CN117507723A - Semi-active control method and system for hydraulic integrated type interconnected energy feedback suspension - Google Patents
Semi-active control method and system for hydraulic integrated type interconnected energy feedback suspension Download PDFInfo
- Publication number
- CN117507723A CN117507723A CN202311454764.3A CN202311454764A CN117507723A CN 117507723 A CN117507723 A CN 117507723A CN 202311454764 A CN202311454764 A CN 202311454764A CN 117507723 A CN117507723 A CN 117507723A
- Authority
- CN
- China
- Prior art keywords
- energy feedback
- semi
- vehicle
- speed
- suspension
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000000725 suspension Substances 0.000 title claims abstract description 125
- 238000000034 method Methods 0.000 title claims abstract description 59
- 230000001133 acceleration Effects 0.000 claims abstract description 68
- 238000013016 damping Methods 0.000 claims abstract description 28
- 230000001276 controlling effect Effects 0.000 claims description 11
- 230000001105 regulatory effect Effects 0.000 claims description 9
- 230000008859 change Effects 0.000 claims description 7
- 238000012545 processing Methods 0.000 claims description 7
- 238000004590 computer program Methods 0.000 claims description 5
- 230000004069 differentiation Effects 0.000 claims description 3
- 238000006073 displacement reaction Methods 0.000 claims description 3
- 230000005484 gravity Effects 0.000 claims description 3
- 230000005284 excitation Effects 0.000 description 17
- 238000011084 recovery Methods 0.000 description 15
- 230000008569 process Effects 0.000 description 7
- 230000001172 regenerating effect Effects 0.000 description 6
- 230000004044 response Effects 0.000 description 5
- 238000011160 research Methods 0.000 description 3
- 238000011217 control strategy Methods 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 239000006096 absorbing agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000004422 calculation algorithm Methods 0.000 description 1
- 238000004364 calculation method Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 230000036461 convulsion Effects 0.000 description 1
- 239000008358 core component Substances 0.000 description 1
- 230000001627 detrimental effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000002708 enhancing effect Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000005096 rolling process Methods 0.000 description 1
- 230000035939 shock Effects 0.000 description 1
- 238000004088 simulation Methods 0.000 description 1
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
- B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
- B60G17/018—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the use of a specific signal treatment or control method
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
- B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
- B60G17/019—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the type of sensor or the arrangement thereof
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
- B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
- B60G17/019—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the type of sensor or the arrangement thereof
- B60G17/01908—Acceleration or inclination sensors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G17/00—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load
- B60G17/015—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements
- B60G17/019—Resilient suspensions having means for adjusting the spring or vibration-damper characteristics, for regulating the distance between a supporting surface and a sprung part of vehicle or for locking suspension during use to meet varying vehicular or surface conditions, e.g. due to speed or load the regulating means comprising electric or electronic elements characterised by the type of sensor or the arrangement thereof
- B60G17/01933—Velocity, e.g. relative velocity-displacement sensors
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
- B60G2400/10—Acceleration; Deceleration
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
- B60G2400/10—Acceleration; Deceleration
- B60G2400/102—Acceleration; Deceleration vertical
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
- B60G2400/20—Speed
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2400/00—Indexing codes relating to detected, measured or calculated conditions or factors
- B60G2400/40—Steering conditions
- B60G2400/41—Steering angle
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60G—VEHICLE SUSPENSION ARRANGEMENTS
- B60G2600/00—Indexing codes relating to particular elements, systems or processes used on suspension systems or suspension control systems
- B60G2600/18—Automatic control means
- B60G2600/184—Semi-Active control means
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Vehicle Body Suspensions (AREA)
Abstract
The invention provides a semi-active control method of a hydraulic integrated type interconnected energy feedback suspension, which comprises the following steps: constructing an energy feedback circuit; acquiring vehicle running information, and acquiring the vehicle body attitude speed of the vehicle according to the vehicle running information; when the vehicle body posture speed is greater than a set vehicle body posture speed threshold value and the state duration is greater than a set time threshold value, adopting a PID control method, and adjusting the size of a variable resistor according to the voltage drop of the energy feedback circuit to control the current size of the energy feedback circuit, thereby controlling the damping of the semi-active interconnected energy feedback suspension, and adjusting the three-way acceleration of the vehicle to be 0 according to the damping; when the vehicle body posture speed is smaller than the set vehicle body posture speed threshold value and the state duration is larger than the set time threshold value, the control parameters of the PID controller are dynamically adjusted by adopting a fuzzy PID control method, and then the square sum of the three-way acceleration of the vehicle is adjusted to be smaller than the set acceleration square sum threshold value by adopting the PID control method, so that the vehicle runs stably.
Description
Technical Field
The invention relates to the technical field of vehicle suspension control, in particular to a semi-active control method and system for a hydraulic integrated type interconnected energy feedback suspension.
Background
In the process of automobile technical development, a high-performance suspension control method is always the focus of research, and is used as one of indexes for measuring automobile quality, and the high-performance suspension control method is directly related to comfort, steering stability and safety of a vehicle during running. Compared with the traditional interconnection suspension and energy feedback suspension, the hydraulic integrated interconnection energy feedback suspension is a novel suspension combining the advantages of the interconnection suspension and the energy feedback suspension, and has the characteristics of excellent anti-roll and anti-pitch capability of the interconnection suspension and energy recovery of the energy feedback suspension. The hydraulic integrated type interconnected energy feedback suspension can better meet the requirements of the suspension on the whole performance, cost, energy recovery and the like, so that the hydraulic integrated type interconnected energy feedback suspension has very broad development prospect. The hydraulic integrated type interconnected energy feedback suspension can also adjust the damping of the suspension and the energy feedback power of the energy feedback unit by adjusting the size of an external resistor in the energy feedback circuit, which is the realization foundation of the semi-active control system.
At present, most of researches on the hydraulic integrated type interconnected energy feedback suspension are focused on the aspects of time domain and frequency domain analysis, energy recovery characteristics and the like of the interconnected energy feedback suspension, and few researches on the semi-active control strategy of the hydraulic integrated type interconnected energy feedback suspension are carried out. The method is particularly suitable for control under complex road surface change, the traditional control method is not suitable for any more, the control system cannot establish a relation with external excitation, the rigidity and damping of the suspension can not be adjusted according to the road surface condition of the automobile, the requirement that the parameters of the controller are in an optimal state can not be met, the traditional control mode is low in adjustment precision, the real-time signal processing is simple, and the interconnected energy feedback suspension can not be well adjusted when the external excitation change is large.
Disclosure of Invention
The invention provides a semi-active control method and a semi-active control system for a hydraulic integrated interconnected energy feedback suspension, which are used for judging a driving state according to relevant dynamic parameters of a vehicle, controlling variable resistors in an energy feedback circuit by adopting different control methods according to requirements of different states on the dynamic performance of the vehicle, improving the operation stability and safety of the vehicle, greatly improving the driving comfort of a driver and enhancing the capability of the hydraulic integrated interconnected energy feedback suspension system for adapting to a complex road surface.
In order to achieve the above purpose, the invention provides a semi-active control method of a hydraulic integrated interconnected energy feedback suspension, which comprises the following steps:
step S1: constructing an energy feedback circuit, wherein the energy feedback circuit comprises a variable resistor and a PID controller;
step S2: acquiring vehicle running information, wherein the vehicle running information comprises steering wheel rotation angle, three-way speed and three-way acceleration;
step S3: acquiring the vehicle body attitude speed of the vehicle according to the vehicle running information;
step S4: executing step S5 when the vehicle body posture speed is greater than the set vehicle body posture speed threshold and the state duration is greater than the set time threshold, and executing step S6 when the vehicle body posture speed is less than the set vehicle body posture speed threshold and the state duration is greater than the set time threshold;
step S5: the PID control method is adopted, the size of the variable resistor is adjusted according to the voltage drop of the energy feedback circuit, so that the current size of the energy feedback circuit is controlled, the damping of the semi-active interconnection energy feedback suspension is controlled, and the three-way acceleration of the vehicle is adjusted to be 0 according to the damping;
step S6: dynamically adjusting control parameters of the PID controller by adopting a fuzzy PID control method, and adjusting the size of the variable resistor according to the voltage drop of the energy feedback circuit by adopting the PID control method so as to control the current size of the energy feedback circuit, thereby controlling the damping of the semi-active interconnection energy feedback suspension, and adjusting that the square sum of three-way acceleration of the vehicle is smaller than a set square sum threshold value of acceleration;
step S7: and adjusting the vehicle body posture speed of the vehicle to set a vehicle body posture speed threshold value so as to enable the vehicle to stably run.
Preferably, the three-way speed in step S1 includes a vertical speed, a roll speed, and a pitch speed, and the three-way acceleration includes a vertical acceleration, a roll acceleration, and a pitch acceleration.
Preferably, the voltage drop of the energy feedback circuit in step S5 is:
wherein n is g Is the speed ratio of the gearbox between the hydraulic motor and the generator, J g For moment of inertia of the rotating part, eta v And eta m Volumetric and mechanical efficiency, q, respectively, of the hydraulic motor m For displacement, k of hydraulic motor e And k t Respectively the voltage constant and the torque constant of the generator, R i And R is e External resistances of internal resistance and energy feedback circuit of generator, Q m Is the inlet flow of the hydraulic motor.
Preferably, the PID control method in step S5 includes the steps of:
step S51: inputting the square sum of the three-way speed into a PID controller;
step S52: the PID controller compares the square sum of the three-way speed with a set speed square sum threshold value to obtain a deviation value of the square sum and the speed;
step S53: performing function operation on the deviation value, and taking an operation result as the output of the PID controller;
step S54: the energy feedback circuit adjusts the magnitude of an external resistor in the energy feedback circuit according to the output of the PID controller, so as to control the magnitude of current and control the damping of the semi-active interconnection energy feedback suspension;
step S55: and adjusting the acceleration of the vehicle according to the damping.
Preferably, the fuzzy PID control method in step S6 includes the steps of:
step S61: comparing the square sum of the acceleration with a set acceleration square sum threshold value to obtain a deviation value e of the square sum of the acceleration and the set acceleration;
step S62: performing fuzzy processing on the square sum of the accelerations and the differentiation of the square sum of the accelerations to obtain a fuzzy set;
step S63: according to the fuzzy set, designing a fuzzy control rule;
step S64: taking the deviation value e and the change rate ec of the deviation value along with time as the input of a fuzzy controller, and adjusting the control parameters of the PID controller by utilizing the fuzzy control rule;
step S65: and (3) performing definition processing on the control parameters of the regulated PID controller by adopting a Mamdani fuzzy reasoning method and a gravity center method, and taking the control parameters as input of the PID controller.
The invention also provides a semi-active control system of the hydraulic integrated interconnection energy feedback suspension, which comprises a hydraulic interconnection module, an information acquisition module, a semi-active control module and an energy feedback circuit module;
the hydraulic interconnection module is connected with the hydraulic integrated interconnection energy feedback suspension and the semi-active control module so as to realize semi-active control of the suspension;
the information acquisition module is used for acquiring steering wheel rotation angle, speed and acceleration of the whole vehicle and inputting the acquired information into the semi-active control module;
the semi-active control module receives the information input by the information acquisition module, judges the running state of the whole vehicle, and outputs a switching control instruction to the energy feedback circuit module according to the running state;
the energy feedback circuit module is used for controlling an energy feedback circuit of the hydraulic integrated type interconnected energy feedback suspension.
Preferably, the hydraulic interconnection module comprises a hydraulic cylinder, a rectifying valve block formed by four one-way valves, a high-pressure energy accumulator, a low-pressure energy accumulator, a hydraulic motor, a generator, a semi-active control module, an energy feedback circuit and a plurality of hydraulic pipelines.
Preferably, the information acquisition module comprises a vehicle speed sensor, a steering wheel steering angle sensor, an acceleration sensor, a speed sensor and a brake cylinder pressure sensor.
Preferably, the energy feedback circuit module comprises a driving circuit and a variable resistor.
The invention also provides a computer readable storage medium storing a computer program which when executed by a processor realizes the semi-active control method of the hydraulic integrated interconnection energy feedback suspension.
The beneficial effects of the invention at least comprise:
1. the hydraulic integrated type interconnection energy feedback suspension is adopted, the characteristics of excellent anti-roll and anti-pitch capability of the interconnection suspension and energy recovery of the energy feedback suspension are provided, and the current of the energy feedback circuit is controlled by adjusting the external resistance in the energy feedback circuit, so that the damping of the hydraulic integrated type interconnection energy feedback suspension and the energy feedback power of the energy feedback unit can be controlled;
2. according to the invention, the running state of the vehicle is judged based on the sensor running signal, and different control modes are set under the high-frequency excitation state and the low-frequency excitation state, so that the control problem under the complex road surface of the running vehicle is solved, the damping is controllable in real time, and meanwhile, the recovery of vibration energy is realized;
3. the control strategy established by the invention is simple and effective, can accurately, rapidly and stably identify according to the dynamic parameters of the vehicle, and improves the driving performance.
Drawings
FIG. 1 is a flow chart of a method according to an embodiment of the present invention;
FIG. 2 is an example of low frequency vertical excitation according to an embodiment of the present invention;
FIG. 3 is an example of a low frequency steering excitation according to an embodiment of the present invention;
FIG. 4 is an example of a low frequency brake actuation of an embodiment of the present invention;
FIG. 5 is an example of low frequency coupled excitation according to an embodiment of the present invention;
FIG. 6 is an example of high frequency excitation according to an embodiment of the present invention;
fig. 7 is a schematic diagram of a system structure according to an embodiment of the invention.
Detailed Description
The following description of the embodiments of the present invention will be made clearly and completely with reference to the accompanying drawings, in which it is evident that the embodiments described are only some embodiments of the present invention, but not all embodiments. All other embodiments, which can be made by a person skilled in the art without any inventive effort, are intended to be within the scope of the present invention, based on the embodiments of the present invention.
As shown in fig. 1, the embodiment of the invention provides a semi-active control method of a hydraulic integrated interconnection energy feedback suspension, which comprises the following steps:
step S1: and constructing an energy feedback circuit comprising a variable resistor and a PID controller.
Specifically, the voltage drop of the energy feedback circuit is as follows:
wherein n is g Is the speed ratio of the gearbox between the hydraulic motor and the generator, J g For moment of inertia of the rotating part, eta v And eta m Volumetric and mechanical efficiency, q, respectively, of the hydraulic motor m For displacement, k of hydraulic motor e And k t Respectively the voltage constant and the torque constant of the generator, R i And R is e External resistances of internal resistance and energy feedback circuit of generator, Q m Is the inlet flow of the hydraulic motor.
Wherein the adjustable portion is:
the adjustable part is related to the voltage drop delta P generated by the energy feedback unit part consisting of the generator and the hydraulic motor, so that the state of the hydraulic integrated type interconnected energy feedback suspension is controllable under the high-low frequency excitation conversion, and the external resistance R in the energy feedback circuit can be changed e To realize the method. And an external resistance R e Is inversely proportional to the voltage drop generated by the energy feedback unit part, R e The smaller the value, the greater the damping of the system. Therefore, the energy feedback circuit adopts a variable resistance resistor, and the external resistance of the energy feedback circuit is controlled according to the change of the high frequency and the low frequency of the running vehicle to control the current of the energy feedback circuit, thereby realizing the control of the damping of the semi-active interconnection energy feedback suspension.
Step S2: and acquiring vehicle running information, including steering wheel rotation angle, three-way speed and three-way acceleration.
Step S3: the body posture speed of the vehicle is obtained from the vehicle running information.
Step S4: when the vehicle body posture speed is greater than the set vehicle body posture speed threshold and the state duration is greater than the set time threshold, step S5 is executed, and when the vehicle body posture speed is less than the set vehicle body posture speed threshold and the state duration is greater than the set time threshold, step S6 is executed.
Specifically, the sensor sends the received signal to the electronic control unit ECU, compares the received speed of the vehicle body gesture with a preset threshold interval, and judges that the vehicle is excited by low frequency at the moment if the speed signal exceeds the preset threshold interval and the state time exceeds the preset reference threshold time; if the magnitude of the speed signal is lower than the set threshold interval and the state time exceeds the preset reference threshold time, the vehicle is judged to be excited by high frequency at the moment.
Step S5: and a PID control method is adopted, the size of the variable resistor is regulated according to the voltage drop of the energy feedback circuit, so that the current size of the energy feedback circuit is controlled, the damping of the semi-active interconnection energy feedback suspension is controlled, and the three-way acceleration of the vehicle is regulated to be 0 according to the damping.
Specifically, sudden conditions are encountered when the vehicle is running, such as sudden road surface protrusions or pits, sudden braking of the vehicle, sharp turns and other extreme driving conditions. The vehicle chassis has larger posture change and is easy to roll, pitch and vertically jump with larger amplitude. Which is detrimental to the steering stability of the vehicle. The control method under low frequency excitation aims to solve these problems. Therefore, the control target is the magnitude of three accelerations of the vehicle with the hydraulic integrated type interconnected energy feedback suspension, and the output is suspension power. The external resistance of the energy feedback circuit is used as a control variable, the current of the energy feedback circuit is controlled, the control target is zero of the three-way speed of the vehicle, and the damping control algorithm of the semi-active interconnection energy feedback suspension is PID control.
The control mode of the low-frequency excited hydraulic integrated type interconnected energy-feedback suspension semi-active control system is traditional PID control, and the input of the ECU is the square sum of the vertical velocity, the square sum of the roll velocity and the square sum of the pitch velocity. The square sum of the three speeds is used as input to enable the ECU to input zero, and the three gesture speeds are all zero, so that the running stability of the whole vehicle is ensured. Because the damping of the hydraulic integrated type interconnected energy feedback suspension and the external resistance of the energy feedback circuit are in a negative correlation, when the ECU input is not zero, the acceleration of the automobile posture is not zero, and the chassis of the automobile is in an unstable state because the acceleration is not zero. To counteract such jerk conditions, it is desirable to reduce chassis speed to zero, where the hydraulic integrated interconnected feed suspension provides greater damping, where the corresponding is a lower external resistance in the feed circuit, where the feed circuit current is higher and the energy recovery is better.
Specifically, the control method under low frequency excitation includes the steps of:
step S51: the sum of squares of the three-way speeds including the vertical speed, roll speed and pitch speed of the vehicle body is input to the PID controller.
Step S52: and the PID controller compares the square sum of the three-way speed with a set speed square sum threshold value to obtain a deviation value of the two.
Step S53: and after receiving the deviation value, the PID controller calculates according to the functional relation of the proportion, the integral and the derivative, and takes the calculation result as the output of the PID controller.
Step S54: the energy feedback circuit adjusts the magnitude of an external resistor in the energy feedback circuit according to the output of the PID controller, so as to control the magnitude of current and control the damping of the semi-active interconnection energy feedback suspension.
Step S55: and adjusting the acceleration of the vehicle according to the damping.
The low frequency excitation of a vehicle mainly includes three aspects: the vehicle runs with larger bumps or drops, and the excitation of the wheels can be approximately a step input, which is a running scene with larger influence on the steering stability and safety of the vehicle, so the control parameter K of the PID controller applied to the energy feedback circuit p 、K i And K d Can be determined from the simulation results.
A first embodiment shows a situation where a vehicle equipped with an interconnected regenerative suspension semi-active control system is subjected to a step input, as shown in fig. 2 (a), to simulate a pit or bump that the vehicle suddenly encounters during travel. The vertical speed, the roll speed and the pitch speed of the vehicle body are square and then summed and then used as the input of the ECU and are input into a semi-active interconnection energy feedback suspension PID controller. The PID controller outputs a resistance value, the variable resistor in the energy feedback circuit receives an output signal of the PID controller, the size of the external resistor in the energy feedback circuit is regulated, and the current of the energy feedback circuit is controlled, so that the purpose of controlling the semi-active interconnection energy feedback suspension while energy recovery can be realized. The response of the vertical velocity, roll angle velocity and pitch angle velocity of the conventional suspension, the passive interconnected regenerative suspension and the semi-active interconnected regenerative suspension at the same step input are shown in fig. 2 (b), (c) and (d), respectively.
The second embodiment shows a situation of a sharp turn in the running process of a vehicle with an interconnected energy feedback suspension semi-active control system, the vehicle receives a steering signal with larger amplitude, and the steering signal is input as shown in (a) of fig. 3. The vertical speed, roll speed and pitch speed of the vehicle body are squared and summed and then input to the PID controller as inputs to the controller. The PID controller outputs a resistance value, the variable resistor in the energy feedback circuit receives an output signal of the PID controller, the size of the external resistor in the energy feedback circuit is regulated, and the current of the energy feedback circuit is controlled, so that the purpose of controlling the semi-active interconnection energy feedback suspension while energy recovery can be realized. Fig. 3 (b), (c) and (d) show the response of the conventional suspension, the passive suspension and the semi-active interconnected energy-feedback suspension to the vertical velocity, the roll velocity and the pitch velocity, respectively, at the same steering angle input.
In the third embodiment, the situation of sudden braking during the running process of the vehicle with the interconnected energy feedback suspension semi-active control system is shown, the braking system of the vehicle receives a braking signal, the braking pressure is shown as (a) in fig. 4, the vehicle brakes, and the whole vehicle is pitching. The vertical speed, the roll speed and the pitch speed of the vehicle body are square and then summed and then used as the input of a controller and are input into a PID controller of the semi-active interconnection energy feedback suspension. The PID controller outputs a resistance value, the variable resistor in the energy feedback circuit receives an output signal of the PID controller, the size of the external resistor in the energy feedback circuit is regulated, and the current of the energy feedback circuit is controlled, so that the purpose of controlling the semi-active interconnection energy feedback suspension while energy recovery can be realized. The response of the conventional, passive and semi-active interconnected feed suspensions to the vertical, roll and pitch rates at the same brake pressure input is shown in fig. 4 (b), (c) and (d), respectively.
The fourth embodiment shows a low-frequency coupling scene in the running process of a vehicle with an interconnection energy feedback suspension semi-active control system, and represents three scenes of simultaneously meeting road surface protrusions, steering of a steering system and braking of a braking system in the running process of the vehicle. At this time, the speeds of the vehicle body in three directions reach a relatively large value. The vertical speed, the roll speed and the pitch speed of the vehicle body are square and then summed and then used as the input of the controller and are input into the semi-active interconnection energy feedback suspension PID controller. The PID controller outputs a resistance value, a variable resistor in the energy feedback circuit receives an output signal of the PID controller, the size of an external resistor in the energy feedback circuit is regulated, and the current of the energy feedback circuit is controlled, so that the semi-active interconnection energy feedback suspension is controlled while energy recovery is realized. Fig. 5 (a), (b) and (c) show the response of the conventional suspension, the passive suspension and the semi-active interconnected energy-feedback suspension at the same coupling input vertical speed, roll angle speed and pitch angle speed, respectively.
Step S6: the control parameters of the PID controller are dynamically adjusted by adopting a fuzzy PID control method, and then the size of the variable resistor is adjusted according to the voltage drop of the energy feedback circuit by adopting the PID control method so as to control the current size of the energy feedback circuit, thereby controlling the damping of the semi-active interconnection energy feedback suspension, and adjusting the square sum of the three-way acceleration of the vehicle to be smaller than the set square sum threshold of the acceleration.
Specifically, during normal running of the vehicle, the driver may want the smaller the acceleration stimulus of the vehicle, the better the riding comfort of the vehicle. Therefore, in the case of high-frequency traveling, the control target is to make the riding comfort higher and the better, and the evaluation index is the acceleration of the vehicle. The smaller this value, the better the ride comfort of the vehicle. Therefore, the control target is the square sum of the vertical acceleration, the rolling acceleration and the pitching acceleration of the vehicle with the hydraulic integrated interconnected energy feedback suspension, the aim of comprehensive control can be achieved, the adopted control variable is the external resistance of the energy feedback circuit, and the current of the energy feedback circuit is controlled, so that the hydraulic integrated interconnected energy feedback suspension is controlled.
The semi-active interconnection energy feedback suspension is different from a low-frequency controller in high-frequency excitation, because the target signal to be detected in high-frequency excitation is an acceleration signal, the semi-active interconnection energy feedback suspension has randomness, and can not cope with all working conditions by adopting a simple traditional PID controller like the low-frequency controller. Therefore, a fuzzy PID controller is adopted, the fuzzy controller is used for controlling the control parameters of the PID controller, the magnitude of an external resistor in the energy feedback circuit is regulated, the magnitude of current of the energy feedback circuit is controlled, and the semi-active interconnection energy feedback suspension is controlled while the energy recovery is finally realized so as to adapt to various driving scenes.
Specifically, the control method under high-frequency excitation includes the steps of:
step S61: and comparing the square sum of the accelerations with a set square sum threshold value of the accelerations to obtain a deviation value e of the square sum of the accelerations and the set square sum threshold value of the accelerations.
Step S62: and carrying out fuzzy processing on the square sum of the accelerations and the differentiation of the square sum of the accelerations to obtain a fuzzy set.
Specifically, since the sum-of-squares signals of accelerations are positive numbers, they are described in four fuzzy sets, i.e., { Z } 0 ,P S ,P M ,P B Differential of acceleration signal is described in seven ambiguities, i.e., { N S ,N M ,N B ,Z 0 ,P S ,P M ,P B N, where S Is small in negative and N M Is negative, medium and N B Is of negative big, Z 0 Is 0, P S Is just small, P M Is the center, P B Is positive.
Step S63: and designing a fuzzy control rule according to the fuzzy set.
Specifically, the control parameter K of the PID controller p 、K i 、K d The fuzzy inference rules of (a) are shown in tables 1 to 3, respectively.
Table 1K p Is a fuzzy rule table of (a)
Table 2K i Is a fuzzy rule table of (a)
Table 3K d Is a fuzzy rule table of (a)
Step S64: and taking the deviation value e and the change rate ec of the deviation value along with time as the input of the fuzzy controller, and adjusting the control parameters of the PID controller by utilizing a fuzzy control rule.
Step S65: and the control parameters of the adjusted PID controller are subjected to definition processing by adopting a Mamdani fuzzy reasoning method and a gravity center method, and serve as the input of the PID controller, the membership function selects a triangular membership function, and the membership function maps the input acceleration signals to a membership space, so that the input parameters are provided for the controller, and the precision and stability of the fuzzy controller are improved.
Fig. 6 (a), (b) and (c) show the response of the conventional suspension, the passive suspension and the semi-active interconnected energy-feedback suspension to vertical acceleration, roll acceleration and pitch acceleration, respectively, under the same random road surface input.
Step S7: and adjusting the vehicle body posture speed of the vehicle to set a vehicle body posture speed threshold value so as to enable the vehicle to stably run.
As can be seen from fig. 2 to 6, the vehicle equipped with the semi-active interconnected regenerative suspension control system has excellent anti-roll and anti-pitch capabilities of the interconnected suspension and the characteristics of regenerative suspension energy recovery compared with the conventional suspension and the passive interconnected regenerative suspension. The energy recovery is realized, and meanwhile, the variable resistor in the semi-active interconnection energy feedback suspension energy feedback circuit is controlled, so that the current of the energy feedback circuit is controlled, the gesture speed of a chassis system under a low-frequency limit driving is obviously reduced, the time for the chassis speed to reach zero is greatly shortened, the chassis can be quickly leveled and stabilized under the condition of being excited by the outside, the operation stability is improved, and the accident occurrence probability is reduced. Meanwhile, under high-frequency excitation, the vertical acceleration root mean square of a vehicle provided with the semi-active interconnected energy feedback suspension control system is reduced by 56.43% compared with a traditional suspension, and is reduced by 32.03% compared with a passive interconnected energy feedback suspension. The roll acceleration of the semi-active control suspension is reduced by 81.7% compared with that of a traditional suspension and is reduced by 5.93% compared with that of a passive interconnection energy feedback suspension. The pitching acceleration of the vehicle provided with the semi-active interconnection energy feedback suspension control system is reduced by 52.21 percent compared with that of a traditional suspension and is reduced by 23.64 percent compared with that of a passive interconnection energy feedback suspension.
The invention also provides a computer readable storage medium which stores a computer program, and the computer program realizes the semi-active control method of the hydraulic integrated type interconnected energy feedback suspension when being executed by a processor.
As shown in FIG. 7, the invention further provides a semi-active control system of the hydraulic integrated interconnection energy feedback suspension, which comprises a hydraulic interconnection module, an information acquisition module, a semi-active control module and an energy feedback circuit module.
The hydraulic interconnection module is connected with the hydraulic integrated interconnection energy feedback suspension and the semi-active control module so as to realize semi-active control of the suspension, and the hydraulic integrated interconnection energy feedback suspension comprises a hydraulic cylinder a, a hydraulic cylinder b, a hydraulic cylinder c, a hydraulic cylinder d, a rectifying valve block a, a rectifying valve block b, a rectifying valve block c, a rectifying valve block d, a high-pressure energy accumulator, a low-pressure energy accumulator, a hydraulic motor, a generator, a semi-active control module and a plurality of hydraulic pipelines.
Four hydraulic cylinders in the hydraulic interconnection module replace the shock absorber in the traditional suspension to restrain impact force in the vehicle vibration process. The damping of the hydraulic integrated interconnected energy feedback suspension is generated by a pipeline, a rectifying valve block, a hydraulic motor and a generator, wherein electromagnetic torque generated in the rotation process of the motor part is directly proportional to the current in the energy feedback loop, and meanwhile, the current generated by the motor can be collected for energy recovery. Therefore, the damping of the suspension can be adjusted by adjusting the current in the energy feedback circuit, so that the hydraulic integrated interconnected energy feedback suspension has excellent performance when running on high-frequency and low-frequency roads.
The information acquisition module comprises a vehicle speed sensor, a steering wheel steering angle sensor, an acceleration sensor, a speed sensor and a brake cylinder pressure sensor, and is used for acquiring steering wheel angles, vehicle speeds and accelerations of the whole vehicle and inputting the acquired information into the semi-active control module.
The semi-active control module receives the information input by the information acquisition module, judges the running state of the whole vehicle, and the hydraulic integrated type interconnected energy feedback suspension semi-active control system outputs a switching control instruction to the energy feedback circuit module according to the running state;
the energy feedback circuit module comprises a driving circuit and a variable resistor, and is used for controlling an energy feedback circuit of the hydraulic integrated type interconnected energy feedback suspension, and the energy feedback circuit module is also a core component for realizing energy recovery.
The foregoing embodiments may be combined in any way, and all possible combinations of the features of the foregoing embodiments are not described for brevity, but only the preferred embodiments of the invention are described in detail, which should not be construed as limiting the scope of the invention. The scope of the present specification should be considered as long as there is no contradiction between the combinations of these technical features.
It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the invention, which are all within the scope of the invention. Accordingly, the scope of protection of the present invention is to be determined by the appended claims.
Claims (10)
1. The semi-active control method of the hydraulic integrated interconnection energy feedback suspension is characterized by comprising the following steps of:
step S1: constructing an energy feedback circuit, wherein the energy feedback circuit comprises a variable resistor and a PID controller;
step S2: acquiring vehicle running information, wherein the vehicle running information comprises steering wheel rotation angle, three-way speed and three-way acceleration;
step S3: acquiring the vehicle body attitude speed of the vehicle according to the vehicle running information;
step S4: executing step S5 when the vehicle body posture speed is greater than the set vehicle body posture speed threshold and the state duration is greater than the set time threshold, and executing step S6 when the vehicle body posture speed is less than the set vehicle body posture speed threshold and the state duration is greater than the set time threshold;
step S5: the PID control method is adopted, the size of the variable resistor is adjusted according to the voltage drop of the energy feedback circuit, so that the current size of the energy feedback circuit is controlled, the damping of the semi-active interconnection energy feedback suspension is controlled, and the three-way acceleration of the vehicle is adjusted to be 0 according to the damping;
step S6: dynamically adjusting control parameters of the PID controller by adopting a fuzzy PID control method, and adjusting the size of the variable resistor according to the voltage drop of the energy feedback circuit by adopting the PID control method so as to control the current size of the energy feedback circuit, thereby controlling the damping of the semi-active interconnection energy feedback suspension, and adjusting that the square sum of three-way acceleration of the vehicle is smaller than a set square sum threshold value of acceleration;
step S7: and adjusting the vehicle body posture speed of the vehicle to set a vehicle body posture speed threshold value so as to enable the vehicle to stably run.
2. The semi-active control method of the hydraulic integrated interconnection energy feedback suspension according to claim 1, wherein the method comprises the following steps: the three-way speeds in step S1 include a vertical speed, a roll speed, and a pitch speed, and the three-way accelerations include a vertical acceleration, a roll acceleration, and a pitch acceleration.
3. The semi-active control method of the hydraulic integrated interconnection energy feedback suspension according to claim 1, wherein the method comprises the following steps: the voltage drop of the energy feedback circuit in step S5 is as follows:
wherein n is g Is the speed ratio of the gearbox between the hydraulic motor and the generator, J g For moment of inertia of the rotating part, eta v And eta m Volumetric and mechanical efficiency, q, respectively, of the hydraulic motor m For displacement, k of hydraulic motor e And k t Respectively the voltage constant and the torque constant of the generator, R i And R is e External resistances of internal resistance and energy feedback circuit of generator, Q m Is the inlet flow of the hydraulic motor.
4. The semi-active control method of the hydraulic integrated interconnection energy feedback suspension according to claim 1, wherein the method comprises the following steps: the PID control method in the step S5 comprises the following steps:
step S51: inputting the square sum of the three-way speed into a PID controller;
step S52: the PID controller compares the square sum of the three-way speed with a set speed square sum threshold value to obtain a deviation value of the square sum and the speed;
step S53: performing function operation on the deviation value, and taking an operation result as the output of the PID controller;
step S54: the energy feedback circuit adjusts the magnitude of an external resistor in the energy feedback circuit according to the output of the PID controller, so as to control the magnitude of current and control the damping of the semi-active interconnection energy feedback suspension;
step S55: and adjusting the acceleration of the vehicle according to the damping.
5. The semi-active control method of the hydraulic integrated interconnection energy feedback suspension according to claim 1, wherein the method comprises the following steps: the fuzzy PID control method in the step S6 comprises the following steps:
step S61: comparing the square sum of the acceleration with a set acceleration square sum threshold value to obtain a deviation value e of the square sum of the acceleration and the set acceleration;
step S62: performing fuzzy processing on the square sum of the accelerations and the differentiation of the square sum of the accelerations to obtain a fuzzy set;
step S63: according to the fuzzy set, designing a fuzzy control rule;
step S64: taking the deviation value e and the change rate ec of the deviation value along with time as the input of a fuzzy controller, and adjusting the control parameters of the PID controller by utilizing the fuzzy control rule;
step S65: and (3) performing definition processing on the control parameters of the regulated PID controller by adopting a Mamdani fuzzy reasoning method and a gravity center method, and taking the control parameters as input of the PID controller.
6. A semi-active control system of a hydraulic integrated interconnection energy feedback suspension, which is suitable for a semi-active control method of a hydraulic integrated interconnection energy feedback suspension according to any one of claims 1-5, and is characterized in that: the control system comprises a hydraulic interconnection module, an information acquisition module, a semi-active control module and an energy feedback circuit module;
the hydraulic interconnection module is connected with the hydraulic integrated interconnection energy feedback suspension and the semi-active control module so as to realize semi-active control of the suspension;
the information acquisition module is used for acquiring steering wheel rotation angle, speed and acceleration of the whole vehicle and inputting the acquired information into the semi-active control module;
the semi-active control module receives the information input by the information acquisition module, judges the running state of the whole vehicle, and outputs a switching control instruction to the energy feedback circuit module according to the running state;
the energy feedback circuit module is used for controlling an energy feedback circuit of the hydraulic integrated type interconnected energy feedback suspension.
7. The semi-active control system of the hydraulic integrated interconnection energy feedback suspension according to claim 6, wherein: the hydraulic interconnection module comprises a hydraulic cylinder, a rectifying valve block formed by four one-way valves, a high-pressure energy accumulator, a low-pressure energy accumulator, a hydraulic motor, a generator, a semi-active control module, an energy feedback circuit and a plurality of hydraulic pipelines.
8. The semi-active control system of the hydraulic integrated interconnection energy feedback suspension according to claim 6, wherein: the information acquisition module comprises a vehicle speed sensor, a steering wheel steering angle sensor, an acceleration sensor, a speed sensor and a brake cylinder pressure sensor.
9. The semi-active control system of the hydraulic integrated interconnection energy feedback suspension according to claim 6, wherein: the energy feedback circuit module comprises a driving circuit and a variable resistor.
10. A computer readable storage medium storing a computer program, wherein the computer program when executed by a processor implements a semi-active control method of a hydraulic integrated interconnection feed suspension according to any one of claims 1 to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311454764.3A CN117507723A (en) | 2023-11-03 | 2023-11-03 | Semi-active control method and system for hydraulic integrated type interconnected energy feedback suspension |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311454764.3A CN117507723A (en) | 2023-11-03 | 2023-11-03 | Semi-active control method and system for hydraulic integrated type interconnected energy feedback suspension |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN117507723A true CN117507723A (en) | 2024-02-06 |
Family
ID=89752372
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311454764.3A Pending CN117507723A (en) | 2023-11-03 | 2023-11-03 | Semi-active control method and system for hydraulic integrated type interconnected energy feedback suspension |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN117507723A (en) |
-
2023
- 2023-11-03 CN CN202311454764.3A patent/CN117507723A/en active Pending
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN103707734B (en) | Suspension control apparatus | |
| CN102729760B (en) | Real-time optimal damping control algorithm of automobile semi-active suspension system | |
| CN107825930B (en) | A kind of intelligent fuzzy mixing canopy semi-active control method for vehicle suspension system | |
| Yoshimura et al. | Steering and suspension system of a full car model using fuzzy reasoning based on single input rule modules | |
| CN101916113B (en) | Automotive body gesture decoupling control method based on active suspension evaluation indicator | |
| CN100484788C (en) | Apery intelligent control method for harmonizing auto magnetorheological half-initiative suspension according to posture | |
| US20020185827A1 (en) | Method and apparatus for controlling a vehicle suspension system based on sky hook approach | |
| CN108891220B (en) | Ceiling control improvement method for semi-active suspension system of vehicle | |
| WO2013111734A1 (en) | Vehicle control system and vehicle control method | |
| WO2013111736A1 (en) | Vehicle control system and vehicle control method | |
| CN109292019B (en) | All-terrain vehicle active body attitude control method based on coaxial wheel leg structure | |
| CN112339517A (en) | Semi-active suspension control method and system | |
| CN102189909A (en) | Filtering control strategy for skyhook damping frequencies of semi-active suspension of vehicle | |
| CN105539052B (en) | A kind of controllable suspension sliding formwork tracking controller using vehicle plateau as reference | |
| CN112848832B (en) | Vehicle integrated control method and vehicle integrated control system | |
| CN110001339B (en) | Semi-active control method for suspension of tire burst vehicle | |
| CN107054353A (en) | The driving-force control apparatus of vehicle | |
| Tianjun et al. | Model reference adaptive control of semi-active suspension model based on AdaBoost algorithm for rollover prediction | |
| WO2023174327A1 (en) | Cooperative control module, adaptive cruise control system as well as control method thereof, and vehicle | |
| CN114590090A (en) | Direct-drive semi-active suspension control system construction method based on self-adaptive LQR (Low-speed response) wheel hub | |
| CN110341414B (en) | Suspension self-adaptive optimal control system and method under continuous linear ceiling control | |
| Zhao et al. | PID control of vehicle active suspension based on particle Swarm optimization | |
| CN110901326A (en) | Control method of active suspension system with state constraint and dead zone input | |
| CN117507723A (en) | Semi-active control method and system for hydraulic integrated type interconnected energy feedback suspension | |
| Cheng et al. | Fuzzy controller design for vehicle active suspensions based on genetic algorithm |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |