embodiments of the HEV 10 have a single VSC control unit or more than two control units for controlling the MHT powertrain.

[0021] The VSC 38's algorithms for controlling the MHT powertrain are simplified into two "degrees of freedom": engine speed and torque. The TCU 42 determines a first independent control variable (gear selection) corresponding to the engine speed. The ECU 40 determines a second independent control variable (battery power demand) corresponding to the torque.

[0022] Fig. Figure 2 shows a simplified block diagram of the VSC 38 algorithms for determining the two independent control variables: gear selection and battery power demand. According to one or more embodiments, the VSC 38 algorithms are described with reference to Fig. 1 and Fig. 2 included in the ECU 40 and the TCU 42.

[0023] With reference to Fig. 1 and Fig. 2. The VSC 38 determines the first independent control variable (gear selection) at block 43. The VSC 38 receives as input (ω oss ) and (ω in), which represent the output shaft speed or the transmission input speed. The VSC 38 also receives an accelerator pedal position signal (APPS) as input, representing a driver request in relation to wheel torque. The input can be received directly as an input signal from individual systems or sensors (not shown) or indirectly as input data via the CAN bus. For example, the output shaft speed (ω) can be oss ) and the gearbox input speed (ω in ) are received as input signals from speed sensors (not shown). At block 43, the VSC 38 determines the gear selection in response to the inputs (ω). oss ), (ω in ) and (APPS) and provides the output (GEAR_cmd) to transmission 16, which represents a gear selection command.

[0024] The gear selection (e.g., first, second, third, etc.) determines the gear ratio of the transmission 16. In a preferred variant, the power unit 12 is an inline power unit. Since the vehicle comprises an inline power unit, a motor / gearbox 14, and a transmission 16 with discrete gear ratios ("gear ratio stages"), the speed calculations across the drivetrain are simplified compared to state-of-the-art HEVs, which have continuously variable transmissions that provide an infinite number of gear ratios. For example, if the release clutch 32 is engaged, then the speed of the motor / gearbox 14 corresponds to the speed of the power unit (ω). eng ). The engine speed (ω) eng The speed of the M / G 14 and the speed of the M / G 14 are the same when the release clutch 32 is fully engaged (no slippage). The output shaft speed (ω) oss) corresponds to the rotational speed of the M / G 14 and the gear ratio of the transmission 16. The rotational speed of each drive wheel 24 corresponds to the output shaft speed (ω). oss ) and the translation of the differential 20. The wheel speed can also be related to the vehicle speed (km / h).

[0025] At block 44, the VSC 38 determines a wheel torque request. The VSC 38 receives as input (T regen ) and (APPS), which provide regenerative braking torque or This represents the driver's request regarding wheel torque. The input can be received directly as an input signal from individual systems or sensors (not shown) or indirectly as input data via the CAN bus. For example, the regenerative braking torque (T) can be regen ) as An input signal is received from a brake system control unit (not shown). The accelerator pedal position (APPS) can as an input signal from an accelerator pedal position sensor (not shown). The VSC 38 determines a wheel torque request at block 44 in response to the inputs (T regen) , (APPS) and (ω oss ) and provides an output (T req ) ready, which represents a driver torque request.

[0026] At block 46, the VSC 38 determines a battery power requirement. The VSC receives as input (PSOC), (P bat_act ) and (ω oss ), which each represent the state of charge maintenance, the actual battery power, and the output shaft speed. The input can be received directly as an input signal from individual systems or sensors (not shown) or indirectly as input data via the CAN bus. For example, the state of charge maintenance (PSOC), the actual battery power (P bat_act ) and the output shaft speed (ω oss) are received as input signals from a battery control unit (not shown). The VSC 38 also receives the driver torque request (T) at block 46. req ). At block 46, the VSC 38 determines the high-voltage battery power demand in response to the inputs (PSOC), (P bat_act ) and (ω oss ) as well as the torque requirement (T req ) and represents the output (P bat_em_des) ready, which represents a final high-voltage battery power requirement.

[0027] At block 47, the VSC 38 compares the driver torque request (T req ) with system limits to issue a torque command (T cmd ) to determine. The system limits represent the specified operating limits for the power unit, the motor, and the battery. The torque distribution between the power unit 12 and the M / G 14 is determined at block 48. The VSC 38 compares the torque command (T cmd) with the final high-voltage battery power requirement (P bat_em_des ) together with the specified data for the power machine to determine the torque contribution (division) required by the power machine 12 and the M / G 14, and provides the corresponding command signals (T cmd_eng ) and (T cmd_m ) ready.

[0028] The gear selection control variable (gear selection) is determined by both HEVs and non-HEVs. For HEVs, the battery power demand control variable (P) is used. bat_em_des ) own. Since the gear selection control variable is determined independently of the high-voltage battery power requirement variable, an HEV 10 and a corresponding non-HEV equipped with the VSC 38 would exhibit similar performance characteristics. For example, both the HEV and the non-HEV would, at approximately the same vehicle speed and / or transmission input speed (ω), in) shift up a gear. The independent control variables are set in such a way that they meet the driver's demands within the limits of the MHT powertrain and subsystems and achieve the desired vehicle performance characteristics (e.g. reduced fuel consumption, low emissions, driving behavior, extended battery life, etc.).

[0029] With reference to Fig. Figure 3 shows a schematic block diagram illustrating the operation of an energy management control system or procedure according to one or more embodiments, and which is generally referred to by the number 50. The energy management control system 50 corresponds to specification blocks 44 and 46 of Fig. 2 for determining the high-voltage battery power requirement (P bat_em_desAccording to one or more embodiments, the energy management control system 50 is included in the ECU 40 and can be implemented in a hardware and / or software control logic, as described in more detail here.

[0030] At the summing connection point 52, the energy management control system 50 determines a driver torque request (T req_unf The energy management control system 50 receives (APPS) and (T) as input. regen ), which represent the driver request regarding wheel torque or the regenerative braking torque. At the summing connection point 52, the energy management control system 50 adds the driver torque request, which is derived from (APPS), to (T regen ), to meet the driver torque request (T req_unf) to calculate. The energy management control system 50 takes into account the efficiency losses in the gearbox 16 by calculating a gearbox torque loss (T) at the summing connection point 54. trans_loss ) for driver torque request (T req_unf ) is added.

[0031] A torque command (T) is sent to the system comparator 56. cmd_unf ) determined. The sum of the driver torque request (T req_unf ) and the transmission torque loss (T trans_loss ) is used with the system torque limits (T sys_max ,T sys_min) compared. The system torque limits are a function of the engine torque limits (T). eng_max , T eng_min ), the engine torque limits (T m _ inst_max ,T m_inst_min ), the battery limits (P elec_chg_lim ,P elec _ dch_lim ), the electrical efficiency ( P sys_loss ) and the engine speed (ω mAccording to one or more embodiments, the maximum system torque (T) sys_max ) a function of (T eng_max , T m_inst_max , P elec_dch_lim ,P sys_loss ,ω m ) and the minimum system torque (T sys_min ) a function of ( T eng_min , T m_inst_min , P elec_chg_lim ,P sys_loss, ω m ).

[0032] The Energy Management Control System 50 evaluates the driver's propulsion requirements in the torque domain rather than the power domain, enabling improved vehicle control. State-of-the-art control systems for hybrid vehicles (not shown) often evaluate the driver's requirements in the power domain, which can lead to calculation errors when the engine speed is zero. These state-of-the-art control systems, operating in the power domain, calculate torque by dividing power by engine speed, which could result in erroneous zero torque values ​​during startup when the engine speed is zero and the torque is not zero. To compensate for this calculation, state-of-the-art power-domain control systems often have substitute torque values ​​for certain operating modes (e.g., engine start).

[0033] The torque command (T cmd_unf) is transferred into the performance domain by (T cmd_unf ) at the multiplication junction 58 with the output shaft speed (ω oss ) is multiplied. This product is added at summing point 60 to determine the system power loss (P). sys_loss) added to the driver performance requirement (P drv_ung ) to determine. The system power loss (P sys_loss ) represents the efficiency losses in the M / G 14 and in the (not shown) power electronics.

[0034] At block 62, a desired high-voltage battery power requirement (P) is met. des_bat_pwrreq ) determined. The desired high-voltage battery power requirement (P des_bat_pwrreq ) is determined based on the optimization of system efficiency and is a function of the driver's power demand (P drv_unf ), the power state of charge conservation (PSOC) and the motor speed (ω mThe power state of charge (PSOC) represents the electrical power available from both the battery and the M / G 14 (when operating as a generator). Vehicle 10 has a sensor (not shown) for providing an output signal (ω). m ) which represents the output speed of the M / G 14.

[0035] A total power demand (P) is applied to the power machine comparator block 64. eng_pwr_tot ) determined. At summing connection point 66, the desired high-voltage battery power requirement (P) is set. des_bar_pwrreq ) from the driver performance requirement (P drv_unf ) is subtracted. This difference is then compared at the power machine comparator block 64 with the maximum and minimum power limits of the power machine (P). eng_max ,P eng_min ) compared to determine the total power requirement of the power unit (P eng_pwr_tot) to determine. The fuel consumption values ​​of the HEV 10 are optimized by operating the engine 12 in a high-efficiency range. The engine limits (P eng_max ,P eng_min ) correspond to this high-efficiency range.

[0036] At the battery comparator 68, the energy management control system 50 determines a system-limited forward coupling high-voltage battery power (P). bat_pwr_ff) At summing connection point 70, the total power requirement of the power units (P) is determined. eng_pwr _ tot ) from the driver performance requirement (P drv_unf ) is subtracted. This difference is then compared at the battery comparator 68 with the battery charging and discharging power limits (P). elec_chg_um ,P elec_dch_lim ) compared to determine the system-limited forward-coupling high-voltage battery power value (P bat_pwr_ff) to determine. The service life of the high-voltage battery 26 is increased by keeping the battery state of charge (SOC) within a predetermined range. The battery limits (P elec_chg_lim ,P elec_dch_lim ) correspond to this area.

[0037] The energy management control system 50 has a feedback loop, which is accessed in Fig. 3 is generally referred to by reference to paragraph 71. The feedback loop 71 provides a correction path for determining torque and power. Under certain conditions, the energy management control system 50 can bypass the feedback loop 71, as described below with reference to Fig. 4 is explained.

[0038] At the power machine comparator block 72, a power machine power estimation (P) is performed. eng_pwr_est ) determined. Function block 74 receives the total power demand of the power machines (P). eng_pwr_tot ) together with a power machine time delay (τ eng), a power machine braking torque value (T eng_brk ) and a power engine speed value (ω) eng ) and determines an achievable power output value (P) eng_ach ). The power machine time delay (τ eng ) represents the time delay or overrun between the provision of a torque command to the machine and the point in time at which the machine's output torque corresponds to the command. The machine's braking torque (T) eng_brk ) represents the value of the engine torque that is converted into electricity by the M / G 14 when it operates as a generator to charge the battery. The engine speed (ω) eng ) represents the output speed of the power machine 12. The achievable power machine output (P) is measured at the power machine comparator block 72. eng_ach ) compared with the engine limits to estimate the engine power (P eng_pwr_est ) to determine.

[0039] The energy management control system 50 determines a driver performance estimate (P) at the summing connection point 76. drv A weighted averaging filter 78 receives the driver torque request (T req_unf ) and eliminates any rapid step changes in the signal to produce a filtered driver torque request (T req ). Subsequently, the energy management control system 50 takes into account the efficiency losses in the gearbox 16 by calculating the gearbox torque loss (T) at the summing connection point 80. trans_loss) for the filtered driver torque request (T req ) is added. The filtered driver torque request (T req ) is compared with the overall system limits at the system comparator 82 and then converted into the power domain by multiplying it with the output shaft speed (ω) at the multiplication junction 83. oss) is multiplied. This product is used at summing connection point 76 to calculate the system power loss (P). sys_loss ) added to estimate driver performance (P drw ) to obtain.

[0040] The output of feedback loop 71 is a feedback high-voltage battery power modification value (P). bat_pwvrmod ), which is determined by a proportional-integral (PI) controller 84. At the summing junction 86, the power machine power estimation (P) is taken. eng_pwr_est ) from the driver performance requirement (P drv ) is subtracted. The difference is compared with the battery limits at battery comparator 88 to determine a feedback high-voltage battery power requirement (P). bat_reqpwrfb ) to determine. The voltage and current of the high-voltage battery 26 are measured, and an actual battery power value (P) is determined. bat_act ) is calculated. The actual battery power (P bat_act) is connected at summing point 90 from (P bat_reqpwrfb ) is subtracted. The PI controller 84 receives this difference and determines the feedback high-voltage battery power modification value (P). bat_pwrmod ).

[0041] The energy management control system 50 determines the final high-voltage battery power requirement (P) at the battery comparator 92. bat_em_des ). The system-limited forward-coupling high-voltage battery power value (P bat_pwr_ff ) and the feedback high-voltage battery power modification value (P bar_pwrmod The values ​​are added together at summing junction 94. This sum is compared with the battery limits at battery comparator 92 to determine the final high-voltage battery power requirement value (P). bat_em_des ) to determine.

[0042] Fig. Figure 4 shows an enlarged view of the PI controller 84. The PI controller 84 receives the difference between the feedback high-voltage battery power demand (P) from the summing junction 90. bat_reqqpwrfb ) and the actual battery power (P bat_act The PI controller 84 has two parallel calculation methods. In the first method, the difference (P) is calculated. bat_reqpwrfb - P bat_act ) at the multiplication junction 95 is multiplied by a ratio constant (Kp). On the second path, the difference (P) bat _ reqpwrfb - P bat_act The value is multiplied by an integration constant (Ki) at the multiplication junction 96 and integrated at the integration block 97. The PI controller 84 then adds the values ​​from both paths at the summing junction 98 to determine the feedback high-voltage power modification value (P). bat_pwrmod ) to determine.

[0043] The calculations performed by the PI controller 84 to determine the feedback high-voltage battery power modification value (P bat_pwrmod ) to determine, are summarized by equation 1, as shown below: Pbat_pwrmod=(Pbat_reqpwrfb−Pbat_act)Kp+∫(Pbat_reqpwrfb−Pbat_act)Kidt

[0044] The forward feedback path of the energy management control system 50 is the main path, whereas the feedback loop 71 is optional and can be bypassed under certain operating conditions. Both constants (Kp) and (Ki) are calibratable and can be set to zero by the ECU 40. As shown by equation 1 above, (P bat_pwrmod) by setting the constants (Kp) and (Ki) to zero. The feedback loop 71 allows the energy management control system 50 to correct any differences between desired and actual values. If the ECU 40 determines that such differences are negligible, then the ECU 40 can set the constants (Kp) and (Ki) to zero in order to determine the final high-voltage battery power requirement (P). bat_en_des ) to simplify further.

[0045] The Fig. 5A-5C show a method 100 for the realization of the energy management control system 50 of the Fig. 2-4 according to one or more embodiments. The energy management control system 50 is part of the overall VSC 38 and is controlled by the ECU 40 according to one or more embodiments. Fig. 1. The ECU 40 generally has any number of microprocessors, ASICs, ICs, and memories (e.g., FLASH, ROM, RAM, EPROM, and / or EEPROM) that interact with software code to execute the steps of Procedure 100. Procedure 100 comprises eight determination blocks, each block containing a series of steps to determine a variable or value.

[0046] In step 102, the ECU receives 40 inputs from individual systems or sensors of the vehicle. The inputs include: the driver's torque request (T req_unf ), the mechanical transmission losses (T trans_loss ) , the system limits (T sys_min ,T sys_max ), the output shaft speed (ω oss ), the electrical system losses (P sys_loss ), the power state of charge conservation (PSOC), the motor speed (ω m ), the engine limits ( P eng_min ,P eng_max ), the battery limits (Pelec_chg_lim ,P elec_dch_lim ) and the actual battery power (P bat_act After receiving the input, the energy management control system 50 switches to block 104.

[0047] In block 104, the ECU 40 determines the driver power request (P drv_unf The sum of the driver torque request (T) req_unf ) and the mechanical transmission losses (T trans_loss ) is combined with the system limits ( T sys_min ,T sys_max ) compared. Then, based on the comparison, an equation is selected for calculating the driver performance requirement.

[0048] In step 106, the ECU 40 determines whether the sum of the driver torque request (T req_unf ) and the mechanical transmission losses (T trans_loss ) smaller than the minimum system torque (T sys_min ). If the determination in step 106 is positive, then the ECU 40 limits the torque to the minimum system torque (T). sys_min) and calculates the driver performance requirement (P) in step 108. drv_unf ) according to equation 2, as shown below: Pdrv_unf=(Tsys_min∗ωoss)+Psys_loss

[0049] If the determination in step 106 is negative, then ECU 40 proceeds to step 110. In step 110, ECU 40 determines whether the sum of the driver torque request (T) req_unf ) and the mechanical transmission losses (T trans_loss ) greater than the maximum system torque (T sys_max ). If the determination in step 110 is positive, then the ECU 40 limits the torque to the maximum system torque (T). sys_max ) and calculates the driver performance requirement (P) in step 112. drv_unf ) according to equation 3, as shown below: Pdrv_unf=(Tsys_max∗ωoss)+Psys_loss

[0050] If the determination in step 110 is negative, then the ECU 40 proceeds to step 114. In step 114, the ECU 40 calculates the driver power request (P). drv_unf ) according to equation 4, as shown below: Pdrv_unf=((Treq_unf+Ttrans_loss)∗ωoss)+Psys_loss

[0051] The ECU 40 switches to block 116 as soon as it receives the driver power request (P) in block 104. drv_unf ) has determined. In block 116, the ECU 40 determines the desired high-voltage battery power requirement (P). des_bat_pwrreq ) as a function of the driver's power demand (P drv_unf ), the power state of charge conservation (PSOC) and the motor speed (ω m After block 116, the energy management control system transitions to block 118.

[0052] In block 118, the ECU 40 determines the total power engine power requirement (P). eng_pwr_totFirst, the difference between the driver's power demand (P) is calculated. drv_unf ) and the desired high-voltage battery power requirement (P des_bat_pwvrreq ) with the engine limits (P eng_min ,P eng_max ) compared. Then, based on this comparison, an equation is used to calculate the total power requirement of the power machine (P). eng_pwr_tot ) selected.

[0053] In step 120, the ECU 40 determines whether the difference between the driver's power demand (P drv_unf ) and the desired high-voltage battery power requirement (P des_bat_pwrreq ) smaller than the minimum power output of the engine (P) eng_min ). If the determination in step 120 is positive, then in step 122 the ECU 40 limits the total engine power requirement to the minimum engine power (P). eng_pwr_tot = P eng_minIf the determination in step 120 is negative, then the ECU 40 proceeds to step 124. In step 124, the ECU 40 determines whether the difference between the driver's power demand (P) drv_unf ) and the desired high-voltage battery power requirement (P des_bat_pwrreq ) greater than the maximum power output of the engine (P) eng_max ). If the determination in step 124 is positive, then in step 126 the ECU 40 limits the total engine power requirement to the maximum engine power (P). eng_pwr_tot = P eng_max ).

[0054] If the determination in step 124 is negative, then the ECU 40 proceeds to step 128. In step 128, the ECU 40 calculates the total power requirement of the engine (P). eng_pwr_tot ) according to equation 5, as shown below: Peng_pwr_tot=Pdrv_unf−Pdes_bat_pwrreq

[0055] The ECU 40 switches to block 130 as soon as it has determined the total power requirement for the power units in block 118. In block 130, the ECU 40 determines the system-limited forward-coupling high-voltage battery power value (p). bat_pwr_ff The difference between the driver's power demand (P) drv_unf ) and the total power requirement of the power unit (P eng_pwr_tot ) is compared to the battery limits n (P elec_chg_lim ,P elec_dch_lim ) compared. Then, based on the comparison, an equation is used to calculate the system-limited forward-coupling high-voltage battery power value (P). bat_pwr_ff ) selected.

[0056] In step 132, the ECU 40 determines whether the difference between the driver's power demand (P drv_unf ) and the total power requirement of the power unit (P eng_pwr_tot ) smaller than the battery power charging limit (P elec_chg_lim). If the determination in step 132 is positive, then in step 134 the ECU 40 limits the system-limited forward coupling high-voltage battery power to the battery power charging limit (P). bat_pwr_ff = P elec_chg_lim If the determination in step 132 is negative, then the ECU 40 proceeds to step 136. In step 136, the ECU 40 determines whether the difference between the driver's power demand (P) drv_unf ) and the total power requirement of the power unit (P eng_pwr_tot ) greater than the battery power discharge limit (P elec_dch_lim ). If the determination in step 136 is positive, then in step 138 the ECU 40 limits the system-limited forward coupling high-voltage battery power to the battery power discharge limit (P). bat_pwr_ff = P elec_dch_lim ).

[0057] If the determination in step 136 is negative, then the ECU 40 proceeds to step 140. In step 140, the ECU 40 calculates the system-limited forward coupling high-voltage battery power (P). bat_pwr_ff ) according to equation 6, as shown below: Pbat_pwr_ff=Pdrv_unf−Peng_pwr_tot

[0058] The ECU 40 proceeds to step 141 as soon as it detects the system-limited forward coupling high-voltage battery power (P) in block 130. bat_pwr_ff ) has determined. In step 141, the ECU 40 determines whether the feedback loop 71 ( Fig. 3) is activated. In one or more embodiments, this determination is based on calibrated values ​​associated with the proportional constant (Kp) and the integration constant (Ki) of the PI controller 84 (as in Fig. (as shown in Figure 3). For example, if both constants (Kp and Ki) are equal to zero, then the feedback is not activated. However, if at least one of the constants is not equal to zero, then the feedback is activated. If the determination in step 141 is positive, then ECU 40 moves on to block 142.

[0059] In block 142, the ECU 40 determines the power engine power estimation (P). eng_pwr_est First, the function f(P) is defined. eng_pwr_tot ,τ eng , T eng_brk ω eng ), which is controlled by function block 74 ( Fig. 2) was determined, with the engine limits (P eng_min, P eng_max ) compared. Then, based on this comparison, an equation is used to calculate the power machine's power estimate (P). eng_pwr_est ) selected.

[0060] In step 144, the ECU 40 determines whether the function f(f(P) eng_pwr_tot ,τ eng ,T eng_brk ,ω eng ) smaller than the minimum power output of the engine (P)eng_min ). If the determination in step 144 is positive, then in step 146 the ECU 40 limits the power machine power estimation to the minimum power machine power (P). eng_pwr_est = P eng_min If the determination in step 144 is negative, then the ECU 40 proceeds to step 148. In step 148, the ECU 40 determines whether the function f(P eng_pwr_tot , τ eng ,T eng,brk ,ω eng ) greater than the maximum power output of the engine (P) eng_max ). If the determination in step 148 is positive, then the ECU 40 limits the power machine power estimation in step 150 to the maximum power machine power (P). eng_pwr_est = P eng_max ).

[0061] If the determination in step 148 is negative, then the ECU 40 proceeds to step 152. In step 152, the ECU 40 calculates the power machine performance estimate (P). eng_pwr_est) according to equation 7, as shown below: Peng_pwr_est=f(Peng_pwr_tot,τeng,Teng_brk,ωeng)

[0062] The ECU 40 switches to block 154 as soon as it receives the power engine power estimate (P) in block 142. eng_pwr_est ) calculated. In block 154, ECU 40 determines the driver performance estimate (P). drv ) based on the filtered driver torque request (T req First, the driver torque request (T) is determined. req_unf ) filtered by the weighted averaging filter 78 (as in Fig. 3 is shown). The sum of the filtered driver torque demand (T req ) and the mechanical transmission losses (T trans_loss ) is combined with the system limits (T sys_min ,T sys_max ) compared. Then, based on the comparison, an equation is used to calculate the driver performance estimate (P). eng_pwr_est ) selected.

[0063] In step 156, the ECU 40 determines whether the sum of the filtered driver torque request (T) req ) and the mechanical transmission losses (T trans_loss ) smaller than the minimum system torque (T sys_min If the determination in step 156 is positive, then the ECU 40 limits the torque to the minimum system torque and calculates the driver power estimate (P) in step 158. drv ) according to equation 8, as shown below: Pdrv=(Tsys_min∗ωoss)+Psys_loss

[0064] If the determination in step 156 is negative, then ECU 40 proceeds to step 160. In step 160, ECU 40 determines whether the sum of the filtered driver torque request (T) req ) and the mechanical transmission losses (T trans_loss ) greater than the maximum system torque (T sys_maxIf the determination in step 160 is positive, then the ECU 40 limits the torque to the maximum system torque and calculates the driver power estimate (P) in step 162. drv ) according to equation 9, as shown below: Pdrv=(Tsys_max∗ωoss)+Psys_loss

[0065] If the determination in step 160 is negative, then the ECU 40 proceeds to step 164. In step 164, the ECU 40 calculates the driver performance estimate (P). drv ) according to equation 10, as shown below: Pdrv=((Treq+Ttrans_loss)ωoss)+Psys_loss

[0066] The energy management control system moves to block 166 once it has determined the driver power estimate in block 154. In block 166, ECU 40 determines the feedback high-voltage battery power modification value (P). bat_pwr_mod The difference between the driver's power demand (P)drv_unf ) and the power machine power estimation (P eng_pwr_est ) is compared to the battery limits n (P elec_chg_lim ,P elec_dch_lim ) compared. Based on the comparison, an equation is used to calculate the feedback high-voltage battery power requirement (P). bat_reqpwrfb ) selected. Then the ECU 40 uses the PI controller 84 (as in Fig. 4 is shown), to determine the feedback high-voltage battery power modification value (P bat_pwrmod ) based on the feedback high-voltage battery power requirement (P bat_reqpwrfb to calculate.

[0067] In step 168, the ECU 40 determines whether the difference between the driver performance estimate (P drv_unf ) and the power machine power estimation (P eng_pwr_est ) smaller than the battery power charging limit (P elec_chg_lim). If the determination in step 168 is positive, then in step 170 the ECU 40 limits the feedback high-voltage battery power requirement to the battery power charging limit (P). bat_reqpwrfb = P elec_chg_lim If the determination in step 168 is negative, then the ECU 40 proceeds to step 172. In step 172, the ECU 40 determines whether the difference between the driver performance estimate (P) drv_unf ) and the power machine power estimation (P eng_pwr_est ) greater than the battery power discharge limit (P elec_dch_lim ). If the determination in step 172 is positive, then in step 174 the ECU 40 limits the feedback high-voltage battery power requirement to the battery power discharge limit (P). bat_reqpwrfb = P elec_dch_lim ).

[0068] If the determination in step 172 is negative, then the ECU 40 proceeds to step 176. In step 176, the ECU 40 calculates the feedback high-voltage battery power requirement (P). bat_reqpwrfb ) according to equation 11, as shown below: Pbat_reqpwrfb=Pdrv−Peng_pwr_est

[0069] The ECU 40 proceeds to step 178 as soon as it has determined the feedback high-voltage battery power requirement in step 170, 174, or 176. In step 178, the ECU 40 uses the PI controller 84 (as described in...). Fig. 3 and Fig. 4 is shown), to determine the feedback high-voltage battery power modification value (P bat_pwr_mod ) to be calculated according to equation 1, as shown above and reproduced below: Pbat_pwrmod=(Pbat_reqpwrfb−Pbat_act)Kp+∫(Pbat_reqpwrfb−Pbat_act)Kidt

[0070] The ECU 40 switches to block 180 as soon as it receives the feedback high-voltage battery power modification value (P) in block 166. bat_pwrmod ). Furthermore, if the determination in step 141 is negative, this feedback is not activated; the ECU 40 then proceeds to block 180, thus bypassing the feedback loop (blocks 142, 154, and 166). In block 180, the ECU 40 determines the final high-voltage battery power requirement (P). bat_em_des ).

[0071] In block 180, the sum of the system-limited forward-coupling high-voltage battery power (P) is calculated. bat_pwr_ff ) and the feedback high-voltage battery power modification value (P bat_pwr_mod ) with the battery limits n (P elec_chg_limelec_chg_lim ,P elec_dch_lim ) compared. Based on the comparison, an equation is used to calculate the final high-voltage battery power requirement (P). bat_em_des ) selected.

[0072] In step 182, the ECU 40 determines whether the sum of the system-limited forward coupling high-voltage battery power (P) bat_pwr_ff ) and the feedback high-voltage battery power modification value (P bar_pwr_mod ) smaller than the battery power charging limit (P elec_chg_lım ). If the determination in step 182 is positive, then in step 184 the ECU 40 limits the final high-voltage battery power requirement to the battery power charging limit (P). bat_em_des = P elec_chg_lim If the determination in step 182 is negative, then the ECU 40 proceeds to step 186. In step 186, the ECU 40 determines whether the sum of the system-limited forward coupling high-voltage battery power (P) bat_pwr_ff ) and the feedback high-voltage battery power modification value (P bat_pwr_mod ) greater than the battery power discharge limit (P elec_dch_lim). If the determination in step 186 is positive, then in step 188 the ECU 40 limits the final high-voltage battery power requirement to the battery power discharge limit (P). bat_em_des = P elec_dch_lim )

[0073] If the determination in step 186 is negative, then the ECU 40 proceeds to step 190. In step 190, the ECU 40 calculates the final high-voltage battery power requirement (P). bat_em_des ) according to equation 12, as shown below: Pbat_em_des=Pbat_pwr_ff+Pbat_pwr_mod

[0074] Therefore, different designs offer one or more advantages. For example, the energy management control system simplifies the vehicle's control logic. As with reference to Fig. As described in section 2, this simplification involves decoupling the speed and torque determinations into two independent control variables (GEAR_cmd and P).bat_em_des Furthermore, the determination of the high-voltage battery power requirement (P) bat_em_des ) can be further simplified by modifying the feedback loop 71 under certain operating conditions ( Fig. 3) is deactivated, as with reference to Fig. 3-5C is described.

Claims

[1] Method for controlling the energy distribution in a HEV powertrain, the method comprising: Generating a forward-coupling battery power value (P) bat_pwr_ff ) in response to the input, which is a driver torque request (T req_unf ) displays; Generating a feedback battery power modification value (P) bat_pwrmod ) in response to the input, which determines the actual battery power (P bat_act ) and the driver torque request (T req_unf ) displays; and Calculating a final high-voltage battery power requirement (P) bat_em_des ) based on a sum of the forward coupling battery power value (P bat_pwr_ff ) and the feedback battery power modification value (P bat_pwrmod ), characterized by Generating a power machine power estimate (P eng-pwr_est ) based on the power machine time delay (τ eng), of the engine braking torque (T eng_brk ) and the engine speed (ω eng ); Filtering the driver torque request (T req_unf ) using a filter (78) to obtain a filtered driver torque request (T req ) to generate; generating a driver performance estimate (P drv ) based on a product of the filtered driver torque demand (T req ) and a gearbox output shaft speed (ω oss ); where generating the feedback battery power modification value (P bat_pwrmod ) furthermore, a calculation of the feedback battery power modification value (P bat_pwrmod ) based on a difference between the driver performance estimate (P drv ) and the power machine power estimation (P eng_pwr_est ) includes. [2] Method according to claim 1, further comprising selectively disabling the feedback by adjusting the feedback power modification value (P bat_pwrmod ) is set to zero. [3] Method according to claim 1, further comprising: Receiving a transmission torque loss (T trans_loss ), which indicates mechanical efficiency losses; and Calculating a torque command (T cmd ) based on a system-limited sum of the driver torque request (T req_unf ) and the transmission torque loss (T trans_loss ). [4] The method of claim 3, further comprising: Receiving a system performance loss (P sys_loss ), which indicates electrical efficiency losses; and Generating a driver power request (P) drv_unf ) based on the system power loss (P sys_loss ), of the torque command (T cmd ) and the input, which is a gearbox output shaft speed (ω) oss) displays. [5] The method of claim 4, further comprising: Generating a power machine power demand (P) eng_pwr_tot ) based on a difference between the driver's power demand (P drv_unf ) and a desired high-voltage battery power requirement (P des_bat_pwrreq ); where generating the forward-coupling battery power value (P bat_pwr_ff ) furthermore, a calculation of the forward coupling battery power value (P bat_pwr_ff ) based on a difference between the driver's power demand (P drv_unf ) and the power engine power requirement (P eng_pwr_tot ) includes. [6] The method of claim 1, further comprising: Generating a wheel torque request in response to an input that specifies a regenerative torque value (T). regen ) and the driver torque request (T req_unf ) displays; and Comparing the wheel torque requirement with the final High-voltage battery power requirement (P bat_em_des ), to issue a power machine torque command (T cmd_eng ) and a motor torque command (T cmd_m to generate. [7] Energy management control system (50) with: a power engine control unit (40) which is configured to: Generating a driver power request (P) drv_unf ) based on a system-limited sum of a driver torque request (T req_unf ) and a transmission torque loss value (T trans_loss ), Generating a forward-coupling battery power value (P) bat_pwr_ff ) based on the driver performance request (P drv_unf ) and a power machine total power requirement (P eng_pwr_tot ) and Generating a final high-voltage battery power request (P bat_em_des ) in response to the forward-coupling battery power value (P bat_pwr_ff ), characterized by , that the engine control unit (40) is further equipped to: generate an engine power estimate (P eng-pwr_est ) based on the power machine time delay (τ eng ), of the engine braking torque (T eng_brk ) and the engine speed (ω eng ); Filtering the driver torque request (T req_unf ) using a filter (78) to obtain a filtered driver torque request (T req to generate; Generating a driver performance estimate (P drv ) based on a product of the filtered driver torque demand (T req ) and a gearbox output shaft speed (ω oss ); and where generating the feedback battery power modification value (P bat_pwrmod ) furthermore, a calculation of the feedback battery power modification value (P bat_pwrmod ) based on a difference between the driver performance estimate (P drv) and the power machine power estimation (P eng_pwr_est ) includes. [8] Energy management control system (50) according to claim 7, wherein the power engine control unit (40) is further configured to detect a desired high-voltage battery power demand (P des_bat_pwrreq ) based on an engine speed (ω oss ), a battery status (PSOC) and the driver power demand (P drv_ to generate unf). [9] Energy management control system (50) according to claim 8, wherein the total power machine power requirement (P eng_pwr_tot ) on a difference between the driver's power demand (P drv_unf ) and the desired high-voltage battery power requirement (P des_bat_pwrreq ) is based. [10] Energy management control system (50) according to claim 7, wherein the engine control unit (40) is further configured to: Receiving an input that provides a driver performance estimate (P drv) and a power machine power estimate (P eng_pwr_est ) displays, and Generating an output that includes a feedback battery power modification value (P) bat_pwrmod ) displays; Calculating the final high-voltage battery power requirement (P) bat_em_des ) based on a sum of the forward coupling battery power value (P bat_pwr_ff ) and the feedback battery power modification value (P bat_pwrmod ) [11] Energy management control system (50) according to claim 10, wherein the power machine control unit (40) is further configured to selectively deactivate the feedback by adjusting the feedback battery power modification value (P bat_pwrmod ) is set to zero. [12] Energy management control system (50) according to claim 7, wherein the engine control unit (40) is further configured to estimate the engine power (P eng_pwr_est ) based on the total power requirement of the power unit (Peng_pwr_tot ) and generate an input which determines the power machine time delay (τ eng ), the engine braking torque (T eng_brk ) and the engine speed (ω eng ) displays. [13] Hybrid electric vehicle (10) with: an energy management control system (50) configured to generate an output that enables gear selection in response to a transmission input speed (ω) in ) displays; and a power engine control unit (40) that communicates with the energy management control system (50) and is set up to generate an output in response to an input that is a driver torque request (T req_unf ) and actual battery power (P bat_act ) displays, and regardless of gear selection, a power engine torque command (T) cmd_eng ) and a motor torque command (T cmd_m ) displays, characterized by , that the engine control unit (40) is further configured to: Generating a power machine power estimate (P eng-pwr_est ) based on the power machine time delay (τ eng ), of the engine braking torque (T eng_brk ) and the engine speed (ω eng ); Filtering the driver torque request (T req_unf ) using a filter (78) to obtain a filtered driver torque request (T req to generate; Generating a driver performance estimate (P drv ) based on a product of the filtered driver torque demand (T req ) and a gearbox output shaft speed (ω oss ); and where generating the feedback battery power modification value (P bat_pwrmod ) furthermore, a calculation of the feedback battery power modification value (P bat_pwrmod ) based on a difference between the driver performance estimate (Pdrv ) and the power machine power estimation (P eng_pwr_est ) includes. [14] Hybrid electric vehicle (10) according to claim 13, further comprising: a motor (14) having a motor output shaft extending from it, wherein the motor (14) communicates with the control unit (40) and generates a motor torque in response to the motor torque command (T cmd_m ) provides; and a transmission (16) having a transmission input shaft suitable for selectively engaging the motor output shaft to receive the motor torque, wherein the transmission (16) is coupled to at least two drive wheels (24) to transmit the motor torque to the drive wheels (24) for driving the vehicle (10). [15] Hybrid electric vehicle (10) according to claim 14, further comprising: a power machine (12) having a power machine output shaft extending from it, wherein the power machine (12) communicates with the power machine control unit (40) and a power machine torque is generated in response to the power machine torque command (T cmd_eng ) provides; wherein the motor (14) further comprises an input shaft which is suitable for selectively engaging the power machine output shaft, and wherein the motor (14) is configured to supply the transmission (16) with the motor torque and the total power machine torque. [16] Hybrid electric vehicle (10) according to claim 13, wherein the engine control unit (40) is further configured to: Generating a final high-voltage battery power request (P bat_em_des ) in response to the driver's torque request (T req_unf ) and the actual battery power (P bat_act ); Generating the output that represents the power machine torque command (T cmd_eng ) and the motor torque command (T cmd_m ) in response to the final high-voltage battery power requirement (P bat_ein_des ) displays. [17] Hybrid electric vehicle (10) according to claim 16, wherein the engine control unit (40) is further configured to: Generating a forward-coupling battery power value (P) bat_pwr_ff ) in response to the driver's torque request (T req_unf ); Generating a feedback battery power modification value (P) bat_pwrmod ) in response to the driver's torque request (T req_unf ) and the actual battery power (P bat_act ) ; and Calculating the final high-voltage battery power requirement (P) bat_em_des ) based on a sum of the forward coupling battery power value (P bat_pwr_ff ) and the feedback battery power modification value (P bat_pwrmod ) [18] Hybrid electric vehicle (10) according to claim 13, wherein the driver torque request (T req_unf ) indicates an accelerator pedal position and where the actual battery power (P bat_act ) indicates a battery voltage measurement and a battery current measurement.

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