阅读说明：本技术 基于坡度识别的混联式宽体自卸车的控制系统和方法 (Gradient identification-based control system and method for series-parallel wide-body dump truck ) 是由 李昭 赵荣 庞亚娜 胥帆 何湘 仝梦炜 王小青 于 2019-10-12 设计创作，主要内容包括：本发明公开了一种基于坡度识别的混联式宽体自卸车的控制系统,其包括：第一动力机构,其包括主驱电机和主驱电机控制器；第二动力机构,其包括内燃机、内燃机控制器、ISG电机以及ISG电机控制器；动力电池,其与主驱电机控制器和ISG电机控制器连接；整车控制器,其与主驱电机控制器、内燃机控制器、ISG电机控制器、电磁离合器控制器、变速箱控制器以及动力电池通过总线通讯连接。本发明在增程式和并联式方案的基础上,提出了一种混联式宽体自卸车的控制系统,使内燃机一直处于高效经济区工作,在提高车辆的动力性的同时,实现明显的节油效果。(The invention discloses a control system of a series-parallel wide-body dump truck based on gradient identification, which comprises: the first power mechanism comprises a main drive motor and a main drive motor controller; the second power mechanism comprises an internal combustion engine, an internal combustion engine controller, an ISG motor and an ISG motor controller; the power battery is connected with the main drive motor controller and the ISG motor controller; and the vehicle control unit is in communication connection with the main drive motor controller, the internal combustion engine controller, the ISG motor controller, the electromagnetic clutch controller, the gearbox controller and the power battery through a bus. The invention provides a control system of a series-parallel wide-body dumper on the basis of a range-extending scheme and a parallel scheme, so that an internal combustion engine always works in a high-efficiency economic area, and the obvious oil-saving effect is realized while the dynamic property of a vehicle is improved.)

1. Control system of series-parallel connection formula wide-bodied tipper based on slope discernment, its characterized in that, it includes:

the first power mechanism comprises a main drive motor and a main drive motor controller; the main drive motor is connected with a middle and rear drive axle of the vehicle through a gearbox and provides driving force for the middle and rear drive axle;

the second power mechanism comprises an internal combustion engine, an internal combustion engine controller, an ISG motor and an ISG motor controller, wherein the internal combustion engine is connected with the ISG motor, and the ISG motor is connected with the main drive motor through an electromagnetic clutch;

the power battery is connected with the main drive motor controller and the ISG motor controller;

the whole vehicle controller is in communication connection with the main drive motor controller, the internal combustion engine controller, the ISG motor controller, the electromagnetic clutch controller, the gearbox controller and the power battery through a bus;

the vehicle control unit acquires a real-time vehicle gradient value R in real time, and the real-time vehicle gradient value R is filtered to obtain a vehicle gradient value i; calculating to obtain a vehicle load G through a running equation of vehicle dynamics, judging a vehicle load state by a vehicle controller, and when G is less than G0, the vehicle load state is an unloaded state; when G is larger than or equal to G1, the vehicle load state is a full load state; when G0 is less than or equal to G < G1, the vehicle load state at the previous moment is maintained; g0 and G1 are both preset vehicle loads, and G0< G1;

when the vehicle is in an idle state and i is larger than 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to consume the electric quantity of the power battery, provides driving force for driving a middle rear axle, controls the internal combustion engine to drive the ISG motor to work, converts the kinetic energy of the internal combustion engine into electric energy and charges the power battery; when the vehicle is in an idle state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to output reverse braking torque, charges the power battery through the main drive motor controller, detects the SOC value of the power battery and the allowable charging power of the battery, analyzes the braking recovery power output by the main drive motor and the allowable charging power of the battery, and adjusts the power generation power of the internal combustion engine and the ISG motor; when the vehicle is in a full-load state, the vehicle control unit controls the electromagnetic clutch to be in a closed state, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft, and provides driving force for driving a middle rear axle; when the vehicle is in a full-load state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a closed state, and when the vehicle control unit detects that the braking deceleration a of the vehicle is less than or equal to a1, the vehicle control unit controls the main drive motor to output braking torque; when a is more than a1, the vehicle control unit controls the main drive motor to brake and controls the internal combustion engine to start the exhaust braking function; when a is more than a2, the vehicle controller controls the main drive motor to brake, and simultaneously controls the internal combustion engine to start exhaust braking and a vehicle alarm to prompt a driver to step on a brake pedal; a1 and a2 are both preset brake deceleration thresholds, and a 1< a 2.

2. The control system of the series-parallel wide-body dump truck based on gradient identification as claimed in claim 1, further comprising a dual-axis tilt sensor fixedly arranged on a frame of the vehicle, wherein the dual-axis tilt sensor is configured to collect gradient data R of the vehicle and send the gradient data R to the vehicle controller through a CAN bus network.

3. The gradient identification-based control system of the series-parallel wide-body dump truck according to claim 2, wherein an input end of the gearbox is connected with a shaft extension end of the main drive motor, and an output end of the gearbox is connected with a transmission shaft of a driving middle rear axle of the vehicle.

4. The gradient identification-based control system of the series-parallel wide-body dump truck as claimed in claim 3, wherein the transmission and the driving middle and rear axles, the main drive motor and the transmission, the electromagnetic clutch and the main drive motor and the ISG motor, and the ISG motor and the internal combustion engine are all mechanically connected.

5. The control system of the gradient identification-based series-parallel wide-body dump truck as claimed in claim 4, wherein the power battery is connected with the ISG motor controller and the main drive motor controller through high-voltage cables.

6. The control system of the gradient identification-based series-parallel wide-body dump truck according to claim 1, wherein the bus communication is CAN bus communication, which comprises two-channel CAN bus communication; the internal combustion engine controller, the power battery and the vehicle control unit form one of the CAN bus communication channels; the main drive motor controller, the ISG motor controller, the electromagnetic clutch controller, the gearbox controller and the vehicle control unit form another channel CAN bus communication.

7. The gradient identification-based control system of the series-parallel wide-body dump truck as claimed in claim 1, wherein the real-time gradient value R of the vehicle is processed by a first-order inertial filtering method, wherein the time constant determination method of the filter is as follows: comparing the slope value R0 obtained at the last sampling moment, wherein the real-time slope value obtained at the moment is R, when the absolute value of R-R0 is more than or equal to a, the time constant of the filter is set to be T1, and when the absolute value of R-R0 is more than or equal to b, the time constant of the filter is set to be T2; when R-R0| ≧ c, the filter time constant is set to T3, a < b < c, T1< T2< T3; the time interval between the last sampling moment and this moment is 0.1 s.

8. The gradient identification-based control system of the series-parallel wide-body dump truck as claimed in claim 1, wherein the opening degree of an accelerator pedal of the vehicle is obtained by acquiring a dual-analog accelerator pedal signal by a vehicle controller, and calibrating and filtering the signal; the vehicle braking deceleration is acquired by a vehicle controller, and is acquired after time integration; and the SOC value of the power battery is acquired from CAN bus communication by the vehicle control unit.

9. The control system of the gradient identification-based series-parallel wide-body dump truck according to claim 8, wherein the running equation of the vehicle dynamics is as follows:

F_q-(F_i+F_f+F_w)＝m·a

wherein, F_qAs a driving force, F_iAs ramp resistance, F_WIs wind resistance, m is the vehicle mass, a is the vehicle acceleration, T_qFor driving the torque, i_gTo the speed ratio of the gearbox, i₀For the middle and rear axle speed ratio, r is the tire radius, η is the driveline efficiency, i is the finished vehicle grade, f is the rolling resistance coefficient, where 0.03, v_tThe value of the vehicle speed v at this moment_t-1The vehicle speed value of the whole vehicle at the previous moment is delta t, and the time interval of vehicle speed sampling is 0.1 s.

10. The control method of the series-parallel wide-body dump truck based on the gradient identification as claimed in any one of claims 1 to 9, wherein a vehicle control unit acquires a real-time gradient value R of the vehicle in real time, and the real-time gradient value R of the vehicle is filtered to obtain a gradient value i of the vehicle; calculating to obtain a vehicle load G through a running equation of vehicle dynamics, judging a vehicle load state by a vehicle controller, and when G is less than G0, the vehicle load state is an unloaded state; when G is larger than or equal to G1, the vehicle load state is a full load state; when G0 is less than or equal to G < G1, the vehicle load state at the previous moment is maintained; wherein G0 and G1 are both preset vehicle loads, and G0< G1;

when the vehicle is in an idle state and i is larger than 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to consume the electric quantity of the power battery, provides driving force for driving a middle rear axle, controls the internal combustion engine to drive the ISG motor to work, converts the kinetic energy of the internal combustion engine into electric energy and charges the power battery;

when the vehicle is in an idle state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to output reverse braking torque, charges the power battery through the main drive motor controller, detects the SOC value of the power battery and the allowable charging power of the battery, analyzes the braking recovery power output by the main drive motor and the allowable charging power of the battery, and adjusts the power generation power of the internal combustion engine and the ISG motor;

when the vehicle is in a full-load state, the vehicle control unit controls the electromagnetic clutch to be closed, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft, and provides driving force for driving the middle and rear axles;

when the vehicle is in a full-load state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, and the vehicle control unit detects that the braking deceleration a of the vehicle is less than or equal to a1, the vehicle control unit controls the main drive motor to output braking torque; when a is more than a1, the vehicle control unit controls the main drive motor to brake and controls the internal combustion engine to start the exhaust braking function; when a is more than a2, the vehicle controller controls the main drive motor to brake, and simultaneously controls the internal combustion engine to start exhaust braking and a vehicle alarm to prompt a driver to step on a brake pedal; a1 and a2 are both preset brake deceleration thresholds, and a 1< a 2.

Technical Field

The invention relates to the technical field of hybrid engineering vehicles. More particularly, the invention relates to a control system and method for a series-parallel wide-body dump truck based on gradient identification.

Background

The mining wide-body dump truck has the application scenes of coal mines, sand, stone, aggregate mines and other open mines generally, and has the working conditions that the transportation distance is short, the gradient change of a transportation road is large, the transportation route is fixed and repeated, and in order to respond to the modern green environment-friendly, energy-saving and emission-reduction calls, the dump truck mostly adopts a parallel hybrid drive system to improve the dynamic property and the fuel economy of the vehicle, the drive mode of the hybrid drive system comprises a pure electric drive mode, an engine drive mode and a hybrid drive mode, and the switching of the modes is the key of the hybrid power energy-saving and emission-reduction dump truck; in the prior art, the vehicle speed is mostly used as the basis for mode switching, and due to the working condition characteristics of the dump truck, the load condition of each driving force cannot be accurately reflected in real time only depending on the vehicle speed, so that the improvement of the dynamic property and the fuel economy of the vehicle is limited; in addition, the dump truck has higher requirement on braking of the whole truck due to larger inertia of the dump truck, and the planning and the regulation of a fresh braking system in the prior art cause that the speed controllability is poorer and the energy recovery rate is lower in the process of descending a slope of a heavy truck.

Disclosure of Invention

An object of the present invention is to solve at least the above problems and to provide at least the advantages described later.

The invention also aims to provide a control system of the series-parallel wide-body dump truck based on gradient identification, which provides the control system of the series-parallel dump truck on the basis of a range-extending scheme and a parallel scheme, so that an internal combustion engine always works in a high-efficiency economic area, and the obvious oil-saving effect is realized while the dynamic property of a vehicle is improved.

The invention also aims to provide a control method of the series-parallel type wide-body dump truck based on gradient identification, and provides the control method of the series-parallel type new energy wide-body dump truck based on gradient identification, so that the vehicle enters an electric braking mode in the downhill process to recover electric energy, a driving motor is driven to assist an internal combustion engine to jointly output driving force when a heavy load goes uphill, the internal combustion engine is always operated in a high-efficiency economic area through an energy optimization strategy of a vehicle control unit, and the obvious oil saving effect is realized while the dynamic property of the vehicle is improved.

To achieve these objects and other advantages and in accordance with the purpose of the invention, a control system of a series-parallel type wide-body dump truck based on slope recognition includes:

the first power mechanism comprises a main drive motor and a main drive motor controller; the main drive motor is connected with a middle and rear drive axle of the vehicle through a gearbox and provides driving force for the middle and rear drive axle;

the second power mechanism comprises an internal combustion engine, an internal combustion engine controller, an ISG motor and an ISG motor controller, wherein the internal combustion engine is connected with the ISG motor, and the ISG motor is connected with the main drive motor through an electromagnetic clutch;

the power battery is connected with the main drive motor controller and the ISG motor controller;

the whole vehicle controller is in communication connection with the main drive motor controller, the internal combustion engine controller, the ISG motor controller, the electromagnetic clutch controller, the gearbox controller and the power battery through a bus;

the vehicle control unit acquires a real-time vehicle gradient value R in real time, and the real-time vehicle gradient value R is filtered to obtain a vehicle gradient value i; calculating to obtain a vehicle load G through a running equation of vehicle dynamics, judging a vehicle load state by a vehicle controller, and when G is less than G0, the vehicle load state is an unloaded state; when G is larger than or equal to G1, the vehicle load state is a full load state; when G0 is less than or equal to G < G1, the vehicle load state at the previous moment is maintained; g0 and G1 are both preset vehicle loads, and G0< G1;

when the vehicle is in an idle state and i is larger than 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to consume the electric quantity of the power battery, provides driving force for driving a middle rear axle, controls the internal combustion engine to drive the ISG motor to work, converts the kinetic energy of the internal combustion engine into electric energy and charges the power battery; when the vehicle is in an idle state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to output reverse braking torque, charges the power battery through the main drive motor controller, detects the SOC value of the power battery and the allowable charging power of the battery, analyzes the braking recovery power output by the main drive motor and the allowable charging power of the battery, and adjusts the power generation power of the internal combustion engine and the ISG motor; when the vehicle is in a full-load state, the vehicle control unit controls the electromagnetic clutch to be in a closed state, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft, and provides driving force for driving a middle rear axle; when the vehicle is in a full-load state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a closed state, and when the vehicle control unit detects that the braking deceleration a of the vehicle is less than or equal to a1, the vehicle control unit controls the main drive motor to output braking torque; when a is more than a1, the vehicle control unit controls the main drive motor to brake and controls the internal combustion engine to start the exhaust braking function; when a is more than a2, the vehicle controller controls the main drive motor to brake, and simultaneously controls the internal combustion engine to start exhaust braking and a vehicle alarm to prompt a driver to step on a brake pedal; a1 and a2 are both preset brake deceleration thresholds, and a 1< a 2.

Preferably, the control system of the series-parallel wide-body dump truck based on gradient identification further comprises a double-shaft inclination angle sensor which is fixedly arranged on a frame of the vehicle and is used for acquiring gradient data R of the vehicle and sending the gradient data to the vehicle control unit through a CAN bus network.

Preferably, in the control system of the series-parallel wide-body dump truck based on gradient identification, the input end of the gearbox is connected with the shaft extension end of the main drive motor, and the output end of the gearbox is connected with a transmission shaft of a driving middle rear axle of a vehicle.

Preferably, in the control system of the series-parallel wide-body dump truck based on gradient identification, the transmission and the driving middle rear axle, the main drive motor and the transmission, the electromagnetic clutch and the main drive motor and the ISG motor, and the ISG motor and the internal combustion engine are all mechanically connected.

Preferably, in the control system of the series-parallel wide-body dump truck based on gradient identification, the power battery is connected with the ISG motor controller and the main drive motor controller through high-voltage cables.

Preferably, in the control system of the series-parallel wide-body dump truck based on gradient identification, the bus communication is CAN bus communication, and comprises two-channel CAN bus communication; the internal combustion engine controller, the power battery and the vehicle control unit form one of the CAN bus communication channels; the main drive motor controller, the ISG motor controller, the electromagnetic clutch controller, the gearbox controller and the vehicle control unit form another channel CAN bus communication.

Preferably, in the control system of the series-parallel wide-bodied dump truck based on gradient identification, the real-time gradient value R of the vehicle is processed by a first-order inertial filtering method, wherein the time constant determination method of the filter is as follows: comparing the slope value R0 obtained at the last sampling moment, wherein the real-time slope value obtained at the moment is R, when the absolute value of R-R0 is more than or equal to a, the time constant of the filter is set to be T1, and when the absolute value of R-R0 is more than or equal to b, the time constant of the filter is set to be T2; when R-R0| ≧ c, the filter time constant is set to T3, a < b < c, T1< T2< T3; the time interval between the last sampling moment and this moment is 0.1 s.

Preferably, in the control system of the parallel-series wide-body dump truck based on gradient identification, the opening degree of the accelerator pedal of the vehicle is acquired by a vehicle controller and is obtained after calibration and filtering; the vehicle braking deceleration is acquired by a vehicle controller, and is acquired after time integration; and the SOC value of the power battery is acquired from CAN bus communication by the vehicle control unit.

Preferably, in the control system of the series-parallel wide-body dump truck based on gradient identification, the running equation of the vehicle dynamics is as follows:

F_q-(F_i+F_f+F_w)＝m·a

wherein, F_qAs a driving force, F_iAs ramp resistance, F_WIs wind resistance, m is the vehicle mass, a is the vehicle acceleration, T_qFor driving the torque, i_gTo the speed ratio of the gearbox, i₀For the middle and rear axle speed ratio, r is the tire radius, η is the driveline efficiency, i is the finished vehicle grade, f is the rolling resistance coefficient, where 0.03, v_tThe value of the vehicle speed v at this moment_t-1The vehicle speed value of the whole vehicle at the previous moment is delta t, and the time interval of vehicle speed sampling is 0.1 s.

The invention also provides a control method of the series-parallel wide-body dump truck based on gradient identification, wherein a vehicle control unit acquires the real-time gradient value R of the vehicle in real time, and the real-time gradient value R of the vehicle is filtered to obtain a gradient value i of the vehicle; calculating to obtain a vehicle load G through a running equation of vehicle dynamics, judging a vehicle load state by a vehicle controller, and when G is less than G0, the vehicle load state is an unloaded state; when G is larger than or equal to G1, the vehicle load state is a full load state; when G0 is less than or equal to G < G1, the vehicle load state at the previous moment is maintained; wherein G0 and G1 are both preset vehicle loads, and G0< G1;

when the vehicle is in an idle state and i is larger than 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to consume the electric quantity of the power battery, provides driving force for driving a middle rear axle, controls the internal combustion engine to drive the ISG motor to work, converts the kinetic energy of the internal combustion engine into electric energy and charges the power battery;

when the vehicle is in an idle state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to output reverse braking torque, charges the power battery through the main drive motor controller, detects the SOC value of the power battery and the allowable charging power of the battery, analyzes the braking recovery power output by the main drive motor and the allowable charging power of the battery, and adjusts the power generation power of the internal combustion engine and the ISG motor;

when the vehicle is in a full-load state, the vehicle control unit controls the electromagnetic clutch to be closed, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft, and provides driving force for driving the middle and rear axles;

when the vehicle is in a full-load state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, and the vehicle control unit detects that the braking deceleration a of the vehicle is less than or equal to a1, the vehicle control unit controls the main drive motor to output braking torque; when a is more than a1, the vehicle control unit controls the main drive motor to brake and controls the internal combustion engine to start the exhaust braking function; when a is more than a2, the vehicle controller controls the main drive motor to brake, and simultaneously controls the internal combustion engine to start exhaust braking and a vehicle alarm to prompt a driver to step on a brake pedal; a1 and a2 are both preset brake deceleration thresholds, and a 1< a 2.

The invention has the following beneficial effects:

1. the first power mechanism is a motor with new energy and is used as a main drive, the second power mechanism is an auxiliary drive of an internal combustion engine, and the first power mechanism and the second power mechanism are connected to a driving shaft through an electromagnetic clutch when the auxiliary drive is needed and are used for driving a middle rear axle of a vehicle to drive the vehicle to run; the vehicle control unit is used for switching the driving modes of the vehicle in real time and accurately based on the gradient of the vehicle and the load state of the vehicle, so that the energy utilization rate of the power mechanisms is maximized on the basis of ensuring the stable and safe running of the vehicle, the waste of energy is avoided, the energy consumption is reduced, and the service life of each power mechanism is prolonged; in addition, the single-shaft drive can only use one gearbox, so that the braking of the vehicle has systematic adjustability when the vehicle is in a fully loaded load state, the braking mode is intelligently switched according to real-time road conditions and vehicle conditions, the electric braking is firstly performed, the exhaust braking is secondly performed, and the pedal braking is finally involved, so that the vehicle speed can be controlled, and the electric quantity can be recovered as much as possible when the whole vehicle is in a downhill process of heavy vehicle;

2. the core of the control method for the driving mode of the hybrid vehicle is a gradient recognition algorithm, so that the load of the whole vehicle can be obtained and further applied to algorithms such as a whole vehicle mode switching algorithm, electric brake recovery and the like, when the vehicle is in an idle state and the vehicle goes up a slope, the vehicle enters a range-extended driving mode, the electric quantity of a power battery consumed by a main driving motor is independently used as driving force, an internal combustion engine and an ISG motor are mechanically connected to form a range extender, and the internal combustion engine drives the ISG motor to supplement the charging quantity for the power battery; when the vehicle is in an idle state and the vehicle goes downhill, the vehicle enters an electric braking recovery mode, a main drive motor brakes and recovers energy, a power battery is charged through a motor driver, and the internal combustion engine and the ISG motor also generate power according to real-time working condition dynamic power; when the vehicle is in full load and the vehicle goes up a slope, the vehicle enters a hybrid driving mode, an electromagnetic clutch is closed, a first power mechanism and a second power mechanism are connected to the same driving shaft and are used for driving a middle rear axle of the vehicle, a main driving motor is coaxially connected with an internal combustion engine and outputs driving force together to drive the vehicle to run, when the vehicle is in full load and the vehicle goes down the slope, a controller calls an intelligent braking system under the hybrid driving mode, three braking modes are switched according to the braking deceleration of the vehicle, the electric braking is firstly performed, the exhaust braking is secondly performed, and finally pedal braking is intervened, so that the speed of the whole vehicle can be controlled and the electric quantity can be recovered as much as possible in the process of going down the slope;

3. in the hybrid driving mode, the driving motor and the auxiliary internal combustion engine can output driving force together in the hybrid mode in the process of uphill of a heavy vehicle, so that the engine always works in a high-efficiency area, and the oil consumption is reduced; in the downhill process, the electric braking mode realizes the speed slowing function, and meanwhile, the recovered electric energy is stored and used for a driving motor in the uphill process; the invention has been successfully implemented on the sample vehicle, and can meet the requirement of complex road conditions in a mining area through actual mining area tests, and compared with the traditional fuel oil vehicle, the power performance is obviously improved, the fuel saving rate is obvious, and the fuel saving rate of the invention can reach 20%.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention.

Drawings

Fig. 1 is a schematic diagram of the structure and principle of the control system of the present invention.

Detailed Description

The present invention is further described in detail below with reference to the drawings and examples so that those skilled in the art can practice the invention with reference to the description.

It will be understood that terms such as "having," "including," and "comprising," as used herein, do not preclude the presence or addition of one or more other elements or groups thereof.

It is to be noted that the experimental methods described in the following embodiments are all conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified.

In the description of the present invention, the terms "lateral", "longitudinal", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, are only for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be construed as limiting the present invention.

As shown in fig. 1, the present invention provides a control system for a series-parallel wide-bodied dump truck based on gradient identification, which comprises:

the first power mechanism comprises a main drive motor and a main drive motor controller MCU; the main drive motor is connected with a middle drive rear axle of the vehicle through a gearbox ATM and provides driving force for the middle drive rear axle;

the second power mechanism comprises an internal combustion engine, an internal combustion engine controller ECU, an ISG motor and an ISG motor controller GMCU, wherein the internal combustion engine is connected with the ISG motor, and the ISG motor is connected with the main drive motor through an electromagnetic clutch; the electromagnetic clutch can be replaced by a dry clutch structure with an automatic control function;

the power battery BMS is connected with the main drive motor controller MCU and the ISG motor controller GMCU;

the whole vehicle controller is in communication connection with the main drive motor controller MCU, the internal combustion engine controller ECU, the ISG motor controller GMCU, the electromagnetic clutch controller CCU, the gearbox controller TCU and the power battery BMS through buses;

the vehicle control unit acquires a real-time vehicle gradient value R in real time, and the real-time vehicle gradient value R is filtered to obtain a vehicle gradient value i; calculating to obtain a vehicle load G through a running equation of vehicle dynamics, judging a vehicle load state by a vehicle controller, and when G is less than G0, the vehicle load state is an unloaded state; when G is larger than or equal to G1, the vehicle load state is a full load state; when G0 is less than or equal to G < G1, the vehicle load state at the previous moment is maintained; g0 and G1 are both preset vehicle loads, and G0< G1;

when the vehicle is in an idle state and i is larger than 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to consume the electric quantity of the power battery, provides driving force for driving a middle rear axle, controls the internal combustion engine to drive the ISG motor to work, converts the kinetic energy of the internal combustion engine into electric energy and charges the power battery;

when the vehicle is in an idle state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to output reverse braking torque, charges the power battery through the main drive motor controller, detects the SOC value of the power battery and the allowable charging power of the battery, analyzes the braking recovery power output by the main drive motor and the allowable charging power of the battery, and adjusts the power generation power of the internal combustion engine and the ISG motor;

when the vehicle is in a full-load state, the vehicle control unit controls the electromagnetic clutch to be in a closed state, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft, and provides driving force for driving a middle rear axle;

when the vehicle is in a full-load state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, and the vehicle control unit detects that the braking deceleration a of the vehicle is less than or equal to a1, the vehicle control unit controls the main drive motor to output braking torque; when a is more than a1, the vehicle control unit controls the main drive motor to brake and controls the internal combustion engine to start the exhaust braking function; when a is more than a2, the vehicle controller controls the main drive motor to brake, and simultaneously controls the internal combustion engine to start exhaust braking and a vehicle alarm to prompt a driver to step on a brake pedal; a1 and a2 are both preset brake deceleration thresholds, and a 1< a 2.

In the technical scheme, on the basis of the extended-range and parallel schemes, the control system of the series-parallel dump truck is provided, so that the internal combustion engine always works in a high-efficiency economic area, and the obvious oil-saving effect is realized while the dynamic property of the vehicle is improved;

the range-extended motor is arranged, so that the kinetic energy of the internal combustion engine can be used as auxiliary driving force, and the range-extended motor can be driven to generate electricity, further the kinetic energy is converted into electric energy, and a power battery is charged; in the control system, the electromagnetic clutch is introduced, so that the main drive motor and the internal combustion engine form a hybrid working mode, and when the electromagnetic clutch is closed, the first power mechanism and the second power mechanism are positioned on the same driving shaft and act on the same gearbox, so that the braking mode can be intelligently and systematically controlled under the heavy-load downhill state of the vehicle, the vehicle speed can be controlled, and the electric quantity can be recovered as much as possible; the high efficiency, energy conservation and environmental protection of the dumper during operation are really realized.

In another technical scheme, the control system of the series-parallel wide-body dump truck based on gradient identification further comprises a double-shaft inclination angle sensor which is fixedly arranged on a frame of the vehicle and used for acquiring gradient data R of the vehicle and sending the gradient data to the vehicle control unit through a CAN bus network. The real-time gradient data of the vehicle can be accurately acquired through the double-shaft tilt angle sensor.

In another technical scheme, in the control system of the series-parallel wide-body dump truck based on gradient identification, the input end of the gearbox is connected with the shaft extension end of the main drive motor, and the output end of the gearbox is connected with a transmission shaft of a driving middle rear axle of a vehicle.

In another technical scheme, in the control system of the series-parallel wide-body dump truck based on gradient identification, the transmission and the driving middle rear axle, the main drive motor and the transmission, the electromagnetic clutch and the main drive motor and the ISG motor, and the ISG motor and the internal combustion engine are all mechanically connected.

In another technical scheme, in the control system of the series-parallel wide-body dump truck based on gradient identification, the power battery is connected with the ISG motor controller and the main drive motor controller through high-voltage cables.

In another technical scheme, in the control system of the series-parallel wide-body dump truck based on gradient identification, bus communication is CAN bus communication and comprises two-channel CAN bus communication; the internal combustion engine controller, the power battery and the vehicle control unit form one of the CAN bus communication channels; the main drive motor controller, the ISG motor controller, the electromagnetic clutch controller, the gearbox controller and the vehicle control unit form another channel CAN bus communication. The dual-channel CAN bus communication CAN improve the safety and efficiency of the CAN communication of the whole vehicle, reduce the bus load rate of a power source communication loop (one CAN bus), and realize the coordinated output of two power sources of an internal combustion engine and a driving motor and the communication and data exchange between other controllers.

In another technical scheme, in the control system of the series-parallel wide-body dump truck based on gradient identification, the real-time gradient value R of the vehicle is processed by adopting a first-order inertia filtering method, wherein the time constant determination method of the filter is as follows: comparing the slope value R0 obtained at the last sampling moment, wherein the real-time slope value obtained at the moment is R, when the absolute value of R-R0 is more than or equal to a, the time constant of the filter is set to be T1, and when the absolute value of R-R0 is more than or equal to b, the time constant of the filter is set to be T2; when R-R0| ≧ c, the filter time constant is set to T3, a < b < c, T1< T2< T3; the time interval between the last sampling moment and this moment is 0.1 s. The filtering process is performed to ensure continuity and stability of the gradient data.

In another technical scheme, in the control system of the series-parallel wide-body dump truck based on gradient identification, the opening degree of an accelerator pedal of a vehicle is acquired by a vehicle control unit, and a dual-analog accelerator pedal signal is obtained after calibration and filtering; the vehicle braking deceleration is acquired by a vehicle controller, and is acquired after time integration; and the SOC value of the power battery is acquired from CAN bus communication by the vehicle control unit.

In another technical solution, in the control system of the series-parallel wide-body dump truck based on gradient identification, a running equation of vehicle dynamics is as follows:

F_q-(F_i+F_f+F_w)＝m·a

wherein, F_qAs a driving force, F_iAs ramp resistance, F_WIs wind resistance, m is the vehicle mass, a is the vehicle acceleration, T_qFor driving the torque, i_gTo the speed ratio of the gearbox, i₀For the middle and rear axle speed ratio, r is the tire radius, η is the driveline efficiency, i is the finished vehicle grade, f is the rolling resistance coefficient, where 0.03, v_tThe value of the vehicle speed v at this moment_t-1The vehicle speed value of the whole vehicle at the previous moment is delta t, and the time interval of vehicle speed sampling is 0.1 s.

A control method of a series-parallel wide-body dump truck based on gradient identification is characterized in that a vehicle control unit acquires a real-time gradient value R of a vehicle in real time, and the real-time gradient value R of the vehicle is filtered to obtain a gradient value i of the vehicle; calculating to obtain a vehicle load G through a running equation of vehicle dynamics, judging a vehicle load state by a vehicle controller, and when G is less than G0, the vehicle load state is an unloaded state; when G is larger than or equal to G1, the vehicle load state is a full load state; when G0 is less than or equal to G < G1, the vehicle load state at the previous moment is maintained; wherein G0 and G1 are both preset vehicle loads, and G0< G1;

based on slope recognition, in combination with the vehicle load state, the ground drive mode of the vehicle is regulated:

a range-extending driving mode: when the vehicle is in an idle state and i is larger than 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to consume the electric quantity of the power battery, provides driving force for driving a middle rear axle, controls the internal combustion engine to drive the ISG motor to work, converts the kinetic energy of the internal combustion engine into electric energy and charges the power battery;

electric brake recovery mode: when the vehicle is in an idle state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be in a disconnected state, controls the main drive motor to output reverse braking torque, charges the power battery through the main drive motor controller, detects the SOC value of the power battery and the allowable charging power of the battery, analyzes the braking recovery power output by the main drive motor and the allowable charging power of the battery, and adjusts the power generation power of the internal combustion engine and the ISG motor; the vehicle control unit collects data of vehicle speed, gear of a gearbox and gradient of the whole vehicle in real time, calculates optimal electric braking torque, ensures continuity and smoothness of electric braking, and determines an initial value of the electric braking torque according to a vehicle dynamic balance equation as follows:

F_t＝F_i-F_f-F_w

in the above formula, F_tAs a driving force, F_iAs ramp resistance, F_WIs wind resistance, T_qIs moment of resistance, i_gTo the speed ratio of the gearbox, i₀The rear axle speed ratio is obtained, r is the tire radius, eta is the transmission system efficiency, G is the vehicle weight of the whole vehicle, i is the gradient of the whole vehicle, and f is the rolling resistance coefficient, wherein the value is 0.03;

hybrid drive mode: when the vehicle is in a full-load state, the vehicle control unit controls the electromagnetic clutch to be closed, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft, and provides driving force for driving the middle and rear axles; in the hybrid driving mode, when the torque required by a driver is smaller than the economic torque of the engine at the current rotating speed, the engine outputs the torque value required by the driver, the main driving motor outputs 0 torque, and the engine works in an economic area at the moment; when the driver demand torque is larger than the economic torque of the engine at the current rotating speed, the engine outputs an economic torque value at the current rotating speed, and the output value of the main drive motor is the difference value of the driver demand torque value and the economic torque value at the current rotating speed of the engine;

intelligent auxiliary braking system in hybrid drive mode: when the vehicle is in a full-load state, i is less than or equal to 0 and the opening degree of an accelerator pedal of the vehicle is 0, the vehicle control unit controls the electromagnetic clutch to be closed, connects the internal combustion engine, the ISG motor and the main drive motor to the same driving shaft and provides driving force for driving a middle rear axle; when the vehicle control unit detects that the vehicle braking deceleration a is less than or equal to a1, the vehicle control unit controls the main drive motor to output braking torque; when a is more than a1, the vehicle control unit controls the main drive motor to brake and controls the internal combustion engine to start the exhaust braking function; when a is more than a2, the vehicle controller controls the main drive motor to brake, and simultaneously controls the internal combustion engine to start exhaust braking and a vehicle alarm to prompt a driver to step on a brake pedal; a1 and a2 are both preset brake deceleration thresholds, and a 1< a 2. The coordinated action of the three braking modes is carried out according to the principle that the electric braking mode is prior, then exhaust braking is carried out, and finally vehicle pedal braking is intervened, so that the braking safety of the vehicle in the heavy-load downhill process is ensured, and the abrasion of a braking system of a main brake is effectively reduced while electric energy is recycled by the electric braking as much as possible.

In the technical scheme, the working state of the whole vehicle is divided into three modes according to the flowing direction of energy and by referring to the parameters such as the gradient data of the whole vehicle, the opening degree of an accelerator pedal, the opening degree of an active pedal, the speed of the whole vehicle, the SOC of a power battery and the like: firstly, in a range-extending driving mode, an internal combustion engine and an ISG motor are mechanically connected to form a range extender to charge a power battery, and a main driving motor consumes the electric energy of the power battery to drive a vehicle to run; the other is a braking recovery mode, the main drive motor brakes and recovers energy, the power battery is charged through the motor driver, and the internal combustion engine and the ISG motor also generate power according to real-time working condition dynamic power; the hybrid driving mode is adopted, the main driving motor consumes the electric energy of a power battery, and the power battery and the internal combustion engine jointly output driving force to drive the vehicle to run through the electromagnetic clutch; in a hybrid driving mode, when a heavy-duty vehicle goes downhill, the vehicle controller starts an intelligent auxiliary braking system to realize the system controllability of braking.

The number of apparatuses and the scale of the process described herein are intended to simplify the description of the present invention. Applications, modifications and variations of the present invention will be apparent to those skilled in the art.

While embodiments of the invention have been described above, it is not limited to the applications set forth in the description and the embodiments, which are fully applicable in various fields of endeavor to which the invention pertains, and further modifications may readily be made by those skilled in the art, it being understood that the invention is not limited to the details shown and described herein without departing from the general concept defined by the appended claims and their equivalents.