Dynamic energy management and control system and method for power transmission system of heavy-duty commercial vehicle

Abstract

The invention discloses a dynamic management and control system and method for energy of a power transmission system of a heavy commercial vehicle, and belongs to the technical field of energy recovery of heavy trucks, and the dynamic management and control system comprises a power takeoff which is used for extracting rotary power from a gear train of a transmission as required and providing mechanical energy input for a generator; the electromagnetic valve is used for receiving the electric signal instruction of the control unit and driving the clutch action of the power takeoff by controlling a gas circuit, so that the power takeoff is connected with or separated from a power output gear of the transmission; the generator converts the mechanical energy input by the power takeoff into electric energy and sends the electric energy to the energy storage device; and the control unit is used for acquiring state parameters of the heavy commercial vehicle in real time, judging the current operation condition of the vehicle and the intention of a driver based on the state parameters, and generating a decision instruction based on the operation condition and the intention of the driver. The defects that in the prior art, the energy recovery function and the auxiliary braking function are separated, efficiency is not high, and control is not precise are successfully overcome.

Description

Technical Field

[0001] This invention belongs to the field of heavy-duty truck energy recovery technology, specifically relating to a dynamic energy management system and method for the powertrain of heavy-duty commercial vehicles. Background Technology

[0002] Heavy-duty trucks, due to their large load capacity and high operational intensity, face extremely stringent requirements for driving safety and fuel economy. Their braking systems typically comprise a service braking system (main brake) and an auxiliary braking system. The main braking system primarily generates braking force through friction between the friction pads and the brake drum / disc, converting the vehicle's kinetic energy into heat energy and dissipating it. The auxiliary braking system, on the other hand, shares the load with the main braking system; common types include engine braking, exhaust braking, hydraulic retarders, and eddy current retarders.

[0003] Meanwhile, vehicle energy recovery technologies, particularly in hybrid and electric vehicles, have been extensively researched and applied. These technologies typically convert some of the kinetic or potential energy into electrical energy via a generator during vehicle deceleration or braking, storing it in batteries or other energy storage devices. In the heavy-duty truck sector, there have also been attempts to utilize the engine for energy recovery or to configure a separate generator for energy recovery.

[0004] A power take-off (PTO) is a common accessory on truck transmissions. It extracts power from the transmission to drive various auxiliary equipment, such as hydraulic pumps and air compressors. Using a PTO to drive a generator is also a known technological approach.

[0005] The technical solutions most similar to this invention are mainly:

[0006] Independent electric retarder / generator system: In this type of solution, the vehicle is equipped with an eddy current retarder or a dedicated generator system to provide auxiliary braking force. Some advanced electric retarders also have a certain power generation capability, which can recover some braking energy. For example, some eddy current retarders generate a reverse torque to assist braking by cutting magnetic field lines when they are working, and the current generated in their coils can be partially converted into electrical energy.

[0007] Structural components: It typically includes the retarder body (stator coils, rotor disc), controller, and possibly energy recovery circuitry and energy storage devices. The retarder is usually mounted on the drive shaft.

[0008] Operating principle: After the driver activates the retarder, the controller adjusts the excitation current in the stator coil to generate a magnetic field. The rotor disk rotates in the magnetic field, cutting magnetic lines of force to create braking torque. If energy recovery is available, the generated electrical energy will be converted and used to charge the battery.

[0009] Disadvantages: While these systems can provide assisted braking and some energy recovery, their generators / retarders are typically optimized for braking, potentially limiting energy recovery efficiency and control flexibility. Integration with the PTO (Power Transfer Unit) is not tight enough, or the PTO is not fully utilized in the integrated design. Their control strategies may not be deeply coordinated with the vehicle's overall energy management.

[0010] The aforementioned existing technical solutions focus on auxiliary braking while energy recovery is secondary and the control is not precise enough. They fail to achieve a high degree of integration and intelligent collaborative control between the efficient energy recovery of PTO drive and the precisely adjustable auxiliary braking function.

[0011] The disadvantages of existing technologies include:

[0012] 1. Limited and incomplete energy recovery efficiency: In existing solutions, if traditional friction braking is used, energy is wasted entirely as heat (disadvantage: low energy utilization). If an electric retarder is used, its design may prioritize braking torque over power generation efficiency, resulting in the energy recovery potential not being fully explored (disadvantage: low energy recovery efficiency). If only simple PTO power generation is used, the recovery conditions are limited and cannot cover major energy recovery scenarios such as deceleration and braking (disadvantage: insufficient utilization of energy recovery opportunities).

[0013] 2. Insufficient auxiliary braking capability and control precision: Simple PTO power generation schemes provide almost no meaningful auxiliary braking (disadvantage: lack of effective auxiliary braking means). Although electric retarders can provide auxiliary braking, their control may not be smooth enough, their response speed has room for improvement, and their coordination with the overall vehicle status (such as linkage with the anti-lock braking system ABS) may not be deep enough (disadvantage: insufficient auxiliary braking control precision and intelligence).

[0014] 3. Poor system integration and coordination: If the energy recovery module and auxiliary braking module are separate or loosely coupled, it will lead to a more complex system assembly, increased weight, and higher cost (disadvantages: low system integration, higher cost). More importantly, the lack of a unified intelligent control unit to efficiently coordinate the two makes it difficult to achieve the optimal balance between energy recovery and auxiliary braking under complex operating conditions (disadvantages: lack of multi-functional collaborative control, limited overall performance). For example, the optimal time for energy recovery is when strong auxiliary braking is needed, but a separate system cannot perfectly coordinate the needs of both.

[0015] 4. High dependence on the main braking system: Due to the above-mentioned disadvantages, energy recovery is insufficient and the auxiliary braking effect is not optimal. The driver still needs to use the main braking system frequently, which accelerates the wear of brake pads / discs, increases the risk of heat fade, and shortens the maintenance cycle (disadvantages: the main braking system wears quickly, maintenance costs are high, and potential safety risks increase). Summary of the Invention

[0016] The purpose of this invention is to provide a dynamic energy management system and method for the powertrain of heavy commercial vehicles, aiming to solve at least one of the above-mentioned problems and defects in the prior art.

[0017] To achieve the above objectives, the present invention provides the following technical solution:

[0018] The first objective of this invention is to provide a dynamic energy management system for the powertrain of a heavy-duty commercial vehicle, comprising:

[0019] The power take-off (PTO) extracts rotational power from the gear train of the transmission as needed to provide mechanical energy input to the generator;

[0020] The solenoid valve receives electrical signal commands from the control unit and drives the clutch action of the power take-off by controlling the air circuit, thereby realizing the engagement or disengagement of the power take-off and the power output gear of the transmission.

[0021] The generator converts the mechanical energy input from the power take-off unit into electrical energy and sends it to the energy storage device;

[0022] The control unit acquires the status parameters of the heavy commercial vehicle in real time, determines the current operating condition of the vehicle and the driver's intention based on the status parameters, and generates decision instructions based on the operating condition and the driver's intention.

[0023] Preferably, the status parameters include one or more of the following: vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, anti-lock braking system (ABS) status, gear information, energy storage device state of charge, and temperature.

[0024] Preferably, the operating conditions include one or more of acceleration, constant speed, coasting, deceleration, braking, uphill, and downhill.

[0025] Preferably, the generator includes:

[0026] In power generation mode, the mechanical energy input from the power take-off unit is converted into three-phase alternating current;

[0027] In the auxiliary braking mode, the excitation current or equivalent magnetic field strength is controlled by the control unit to generate an electromagnetic torque that is opposite to the direction of wheel rotation. This electromagnetic torque is transmitted to the wheels through the power take-off and transmission to form an auxiliary braking force. At this time, the generator is still in the power generation state, forcibly converting the vehicle's kinetic / potential energy into electrical energy.

[0028] Preferably, the generator includes:

[0029] Adjustable excitation systems, for hybrid excitation or electrically excitation synchronous generators containing excitation windings, allow the control unit to change the strength of the main magnetic field inside the generator by controlling the magnitude of the DC current supplied to the excitation windings. For permanent magnet synchronous generators, the control unit indirectly affects the air gap magnetic field and output torque / voltage by controlling the phase and amplitude of the stator current.

[0030] Pulse width modulation (PWM) is a power drive module that is integrated internally or externally connected to the control unit. According to the instructions of the control unit, it adjusts the average current value supplied to the generator excitation winding or controls the stator phase current. By adjusting the duty cycle of the PWM signal, it controls the generator magnetic field strength, output voltage or braking torque.

[0031] Preferably, the control unit includes:

[0032] The data acquisition and processing module acquires vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, anti-lock braking system (ABS) status, gear information, energy storage device charge status, and temperature in real time via the vehicle bus.

[0033] The decision-making logic and mode switching module intelligently determines the vehicle's current operating condition and the driver's intentions based on collected multi-source information, and decides which operating mode the system should be in:

[0034] In standby mode, when neither energy recovery nor auxiliary braking is required, the control unit controls the solenoid valve to disconnect the power take-off unit from the transmission, and the generator does not work.

[0035] In energy recovery mode, when the vehicle deceleration, braking, or downhill coasting is detected, the control unit controls the solenoid valve to engage the power take-off and drive the generator to work; at the same time, the control unit controls the excitation of the generator through PWM according to the vehicle speed, SOC, and energy recovery potential.

[0036] In assisted braking mode, when the driver has a clear need for assisted braking, the control unit controls the power take-off to engage and increases the excitation of the generator to obtain reverse braking torque. In this mode, energy recovery still takes place.

[0037] In the control signal output mode, a switching signal is output to the solenoid valve to control the on / off state of the power take-off unit; a PWM control signal is output to the generator's excitation system to adjust the generator's magnetic field strength / output torque.

[0038] Preferably, the generator adopts a multi-pole permanent magnet synchronous or hybrid excitation synchronous structure.

[0039] The second objective of this invention is to provide a method for dynamic energy management of the powertrain of heavy-duty commercial vehicles, including the following operating mode judgment and switching process:

[0040] Real-time acquisition of vehicle status information;

[0041] Based on the aforementioned status information, determine whether the triggering conditions for the energy recovery mode are met;

[0042] When the status information determines that the triggering conditions for the energy recovery mode are met, the energy recovery mode is entered. First, the solenoid valve is controlled to engage the power take-off unit to adjust the excitation of the generator. Then, the SOC, vehicle speed and driver operation commands are monitored in real time to adjust the excitation intensity. The status information is checked again to determine whether the triggering conditions for the energy recovery mode are met. If so, the steps of entering the energy recovery mode are repeated. Otherwise, the energy recovery mode is exited.

[0043] When the status information indicates that the triggering conditions for the energy recovery mode are not met, it is determined whether the conditions for the auxiliary braking mode are met. If the conditions for the auxiliary braking mode are met, the auxiliary braking mode is entered, and the solenoid valve is controlled to engage the power take-off to enhance the excitation of the generator. If the conditions for the auxiliary braking mode are not met, the power take-off remains disengaged.

[0044] A third objective of this invention is to provide a method for dynamic energy management of the powertrain of heavy-duty commercial vehicles, comprising the following energy recovery control process:

[0045] Real-time acquisition of vehicle status information;

[0046] Based on the status information, determine whether the energy recovery start-up conditions are met;

[0047] When the status information determines that the energy recovery start-up conditions are met, the solenoid valve is first controlled to engage the power take-off unit to start the generator. Then, the target excitation intensity is determined according to the real-time operating conditions, and the closed-loop control PWM signal is output to the generator's excitation system.

[0048] If the status information indicates that the energy recovery start-up conditions are not met, monitoring will continue.

[0049] The fourth objective of this invention is to provide a method for dynamic energy management of the powertrain of a heavy-duty commercial vehicle, comprising the following auxiliary braking control process:

[0050] Real-time acquisition of vehicle status information;

[0051] Based on the status information, determine whether the auxiliary braking triggering condition is met;

[0052] When the status information determines that the auxiliary braking triggering condition is met, the power take-off is first engaged and the generator is started. Then, the target braking torque is calculated based on the intensity of the auxiliary braking request, the current vehicle speed, and the state of charge (SOC). Subsequently, the calculation results are converted into the target excitation current and the target PWM duty cycle. Finally, the generator excitation current is adjusted using PWM to apply the reverse electromagnetic braking torque.

[0053] If the status information indicates that the auxiliary braking triggering conditions are not met, monitoring continues.

[0054] Compared with the prior art, the beneficial effects of the present invention are:

[0055] This invention successfully overcomes the shortcomings of existing technologies, such as the separation of energy recovery and auxiliary braking functions, low efficiency, and imprecise control, by organically integrating key components such as the power take-off-driven generator, intelligent control unit, and energy storage device into a highly coordinated system. Its main advantages are:

[0056] First, by employing a control strategy and precisely adjusting the generator's operating mode, this invention enables efficient energy recovery under various complex operating conditions such as vehicle deceleration, braking, and downhill driving. This significantly improves energy utilization, directly addressing the problem of low energy recovery efficiency in existing technologies, and also helps to significantly reduce fuel consumption, thereby enhancing the overall economy of the vehicle.

[0057] Secondly, the powerful and precisely adjustable auxiliary braking torque provided by the generator effectively reduces the load on the main braking system. This feature not only reduces wear and thermal fade risks in the main braking system but also significantly improves braking safety and reliability under dangerous conditions such as long downhill slopes. This improvement directly addresses the problems of heavy load on the main braking system and insufficient auxiliary braking capacity, further enhancing vehicle safety performance.

[0058] Furthermore, this invention enables seamless switching and coordinated optimization of energy recovery and assisted braking functions through unified intelligent scheduling of the ECU, based on actual needs. This design avoids the complexity and potential conflicts associated with separate systems, thereby addressing the issues of poor system integration and coordination, and improving the overall operating efficiency and stability of the system.

[0059] Ultimately, this invention not only significantly improves vehicle economy and safety, but also effectively enhances driving comfort through a smoother and smarter assisted braking experience. This comprehensive improvement enables the invention to demonstrate superior performance advantages in vehicle applications, providing drivers with a safer, more economical, and more comfortable driving experience. Attached Figure Description

[0060] Figure 1 This is a system block diagram of a preferred embodiment of the present invention;

[0061] Figure 2 This is a flowchart of the system working mode determination and switching in a preferred embodiment of the present invention;

[0062] Figure 3 This is a flowchart of the energy recovery control in a preferred embodiment of the present invention;

[0063] Figure 4This is a flowchart of the auxiliary braking control in a preferred embodiment of the present invention. Detailed Implementation

[0064] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0065] Please see Figure 1 A dynamic energy management system for the powertrain of a heavy-duty commercial vehicle, comprising:

[0066] The power take-off (PTO) extracts rotational power from the gear train of the transmission as needed to provide mechanical energy input to the generator;

[0067] The power take-off (PTO) is mounted on the transmission housing of a heavy-duty truck. Its main function is to precisely extract rotational power from the complex gear system of the transmission according to actual needs. This extracted power is then used to provide the essential mechanical energy input to the generator, ensuring its normal operation. Specifically, the PTO's output shaft and the generator's input shaft are efficiently connected via a transmission mechanism. These mechanisms may include various forms such as universal joint driveshafts or direct gear connections (not shown in detail in the diagram), ensuring the stability and efficiency of power transmission.

[0068] The solenoid valve receives electrical signal commands from the control unit and drives the clutch action of the power take-off by controlling the air circuit, thereby realizing the engagement or disengagement of the power take-off and the power output gear of the transmission.

[0069] The primary function of the solenoid valve in the system is to precisely control the engagement and disengagement of the PTO (Power Take-Off) gear. Specifically, the solenoid valve receives electrical signal commands from the control unit (ECU), which are automatically generated by the system based on the current operating status and requirements. Upon receiving the command, the solenoid valve adjusts the opening and closing of the air passage, thereby driving the clutch mechanism inside the PTO to perform corresponding actions. The ultimate goal of this series of actions is to achieve precise engagement or complete disengagement between the PTO and the transmission's power output gear, ensuring the stability and reliability of power transmission and meeting operational requirements under different conditions.

[0070] The generator converts the mechanical energy input from the power take-off unit into electrical energy and sends it to the energy storage device;

[0071] The generator in this invention has the following characteristics:

[0072] The generator is driven by a PTO. A permanent magnet synchronous generator or a hybrid excitation synchronous generator is preferred because of its high efficiency, high power density and good speed regulation performance.

[0073] The generator can employ an 8-pole permanent magnet rotor structure to obtain suitable output voltage and frequency at relatively low speeds. The stator uses optimized slot configuration and winding distribution to reduce harmonics, increase sinusoidal frequency, and increase fundamental inductance, thereby improving the generator's electrical performance and output characteristics.

[0074] The generator has a dual-mode function: it is designed to operate efficiently in generator mode and provide controllable braking torque in auxiliary braking mode.

[0075] Power generation mode: Converts the mechanical energy input from the PTO into three-phase alternating current.

[0076] Assisted braking mode: The ECU controls the excitation current or equivalent magnetic field strength to generate an electromagnetic torque opposite to the direction of wheel rotation. This torque is transmitted to the wheels through the PTO and transmission, forming an auxiliary braking force. At this time, the generator is still generating electricity, forcibly converting the vehicle's kinetic / potential energy into electrical energy.

[0077] Adjustable Excitation System: For hybrid or electrically excited synchronous generators, an excitation winding is internally included. The ECU precisely controls the magnitude of the DC current (excitation current) supplied to the excitation winding to change the strength of the main magnetic field inside the generator. For permanent magnet synchronous generators, although the main magnetic field is generated by permanent magnets, the air gap magnetic field and output torque / voltage can still be indirectly affected by controlling the phase and amplitude of the stator current (such as the d-axis current in a vector control strategy). Alternatively, when a wider speed range or strong magnetic braking is required, a field weakening control or a dedicated braking excitation winding can be added. In this scheme, it mainly refers to adjusting the magnetic field strength by controlling the current of the electromagnet.

[0078] Pulse Width Modulation (PWM) Precision Regulation: The ECU integrates or connects an external power drive module (such as an H-bridge circuit or part of a three-phase inverter). This module uses pulse width modulation (PWM) technology to precisely adjust the average current value supplied to the generator's excitation winding (for electric excitation) or control the stator phase current (for vector control of permanent magnet synchronous motors) according to the ECU's instructions. By adjusting the duty cycle of the PWM signal, rapid, smooth, and precise control of the generator's magnetic field strength, and consequently its output voltage (generator mode) or braking torque (braking mode), is achieved.

[0079] The ECU obtains vehicle status parameters (such as vehicle speed and target braking force) from the vehicle bus and compares them with set values. It calculates the control deviation using a built-in control algorithm and dynamically adjusts the PWM output to form a closed-loop control of the generator excitation or stator current, ensuring that the actual power generation or braking torque accurately tracks the target command.

[0080] The control unit acquires the status parameters of the heavy commercial vehicle in real time, determines the current operating condition of the vehicle and the driver's intention based on the status parameters, and generates decision instructions based on the operating condition and the driver's intention.

[0081] The control unit (ECU) is typically a microcontroller-based electronic control unit, and its main functions include:

[0082] Data acquisition and processing module: Real-time acquisition of vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, ABS status, gear information, state of charge (SOC) of energy storage device, temperature, etc. via vehicle bus (usually CAN bus).

[0083] Decision-making logic and mode switching: The system incorporates sophisticated control strategies and algorithms. Based on multi-source information, it intelligently determines the vehicle's current operating condition (e.g., acceleration, constant speed, coasting, deceleration, braking, uphill, downhill, etc.) and the driver's intentions, deciding which operating mode the system should operate in.

[0084] Standby mode: When energy recovery and auxiliary braking are not required (such as when the vehicle is accelerating or climbing hills with heavy throttle), the ECU controls the solenoid valve to disconnect the PTO from the transmission, and the generator does not work to reduce unnecessary drag losses.

[0085] Energy recovery mode (generation mode): When vehicle deceleration, braking (light to moderate), or downhill coasting is detected, the ECU controls the solenoid valve to engage the PTO, driving the generator. At the same time, the ECU controls the generator excitation (or equivalent control) through PWM based on factors such as vehicle speed, SOC, and energy recovery potential to recover energy with optimal efficiency.

[0086] Assisted braking mode: When the ECU detects a clear driver need for assisted braking (such as pressing the brake pedal beyond a certain threshold, activating the assisted braking switch, or the ECU determining that active speed control is needed on a long downhill slope), the ECU controls the PTO to engage (if it is not already engaged) and significantly increases the generator excitation (or equivalent control) to generate strong reverse braking torque. Energy recovery continues in this mode.

[0087] Control signal output: Outputs a switching signal to the solenoid valve to control the on / off state of the PTO; outputs a PWM control signal to the generator's excitation system (or its driver) to adjust the generator's magnetic field strength / output torque.

[0088] Communication and Coordination: The system interacts with other vehicle control systems (such as the Vehicle Control Unit (VCU), Engine Management System (EMS), ABS, and Battery Management System (BMS)) via the CAN bus for information exchange and functional coordination. For example, when ABS is activated, it may actively reduce or temporarily cancel auxiliary braking force to prevent wheel lock-up and ensure steering capability.

[0089] In the above embodiments, the state parameters include one or more of the following: vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, anti-lock braking system (ABS) status, gear information, energy storage device state of charge, and temperature.

[0090] The operating conditions include one or more of the following: acceleration, constant speed, coasting, deceleration, braking, uphill, and downhill.

[0091] The generator includes at least:

[0092] In power generation mode, the mechanical energy input from the power take-off unit is converted into three-phase alternating current;

[0093] In the auxiliary braking mode, the excitation current or equivalent magnetic field strength is controlled by the control unit to generate an electromagnetic torque that is opposite to the direction of wheel rotation. This electromagnetic torque is transmitted to the wheels through the power take-off and transmission to form an auxiliary braking force. At this time, the generator is still in the power generation state, forcibly converting the vehicle's kinetic / potential energy into electrical energy.

[0094] The generator may further include:

[0095] Adjustable excitation systems, for hybrid excitation or electrically excitation synchronous generators containing excitation windings, allow the control unit to change the strength of the main magnetic field inside the generator by controlling the magnitude of the DC current supplied to the excitation windings. For permanent magnet synchronous generators, the control unit indirectly affects the air gap magnetic field and output torque / voltage by controlling the phase and amplitude of the stator current.

[0096] Pulse width modulation (PWM) is a power drive module that is integrated internally or externally connected to the control unit. According to the instructions of the control unit, it adjusts the average current value supplied to the generator excitation winding or controls the stator phase current. By adjusting the duty cycle of the PWM signal, it controls the generator magnetic field strength, output voltage or braking torque.

[0097] The control unit includes:

[0098] The data acquisition and processing module acquires vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, anti-lock braking system (ABS) status, gear information, energy storage device charge status, and temperature in real time via the vehicle bus.

[0099] The decision-making logic and mode switching module intelligently determines the vehicle's current operating condition and the driver's intentions based on collected multi-source information, and decides which operating mode the system should be in:

[0100] In standby mode, when neither energy recovery nor auxiliary braking is required, the control unit controls the solenoid valve to disconnect the power take-off unit from the transmission, and the generator does not work.

[0101] In energy recovery mode, when the vehicle deceleration, braking, or downhill coasting is detected, the control unit controls the solenoid valve to engage the power take-off and drive the generator to work; at the same time, the control unit controls the excitation of the generator through PWM according to the vehicle speed, SOC, and energy recovery potential.

[0102] In assisted braking mode, when the driver has a clear need for assisted braking, the control unit controls the power take-off to engage and increases the excitation of the generator to obtain reverse braking torque. In this mode, energy recovery still takes place.

[0103] In the control signal output mode, a switching signal is output to the solenoid valve to control the on / off state of the power take-off unit; a PWM control signal is output to the generator's excitation system to adjust the generator's magnetic field strength / output torque.

[0104] The generator adopts a multi-pole permanent magnet synchronous or hybrid excitation synchronous structure.

[0105] Energy storage devices are used to store electrical energy recovered by generators.

[0106] Energy storage devices can be high-power lithium-ion battery packs. The selection criteria are mainly energy density, power density, cycle life, cost, and safety. Supercapacitors have faster charge and discharge rates and longer cycle life, making them suitable for frequent, short-term high-power recovery and release; power batteries have higher energy density and are suitable for storing more electrical energy.

[0107] Energy storage devices must be equipped with a Battery Management System (BMS). The BMS is responsible for monitoring the battery's voltage, current, temperature, state of charge (SOC), and state of health (SOH), and performing equalization control, charge and discharge protection, thermal management, etc., to ensure the safe, efficient, and long-life operation of the energy storage device. The BMS also communicates with the ECU via a CAN bus.

[0108] The electrical energy stored in energy storage devices can be used for:

[0109] Electrical accessories that drive the vehicle (such as air conditioning compressor, electric power steering pump, lighting, etc.);

[0110] Provides electrical power when the engine starts or idles.

[0111] The vehicle bus is typically a CAN (Controller Area Network) bus, which serves as a communication network for the ECU to exchange data with other electronic control units in the vehicle.

[0112] The present invention utilizes a specially designed generator driven by a single power take-off (PTO) with an adjustable excitation system, which is controlled by an intelligent control unit (ECU) to switch and operate between a high-efficiency power generation mode and a precisely adjustable auxiliary braking mode.

[0113] The generator in this invention adopts a multi-pole permanent magnet synchronous or hybrid excitation synchronous structure, and combines optimized stator slot type and winding design to adapt to PTO drive characteristics and take into account power generation efficiency and braking torque output capability.

[0114] The control unit (ECU) in this invention adopts a closed-loop control strategy based on pulse width modulation (PWM) (such as PID control) to achieve dynamic, fast and precise control of power generation and auxiliary braking torque by precisely adjusting the excitation current (or equivalent magnetic field control parameters) of the generator.

[0115] The control unit (ECU) in this invention can intelligently judge the operating conditions and automatically decide on the engagement / disengagement of the PTO and the working mode and parameters of the generator based on various real-time collected vehicle operating parameters (such as vehicle speed, throttle, brake pedal status, slope, energy storage device SOC, etc.) and driver commands.

[0116] The present invention has an auxiliary braking mode in which the system can achieve multi-level adjustable braking torque output, has an emergency braking enhancement function, and can work in conjunction with the vehicle's anti-lock braking system (ABS).

[0117] The present invention features an energy recovery mode in which the system can adaptively adjust the excitation intensity of the generator according to real-time operating conditions (such as vehicle speed and SOC) to optimize energy recovery efficiency, and optionally combine predictive control strategies (based on navigation or driving behavior data) to further improve the energy recovery effect.

[0118] This invention enables deep information interaction and collaborative control with other vehicle control systems (such as engine management system EMS, vehicle control unit VCU, anti-lock braking system ABS, and battery management system BMS) via CAN bus, thereby achieving energy optimization management and braking performance improvement at the vehicle level.

[0119] The energy storage device (such as a lithium battery pack or a supercapacitor pack) in this invention, in conjunction with the generator and ECU, is not only used to store the recovered energy, but its state (such as SOC, temperature) also serves as an important input for the ECU control strategy.

[0120] Please see Figure 2 A method for dynamic energy management of the powertrain of heavy-duty commercial vehicles, comprising the following working mode judgment and switching process:

[0121] Real-time acquisition of vehicle status information;

[0122] Based on the aforementioned status information, determine whether the triggering conditions for the energy recovery mode are met;

[0123] When the status information determines that the triggering conditions for the energy recovery mode are met, the energy recovery mode is entered. First, the solenoid valve is controlled to engage the power take-off unit to adjust the excitation of the generator. Then, the SOC, vehicle speed and driver operation commands are monitored in real time to adjust the excitation intensity. The status information is checked again to determine whether the triggering conditions for the energy recovery mode are met. If so, the steps of entering the energy recovery mode are repeated. Otherwise, the energy recovery mode is exited.

[0124] When the status information indicates that the triggering conditions for the energy recovery mode are not met, it is determined whether the conditions for the auxiliary braking mode are met. If the conditions for the auxiliary braking mode are met, the auxiliary braking mode is entered, and the solenoid valve is controlled to engage the power take-off to enhance the excitation of the generator. If the conditions for the auxiliary braking mode are not met, the power take-off remains disengaged.

[0125] Please see Figure 3 A method for dynamic energy management of the powertrain of a heavy-duty commercial vehicle, comprising the following energy recovery control process:

[0126] Real-time acquisition of vehicle status information;

[0127] Based on the status information, determine whether the energy recovery start-up conditions are met;

[0128] When the status information determines that the energy recovery start-up conditions are met, the solenoid valve is first controlled to engage the power take-off unit to start the generator. Then, the target excitation intensity is determined according to the real-time operating conditions, and the closed-loop control PWM signal is output to the generator's excitation system.

[0129] If the status information indicates that the energy recovery start-up conditions are not met, monitoring will continue.

[0130] Please see Figure 4 A method for dynamic energy management of the powertrain of a heavy-duty commercial vehicle, comprising the following auxiliary braking control procedures:

[0131] Real-time acquisition of vehicle status information;

[0132] Based on the status information, determine whether the auxiliary braking triggering condition is met;

[0133] When the status information determines that the auxiliary braking triggering condition is met, the power take-off is first engaged and the generator is started. Then, the target braking torque is calculated based on the intensity of the auxiliary braking request, the current vehicle speed, and the state of charge (SOC). Subsequently, the calculation results are converted into the target excitation current and the target PWM duty cycle. Finally, the generator excitation current is adjusted using PWM to apply the reverse electromagnetic braking torque.

[0134] If the status information indicates that the auxiliary braking triggering conditions are not met, monitoring continues.

[0135] The principles of use of this invention include:

[0136] System initialization and standby:

[0137] After the vehicle starts, the ECU performs a self-check and initialization. Under conditions where energy recovery or auxiliary braking is not required, such as normal vehicle acceleration or high engine load output (e.g., climbing a hill), the ECU controls the solenoid valve to keep the PTO disengaged, the alternator does not work, and the system is in standby mode to reduce the additional load on the engine.

[0138] Triggering and control of energy recovery mode:

[0139] Trigger condition determination: The ECU continuously monitors whether one or more of the following combined conditions are met:

[0140] When the driver releases the accelerator pedal, the vehicle is in a coasting state.

[0141] The driver lightly to moderately presses the brake pedal.

[0142] When a vehicle is driving downhill, it can be determined by GPS information, slope sensors, or by estimation based on vehicle speed and engine torque / throttle opening.

[0143] The SOC of the energy storage device is lower than a preset higher threshold (indicating that there is capacity to accept recovered energy).

[0144] Mode execution:

[0145] Once the triggering conditions are met, the ECU sends a command to the solenoid valve to engage the PTO with the transmission, and the generator begins to rotate.

[0146] The ECU adjusts the generator's excitation current (or equivalent control parameters) via PWM signals based on the current vehicle speed, generator speed, energy storage device SOC, and preset energy recovery intensity level (which may be selected by the driver or automatically optimized by the system). The goal is to convert the vehicle's kinetic or potential energy into electrical energy as efficiently as possible without significantly affecting driving smoothness.

[0147] Real-time adaptive adjustment based on operating conditions: For example, at higher vehicle speeds, excitation can be appropriately increased to improve regenerative power; when the state of charge (SOC) approaches its upper limit or the vehicle speed is too low, excitation is gradually reduced to smoothly exit energy recovery. The control algorithm considers the generator's efficiency map (MAP) to ensure it operates in the most efficient region possible.

[0148] Predictive Control: (Optional Advanced Function) If the system integrates navigation information (such as a long downhill slope ahead, traffic lights) or learns the driver's driving habits, the ECU can anticipate energy recovery opportunities in advance and more proactively adjust the PTO engagement timing and generator excitation strategy to maximize overall energy recovery. For example, if the SOC is low before entering a long downhill slope, it can prepare to enter a strong energy recovery state in advance.

[0149] Triggering and controlling the auxiliary braking mode:

[0150] Trigger condition determination: The ECU monitors one or more of the following combinations of conditions:

[0151] If the driver depresses the brake pedal at a depth / rate exceeding a preset threshold, it indicates that stronger braking force is required.

[0152] The driver requests auxiliary braking via a dedicated auxiliary braking control lever or button, and may have selected the desired braking level.

[0153] When descending a long slope, even if the driver does not apply the brakes firmly, the ECU will determine the vehicle speed based on the vehicle speed, acceleration, and slope to actively control the vehicle speed to prevent speeding.

[0154] Mode execution:

[0155] If the PTO is not yet engaged, the ECU immediately controls its engagement.

[0156] Based on the driver's braking demand (from the brake pedal signal or auxiliary braking gear selection), the current vehicle speed, and the energy storage device's capacity (such as SOC and temperature), the ECU significantly increases (or precisely sets) the generator's excitation current via a PWM signal. This causes the generator to produce a strong reverse electromagnetic torque as auxiliary braking force.

[0157] Multi-level braking torque setting: The system can achieve multiple (e.g., 3-5) auxiliary braking levels. Each level corresponds to a target braking torque (or deceleration) range. ECU 4 controls the generator excitation through a closed loop to ensure that the actual output auxiliary braking torque reaches the level corresponding to the selected level. The driver can select the level through the operating interface (such as a lever, steering wheel paddles, or virtual buttons integrated into the central control screen), or ECU 4 can automatically match the appropriate braking level based on the brake pedal depth and vehicle speed.

[0158] Enhanced Emergency Braking: When the ECU detects an emergency braking signal (e.g., the brake pedal is depressed very quickly, or in conjunction with a forward collision warning system), it immediately boosts the generator's excitation to the maximum allowed value to provide maximum auxiliary braking torque, working in conjunction with the main braking system to minimize braking distance. At this time, special attention is paid to coordination with the ABS system; once ABS is activated, the generator's braking force may be adjusted or temporarily reduced to prevent wheel lock-up.

[0159] During assisted braking, the generator still converts the vehicle's kinetic energy into electrical energy and delivers it to the energy storage device.

[0160] Mode switching and collaborative control:

[0161] The ECU ensures smooth and rapid switching between different modes. For example, when switching from energy recovery mode to assisted braking mode, the excitation current increases rapidly as needed. When the system disengages (PTO disengages), the excitation current gradually decreases to avoid sudden load changes. Through communication with vehicle stability systems such as ABS / ESP, the ECU ensures that the intervention of assisted braking function will not compromise vehicle stability under any circumstances.

[0162] System integration and compatibility include:

[0163] PTO interface: A PTO interface conforming to commercial vehicle standards is selected, which facilitates installation on different models of transmissions.

[0164] Generator Dimensions and Installation: The generator is designed to be compact and features standardized mounting brackets.

[0165] CAN bus communication: It adopts the standard CAN communication protocol (such as SAE J1939) and seamlessly integrates with the vehicle's existing electronic control system.

[0166] Modular software: The ECU's control software adopts a modular design, which facilitates parameter calibration and function configuration for different vehicle models. For example, energy recovery intensity, the number of auxiliary braking gears, and the braking torque of each gear can all be customized.

[0167] Through the detailed technical solution described above, the present invention provides an energy recovery and auxiliary braking system with a compact structure, intelligent control, and high functional integration, which can significantly improve the overall performance of heavy trucks.

[0168] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dynamic energy management system for the powertrain of a heavy-duty commercial vehicle, characterized in that, include: The power take-off (PTO) extracts rotational power from the gear train of the transmission as needed to provide mechanical energy input to the generator; The solenoid valve receives electrical signal commands from the control unit and drives the clutch action of the power take-off by controlling the air circuit, thereby realizing the engagement or disengagement of the power take-off and the power output gear of the transmission. The generator converts the mechanical energy input from the power take-off unit into electrical energy and sends it to the energy storage device; The control unit acquires the status parameters of the heavy commercial vehicle in real time, determines the current operating condition of the vehicle and the driver's intention based on the status parameters, and generates decision instructions based on the operating condition and the driver's intention.

2. The dynamic energy management system for the powertrain of heavy-duty commercial vehicles according to claim 1, characterized in that, The status parameters include one or more of the following: vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, ABS status, gear information, energy storage device state of charge, and temperature.

3. The energy dynamic management system for the powertrain of heavy-duty commercial vehicles according to claim 1, characterized in that, The operating conditions include one or more of the following: acceleration, constant speed, coasting, deceleration, braking, uphill, and downhill.

4. The dynamic energy management system for the powertrain of heavy-duty commercial vehicles according to claim 1, characterized in that, The generator includes: In power generation mode, the mechanical energy input from the power take-off unit is converted into three-phase alternating current; In the auxiliary braking mode, the excitation current or equivalent magnetic field strength is controlled by the control unit to generate an electromagnetic torque that is opposite to the direction of wheel rotation. This electromagnetic torque is transmitted to the wheels through the power take-off and transmission to form an auxiliary braking force. At this time, the generator is still in the power generation state, forcibly converting the vehicle's kinetic / potential energy into electrical energy.

5. The dynamic energy management system for the powertrain of heavy-duty commercial vehicles according to claim 1, characterized in that, The generator includes: Adjustable excitation systems, for hybrid excitation or electrically excitation synchronous generators containing excitation windings, allow the control unit to change the strength of the main magnetic field inside the generator by controlling the magnitude of the DC current supplied to the excitation windings. For permanent magnet synchronous generators, the control unit indirectly affects the air gap magnetic field and output torque / voltage by controlling the phase and amplitude of the stator current. Pulse width modulation (PWM) is a power drive module that is integrated internally or externally connected to the control unit. According to the instructions of the control unit, it adjusts the average current value supplied to the generator excitation winding or controls the stator phase current. By adjusting the duty cycle of the PWM signal, it controls the generator magnetic field strength, output voltage or braking torque.

6. The energy dynamic management system for the powertrain of heavy-duty commercial vehicles according to claim 1, characterized in that, The control unit includes: The data acquisition and processing module acquires vehicle speed, engine speed, accelerator pedal opening, brake pedal travel and status, anti-lock braking system (ABS) status, gear information, energy storage device charge status, and temperature in real time via the vehicle bus. The decision-making logic and mode switching module intelligently determines the vehicle's current operating condition and the driver's intentions based on collected multi-source information, and decides which operating mode the system should be in: In standby mode, when neither energy recovery nor auxiliary braking is required, the control unit controls the solenoid valve to disconnect the power take-off unit from the transmission, and the generator does not work. In energy recovery mode, when the vehicle deceleration, braking, or downhill coasting is detected, the control unit controls the solenoid valve to engage the power take-off and drive the generator to work; at the same time, the control unit controls the excitation of the generator through PWM according to the vehicle speed, SOC, and energy recovery potential. In assisted braking mode, when the driver has a clear need for assisted braking, the control unit controls the power take-off to engage and increases the excitation of the generator to obtain reverse braking torque. In this mode, energy recovery still takes place. In the control signal output mode, a switching signal is output to the solenoid valve to control the on / off state of the power take-off unit; a PWM control signal is output to the generator's excitation system to adjust the generator's magnetic field strength / output torque.

7. The energy dynamic management system for the powertrain of heavy-duty commercial vehicles according to claim 1, characterized in that, The generator adopts a multi-pole permanent magnet synchronous or hybrid excitation synchronous structure.

8. A method for dynamic energy management of a powertrain system in a heavy-duty commercial vehicle, characterized in that, The following work mode determination and switching process is included: Real-time acquisition of vehicle status information; Based on the aforementioned status information, determine whether the triggering conditions for the energy recovery mode are met; When the status information determines that the triggering conditions for the energy recovery mode are met, the energy recovery mode is entered. First, the solenoid valve is controlled to engage the power take-off unit to adjust the excitation of the generator. Then, the SOC, vehicle speed and driver operation commands are monitored in real time to adjust the excitation intensity. The status information is checked again to determine whether the triggering conditions for the energy recovery mode are met. If so, the steps of entering the energy recovery mode are repeated. Otherwise, the energy recovery mode is exited. When the status information determines that the triggering conditions of the energy recovery mode are not met, it is determined whether the conditions of the auxiliary braking mode are met. If the conditions of the auxiliary braking mode are met, the auxiliary braking mode is entered, and the solenoid valve is controlled to engage the power take-off unit to enhance the excitation of the generator. If the auxiliary braking mode conditions are not met, the power take-off remains disengaged.

9. A method for dynamic energy management of the powertrain system of a heavy-duty commercial vehicle, characterized in that, The following energy recovery control processes are included: Real-time acquisition of vehicle status information; Based on the status information, determine whether the energy recovery start-up conditions are met; When the status information determines that the energy recovery start-up conditions are met, the solenoid valve is first controlled to engage the power take-off unit to start the generator. Then, the target excitation intensity is determined according to the real-time operating conditions, and the closed-loop control PWM signal is output to the generator's excitation system. If the status information indicates that the energy recovery start-up conditions are not met, monitoring will continue.

10. A method for dynamic energy management of a powertrain system in a heavy-duty commercial vehicle, characterized in that, The following auxiliary braking control procedures are included: Real-time acquisition of vehicle status information; Based on the status information, determine whether the auxiliary braking triggering condition is met; When the status information determines that the auxiliary braking triggering condition is met, the power take-off is first engaged, the generator is started, and then the target braking torque is calculated based on the intensity of the auxiliary braking request, the current vehicle speed, and the state of charge (SOC). The calculation results are then converted into target excitation current and target PWM duty cycle; finally, the generator excitation current is adjusted using PWM to apply reverse electromagnetic braking torque. If the status information indicates that the auxiliary braking triggering conditions are not met, monitoring continues.

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