A drive and energy recovery integrated control system for a mining dump truck

Abstract

The present application relates to the technical field of mine vehicle power system, and discloses a driving and energy recovery integrated control system for mine dump truck, which comprises an energy source module, a four-motor driving module, a transmission brake module, a high-voltage power distribution module and a whole vehicle control module; the present application adopts the architecture of four-motor parallel centralized driving, breaks through the upper limit of power and torque of a single motor, realizes sufficient traction force output of large-tonnage mine dump truck under extreme working conditions, has fault redundancy capability, improves system reliability, adopts fixed-speed-ratio reduction gearbox instead of multi-gear transmission box, eliminates power interruption phenomenon in the shifting process, avoids sudden speed drop and impact jerk, improves driving safety and comfort, adopts high-voltage platform, reduces system current, reduces cable diameter and whole vehicle weight, reduces energy consumption and heat generation, and improves charging speed, and meets the operation demand of short-time energy supplement in mine area.

Description

Technical Field

[0001] This invention relates to the field of power system technology for mining vehicles, specifically to an integrated control system for drive and energy recovery in mining dump trucks. Background Technology

[0002] Mining dump trucks are core equipment for earthmoving in open-pit mines and large-scale construction projects, undertaking the transfer of materials such as ore and slag. Their operational efficiency directly affects the overall production capacity and economic benefits of the mine. With the continuous expansion of mining scale and increasingly stringent environmental protection requirements, mining dump trucks are developing towards larger sizes, electrification, and intelligence, placing higher demands on the power performance, reliability, energy efficiency, and safety performance of the drive system. The drive system of a mining dump truck is its core component, responsible for converting energy from the energy source into mechanical energy to drive the vehicle. The energy recovery system converts the kinetic energy generated during braking, coasting, and downhill driving into electrical energy for storage, achieving energy recycling. This is crucial for reducing vehicle energy consumption and extending driving range. Integrated control of the drive and energy recovery systems enables their coordinated operation, further improving the overall system performance.

[0003] The existing patent CN119858455A discloses an electric braking control system and method for an electric-driven mining dump truck. It achieves energy recovery through priority electric braking, but its brakes still use a traditional structure, resulting in easy attenuation of braking force during long-distance heavy-load downhill driving, and it lacks electro-hydraulic coordination and range-extending power coupling control. Currently, the mainstream new energy drive systems for mining dump trucks adopt a single-motor or dual-motor matching multi-speed gearbox technology. Peak output capacity is limited by the power and torque limits of a single motor, failing to meet the traction requirements of heavy-tonnage products under extreme conditions such as full-load climbing and starting on slippery surfaces. Furthermore, its redundancy capability for handling faults is weak. The gearbox must interrupt the motor torque output to complete the shift, and this power interruption causes a sudden drop in vehicle speed and jerking. Failure to shift may cause the vehicle to roll backwards or even overturn on slopes, seriously affecting driving safety and comfort. Limited by the maturity and cost of high-voltage components for large-tonnage mining dump trucks, the industry generally adopts lower voltage platforms, creating technological inertia. However, this results in slow charging speeds for vehicles with large capacities, making it difficult to meet the short-term energy replenishment needs of mining operations. Higher current cables are required for the same power output, necessitating thicker wires, increasing vehicle weight and installation complexity, while also leading to higher energy consumption and significant heat generation. Traditional drum brakes, dry disc brakes, and ordinary wet brakes have limited braking capacity and cannot meet the braking requirements of large mining dump trucks for long-distance, heavy-load downhill driving. Under continuous braking, the friction pad temperature rises sharply, braking force is severely reduced, and brake failure can even lead to accidents. A single braking system lacks backup braking force, compromising operational safety in case of failure. Therefore, developing an integrated drive and energy recovery control system for mining dump trucks is of great significance. Summary of the Invention

[0004] The purpose of this invention is to overcome the shortcomings of the prior art and provide an integrated drive and energy recovery control system for mining dump trucks. It can solve the problems of insufficient power, power interruption, slow charging and high energy consumption due to low voltage platform, weak braking ability and poor safety of existing mining dump truck drive systems.

[0005] To solve the above-mentioned technical problems, the present invention provides the following technical solution: an integrated drive and energy recovery control system for mining dump trucks, the system comprising: an energy source module, a four-motor drive module, a transmission and braking module, a high-voltage power distribution module, and a vehicle control module;

[0006] The energy source module is used to provide the electrical energy required for the operation of the vehicle and to output electrical energy to the high-voltage power distribution module;

[0007] The high-voltage power distribution module is used to realize the distribution and safety protection of high-voltage power, and to distribute power to the four-motor drive module;

[0008] The four-motor drive module is used to convert electrical energy into mechanical energy and realize the coordinated output of multiple motors, outputting mechanical energy to the transmission and braking module;

[0009] The transmission braking module is used to transmit power and provide braking capability to drive the wheels to rotate.

[0010] The vehicle control module is used to realize the integrated and coordinated control of various subsystems. It interacts bidirectionally with the energy source module, the four-motor drive module, the transmission and braking module, and the high-voltage power distribution module. It receives the operating status data of each module, generates and sends control commands according to the vehicle operating conditions and driver operation commands, and completes the coordinated operation of drive torque distribution control, electric braking and hydraulic braking coordinated control, energy recovery control and range-extending operation mode switching control.

[0011] Furthermore, the four-motor drive module includes four permanent magnet synchronous drive motors and four independent drive motor controllers. The four drive motors are arranged symmetrically, and their output shafts are coaxially coupled to the same coupling output shaft through rigid couplings. Each drive motor controller controls the operating state of one drive motor, receives torque commands sent by the vehicle control module, and adjusts the output torque and speed of the drive motor. The output torque of the four drive motors is centrally transmitted to the transmission and braking module through the coupling shaft, realizing the superposition output of the torque of multiple motors.

[0012] Furthermore, the vehicle control module performs the following operations when distributing drive torque:

[0013] Collect signals of accelerator pedal opening, vehicle speed, battery SOC, motor speed and motor temperature, and calculate the total torque required for the vehicle based on the collected signals;

[0014] Based on the current efficiency characteristics of each drive motor, the required torque of a single motor is decomposed using a four-motor optimal torque allocation algorithm. The algorithm formula is as follows: ,in This represents the total torque required by the entire vehicle. Let be the efficiency weighting coefficient for the i-th drive motor. The maximum allowable output torque of the i-th drive motor is represented by the weighting coefficient. The efficiency values ​​were obtained by calibration using a drive motor bench efficiency MAP chart and then normalized based on the real-time speed and temperature of each motor.

[0015] The required torque of each drive motor is set as follows: It then sends the torque command to the corresponding drive motor controller, monitors the actual output torque of each drive motor in real time, and dynamically corrects the torque distribution result.

[0016] Furthermore, the transmission braking module includes a fixed-ratio planetary gear reducer, a drive shaft, and a high-load-bearing wet brake drive axle. The input shaft of the fixed-ratio planetary gear reducer is connected to the coupling output shaft of the four-motor drive module, and the output shaft of the fixed-ratio planetary gear reducer is connected to the drive shaft. The drive shaft is connected to the input shaft of the main reducer of the high-load-bearing wet brake drive axle. The high-load-bearing wet brake drive axle integrates a multi-plate fully hydraulic wet brake. The friction plates of the fully hydraulic wet brake are made of copper-based powder metallurgy material and are immersed in special cooling oil.

[0017] Furthermore, the vehicle control module performs the following operations when conducting coordinated control of electric and hydraulic braking:

[0018] Collect signals of brake pedal opening, vehicle speed, battery SOC, and motor speed, and calculate the total braking force requirement of the vehicle based on the collected signals;

[0019] Determine whether the battery SOC is below the preset upper limit and whether the motor speed is within the allowable range for power generation;

[0020] When the judgment result is yes, the maximum available electric braking force is calculated using the electro-hydraulic braking force distribution algorithm. The algorithm formula is as follows: ,in For the total braking force requirements of the entire vehicle, The electric motor is the power source, and μ is the hydraulic braking output coefficient. The maximum hydraulic braking force of the wet brake is determined by the coefficient μ through a real vehicle test under heavy-load downhill braking conditions in the mining area. It is dynamically determined based on the boundary conditions of battery SOC and motor speed, and the electric braking force is preferentially allocated to the four drive motors.

[0021] When the electric braking force is less than the total braking force requirement, the remaining braking force requirement is calculated, and a hydraulic braking command is sent to the transmission braking module, so that the remaining braking force is provided by the fully hydraulic wet brake.

[0022] Furthermore, the energy source module includes two configurations: a pure electric energy source and a range-extending energy source. The pure electric energy source consists of a modular high-capacity power battery pack, which adopts a standardized module design. The range-extending energy source consists of a modular high-capacity power battery pack and a range extender assembly connected in parallel. The range extender assembly consists of a high-horsepower diesel engine and a high-power range extender coaxially connected. The electrical energy output by the range extender assembly is directly fed into the high-voltage DC bus.

[0023] Furthermore, the vehicle control module performs the following operations when switching between range-extended operation modes:

[0024] Collect battery SOC, vehicle power demand, and range extender operating status signals. When the battery SOC is higher than the first preset threshold and the vehicle power demand is less than the battery's maximum allowable discharge power, control the engine and range extender to stop and switch to pure electric drive mode.

[0025] When the battery SOC is lower than the second preset threshold or the vehicle's required power is greater than the battery's maximum allowable discharge power, the range extender assembly is activated and switched to range extender drive mode.

[0026] When the vehicle's required power exceeds the maximum output power of the range extender assembly, a range extender power coupling algorithm controls the coordinated output of dual energy sources. The algorithm formula is as follows: ,in For the power required by the whole vehicle, Where λ is the maximum output power of the battery, and λ is the output weighting coefficient of the range extender. The maximum output power of the range extender assembly is determined by the coefficient λ, which is based on the curve fitting of the optimal fuel economy range of the range extender. Combined with the dynamic adjustment of the battery SOC threshold, the power battery pack and the range extender assembly are controlled to output electrical energy simultaneously, switching to a strong power mode.

[0027] Furthermore, the high-voltage power distribution module includes a high-voltage power distribution box, which integrates a main contactor, a pre-charge contactor, a fuse, a current sensor, a voltage sensor, and an insulation monitoring unit. The input end of the high-voltage power distribution box is connected to the energy source module, and the output end is connected to the controllers of four drive motors respectively. According to the instructions of the vehicle control module, the high-voltage power distribution box completes the on-off control and distribution of power, and at the same time collects current, voltage and insulation status signals and sends them to the vehicle control module.

[0028] Furthermore, the vehicle control module performs the following operations when performing motor fault redundancy control:

[0029] The system collects the motor operating status and fault signals sent by each drive motor controller in real time. When a fault is detected in any one or more drive motors, the faulty motor is marked and the transmission of torque commands to the faulty motor is stopped.

[0030] Recalculate the maximum total output torque that the remaining normal motors can provide, and adjust the total torque required by the vehicle based on the remaining maximum total output torque.

[0031] The adjusted total torque demand is redistributed to the remaining normal motors to maintain vehicle operation.

[0032] Furthermore, the vehicle control module includes a vehicle controller (VCU), a motor controller (MCU), a battery management system (BMS), and a brake controller (BCU). The VCU communicates with the MCU, BMS, and BCU via a CAN bus. The MCU collects the speed, torque, and temperature operating parameters of the drive motor and sends them to the VCU. The BMS collects the voltage, current, temperature, and SOC status parameters of the power battery pack and sends them to the VCU. The BCU collects the brake pedal opening and brake pressure operating parameters and sends them to the VCU.

[0033] Compared with existing technologies, this integrated drive and energy recovery control system for mining dump trucks has the following advantages:

[0034] This invention, by employing a four-motor parallel centralized drive architecture, breaks through the power and torque limits of a single motor, enabling sufficient traction output for large-tonnage mining dump trucks under extreme working conditions. It also features fault redundancy, improving system reliability. By replacing multi-speed gearboxes with fixed-ratio reduction gearboxes, it eliminates power interruptions during gear shifts, preventing sudden speed drops and jerking, thus improving driving safety and comfort. The use of a high-voltage platform reduces system current, cable diameter, and overall vehicle weight, lowering energy consumption and heat generation while increasing charging speed to meet short-term energy replenishment needs in mining areas. The combined use of electric braking and fully hydraulic wet braking enhances braking capability on long-distance, heavy-load downhill sections, preventing brake force decay and achieving efficient energy recovery, reducing vehicle energy consumption. Furthermore, the two braking methods act as backups for each other, enhancing the safety of the braking system.

[0035] Other advantages, objectives and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination or study, or may be learned from the practice of the invention. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0037] Figure 1 This is a schematic diagram of an integrated drive and energy recovery control system for mining dump trucks.

[0038] Figure 2 This is a flowchart of an integrated drive and energy recovery control system for mining dump trucks.

[0039] Figure 3 This is a flowchart of the vehicle control module distributing drive torque. Detailed Implementation

[0040] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description of the specific implementation methods, structures, features and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided below.

[0041] This invention provides an integrated drive and energy recovery control system for mining dump trucks. The system uses the vehicle control module as the core control unit and integrates five core components: energy source module, four-motor drive module, transmission and braking module, and high-voltage power distribution module, to construct an integrated collaborative control architecture for drive and energy recovery. The energy source module provides both pure electric and range-extended power supply options to meet the range and refueling needs of different mining areas. The high-voltage power distribution module handles high-voltage power distribution, safety protection, and status monitoring. The four-motor drive module uses four permanent magnet synchronous drive motors in a coaxial coupling layout to achieve torque superposition output, breaking through the power limit of a single motor. The transmission and braking module integrates a fixed-ratio planetary gear reducer and a high-load-bearing wet brake drive axle, eliminating the need for a multi-speed gearbox and power interruption. The vehicle control module achieves bidirectional data interaction between subsystems via a CAN bus. Relying on the optimal torque distribution algorithm for the four motors, the electro-hydraulic braking force distribution algorithm, and the range-extending power coupling algorithm, it achieves integrated and coordinated operation of drive control, energy recovery control, braking control, and operating mode switching. It also incorporates motor fault redundancy control logic, comprehensively solving the technical problems of insufficient drive power, power interruption during gear shifting, brake fade on long downhill slopes, high energy consumption, and poor fault redundancy in traditional mining dump trucks. It is precisely adapted to the actual application scenarios of heavy-duty transportation in open-pit mines, long-distance downhill driving, starting on slippery surfaces, and continuous high-intensity operations. The following is a detailed description with reference to specific embodiments.

[0042] This embodiment applies to large-tonnage mining dump trucks used in open-pit mines. The vehicle's rated load capacity matches the standards for large-scale mining and transportation. Operating scenarios cover typical conditions such as fully loaded uphill climbing, unloaded coasting, long-distance heavy-load downhill driving, and driving on muddy and slippery roads in mining areas. The overall system structure is as follows: Figure 1 As shown. After the system is powered on and initialized, the vehicle control module starts first, establishing a two-way data interaction channel with the energy source module, the four-motor drive module, the transmission and braking module, and the high-voltage power distribution module. Each sub-module enters standby mode simultaneously, uploading operating status parameters in real time and receiving control commands, forming a closed-loop control system for the entire process, providing stable power and braking guarantees for continuous mining operations.

[0043] The vehicle control module is the decision-making core of the entire system, consisting of four main units: the vehicle controller (VCU), the motor controller (MCU), the battery management system (BMS), and the brake controller (BCU). These units communicate via a CAN bus for high-speed, zero-latency data exchange. The VCU, as the central control unit, is responsible for coordinating the execution and scheduling of all control strategies, serving as the brain of the system's collaborative operation. The MCU collects real-time operating parameters from the four drive motors, including speed, output torque, housing temperature, and winding temperature, and uploads them to the VCU at a fixed high frequency, ensuring continuous real-time monitoring of the motor's operating status.

[0044] The Battery Management System (BMS) continuously collects key status parameters of the modular power battery pack, such as individual cell voltage, total voltage, charging and discharging current, cell temperature, and remaining SOC (State of Charge), providing accurate data for energy management, mode switching, and safety protection. The Brake Control Unit (BCU) collects signals in real time, including driver brake pedal opening, brake line pressure, and drive axle braking status, accurately reflecting braking intentions and the real-time status of the braking system. Parameter acquisition and command transmission from all sub-units are executed synchronously, ensuring the real-time performance, accuracy, and stability of the vehicle control strategy, adapting to the rapidly changing operating conditions in mining environments.

[0045] The high-voltage power distribution module adopts an integrated high-voltage distribution box, which integrates main contactors, pre-charge contactors, fuses, current sensors, voltage sensors, and insulation monitoring units. The hardware layout is compact, and the protection level is suitable for the harsh environment of mines, including dust, vibration, and humidity. The input end of the high-voltage distribution box is directly connected to the energy source module, receiving high-voltage power from a pure electric energy source or a range extender energy source. The output end is independently connected to the controllers of four drive motors, achieving precise multi-path distribution of high-voltage power. Throughout system operation, the high-voltage distribution box strictly follows the instructions of the vehicle control module, completing the on / off control, pre-charge control, and overload protection of the high-voltage circuit. Simultaneously, it collects the current and voltage values ​​of the high-voltage circuit in real time through current and voltage sensors, and the insulation monitoring unit continuously monitors the insulation resistance value of the high-voltage system. All monitoring data is transmitted back to the vehicle control module in real time. Once an abnormality such as overcurrent, overvoltage, or insulation fault is detected, the system immediately cuts off the high-voltage circuit, ensuring the safe operation of the high-voltage system from a hardware perspective and preventing safety accidents such as fires and electric shocks caused by high-voltage faults in mining operations.

[0046] The energy source module provides a continuous and stable power supply for this embodiment, offering two switchable configurations: a pure electric energy source and a range-extended energy source, to meet the refueling conditions and long-term operation needs of different mining areas. The pure electric energy source uses a modular, high-capacity power battery pack with a standardized module design. The modules are uniform in size and have universal electrical interfaces, facilitating rapid replacement, maintenance, and capacity expansion on-site. In pure electric mode, the power battery pack independently outputs high-voltage power, adapting to the short-distance, short-duration, and environmentally controlled operational needs of mining areas. The range-extended energy source consists of a modular, high-capacity power battery pack connected in parallel with a range extender assembly. The range extender assembly uses a structure with a high-horsepower diesel engine and a high-power range extender rigidly connected coaxially. When the engine is running, it directly drives the range extender to generate electricity, and the output high-voltage power is directly fed into the high-voltage DC bus, forming a dual-energy supply system with the power battery pack, solving the industry pain points of insufficient range and inconvenient refueling for pure electric vehicles.

[0047] The vehicle control module, configured for the range-extended energy source, executes refined range-extended operation mode switching logic. It collects three main types of signals in real time: battery SOC remaining charge, real-time vehicle power demand, and range extender operating status. Based on these signal values, it automatically and seamlessly switches between pure electric drive mode, range-extended drive mode, and high-power mode. When the battery SOC exceeds a first preset threshold and the vehicle power demand is less than the battery's maximum allowable discharge power, the vehicle control module immediately sends a shutdown command, stopping the diesel engine and range extender. The system switches to pure electric drive mode, powered independently by the battery pack, achieving zero emissions and low noise operation, suitable for operations in strictly controlled environmental areas like mining areas. When the battery SOC falls below a second preset threshold or the vehicle power demand exceeds the battery's maximum allowable discharge power, the vehicle control module sends a start command. The range extender assembly quickly starts and enters a stable power generation state, and the system switches to range-extended drive mode, powered independently by the range extender, ensuring continuous and uninterrupted vehicle operation and preventing mine transportation shutdowns due to insufficient battery power.

[0048] When the vehicle enters extreme operating conditions requiring high power, such as fully loaded uphill climbing or starting on slippery surfaces, and the total power demand of the vehicle exceeds the maximum output power of the range extender assembly, the vehicle control module activates the range extender power coupling algorithm. The formula is as follows: In the specific implementation process of this embodiment, Represents the real-time power demand of the vehicle. It is a real-time value calculated by the vehicle control module based on the accelerator pedal opening, vehicle speed, and vehicle load weight, and is perfectly matched to the actual power demand of the vehicle. This represents the maximum allowable output power of the power battery pack, which is determined by the battery management system based on cell temperature, remaining SOC, and voltage status to ensure safe battery operation. The output weighting coefficient of the range extender is obtained by obtaining the optimal efficiency range curve through fuel economy tests on the range extender bench and then calculating it through professional curve fitting. In actual operation, it is dynamically adjusted in combination with the battery SOC threshold to ensure that the range extender always operates in the speed range with the highest fuel efficiency, thereby reducing fuel consumption. This represents the rated maximum output power of the range extender assembly, a fixed parameter calibrated at the factory. Through this algorithm, the vehicle control module precisely coordinates the simultaneous output of electrical energy from the power battery pack and the range extender assembly, achieving dual-energy coupling and supply. The system switches to a powerful power mode, perfectly meeting the high torque and high power output requirements of large-tonnage mining dump trucks under extreme operating conditions.

[0049] The four-motor drive module is the core execution unit for achieving high torque output in this embodiment. It consists of four permanent magnet synchronous drive motors and four independent drive motor controllers. The four drive motors are arranged symmetrically, and their output shafts are coaxially coupled to the same coupling output shaft via rigid couplings, ensuring that the output power of the four motors is without deviation and without the superposition of mechanical losses. Each drive motor controller independently controls one drive motor and exclusively receives torque commands sent by the vehicle control module, precisely adjusting the output torque and speed of the drive motor. The output torque of the four motors is centrally transmitted to the transmission and braking module through the coupling shaft, realizing the synchronous superposition of torque from multiple motors. This completely breaks through the power limit of traditional single-motor and dual-motor systems and solves the industry problem of insufficient traction force in large-tonnage mining dump trucks.

[0050] The complete process of drive torque distribution is as follows Figure 3 As shown, when the vehicle is in driving mode, the vehicle control module first initiates a multi-dimensional signal acquisition process, collecting signals such as accelerator pedal opening, vehicle speed, battery SOC, motor speed, and motor temperature. Based on the current efficiency characteristics of each drive motor, the total torque demand of the vehicle is calculated using a four-motor optimal torque distribution algorithm. The algorithm formula is as follows: .

[0051] In the specific implementation process of this embodiment, The total torque required for the entire vehicle is the total torque value required for the vehicle to run under driving conditions. The efficiency weighting coefficient of the i-th drive motor is obtained through the calibration of the drive motor bench efficiency MAP map. First, efficiency data of each motor at different speeds and temperatures are collected in professional bench tests to form a complete motor efficiency MAP map. Then, the efficiency values ​​corresponding to the real-time speed and temperature of each motor are normalized. Finally, the efficiency weighting coefficient of each motor is calculated to ensure that the motor with higher operating efficiency is allocated more torque, thereby improving the overall vehicle drive efficiency from the control level. The maximum allowable output torque of the i-th drive motor is determined in real time by the motor controller based on motor speed, temperature, and insulation status to ensure safe motor operation. The individual torque requirements of each drive motor are set as follows: The system sends the torque command to the corresponding drive motor controller. The vehicle control module monitors the actual output torque of each drive motor in real time and dynamically corrects the torque distribution results to ensure that the four motors always operate in a coordinated and efficient manner, with smooth and precise power output, without shock or vibration.

[0052] The transmission and braking module undertakes the dual core functions of power transmission and braking execution. It consists of three parts: a fixed-ratio planetary gear reducer, a drive shaft, and a high-load-bearing wet brake drive axle. This module completely eliminates the traditional multi-speed gearbox, adopting a fixed-ratio design to eliminate power interruption during gear shifting from the structural source. The input shaft of the fixed-ratio planetary gear reducer is directly connected to the coupling output shaft of the four-motor drive module, receiving the large torque power from the superimposed power of the four motors. The output shaft is rigidly connected to the drive shaft, and the other end of the drive shaft is connected to the input shaft of the main reducer of the high-load-bearing wet brake drive axle. After reduction and torque amplification, the power is smoothly transmitted to the wheels, driving the vehicle. The fixed-ratio planetary gear reducer has a simple structure, high transmission efficiency, and low mechanical failure rate, making it fully suitable for the continuous high-intensity and high-vibration operation requirements of mines, reducing the frequency and cost of mine maintenance.

[0053] The high-load-bearing wet-braking drive axle integrates a multi-plate fully hydraulic wet brake. The brake friction pads are made of copper-based powder metallurgy material, whose wear resistance and thermal conductivity far exceed those of traditional friction materials. The friction pads are completely immersed in special cooling oil, which continuously circulates and quickly dissipates the large amount of heat generated during braking. This prevents the friction pad temperature from rising sharply during long-distance heavy-load downhill driving, thus avoiding brake force attenuation and completely solving the major safety hazard of brake failure in traditional brake systems. In the core braking control stage, the vehicle control module executes the coordinated control logic of electric and hydraulic braking. First, it collects four key signals: brake pedal opening, real-time vehicle speed, battery SOC, and motor speed. Based on these signals, it accurately calculates the total braking force requirement of the entire vehicle, perfectly matching the driver's braking intention.

[0054] The vehicle control module then determines the energy recovery conditions, namely whether the battery SOC is below a preset upper limit and whether the motor speed is within the allowable range for power generation. If both conditions are met, the electro-hydraulic braking force distribution algorithm is activated, with the following formula: In the specific implementation process of this embodiment, The total braking force requirement of the vehicle is the total torque value required for safe braking of the vehicle. Powered by an electric motor, the system generates electricity through four drive motors operating in reverse, simultaneously converting the kinetic energy from vehicle braking, coasting, and long downhill runs into high-voltage electrical energy. μ represents the hydraulic braking output coefficient, calibrated through real-vehicle tests under heavy-load downhill braking conditions in mining areas. The tests collected braking data at different battery SOCs and motor speeds, and combined with braking safety requirements and energy recovery efficiency to determine the final coefficient value. In actual operation, the coefficient is dynamically adjusted based on battery SOC and motor speed boundary conditions to balance braking performance and energy recovery efficiency. This is the maximum hydraulic braking force of the wet brake, a fixed parameter calibrated at the factory for the drive axle.

[0055] During algorithm execution, the vehicle control module prioritizes allocating electric braking force to the four drive motors. The motors quickly enter generator mode, converting the kinetic energy from braking, coasting, and long downhill runs into high-voltage electrical energy. This energy is then stably fed back to the power battery pack in the energy source module via the high-voltage power distribution module, achieving energy recycling and effectively reducing vehicle energy consumption and increasing driving range. When the electric braking force is less than the vehicle's total braking force requirement, the vehicle control module quickly calculates the remaining braking force demand and immediately sends a hydraulic braking command to the transmission braking module. The fully hydraulic wet brakes instantly activate to supplement the remaining braking force. The seamless integration and coordinated operation of electric and hydraulic braking achieves efficient energy recovery while ensuring sufficient and stable braking force, with fast braking response and no brake fade. If the energy recovery conditions are not met, the vehicle control module directly sends a hydraulic braking command, and the fully hydraulic wet brakes independently execute braking, ensuring safe and controllable braking under any operating condition and environment.

[0056] The overall system workflow in this embodiment is as follows: Figure 2 As shown, after the system is powered on and initialized, the vehicle control module enters a continuous signal acquisition state, acquiring all operational data in real time, including vehicle operating conditions, driver operations, and the status of each submodule. It then accurately determines whether the vehicle is currently in driving mode or braking and coasting downhill mode. If it is determined to be in driving mode, the vehicle controller immediately calculates the total torque required by the vehicle and activates the optimal torque distribution algorithm for the four motors. The four drive motors work together to output high torque, which is smoothly transmitted to the wheels through the transmission braking module, driving the vehicle. Simultaneously, the vehicle control module automatically switches between pure electric mode, range-extended mode, and powerful mode based on the battery's remaining SOC and the vehicle's required power, ensuring a continuous and stable power supply. If it is determined to be braking and coasting downhill mode, the vehicle control module prioritizes determining the energy recovery conditions. If the conditions are met, the electro-hydraulic braking force distribution algorithm is executed, with electric braking recovering energy combined with hydraulic braking assistance. If the conditions are not met, the fully hydraulic wet braking is directly activated, and all recovered electrical energy is efficiently fed back to the energy source module, completing the closed-loop energy utilization. The vehicle continues to operate stably until the operation ends or the system is powered off normally.

[0057] To further enhance the system's reliability under harsh mining conditions, this embodiment incorporates a dedicated motor fault redundancy control function. The vehicle control module collects real-time motor operating status and fault signals from the four drive motor controllers, covering various common fault types such as motor overload, over-temperature, short circuit, and open circuit. When a fault is detected in any one or more drive motors, the vehicle control module immediately marks the faulty motor, stops sending torque commands to it, and cuts off its power output to prevent the fault from escalating and causing more serious equipment damage. Subsequently, the vehicle control module recalculates the maximum total output torque that the remaining normal motors can provide. Based on this value, it rationally adjusts the total torque demand of the vehicle, redistributing the adjusted total torque demand to the remaining normal motors while ensuring safe vehicle operation. This maintains the vehicle's basic driving capability and ensures that the vehicle will not break down due to the failure of a single or multiple motors during mining operations, significantly improving the continuity of vehicle operations and the overall transportation efficiency of the mine.

[0058] In summary, this embodiment, through the complete implementation of an integrated drive and energy recovery control system, achieves several core technological breakthroughs and comprehensive performance improvements in the practical application of large-tonnage mining dump trucks in open-pit mines. The four-motor coaxial coupling drive architecture completely breaks through the power limit of a single motor, and the superimposed torque output perfectly meets the traction requirements of extreme working conditions such as fully loaded climbing and starting on slippery surfaces. The fixed-ratio reduction gearbox replaces the traditional multi-speed gearbox, completely eliminating power interruption during gear shifts and completely avoiding the risks of sudden speed drops, impact jerking, and slippage on slopes, significantly improving driving safety and passenger comfort. The overall system is comprehensively superior to traditional mining dump truck drive systems in terms of power performance, energy efficiency, braking safety, maintenance costs, and operational efficiency, fully meeting the needs of large-scale, continuous, and high-intensity transportation operations in open-pit mines, and powerfully promoting the high-quality development of the mining dump truck industry towards electrification, intelligence, efficiency, and greening.

[0059] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. An integrated drive and energy recovery control system for mining dump trucks, characterized in that, The system includes: an energy source module, a four-motor drive module, a transmission and braking module, a high-voltage power distribution module, and a vehicle control module; The energy source module is used to provide the electrical energy required for the operation of the vehicle and to output electrical energy to the high-voltage power distribution module; The high-voltage power distribution module is used to realize the distribution and safety protection of high-voltage power, and to distribute power to the four-motor drive module; The four-motor drive module is used to convert electrical energy into mechanical energy and realize the coordinated output of multiple motors, outputting mechanical energy to the transmission and braking module; The transmission braking module is used to transmit power and provide braking capability to drive the wheels to rotate. The vehicle control module is used to realize the integrated and coordinated control of various subsystems. It interacts bidirectionally with the energy source module, the four-motor drive module, the transmission and braking module, and the high-voltage power distribution module. It receives the operating status data of each module, generates and sends control commands according to the vehicle operating conditions and driver operation commands, and completes the coordinated operation of drive torque distribution control, electric braking and hydraulic braking coordinated control, energy recovery control and range-extending operation mode switching control. The four-motor drive module includes four permanent magnet synchronous drive motors and four independent drive motor controllers. The four drive motors are arranged symmetrically, and their output shafts are coaxially coupled to the same coupling output shaft through rigid couplings. Each drive motor controller controls the operating state of one drive motor, receives torque commands sent by the vehicle control module, and adjusts the output torque and speed of the drive motor. The output torque of the four drive motors is centrally transmitted to the transmission and braking module through the coupling shaft to achieve the superposition output of the torque of multiple motors. The transmission braking module includes a fixed-ratio planetary gear reducer, a drive shaft, and a high-load-bearing wet brake drive axle. The input shaft of the fixed-ratio planetary gear reducer is connected to the coupling output shaft of the four-motor drive module. The output shaft of the fixed-ratio planetary gear reducer is connected to the drive shaft. The drive shaft is connected to the input shaft of the main reducer of the high-load-bearing wet brake drive axle. The high-load-bearing wet brake drive axle integrates a multi-plate fully hydraulic wet brake. The friction plates of the fully hydraulic wet brake are made of copper-based powder metallurgy material and are immersed in special cooling oil.

2. The integrated drive and energy recovery control system for a mining dump truck according to claim 1, characterized in that, The vehicle control module performs the following operations when distributing drive torque: Collect signals for accelerator pedal opening, vehicle speed, battery SOC, motor speed, and motor temperature; Based on the current efficiency characteristics of each drive motor, the total torque demand of the vehicle is calculated using a four-motor optimal torque allocation algorithm. The algorithm formula is as follows: ,in This represents the total torque required by the entire vehicle. Let be the efficiency weighting coefficient for the i-th drive motor. This represents the current maximum allowable output torque of the i-th drive motor; The required torque of each drive motor is set as follows: It then sends the torque command to the corresponding drive motor controller, monitors the actual output torque of each drive motor in real time, and dynamically corrects the torque distribution result.

3. The integrated drive and energy recovery control system for a mining dump truck according to claim 1, characterized in that, The vehicle control module performs the following operations when performing coordinated control of electric braking and hydraulic braking: Collect signals of brake pedal opening, vehicle speed, battery SOC, and motor speed, and calculate the total braking force requirement of the vehicle based on the collected signals; Determine whether the battery SOC is below the preset upper limit and whether the motor speed is within the allowable range for power generation; When the judgment result is yes, the maximum available electric braking force is calculated using the electro-hydraulic braking force distribution algorithm. The algorithm formula is as follows: ,in For the total braking force requirements of the entire vehicle, The electric motor is the power source, and μ is the hydraulic braking output coefficient. To maximize the hydraulic braking force of the wet brake, the electric braking force is preferentially allocated to the four drive motors. When the electric braking force is less than the total braking force requirement, the remaining braking force requirement is calculated, and a hydraulic braking command is sent to the transmission braking module, so that the remaining braking force is provided by the fully hydraulic wet brake.

4. The integrated drive and energy recovery control system for mining dump trucks according to claim 1, characterized in that, The energy source module includes two configurations: a pure electric energy source and a range-extending energy source. The pure electric energy source consists of a modular high-capacity power battery pack, which adopts a standardized module design. The range-extending energy source consists of a modular high-capacity power battery pack and a range extender assembly connected in parallel. The range extender assembly consists of a high-horsepower diesel engine and a high-power range extender coaxially connected. The electrical energy output by the range extender assembly is directly fed into the high-voltage DC bus.

5. The integrated drive and energy recovery control system for a mining dump truck according to claim 4, characterized in that, The vehicle control module performs the following operations when switching between range-extended operation modes: Collect battery SOC, vehicle power demand, and range extender operating status signals. When the battery SOC is higher than the first preset threshold and the vehicle power demand is less than the battery's maximum allowable discharge power, control the engine and range extender to stop and switch to pure electric drive mode. When the battery SOC is lower than the second preset threshold or the vehicle's required power is greater than the battery's maximum allowable discharge power, the range extender assembly is activated and switched to range extender drive mode. When the vehicle's required power exceeds the maximum output power of the range extender assembly, a range extender power coupling algorithm controls the coordinated output of dual energy sources. The algorithm formula is as follows: ,in For the power required by the whole vehicle, Where λ is the maximum output power of the battery, and λ is the output weighting coefficient of the range extender. To achieve the maximum output power of the range extender assembly, the power battery pack and the range extender assembly simultaneously output electrical energy, switching to a powerful power mode.

6. The integrated drive and energy recovery control system for a mining dump truck according to claim 1, characterized in that, The high-voltage power distribution module includes a high-voltage distribution box, which integrates a main contactor, a pre-charge contactor, a fuse, a current sensor, a voltage sensor, and an insulation monitoring unit. The input end of the high-voltage distribution box is connected to the energy source module, and the output end is connected to the controllers of four drive motors respectively. According to the instructions of the vehicle control module, the high-voltage distribution box completes the on-off control and distribution of power, and at the same time collects current, voltage and insulation status signals and sends them to the vehicle control module.

7. The integrated drive and energy recovery control system for a mining dump truck according to claim 1, characterized in that, The vehicle control module performs the following operations when performing motor fault redundancy control: The system collects the motor operating status and fault signals sent by each drive motor controller in real time. When a fault is detected in any one or more drive motors, the faulty motor is marked and the transmission of torque commands to the faulty motor is stopped. Recalculate the maximum total output torque that the remaining normal motors can provide, and adjust the total torque required by the vehicle based on the remaining maximum total output torque. The adjusted total torque demand is redistributed to the remaining normal motors to maintain vehicle operation.

8. The integrated drive and energy recovery control system for a mining dump truck according to claim 1, characterized in that, The vehicle control module includes a vehicle controller (VCU), a motor controller (MCU), a battery management system (BMS), and a brake controller (BCU). The VCU communicates with the MCU, BMS, and BCU via a CAN bus. The MCU collects the speed, torque, and temperature operating parameters of the drive motor and sends them to the VCU. The BMS collects the voltage, current, temperature, and SOC parameters of the power battery pack and sends them to the VCU. The BCU collects the brake pedal opening and brake pressure operating parameters and sends them to the VCU.

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