CN110978932B - Integrated composite suspension actuator and control method thereof - Google Patents

Abstract

The invention belongs to the technical field of vehicle vibration damping devices, and particularly relates to an integrated composite suspension actuator and a control method thereof. The vibration reduction device is novel and reasonable in design, can realize better vibration reduction under different working condition modes, can recover vibration energy, and is convenient to use, wide in use prospect and convenient to popularize and use.

Description

Integrated compound suspension actuator and its control method

technical field

The invention belongs to the technical field of vehicle damping devices, and in particular relates to an integrated composite suspension actuator and a control method thereof.

Background technique

The passive suspension widely used at present is composed of dampers and elastic elements, and its stiffness and damping cannot be changed. The passive suspension has no control, no energy input, low cost, high reliability, and simple design, but its comprehensive performance is poor. It can only achieve the optimal vibration reduction effect under special road conditions. The elastic characteristics of the air suspension are nonlinear and self-adaptive, which can keep the bias frequency of the sprung mass of the car relatively stable under load changes. Compared with the traditional suspension, it has the advantages of light weight, small internal friction, and isolation The advantages of good vibration and noise reduction characteristics enable the car with air suspension to obtain good ride comfort and road friendliness (small wheel dynamic load) during operation, which has important research significance. As "energy saving and environmental protection" has increasingly become a topic of widespread concern, lightweight is also widely used in the field of ordinary cars. Under the premise of high strength and safety performance, the curb weight of the car should be reduced as much as possible, so as to improve the power performance of the car, reduce fuel consumption, and reduce exhaust pollution. Experiments have proved that if the weight of the vehicle is reduced by 10%, the fuel efficiency can be increased by 6%-8%; the fuel consumption per 100 kilometers can be reduced by 0.3-0.6 liters for every 100 kg reduction in the curb weight of the vehicle; the fuel consumption can be reduced by 0.7 liters if the weight of the vehicle is reduced by 1%. %. At present, due to the needs of environmental protection and energy saving, the lightweight of automobiles has become the trend of the development of automobiles in the world. Suspension system is one of the important parts of the car body. How to achieve lightweight has become a problem that cannot be ignored in the development of the whole vehicle. Realizing the lightweight of the suspension is an important way to realize the lightweight of the car, and the lightweight of the suspension system Quantitative processing methods include optimizing structural dimensions, using high-strength materials, utilizing integration and modularization technologies, and adopting advanced processes.

Contents of the invention

The technical problem to be solved by the present invention is to provide an integrated composite suspension actuator for the above-mentioned deficiencies in the prior art.

In order to achieve the above object, the technical solution adopted by the present invention is: an integrated composite suspension actuator, including an actuator body and an actuator control system, characterized in that the actuator body includes a ball screw subassembly and an air spring assembly, the ball screw subassembly includes a screw sleeve, a screw that passes through the screw sleeve axially upwards and is fixedly connected to the fixed support seat, and a piston rod that is fixedly connected to the lower end of the screw through a bearing , the piston fixedly connected to the lower end of the piston rod, the floating piston arranged under the piston and inside the screw sleeve, and the buffer base arranged under the floating piston and inside the screw sleeve, the screw sleeve includes The inner tube of the screw sleeve and the outer tube of the screw sleeve forming the air flow channel, the upper part of the inner tube of the screw sleeve and the outer tube of the screw sleeve is provided with air holes C and air holes D, and the inner tube of the screw sleeve A piston cavity is formed inside the tube for the reciprocating movement of the piston. A floating air chamber is formed between the floating piston and the buffer base. The lower end of the tube is connected to the fixed base; the air spring assembly includes a rubber air bag, an air bag upper sealing plate is arranged on the upper end of the rubber air bag, and a flexible support frame is arranged between the rubber air bag and the outer tube of the lead screw sleeve. The air bag upper seal The inside of the plate is hollow and embedded with a fixed support seat. The upper end of the upper sealing plate of the airbag is fixedly connected with the cage. The cage and the upper sealing plate of the airbag are provided with an air hole A, and an air source pipeline is connected to the air hole A. The cage A brushless DC motor is arranged inside.

The upper end of the airbag upper sealing plate is threadedly connected with the retainer by screws, the airbag upper sealing plate is flange-connected with the rubber airbag, and the inner hollow of the airbag upper sealing plate is welded to the fixed support seat.

The upper end of the screw is fixedly connected to the output end of the shaft coupling, the lower end of the screw is fixedly connected to the piston rod through a bearing, and the surface of the screw is provided with threads.

The air hole A is a channel for the external air source to inflate and deflate the rubber airbag, and the air hole B, air hole C, and air hole D are channels for realizing air flow between the rubber airbag and the floating air chamber.

The actuator control system includes an actuator controller, a brushless DC motor drive circuit, a power inverter circuit, a brushless DC motor, a rectifier filter circuit, a DC/DC conversion circuit, a supercapacitor, a solenoid valve drive circuit, a second A variable voltage source circuit, a second variable voltage source circuit, a first relay, a second relay, a third relay, and a fourth relay. The input terminals of the actuator controller are connected with a displacement sensor, a vehicle speed sensor, a height sensor, sprung mass acceleration sensor, sprung mass displacement sensor, unsprung mass displacement sensor and air pressure sensor, the first relay is connected between the storage battery and the first variable voltage source circuit that supplies power to the solenoid valve driving circuit, so The second relay is connected between the battery and the second variable voltage source circuit that supplies power to the drive circuit of the brushless DC motor, the third relay is connected between the rectification filter circuit and the DC/DC conversion circuit, and the brushless DC motor It is connected with the output terminal of the motor driver comprising a brushless DC motor drive circuit and a power inverter circuit, the power inverter circuit is connected with the output terminal of the brushless DC motor drive circuit, and the rectification and filtering circuit is connected with the output terminal of the brushless DC motor The DC/DC conversion circuit is connected to the supercapacitor, the output end of the solenoid valve driving circuit is connected to the input end of the solenoid valve switch, and the first variable voltage source circuit and the second variable voltage source circuit are respectively connected to the The output terminal of the controller is connected.

The control method of integral compound suspension actuator is characterized in that, the method comprises the following specific steps:

Step 1. Data collection: The actuator controller periodically samples the displacement of the unevenness of the road surface, the real-time height of the vehicle body, the air pressure in the air spring, the acceleration of the sprung mass, the displacement of the sprung mass, and the displacement of the unsprung mass; The sprung mass displacement obtained by sampling i is denoted as x _1i , and the unsprung mass displacement obtained by sampling ith is denoted as x _2i , where the value of i is a non-zero natural number;

Step II: During the running of the vehicle, collect the vehicle speed signal, sprung mass displacement signal and unsprung mass displacement signal, and the actuator controller obtains the vehicle speed signal v _i and the sprung mass Displacement signal x _1i and unsprung mass displacement signal x _2i are analyzed and processed. When RMS(x _1i -x _2i )>0.035mm, the road surface of the vehicle is poor, the vehicle body is in high position mode, and the target vehicle height is 250mm+25mm ;When RMS(x _1i -x _2i )<0.035mm, and v _i <90km/h, the vehicle body is in the neutral mode, and the target vehicle height is 250mm; when v _i ≥90km/h, when the vehicle is running at high speed, the body In the low position mode, the target vehicle body height is 250mm-25mm; the actuator controller controls the inflation and deflation of the rubber airbag through the opening and closing of the solenoid valve switch, so as to realize the control of the vehicle body target height;

Step III. In the corresponding altitude mode, collect the sprung mass acceleration signal, sprung mass displacement signal and unsprung mass displacement signal respectively, and the actuator controller invokes the hybrid ceiling control module to analyze the sampled signals processing, the ideal active control force U _i of the suspension actuator at the i-th sampling is obtained, and the controller controls the brushless DC motor to input current to the ball screw sub-assembly to realize the matching control of the damping force of the suspension actuator .

The third step specifically includes the following steps:

根据混合天地棚控制算法计算公式F_i′＝βF_sky+(1-β)F_gnd计算得到第i次采样得到的车速信号v_i和速度

对应的车辆悬架混合天地棚控制下的主动控制力F_i′，其中，

c_sky为天棚控制阻尼系数；c_gnd为地棚控制阻尼系数，β值根据悬架系统在不同模式下的不同控制目标取选择不同，高位模式时选取β＝0.65；中位模式时选取β＝0.5；低位模式时选取β＝0.45；A1. When the vehicle is running under different working conditions, the upper controller in the actuator controller analyzes and processes the vehicle speed signal v _i , displacement x _1i , and x _2i obtained from the i-th sampling to obtain the speed signal

According to the calculation formula F _i ′=βF _sky +(1-β)F _gnd of the hybrid sky-ground canopy control algorithm, the vehicle speed signal v _i and speed obtained from the i-th sampling are obtained

The corresponding active control force F _i ′ under the control of the vehicle suspension hybrid ceiling, where,

c _sky is the ceiling control damping coefficient; c _gnd is the ground roof control damping coefficient, the β value is selected according to the different control objectives of the suspension system in different modes, select β=0.65 for the high position mode; select β=0.65 for the middle position mode 0.5; select β=0.45 in low mode;

计算得到第i次采样时无刷直流电机的输入电流I_i，其中，L为滚珠丝杠的导程，K_T为无刷直流电机的电磁转矩系数；作动器控制器控制第二继电器接通，第一继电器、第三继电器及第四继电器都处于未接通状态，蓄电池给第二可变电压源电路供电，第二可变电压源电路给无刷直流电机驱动电路供电驱动无刷直流电机工作，作动器控制器通过控制无刷直流电机回路中的等效电阻，改变电机的电磁力矩，从而输出一个可控的阻尼力

实现滚珠丝杠作动器的匹配控制，式中，R_n为馈能电路等效电阻，K_T为电机的电磁转矩系数,L为滚珠丝杠的导程。A2, the middle and lower controllers of the actuator controller according to the formula

Calculate the input current I _i of the brushless DC motor at the i-th sampling, where L is the lead of the ball screw, K _T is the electromagnetic torque coefficient of the brushless DC motor; the actuator controller controls the second relay connected, the first relay, the third relay and the fourth relay are not connected, the battery supplies power to the second variable voltage source circuit, and the second variable voltage source circuit supplies power to the brushless DC motor drive circuit to drive the brushless When the DC motor works, the actuator controller changes the electromagnetic torque of the motor by controlling the equivalent resistance in the brushless DC motor circuit, thereby outputting a controllable damping force

Realize the matching control of the ball screw actuator, where R _n is the equivalent resistance of the energy feed circuit, K _T is the electromagnetic torque coefficient of the motor, and L is the lead of the ball screw.

The specific process of realizing the matching control of the ball screw actuator in the step A2 includes:

的大小；Step B1, actuator controller calculation

the size of;

的计算结果与0进行大小比较，当

时，判断出滚珠丝杠处于阻尼匹配模式；当

时，判断出滚珠丝杠处于馈能工作模式。Step B2, the actuator controller will

The calculation result of is compared with 0, when

When , it is judged that the ball screw is in the damping matching mode; when

, it is judged that the ball screw is in the energy feeding mode.

The output signal of the actuator controller controls the energization of the third relay and the fourth relay, so that the electric energy generated by the brushless DC motor can be converted into a one-way direct current through the rectification and filtering circuit, and then charged to the supercapacitor after being boosted by the DC/DC conversion circuit , to achieve the recovery of vibration energy.

Compared with the prior art, the present invention has the following beneficial effects:

(1) The integrated composite suspension actuator of the present invention rationally integrates the ball screw type suspension actuator and the air spring with adjustable height and stiffness, and is a kind of vehicle body height adjustment and damping force matching control and A new vehicle shock absorber with integrated energy recovery function has compact structure, small volume and easy installation.

(2) The integrated composite suspension actuator of the present invention adjusts the body height of the car by adjusting the air spring, and improves the stability and smoothness of the car by changing the adjustable damping force of the ball screw, and the ball screw reciprocates The characteristics are suitable for automotive suspension systems.

(3) The integrated composite suspension actuator of the present invention can use the ball screw subassembly structure to realize damping force control when working in different height modes, and meet the different control requirements of the suspension in different modes. By changing the control current, To change the adjustable damping force of the ball screw, realize the matching control of the damping force of the actuator, avoid changing the damping force by changing the size of the orifice in the traditional air spring, improve the convenience of adjustment, and make the integrated composite suspension actuate The device is in the best vibration damping state, ensuring the stability of the vehicle and the comfort of the ride.

(4) In the integrated composite suspension actuator of the present invention, the suspension vibration energy recovered under the energy-feeding working mode in the matching control of the ball screw can be used for the matching control of the suspension actuator, reducing the energy consumption.

(5) In the control method of the integrated composite suspension actuator of the present invention, the controller adopts the hybrid sky-ground control method to analyze and process the sprung mass acceleration, sprung mass displacement and unsprung mass displacement obtained by the controller to obtain the ball wire The ideal damping force required by the bar, using the hybrid ceiling control method, makes the control of the integrated composite suspension actuator have a certain degree of self-adaptability and robustness, and ensures that the integrated composite suspension actuator has good stability Sex, good control effect.

Description of drawings

FIG. 1 is a schematic structural view of the integrated composite suspension actuator of the present invention.

Fig. 2 is a schematic diagram of the circuit connection relationship between the actuator controller and other parts of the present invention.

In the figure, 1—cage; 2—gas source pipe; 3—air hole A; 4—screw; 5—sealing plate on the airbag; 6—air hole C; 7—lead screw nut; 8—rubber air bag; 9—lead screw Sleeve outer tube; 10—lead screw sleeve inner tube; 11—flexible support frame; 12—floating piston; 13—floating air chamber; 14—buffer base; 15—fixed base; 16—air hole B; 17—piston; 18—piston rod; 19—bearing; 20—screw; 21—sealing ring; 22—air hole D; 23—buffer block; 24—fixed support seat; 25—coupling; 26—brushless DC motor; 27— Air compressor; 28—air storage tank; 29—connecting pipe; 30—filling and deflation of rubber air bag; 31—solenoid valve switch; 32—solenoid valve drive circuit; 33—supercapacitor; 34—battery; 35—first relay ; 36—the second relay; 37—the first variable voltage source circuit; 38—the second variable voltage source circuit valve; 39—the brushless DC motor drive circuit; 40—the power inverter circuit; 41—the fourth relay; 42—three-phase bridge power inverter circuit; 43—rectifier and filter circuit; 44—third relay; 45—DC/DC conversion circuit; 46—displacement sensor for road unevenness; 47—vehicle speed sensor; 48—body height sensor; 49—unsprung mass displacement sensor; 50—sprung mass displacement sensor; 51—sprung mass acceleration sensor; 52—air pressure sensor; 53—solenoid valve drive circuit; 54—controller;

detailed description

In order to further explain the technical means and effects of the present invention to achieve the intended purpose of the invention, the specific implementation, structure, features and effects of the application according to the present invention will be described in detail below in conjunction with the accompanying drawings and preferred embodiments. .

As shown in Figure 1, the integrated composite suspension actuator includes an actuator body and an actuator control system, wherein the actuator body includes a ball screw assembly and an air spring assembly, and the The ball screw subassembly includes a lead screw sleeve, a lead screw (20) that passes through the lead screw sleeve axially upwards and is fixedly connected to the fixed support seat (24), and is fixedly connected to the lead screw (20) through a bearing (19). ), the piston rod (18) at the lower end of the piston rod (18), the piston (17) fixedly connected to the lower end of the piston rod (18), the floating piston (12) arranged below the piston (17) and inside the screw sleeve, and the floating piston (12) arranged on the floating piston (12) the buffer base (14) below and in the lead screw sleeve, the lead screw sleeve includes a lead screw sleeve inner tube (10) and a lead screw sleeve outer tube (9) forming an air flow channel in the middle, Air hole C (6) and air hole D (22) are arranged on the upper part of the screw sleeve inner tube (10) and the screw sleeve outer tube (9), and a piston is formed in the screw sleeve inner tube (10). The cavity can be used for the reciprocating movement of the piston (17), and a floating air chamber (13) is formed between the floating piston (12) and the buffer base (14), and the buffer base (14) is arranged in the screw sleeve inner tube (10 ) lower end and center air hole B (16), and the lower end of the screw sleeve outer tube (9) is welded with a fixed base (15); the air spring assembly includes a rubber air bag (8), which is arranged on the rubber air bag (8 ) on the air bag upper sealing plate (5) at the upper end, a flexible support frame (11) is arranged between the rubber air bag (8) and the screw sleeve outer tube (9), and the inner air bag upper sealing plate (5) is hollow Embedded with a fixed support seat (24), the upper end of the upper sealing plate (5) of the airbag is fixedly connected with the cage (1), and the cage (1) and the upper sealing plate (5) of the airbag are provided with a penetrating air hole A (3 ), an air source pipeline (2) is communicated in the air hole A (3), and a brushless DC motor (26) is arranged in the cage (1).

The upper end of the airbag upper sealing plate (5) is threadedly connected with the cage (1) through a screw (4), the airbag upper sealing plate (5) is flange-connected with the rubber airbag (8), and the airbag upper sealing plate (5) The inner hollow is welded with the fixed support seat (24).

The upper end of the screw (20) is fixedly connected to the output end of the shaft coupling (25), the lower end of the screw (20) is fixedly connected to the piston rod (18) through a bearing (19), and the surface of the screw (20) Set with thread.

The air hole A (3) is the passage for the rubber air bag (8) to be inflated and deflated by an external air source, and the air hole B (16), air hole C (6) and air hole D (22) are the rubber air bag (8) and the floating Channels for air flow between chambers.

As shown in Figure 2, the actuator control system includes an actuator controller (54), a brushless DC motor drive circuit (39), a power inverter circuit (40), a brushless DC motor (26), a rectifier Filter circuit (43), DC/DC conversion circuit (45), supercapacitor (33), solenoid valve drive circuit (32), first variable voltage source circuit (37), second variable voltage source circuit (38) And the first relay (35), the second relay (36), the third relay (44), the fourth relay (41), the input terminal of the actuator controller (54) is connected with a displacement sensor (46), Vehicle speed sensor (47), height sensor (48), sprung mass acceleration sensor (51), sprung mass displacement sensor (50), unsprung mass displacement sensor (49) and air pressure sensor (52), the first The relay (35) is connected between the storage battery (34) and the first variable voltage source circuit (37) that supplies power to the solenoid valve drive circuit (32), and the second relay (36) is connected between the storage battery (34) and the power supply. Between the second variable voltage source circuit (38) powered by the brush DC motor drive circuit (39), the third relay (44) is connected between the rectification filter circuit (43) and the DC/DC conversion circuit (45), so The brushless DC motor (26) is connected to the output end of the motor driver comprising a brushless DC motor drive circuit (39) and a power inverter circuit (40), and the power inverter circuit (40) is connected to the brushless DC motor drive circuit The output terminal of (39) is connected, and described rectifying and filtering circuit (43) is connected with the output terminal of brushless DC motor (26), and described DC/DC conversion circuit (45) is connected with supercapacitor (33), and described electromagnetic The output end of the valve driving circuit (32) is connected with the input end of the solenoid valve switch (31), and the first variable voltage source circuit (37) and the second variable voltage source circuit (38) are respectively connected to the controller (54) output connection.

A control method for an integrated composite suspension actuator, characterized in that the method comprises the following steps:

Step 1, data collection: vehicle speed sensor (47) and road surface unevenness displacement sensor (46) carry out real-time monitoring to vehicle running speed and road surface unevenness displacement respectively, height sensor (48) detects the real-time height of vehicle body, air pressure sensor (52 ) monitor the air pressure in the rubber air bag (8) in real time, the sprung mass vertical acceleration sensor (51) monitors the sprung mass vertical acceleration in real time, and the sprung mass displacement sensor (50) monitors the sprung mass displacement in real time, The unsprung mass displacement sensor (49) detects the unsprung mass displacement in real time, and the actuator controller (54) respectively detects the unevenness displacement of the road surface, the real-time height of the vehicle body, the air pressure in the air spring, the sprung mass acceleration, the spring The sprung mass displacement and unsprung mass displacement are periodically sampled; the sprung mass displacement obtained by the i-th sampling is denoted as x _1i , and the unsprung mass displacement obtained by the i-th sampling is denoted as x _2i , where i The value of is a non-zero natural number;

Step II, during the running of the vehicle, the vehicle speed sensor (48) collects the vehicle speed signal, and the sprung mass displacement sensor (50) and the unsprung mass displacement sensor (49) respectively detect the sprung mass displacement signal and the unsprung mass displacement signal. The mass displacement signal is collected, and the actuator controller (54) analyzes and processes the vehicle speed signal v _i , displacement signal x _1i , and x _2i obtained from the i-th sampling. When RMS(x _1i -x _2i ) When >0.035mm, the road surface of the vehicle is poor, the body is in high mode, and the target body height is 250mm+25mm; when RMS(x _1i -x _2i )<0.035mm, and v _i <90km/h, the body is in the middle position mode, the target vehicle height is 250mm; when v _i ≥ 90km/h, when the vehicle is running at high speed, the vehicle body is in the low position mode, and the target vehicle height is 250mm-25mm; the actuator controller (54) switches through the solenoid valve ( 31) is disconnected and closed to control the inflation and deflation of the rubber air bag (8), so as to realize the control of the target height of the vehicle body;

Step III, in the corresponding altitude mode, the sprung mass acceleration sensor (51), the sprung mass displacement sensor (50) and the unsprung mass displacement sensor (49) respectively detect the sprung mass acceleration signal, sprung mass displacement signal and The unsprung mass displacement signal is collected, and the actuator controller (54) invokes the hybrid ceiling control module to analyze and process the sampled signal to obtain the ideal active force of the suspension actuator during the i-th sampling. To control the force U _i , the controller controls the brushless DC motor to input current to the ball screw subassembly to realize the matching control of the damping force of the suspension actuator. The specific steps are:

The specific working process is:

根据混合天地棚控制算法计算公式F_i′＝βF_sky+(1-β)F_gnd计算得到第i次采样得到的车速信号v_i和速度

对应的车辆悬架混合天地棚控制下的主动控制力F_i′，其中，

c_sky为天棚控制阻尼系数；c_gnd为地棚控制阻尼系数。Step 1. When the vehicle is running under different working conditions, the upper controller in the controller of the actuator (54) obtains the vehicle speed signal v _i obtained from the i-th sampling, the displacement x _1i obtained from the i-th sampling, x _2i for analysis and processing to get the speed signal

According to the calculation formula F _i ′=βF _sky +(1-β)F _gnd of the hybrid sky-ground canopy control algorithm, the vehicle speed signal v _i and speed obtained from the i-th sampling are obtained

The corresponding active control force F _i ′ under the control of the vehicle suspension hybrid ceiling, where,

c _sky is the ceiling control damping coefficient; c _gn d is the ground canopy control damping coefficient.

Its specific working process is:

对应的车辆悬架天棚控制下的阻尼力F_i′；Step A1: According to the formula F'=βF _sky +(1-β)F _gnd , the controller calculates the vehicle speed signal v _i obtained from the i-th sampling and the displacement x _1i and x _2i obtained from the i-th sampling for analysis and processing , get the speed signal

The corresponding damping force F _i ′ under the control of the vehicle suspension ceiling;

Step A2: The actuator controller (54) selects different β values according to the different control objectives of the suspension system in different modes, and obtains the corresponding ideal damping force in different modes, which is the damping matching control of the ball screw For reference; wherein, in the high position mode, the controller inflates the air spring to raise the vehicle body to the target height. Due to the poor road surface, the control goal of the suspension is mainly to improve ride comfort, that is, to reduce the spring load at this time. The mass acceleration is the control target, and the ideal damping force is mainly controlled by the ceiling, and β=0.65 is selected; in the neutral mode, the controller inflates or deflates the air spring to keep the body at the target height, and the neutral mode of the vehicle is the most Therefore, the control target of the suspension takes both ride comfort and driving safety into account, so β=0.5 is selected; in the low position mode, the controller deflates the air spring to lower the body to the target height. , the control target of the suspension is mainly to improve the driving safety, that is, to reduce the dynamic load of the tire as the control target at this time, and the ideal damping force is mainly controlled by the ground canopy, and β=0.45 is selected;

计算得到第i次采样时无刷直流电机(26)的输入电流I_i，其中，L为滚珠丝杠的导程，K_T为无刷直流电机的电磁转矩系数；作动器控制器(54)控制第二继电器(36)接通，第一继电器(35)、第三继电器(44)及第四继电器(41)都处于未接通状态，蓄电池给第二可变电压源电路(38)供电，第二可变电压源电路(38)给无刷直流电机驱动电路(39)供电驱动无刷直流电机(26)工作，作动器控制器(54)通过控制无刷直流电机回路中的等效电阻，改变电机的电磁力矩，从而输出一个可控的阻尼力

实现滚珠丝杠作动器的匹配控制，式中，R_n为馈能电路等效电阻，K_T为电机的电磁转矩系数,L为滚珠丝杠的导程。Step 2, the middle and lower layer controllers of the actuator controller according to the formula

Calculate and obtain the input current I _i of the brushless DC motor (26) when sampling for the ith time, wherein, L is the lead of the ball screw, and K _T is the electromagnetic torque coefficient of the brushless DC motor; the actuator controller ( 54) control the second relay (36) to be connected, the first relay (35), the third relay (44) and the fourth relay (41) are all in a non-connected state, and the storage battery supplies the second variable voltage source circuit (38 ) power supply, the second variable voltage source circuit (38) supplies power to the brushless DC motor drive circuit (39) to drive the brushless DC motor (26) to work, and the actuator controller (54) controls the brushless DC motor in the circuit The equivalent resistance of the motor changes the electromagnetic torque of the motor, thereby outputting a controllable damping force

Realize the matching control of the ball screw actuator, where R _n is the equivalent resistance of the energy feed circuit, K _T is the electromagnetic torque coefficient of the motor, and L is the lead of the ball screw.

Among them, the specific process of ball screw matching control is as follows:

的大小；Step B1, actuator controller (54) calculation

the size of;

的计算结果与0进行大小比较，当

时，判断出滚珠丝杠处于阻尼匹配模式；当

时，判断出滚珠丝杠处于馈能工作模式；Step B2, the actuator controller will

The calculation result of is compared with 0, when

When , it is judged that the ball screw is in the damping matching mode; when

, it is judged that the ball screw is in the energy feeding mode;

实现滚珠丝杠作动器的阻尼匹配，式中，R_n为馈能电路等效电阻，K_T为电机的电磁转矩系数,L为滚珠丝杠的导程。The ball screw is in the damping matching mode, and the actuator controller (54) changes the electromagnetic torque of the motor by controlling the equivalent resistance in the brushless DC motor circuit, thereby outputting a controllable damping force

Realize the damping matching of the ball screw actuator, where R _n is the equivalent resistance of the energy feed circuit, K _T is the electromagnetic torque coefficient of the motor, and L is the lead of the ball screw.

式中，R_n为馈能电路等效电阻；悬架系统被动馈能时的馈能能量W馈能为：

When the ball screw is in the energy feeding mode, the brushless DC motor (26) works as a generator, and the instantaneous energy feeding power P when the suspension system is passively feeding energy is:

In the formula, R _n is the equivalent resistance of the energy feeding circuit; the energy feeding energy W when the suspension system is passively feeding energy is:

The output signal of the actuator controller (54) controls the energization of the third relay (44) and the fourth relay (41), so that the electric energy generated by the brushless DC motor (26) is converted into a unidirectional direct current through a rectification and filtering circuit, and then After boosted by the DC/DC conversion circuit (45), the supercapacitor (33) is charged to realize the recovery of vibration energy. The specific working process is: when the piston (17) moves down or up, the piston (17) drives The piston rod (18) moves down or up, the piston rod (18) drives the ball screw nut (7) to move down or up through the screw (20), and the brushless DC motor (26) rotates counterclockwise or clockwise , the brushless DC motor (26) works as a generator, the brushless DC motor (26) generates an induced AC current, and the induced AC current passes through the rectification filter circuit (43) to rectify the AC power into a stable DC power, and then through the DC-DC conversion circuit (45) charge the supercapacitor (33) after boosting.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (5)

1. The control method of an integrated composite suspension actuator, the integrated composite suspension actuator includes an actuator body and an actuator control system, the actuator body includes a ball screw subassembly and an air The spring assembly, the ball screw sub-assembly includes a screw sleeve, which passes through the screw sleeve axially upwards and is fixedly connected to the screw (20) in the fixed support seat (24), and is fixedly connected by a bearing (19) The piston rod (18) at the lower end of the lead screw (20), the piston (17) fixedly connected to the lower end of the piston rod (18), the floating piston (12) arranged below the piston (17) and in the lead screw sleeve, A buffer base (14) arranged under the floating piston (12) and inside the screw sleeve, the screw sleeve includes an inner tube (10) of the screw sleeve and an outer tube of the screw sleeve forming an air flow channel in the middle (9), the inner tube (10) of the screw sleeve and the upper part of the outer tube (9) of the screw sleeve are provided with air holes C (6) and air holes D (22), and the inner tube of the screw sleeve (10 ) to form a piston cavity for the reciprocating movement of the piston (17), a floating air chamber (13) is formed between the floating piston (12) and the buffer base (14), and the buffer base (14) is arranged on the screw sleeve The lower end of the inner tube (10) is provided with an air hole B (16) in the center, and the lower end of the outer tube of the screw sleeve (9) is welded with a fixed base (15); the air spring assembly includes a rubber air bag (8), which is arranged on a rubber The air bag upper sealing plate (5) at the upper end of the air bag (8), a flexible support frame (11) is arranged between the rubber air bag (8) and the screw sleeve outer tube (9), and the air bag upper sealing plate (5 ) is embedded with a fixed support seat (24) in a hollow interior, and the upper end of the airbag upper sealing plate (5) is fixedly connected with the cage (1), and the cage (1) and the airbag upper sealing plate (5) are provided with through air holes A(3), the air hole A(3) is connected with an air source pipeline (2), and a brushless DC motor (26) is arranged in the cage (1); it is characterized in that the actuator controls The system includes an actuator controller (54), a brushless DC motor drive circuit (39), a power inverter circuit (40), a brushless DC motor (26), a rectification and filtering circuit (43), and a DC/DC conversion circuit ( 45), supercapacitor (33), solenoid valve driving circuit (32), first variable voltage source circuit (37), second variable voltage source circuit (38) and first relay (35), second relay ( 36), the third relay (44), the fourth relay (41), the input terminal of the actuator controller (54) is connected with a displacement sensor (46), a vehicle speed sensor (47), a height sensor (48), Sprung mass acceleration sensor (51), sprung mass displacement sensor (50), unsprung mass displacement sensor (49) and air pressure sensor (52), described first relay (35) is connected to storage battery (34) and given Between the first variable voltage source circuit (37) powered by the solenoid valve drive circuit (32), the second relay (36) is connected between the storage battery (34) and the drive circuit for the brushless DC motor. Between the second variable voltage source circuit (38) powered by circuit (39), the third relay (44) is connected between the rectification filter circuit (43) and the DC/DC conversion circuit (45), and the brushless DC The motor (26) is connected to the output end of the motor driver comprising a brushless DC motor drive circuit (39) and a power inverter circuit (40), and the power inverter circuit (40) is connected to the brushless DC motor drive circuit (39) The output end is connected, the rectification filter circuit (43) is connected with the output end of the brushless DC motor (26), the DC/DC conversion circuit (45) is connected with the supercapacitor (33), and the solenoid valve driving circuit ( 32) The output end is connected to the input end of the electromagnetic valve switch (31), and the first variable voltage source circuit (37) and the second variable voltage source circuit (38) are respectively connected to the output of the actuator controller (54) terminal connection; the method comprises the following specific steps: Step 1. Data collection: the actuator controller (54) periodically samples the unevenness displacement of the road surface, the real-time height of the vehicle body, the air pressure in the air spring, the acceleration of the sprung mass, the displacement of the sprung mass, and the displacement of the unsprung mass ; Denote the sprung mass displacement obtained by the i-th sampling as x _1i , and denote the unsprung mass displacement obtained by the i-th sampling as x _2i , where the value of i is a non-zero natural number; Step II: During the running of the vehicle, the vehicle speed signal, sprung mass displacement signal and unsprung mass displacement signal are collected, and the actuator controller (54) obtains the vehicle speed signal v _i , The sprung mass displacement signal x _1i and the unsprung mass displacement signal x _2i are analyzed and processed. When RMS(x _1i -x _2i )>0.035mm, the road surface of the vehicle is poor, the vehicle body is in high mode, and the target vehicle height is 250mm+25mm; when RMS(x _1i -x _2i )<0.035mm, and v _i <90km/h, the vehicle body is in the neutral mode, and the target vehicle height is 250mm; when v _i ≥90km/h, the vehicle runs at high speed , the vehicle body is in the low position mode, and the target vehicle body height is 250mm-25mm; the actuator controller (54) controls the inflation and deflation of the rubber airbag (8) through the disconnection and closure of the electromagnetic valve switch (31), so as to Realize the control of the target height of the vehicle body; Step III. In the corresponding height mode, the sprung mass acceleration signal, the sprung mass displacement signal and the unsprung mass displacement signal are respectively collected, and the actuator controller (54) calls the mixed sky and ground shed control module to sample it. The signal is analyzed and processed to obtain the ideal active control force U _i of the suspension actuator at the i-th sampling, and the actuator controller controls the brushless DC motor to input current to the ball screw assembly to actuate the suspension The damping force matching control of the device; Said step III comprises the following specific steps: A1. When the vehicle is running under different working conditions, analyze and process the vehicle speed signal v _i , displacement x _1i , and x _2i obtained from the i-th sampling to obtain the speed signal

According to the calculation formula F _i ′=βF _sky +(1-β)F _gnd of the hybrid sky-ground roof control algorithm, the vehicle speed signal v _i and speed can be obtained

The corresponding active control force F _i ′ under the control of the vehicle suspension hybrid ceiling, where,

c _sky is the ceiling control damping coefficient; c _gnd is the ground ceiling control damping coefficient; the β value is selected according to the different control objectives of the suspension system in different modes. In the high position mode, the ideal damping force is dominated by the ceiling control. = 0.65; in the middle position, the actuator controller inflates or deflates the air spring to keep the vehicle body at the target height, select β = 0.5; in the low position, the ideal damping force is mainly controlled by the floor shed, select β = 0.45 ; A2. According to the formula

Calculate and obtain the input current I _i of the brushless DC motor (26) when sampling for the ith time, wherein, L is the lead of the ball screw, and K _T is the electromagnetic torque coefficient of the brushless DC motor; the actuator controller ( 54) control the second relay (36) to be connected, the first relay (35), the third relay (44) and the fourth relay (41) are all in a non-connected state, and the storage battery supplies the second variable voltage source circuit (38 ) power supply, the second variable voltage source circuit (38) supplies power to the brushless DC motor drive circuit (39) to drive the brushless DC motor (26) to work, and the actuator controller (54) controls the brushless DC motor in the circuit The equivalent resistance of the motor changes the electromagnetic torque of the motor and outputs a controllable damping force

Realize the matching control of the ball screw actuator, where R _n is the equivalent resistance of the energy feed circuit, K _T is the electromagnetic torque coefficient of the motor, and L is the lead of the ball screw. 2. The control method of the integrated composite suspension actuator according to claim 1, characterized in that, the upper end of the upper sealing plate (5) of the air bag is threadedly connected with the cage (1) by a screw (4), so that The airbag upper sealing plate (5) is flange-connected with the rubber airbag (8), and the airbag upper sealing plate (5) is hollow inside and welded to the fixed support seat (24). 3. The control method of the integrated compound suspension actuator according to claim 1, characterized in that, the upper end of the leading screw (20) is fixedly connected with the output end of the shaft coupling (25), and the leading screw ( 20) The lower end is fixedly connected to the piston rod (18) through a bearing (19), and the surface of the screw (20) is provided with threads. 4. The control method of the integrated composite suspension actuator according to claim 1, characterized in that, the air hole A (3) is a passage for an external air source to charge and deflate the rubber air bag (8), and the Air hole B (16), air hole C (6), and air hole D (22) are channels for realizing air flow between the rubber air bag (8) and the floating air chamber. 5. The control method of the integrated composite suspension actuator according to claim 1, wherein the specific process of realizing the matching control of the ball screw actuator in the step A2 comprises: Step B1, actuator controller (54) calculation

the size of; Step B2, the actuator controller will

The calculation result of is compared with 0, when

When , it is judged that the ball screw is in the damping matching mode; when

, it is judged that the ball screw is in the energy feeding mode; The output signal of the actuator controller (54) controls the energization of the third relay (44) and the fourth relay (41), so that the electric energy generated by the brushless DC motor (26) is converted into a unidirectional direct current through a rectification and filtering circuit, The DC/DC conversion circuit (45) charges the supercapacitor (33) after boosting the voltage, realizing the recovery of vibration energy.

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