Summary of the invention
In view of the deficiencies of the prior art, the present invention proposes a kind of commercial vehicle electric auxiliary steering system control method, purposes
It is to provide specific method for the electronic assisted diversion control strategy of commercial vehicle.
The present invention is to solve its technical problem, is adopted the following technical scheme that
A kind of commercial vehicle electric auxiliary steering system control method, the system include electric power steering subsystem
(EPS), circulating ball type hydraulic power-assisted steering subsystem (HPS);The electric power steering subsystem (EPS) includes motor, turns round
Bar, input shaft, torque-angular transducer, worm type of reduction gearing, the hydraulic power-assisted steering subsystem (HPS) includes hydraulic
Control valve, hydraulic steering gear;The electric power steering subsystem (EPS) is arranged in circulating ball type hydraulic power-assisted steering subsystem
(HPS) input terminal, constitutes monolithic construction, electric boosted subsystem (EPS) controller according to driver's hand-power square or
Upper controller corner instruction control assist motor power-assisted size, and then be superimposed by worm type of reduction gearing with driver's hand-power
Afterwards or on independent role to the input terminal of circulating ball type hydraulic power-assisted steering subsystem (HPS), turn circulating ball type hydraulic booster
Hydraulic control valve in subsystem (HPS), which is opened, generates hydraulic booster;
Its main feature is that: the control method of the system the following steps are included:
Step 1: electric auxiliary steering system receives desired signal
Specifically include following procedure:
(1) steering wheel angle signal, hand torque signals and assist motor body temperature signal are acquired by sensor and are
System drive module temperature signal;
Electronic assisted diversion controller ECU receive speed signal that entire car controller sends, drive early warning enable signal,
Intelligent driving system enabling signal and target rotation angle track signal.
Step 2: electric auxiliary steering system bottom motor control
Specifically include following procedure:
(1) the judgement of system control model-switching module carries out analysis integrated;
(2) the closed-loop control of assist motor bottom torque-angle is carried out.
Step 3: realize driver under ring scene with fast power-assisted steering, steering wheel actively return just, middle position hand
Power, drives warning function at road bump filtering;Realize driver's lane holding, active steering angle tracking function not under ring scene
Energy;Realize emergency steering, electronic steering lock, motor overheat protector function.
The driver of the step 3 specifically includes following procedure with fast power-assisted steering function under ring scene:
(1) electronic control unit ECU acquires steering wheel hand-power square, speed and motor current signal in real time;
(2) realize that commercial vehicle low speed turns to function light, that high speed steering is sedate according to fast Power assisted control algorithm.
Steering wheel active return function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) ECU acquires steering wheel angle and driver's hand torque signals in real time;
(2) judge whether system has the initiative back positive status according to returning positive decision logic, if so, just controlling by actively returning
Algorithm processed realizes accurate and stable active return function.
Middle position hand-power function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) system acquires steering wheel angle, driver's hand-power square and speed signal in real time;
(2) realize that driver is to middle position hand-power demand difference under different speeds by middle position hand-power control algolithm
Function.
Road bump filtering function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) system real-time detection steering wheel angle signal and driver's hand torque signals;
(2) decision logic is filtered according to road bump and judge whether system is in road bump filtered model, if so, closing
Other control models are closed, control algolithm is filtered by road bump and inhibits the small amplitude jitter of steering wheel high frequency.
Driving warning function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) system receives the driving pre-warning signal that entire car controller comes;
(2) pre- by driving in the state of guaranteeing vehicle stabilization traveling and under the mode of the original working condition of assist motor
Alert control algolithm warns driver.
Active steering angle tracking function (comprising lane keep) of the driver of the step 3 not under ring scene is specific
Including following procedure:
(1) system receives the enabling signal and target rotation angle tracking signal that intelligent driving controller (entire car controller) issues;
(2) accurate tracking (lane holding) function of corner is realized by active corner tracking control algorithm.
Emergency turning function of the driver of the step 3 not under ring scene specifically includes following procedure:
(1) system acquisition steering wheel hand-power square and steering wheel angle signal;
(2), by emergency shift control algorithm, guarantee that in the case where hydraulic booster subsystem failure, vehicle is remained to according to driving
The person of sailing is intended to complete the steering operation of necessary number.
Electrical steering lock function of the driver of the step 3 not under ring scene, specifically includes following procedure:
(1) system receives vehicle and steals signal;
(2) under the premise of turning to intention without prejudice to driver, realize that vehicle is turning to by electronic steering lock control algolithm
Anti-theft function in subsystem level.
Electric motor protecting function of the driver of the step 3 not under ring scene specifically includes following procedure:
(1) system real-time detection motor body temperature signal and system drive module temperature signal;
(2) necessary overheat protector is carried out to motor and system by electric motor protecting control logic.
Advantages of the present invention effect
1, the present invention devises a kind of electric auxiliary steering system control taken into account under commercial vehicle someone and unmanned scene
It is electronic auxiliary to realize the commercial vehicle that driver is under ring scene, driver is not under ring scene in same system for method processed
Steering system control method is helped, two methods can arbitrarily switch.Using driver in ring rotating direction control method, can effectively mention
High driver's experience, enjoys the enjoyment of intelligent power-assisted pilot steering to the full;Using driver not in ring rotating direction control method, when
When driver feels tired or be not desired on the way to drive, steering wheel control can be given to unmanned steering system at any time, solved
The prior art of having determined is unmanned or manned, and the two cannot take into account, problem that cannot be complementary.
2, racing is answered under the commercial vehicle hydraulic booster failure based on electric auxiliary steering system that the invention proposes a kind of
To control strategy, electronic control unit carries out sentencing for hydraulic failure mode by acquisition driver's hand-power square and steering wheel angle
It is disconnected, then cancel the limitation of motor maximum power-assisted square, guarantees that in the case where hydraulic booster subsystem failure, vehicle is remained to according to driving
The person of sailing is intended to complete the steering operation of necessary number.
3, the present invention proposes a kind of driver fatigue early warning control based on electric auxiliary steering system, electronic control unit
ECU, which is received, drives pre-warning signal, and system gives assist motor additional rotation angle control instruction in the case where guaranteeing vehicle stabilization driving status,
Make steering wheel with certain frequency and amplitude vibration, tired warning is carried out to driver.
4, the present invention propose a kind of target rotation angle based on electric auxiliary steering system open loop frequency experimental results with
Track scheme directly can be used to compensation system in performance objective according to system open loop Frequency Response curve coupling collar shaping control strategy
Rub hysteresis phenomenon present in corner tracking, to realize accurate target rotation angle tracking effect.
Specific embodiment
A specific embodiment of the invention is described in detail with reference to the accompanying drawing.
1, commercial vehicle electric auxiliary steering system designs cause.Commercial vehicle electric auxiliary steering system refers to will be electric boosted
Turn to the system that subsystem and hydraulic power-assisted steering subsystem combine.Commercial vehicle electric auxiliary steering system is generally used for commercialization
The man-machine scene driven altogether of vehicle, it is described it is man-machine drive altogether be same vehicle both can be unmanned, can also be manned.It is commercial
Vehicle is since carrying quality is big, and steering resistence is big, and general motor steering power is unable to satisfy the requirement of the high-power steering of commercial vehicle,
Therefore, conventional commercial vehicle uses hydraulic steering system.But hydraulic steering system must rely on manual operation, cannot achieve intelligence
What is controlled is unmanned, and under the situation that current unmanned demand grows to even greater heights, conventional commercial vehicle can no longer meet nobody
The demand of driving.To meet the unmanned demand of commercial vehicle, conventional hydraulic steering system need to be combined with electric power steering,
Meet the needs of commercial vehicle high power load using its fluid-link steering subsystem, nothing is realized using its electric power steering subsystem
The demand that people drives.
2, the cause of present invention design driver's each function under ring scene.The present invention designs driver under ring scene
Each function be experience in order to improve driver, these experience are that conventional commercial vehicle cannot be given, because of tradition quotient
It uses mechanical-hydraulic steering system completely with vehicle and does not use intelligence system, thus cannot achieve intelligent control.For example, to improve
Driver's experience, the present invention devise driver under ring scene with fast servo steering system, it is so-called with fast power-assisted be exactly with
The difference of speed changes electric boosted size.For example, manipulation direction disk is turned to relative to high speed when driver's low speed is driven
It is larger to turn to encountered resistance, at this point, electric power steering subsystem is turned to using big power-assisted auxiliary driver, so that driving
Member similarly feels that comparison is light when low speed turns to, to improve the experience of driver.It is manipulated when driver's high speed is driven
Wheel steering, when higher due to speed, driver may feel the drift of steering wheel hair and be not easy to control, at this point, electronic help
Power turn to subsystem give steering wheel one lesser power-assisted, with meet speed it is very high when stable turning requirement, this measure is equally
It is the experience in order to improve driver.
3, the cause of present invention design driver's each function not under ring scene.Driver of the present invention is not in ring
Although scene also include driver people onboard, not manipulation direction disk in person, and given nothing steering wheel control
The scene of people's control loop, such case are also referred to as driver of the invention not in ring scene.The present invention devises driver not
Under ring scene active steering angle tracking function (comprising lane keep) etc., design these functions be applied not only to it is unmanned,
It is also used for driving on the way as driver because when a variety of causes is not easy to drive or need to drive auxiliary, steering wheel can be controlled
Power gives unmanned steering system at any time, automatically keeps lane, active steering angle tracking by unmanned steering system, thus
Solves the commercial vehicle of the prior art: the problem of perhaps complete pilot steering or unmanned, the two cannot be taken into account.
4, commercial vehicle electric auxiliary steering system overall structure.Attached drawing 1 is that this commercial vehicle electric auxiliary steering system is whole
Structural schematic diagram, including two parts in left and right, left-half are electric power steering subsystem (EPS), and right half part is circulation
Ball-type hydraulic power-assisted steering subsystem (HPS);The electric power steering subsystem (EPS) includes motor 1, torsion bar in Fig. 1
2, (when pilot steering, which is manned steering wheel shaft to input shaft 3;When unmanned, which is
Motor-driven steering wheel shaft), torque-angular transducer 4, worm type of reduction gearing 5;The hydraulic power-assisted steering subsystem
(HPS) include hydraulic control valve 6, hydraulic steering gear 7 in Fig. 1.The electric power steering subsystem (EPS) is arranged in circulation
The input terminal of ball-type hydraulic power-assisted steering subsystem (HPS) constitutes monolithic construction, electric boosted subsystem (EPS) control
Device processed passes through worm and gear according to driver's hand-power square or upper controller corner instruction control assist motor power-assisted size
Retarder with driver's hand-power be superimposed after or independent role to circulating ball type hydraulic power-assisted steering subsystem (HPS) input terminal
On, it opens the hydraulic control valve in circulating ball type hydraulic power-assisted steering subsystem (HPS) and generates hydraulic booster.It is described electronic to help
Power turns to subsystem (EPS) and is connect with circulating ball type hydraulic power-assisted steering subsystem (HPS) by spline.EPS is using non-contact
The torque-corner sensor acquisition steering wheel angle and driver's hand torque signals of formula, EPS assist motor use permanent magnet synchronous electric
Machine (PMSM), voltage rating 24V, motor output end are connected using claw elasticity shaft joint and the input terminal of worm screw.
As shown in Figure 10 it is commercial vehicle electric auxiliary steering system control strategy architecture diagram of the present invention, is based on the control plan
Slightly, the present invention devises a kind of commercial vehicle electric auxiliary steering system control method.
1, a kind of commercial vehicle electric auxiliary steering system control method, its main feature is that, the control method of the system include with
Lower step:
Step 1: electric auxiliary steering system receives desired signal, specifically includes following procedure:
(1) steering wheel angle signal, hand torque signals and assist motor body temperature signal are acquired according to sensor and are
System drive module temperature signal;
Electronic assisted diversion controller ECU receive speed signal that entire car controller sends, drive early warning enable signal,
Intelligent driving system enabling signal and target rotation angle track signal.
Step 2: electric auxiliary steering system bottom motor control specifically includes following procedure:
(1) the judgement of system control model-switching module is carried out analysis integrated;
(2) the closed-loop control of assist motor bottom torque-angle is carried out.
Step 3: realize driver under ring scene with fast power-assisted steering, steering wheel actively return just, middle position hand
Power, drives warning function at road bump filtering;Realize lane holding, active steering angle tracking of the driver not under ring scene
Function;Realize emergency steering, electronic steering lock, motor overheat protector function.
The driver of the step 3 specifically includes following procedure with fast power-assisted steering function under ring scene:
(1) electronic control unit ECU acquires steering wheel hand-power square, speed and motor current signal in real time;
(2) realize that commercial vehicle low speed turns to function light, that high speed steering is sedate according to fast Power assisted control algorithm.
Supplementary explanation:Referring to Fig.2, electronic control unit ECU acquires driver's hand torque signals T in real timehAnd speed signal
U, according to it is preset with fast power-assisted family of curves (tested repeatedly by electric auxiliary steering system testing stand or real train test,
Calibration obtains), desired assist motor size of current I is determined tabling look-up, by way of interpolationd;On the other hand, ECU is according to electricity
Sampling resistor acquires assist motor actual current size Ir in real time in machine drive module, and the period that setting electric current closed loop is adjusted is
100us realizes that the closed loop of current of electric is adjusted by PID control.It is final to realize the big power-assisted of low speed and the small assist characteristic of high speed, with
Meet commercial vehicle low speed ease of steering and high-speed handing stability requirement.
Steering wheel active return function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) ECU acquires steering wheel angle and driver's hand torque signals in real time;
(2) judge whether system has the initiative back positive status according to returning positive decision logic, if so, just controlling by actively returning
Algorithm processed realizes accurate and stable active return function.
Supplementary explanation:Refering to Fig. 3, electronic control unit ECU acquires steering wheel angle signal θ, driver's hand-power square in real time
Signal Th, rotary transform tensor system model judges algorithm first according to steering wheel angle θ and angular speedProduct it is positive and negative and square
To disk torque gradient grad (Th) start to change whether comprhensive deterministic system enters back positive status from non-zero to zero;With steering wheel return
Active rotary transform tensor target is used as (± 10 °) near to middle position;To guarantee optimal return performance, introduces back positive speed and make
For system rotary transform tensor constraint condition, i.e. control effect should make system just start back timing with lesser time positive speed to keep away
Exempt to driver hired roughneck, has biggish time positive speed to guarantee higher time positive precision when approaching back positive zero-bit.
Middle position hand-power function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) system acquires steering wheel angle, driver's hand-power square and speed signal in real time;
(2) realize that driver is to middle position hand-power demand difference under different speeds by middle position hand-power control algolithm
Function.
Road bump filtering function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) system real-time detection steering wheel angle signal and driver's hand torque signals;
(2) decision logic is filtered according to road bump and judge whether system is in road bump filtered model, if so, closing
Other control models are closed, control algolithm is filtered by road bump and inhibits the small amplitude jitter of steering wheel high frequency.
Supplementary explanation:Refering to Fig. 4, electronic control unit ECU acquires steering wheel angle signal θ, driver's hand-power square in real time
Signal Th, system model judges algorithm first to steering wheel angular signal θ, driver's hand torque signals ThCarry out spectrum signature point
Analysis judges whether system enters road bump filtered model, if so, by carrying out fault control (by being shorted motor three to motor
The mode of phase winding is realized) dissipate the energy of road bump generation, inhibit the high dither phenomenon of steering wheel, mitigates and drive
The physics and mental burden of member.
Driving warning function of the driver of the step 3 under ring scene specifically includes following procedure:
(1) system receives the driving pre-warning signal that entire car controller sends over;
(2) pre- by driving in the state of guaranteeing vehicle stabilization traveling and under the mode of the original working condition of assist motor
Alert control algolithm warns driver.
Supplementary explanation:Refering to Fig. 5, electronic control unit ECU acquires the driving pre-warning signal of entire car controller transmission in real time
Driving_Alert, under modes of warning, the guarantee original operating mode of current time system first is constant, is then ensuring vehicle
Under the premise of mode decision algorithm confirmation system does not enter driving modes of warning under the conditions of unstability system, one is added to assist motor
It is expected that corner is made steering wheel with certain frequency and amplitude vibration, is mentioned to driver by motor bottom angle closed-loop control
It wakes up and warns.
Active steering angle tracking function (comprising lane keep) of the driver of the step 3 not under ring scene is specific
Including following procedure:
(1) system receives the enabling signal and target rotation angle tracking signal that intelligent driving controller (entire car controller) issues;
(2) accurate tracking (lane holding) function of corner is realized by active corner tracking control algorithm.
Supplementary explanation:Refering to Fig. 6, electronic control unit ECU acquires intelligent driving controller (entire car controller) hair in real time
Enabling signal Auto_start and target rotation angle out tracks signal θd, system model judge algorithm first determine whether system enter turn
Angle/torque closed loop control mode.According to electric auxiliary steering system testing stand open loop frequency test result, specific direction disk corner
Input-front wheel angle output, steering wheel torque input-front wheel angle output open-loop amplitude phase-frequency characteristic, and reason is combined based on this
Think second order model design ring shaping controller and be eventually converted into motor bottom torque closed-loop control, to guarantee that system exists
So that corner/torque is preferably tracked desired corner/torque in certain responsive bandwidth, realizes active corner tracking (lane holding)
Function.
Hydraulic failure control function of the driver of the step 3 not under ring scene can specifically include following procedure:
(1) system acquisition steering wheel hand-power square and steering wheel angle signal;
(2) guarantee that vehicle is remained to according to driving in hydraulic booster subsystem failure by shift control algorithm of meeting an urgent need
Member is intended to complete the steering operation of necessary number.
Supplementary explanation:Refering to Fig. 7, electronic control unit ECU acquires driver's hand-power square T in real timehBelieve with steering wheel angle
Number θ, system model judge algorithm respectively by itself and preset hand torque threshold Th_thWith steering wheel angle threshold θ_thIt opposes
Than working as ThMore than given threshold Th_thAnd θ is less than given threshold θ_thWhen, cancel assist motor peak torque (being set to 7Nm) limit
System guarantees that vehicle remains to the steering operation that necessary number is completed according to driver intention under hydraulic booster subsystem failure.
Electrical steering lock function of the driver of the step 3 not under ring scene, specifically includes following procedure:
(1) system receives vehicle and steals signal;
(2) under the premise of turning to intention without prejudice to driver, realize that vehicle is turning to by electronic steering lock control algolithm
Anti-theft function in subsystem level.
Supplementary explanation:Refering to Fig. 8, electronic control unit ECU acquires vehicle theft signal Theft and steering wheel angle in real time
Signal θ, system model judge that algorithm judges that system enters electronic steering lock control model, are judged according to steering wheel angle signal θ
Driver, which turns to, to be intended to, and under the premise of turning to intention without prejudice to driver, is stepped up the reversed power-assisted of motor to be stepped up
Driver Steering Attention load, to realize that vehicle is turning to the anti-theft function in subsystem level.
Electric motor protecting function of the driver of the step 3 not under ring scene specifically includes following procedure:
(1) system real-time detection motor body temperature signal and system drive module temperature signal;
(2) necessary overheat protector is carried out to motor and system by electric motor protecting control logic.
Supplementary explanation:Refering to Fig. 9, electronic control unit ECU motor in real time body temperature signal Motor_temp and
System drive module temperature signal Power_temp, system model judge that algorithm judges that system enters motor overheat protector mode,
Overheat protector control algolithm is respectively by motor body temperature signal Motor_temp the same as preset motor body temperature threshold
1Motor_temp_th1 and threshold value 2Motor_temp_th2 are compared, then by system drive module temperature signal Power_
Temp makes comparisons with preset drive module temperature threshold 1Power_temp_1 and threshold value 2Power_temp_2;When
For Motor_temp beyond Motor_temp_th1 and in the case where being less than threshold value Motor_temp_th2, power drops in motor;It is greater than
In the case where Motor_temp_th2, motor stopping.When Power_temp beyond Motor_temp_th1 and is less than Motor_
In the case where temp_th2, power drops in motor;In the case where Motor_temp_th2, motor stopping.
It is emphasized that embodiment of the present invention be it is illustrative, without being restrictive, therefore packet of the present invention
Include and be not limited to embodiment described in specific embodiment, it is all by those skilled in the art according to the technique and scheme of the present invention
The other embodiments obtained, also belong to the scope of protection of the invention.