CN116176530A - Hydraulic pressure control method of integrated wire-control hydraulic brake system - Google Patents

Hydraulic pressure control method of integrated wire-control hydraulic brake system Download PDF

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Publication number
CN116176530A
CN116176530A CN202211660797.9A CN202211660797A CN116176530A CN 116176530 A CN116176530 A CN 116176530A CN 202211660797 A CN202211660797 A CN 202211660797A CN 116176530 A CN116176530 A CN 116176530A
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motor
voltage
current
target
torque
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靳立强
张奇祥
许杰
田梦杰
王凯
崔明萱
李建华
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Jilin University
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Jilin University
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T8/00—Arrangements for adjusting wheel-braking force to meet varying vehicular or ground-surface conditions, e.g. limiting or varying distribution of braking force
    • B60T8/17—Using electrical or electronic regulation means to control braking
    • B60T8/172—Determining control parameters used in the regulation, e.g. by calculations involving measured or detected parameters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/10—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release
    • B60T13/12—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with fluid assistance, drive, or release the fluid being liquid
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60T—VEHICLE BRAKE CONTROL SYSTEMS OR PARTS THEREOF; BRAKE CONTROL SYSTEMS OR PARTS THEREOF, IN GENERAL; ARRANGEMENT OF BRAKING ELEMENTS ON VEHICLES IN GENERAL; PORTABLE DEVICES FOR PREVENTING UNWANTED MOVEMENT OF VEHICLES; VEHICLE MODIFICATIONS TO FACILITATE COOLING OF BRAKES
    • B60T13/00—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems
    • B60T13/74—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive
    • B60T13/745—Transmitting braking action from initiating means to ultimate brake actuator with power assistance or drive; Brake systems incorporating such transmitting means, e.g. air-pressure brake systems with electrical assistance or drive acting on a hydraulic system, e.g. a master cylinder

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  • Engineering & Computer Science (AREA)
  • Transportation (AREA)
  • Mechanical Engineering (AREA)
  • Regulating Braking Force (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

The invention discloses a hydraulic pressure control method of an integrated wire control hydraulic brake system, which comprises the following steps: the actual rotation angle theta of the motor is compared with the corresponding rotation angle theta of the motor when the idle stroke of the motor pressure building cylinder is eliminated x0 Comparison is performed: if θ is less than or equal to θ x0 Determining a target mechanical rotating speed of the motor according to the actual position of the motor pressure building cylinder piston and the target position of the motor pressure building cylinder piston; if θ > θ x0 Determining a target mechanical rotating speed of the motor according to the actual braking pressure of the motor pressure building cylinder and the target braking pressure of the motor pressure building cylinder; determining a motor target torque shaft current according to the actual motor mechanical rotation speed and the motor target mechanical rotation speed; obtaining a first according to the actual torque shaft current of the motor, the actual exciting shaft current of the motor, the electric angular speed of the motor, the target torque shaft current of the motor and the target exciting shaft current of the motorA torque axis voltage and a first excitation axis voltage; and carrying out voltage constraint on the motor torque shaft and the motor excitation shaft to obtain a first corrected torque shaft voltage and a first corrected excitation shaft voltage, thereby controlling the permanent magnet synchronous motor to work.

Description

Hydraulic pressure control method of integrated wire-control hydraulic brake system
Technical Field
The invention belongs to the technical field of integrated wire-control hydraulic braking systems, and particularly relates to a hydraulic pressure control method of an integrated wire-control hydraulic braking system.
Background
The development of the electric and intelligent of the automobile chassis brings new requirements to the braking system, the traditional braking system represented by a vacuum booster is rapidly eliminated, a second-generation electronic hydraulic braking system represented by iBooster gradually occupies market share, but the integration level of iBooster is low, the coordination control difficulty with ESC is high, and therefore, the integrated wire control hydraulic braking system highly integrated in structure and control is promoted.
The integrated wire-control hydraulic braking system adopts an One-Box scheme, a vacuum booster is omitted, a brake master cylinder, sensors, a pedal feel simulator, a motor pressure building cylinder, a hydraulic control unit, a wire harness, a pipeline and the like are integrated into a whole, and the integrated wire-control hydraulic braking system has the advantages of being simple in structure, small in size, high in integration degree and the like, the motor pressure building cylinder becomes the only pressure source in a non-backup mode, the brake master cylinder is completely decoupled from the wheel cylinders, different functions can be realized through the same working mode, the control method is unified, and layering of upper software, interface design and interactive logic design of intelligent driving functions are facilitated. But is limited by factors such as brake fluid leakage, friction between transmission mechanisms, friction between brake fluid and brake pipelines, and the like, the integrated line-control hydraulic brake system has relatively complex nonlinear characteristics, which can influence the accuracy of brake pressure control. The hydraulic pressure control strategy of the integrated type wire control hydraulic brake system is a core link of the integrated type wire control hydraulic brake system for realizing 'quick pressure building and accurate pressure control' control, so that the development of the integrated type wire control hydraulic brake system is necessary to be studied in detail.
Disclosure of Invention
The invention aims to provide a hydraulic pressure control method of an integrated type wire control hydraulic brake system, which can effectively help the integrated type wire control hydraulic brake system to overcome friction of a transmission mechanism, nonlinear characteristics of a hydraulic system and the like, realize rapid and accurate control of hydraulic pressure, lay a foundation for active brake control of the integrated type wire control hydraulic brake system, and meet the requirements of electric and intelligent automobiles.
The technical scheme provided by the invention is as follows:
a hydraulic pressure control method of an integrated wire control hydraulic brake system comprises the following steps:
step one, acquiring an actual rotation angle theta of a permanent magnet synchronous motor, and comparing the actual rotation angle theta of the motor with a corresponding motor rotation angle when the idle stroke of a motor pressure building cylinder is eliminated
Figure BDA0004013791400000021
Comparison is performed:
if it is
Figure BDA0004013791400000022
Determining a target mechanical rotating speed of the motor according to the actual position of the motor pressure building cylinder piston and the target position of the motor pressure building cylinder piston;
if it is
Figure BDA0004013791400000023
Determining a target mechanical rotating speed of the motor according to the actual braking pressure of the motor pressure building cylinder and the target braking pressure of the motor pressure building cylinder;
step two, acquiring the actual mechanical rotation speed of the permanent magnet synchronous motor, and determining the motor target torque shaft current according to the actual mechanical rotation speed of the motor and the target mechanical rotation speed of the motor;
step three, acquiring an actual torque shaft current of a permanent magnet synchronous motor, an actual exciting shaft current of the motor and an electric angular speed of the motor, and obtaining a first torque shaft voltage and a first exciting shaft voltage according to the actual torque shaft current of the motor, the actual exciting shaft current of the motor, the electric angular speed of the motor, the target torque shaft current of the motor and the target exciting shaft current of the motor;
step four, voltage constraint is carried out on a motor torque shaft and a motor excitation shaft, and a first correction torque shaft voltage and a first correction excitation shaft voltage are obtained; and converting the first corrected torque shaft voltage and the first corrected exciting shaft voltage into a first PWM signal, and controlling the permanent magnet synchronous motor to work through the first PWM signal.
Preferably, the hydraulic pressure control method of the integrated brake-by-wire system further comprises:
in the third step, judging whether the flux weakening control is required to be started for the motor, if the flux weakening control is required to be started, calculating the current of the target torque shaft after current constraint and the current of the target excitation shaft after current constraint, and obtaining a second motor torque shaft voltage and a second motor torque shaft voltage according to the current of the target torque shaft after current constraint and the current of the target excitation shaft after current constraint;
in the fourth step, voltage constraint is carried out on the motor torque shaft and the motor excitation shaft to obtain a second corrected motor torque shaft voltage and a second corrected motor excitation shaft voltage; and converting the torque shaft voltage of the second modified motor and the excitation shaft voltage of the second modified motor into a second PWM signal, and controlling the permanent magnet synchronous motor to work through the second PWM signal.
Preferably, in the first step, when
Figure BDA0004013791400000031
Determining the target mechanical rotating speed of the motor based on a PID control algorithm; when->
Figure BDA0004013791400000032
And determining the target mechanical rotating speed of the motor based on a fuzzy PID control algorithm.
Preferably, in the second step, the motor target torque shaft current is calculated based on a synovial membrane variable structure control algorithm and a PI control algorithm by the following formula
Figure BDA0004013791400000033
Figure BDA0004013791400000034
Wherein J is the equivalent rotational inertia of the motor, P n Is the pole pair number, psi f Is a permanent magnet flux linkage, c 1 、c 2 Is a design parameter of the sliding mode surface,
Figure BDA0004013791400000035
for the derivative of the target mechanical rotational speed of the motor, +.>
Figure BDA0004013791400000036
For the derivative of the actual mechanical rotational speed of the motor, +.>
Figure BDA0004013791400000037
For the target mechanical rotational speed of the motor omega m For the actual mechanical rotational speed of the motor, < > is provided>
Figure BDA0004013791400000038
For the second derivative of the target mechanical rotational speed of the motor, < >>
Figure BDA0004013791400000039
For the derivative of the motor load torque,/>
Figure BDA00040137914000000310
The derivatives of disturbance torque including damping, friction, disturbance and the like are epsilon and delta as approach law parameters, and lambda is a synovial surface function.
Preferably, the synovial surface function is set as:
Figure BDA00040137914000000311
wherein ,
Figure BDA00040137914000000312
for motor desired speed and realismDerivative of the difference between the actual speed and the expected speed of the motor, c 1 、c 2 Is a design parameter of the sliding mode surface and is positive.
Preferably, in the third step, the first torque axis voltage and the first exciting axis voltage are obtained by the following formulas based on the PI controller:
Figure BDA00040137914000000313
in the formula ,uq For the first torque axis voltage u d For the first excitation axis voltage, K dp 、K qp Is proportional gain, K di 、K qi In order to integrate the gain,
Figure BDA00040137914000000314
target torque shaft current for motor, < >>
Figure BDA00040137914000000315
For the target exciting shaft current, i q I is the actual motor torque shaft current d For actual motor exciting shaft current, ω e For the electric angular velocity of the motor, L q Inductance, L, of motor torque shaft d Exciting shaft inductance of motor, psi f Is the permanent magnet flux linkage of the motor.
Preferably, in the third step, the method for judging whether the flux weakening control needs to be started for the motor is as follows:
calculating the difference between the maximum stator phase voltage and the output voltage of the current loop controller:
Figure BDA00040137914000000316
if Deltau < 0, starting weak magnetic control;
wherein ,ud For the first excitation axis voltage u q For the first torque axis voltage u dc Is the DC bus voltage.
Preferably, in said stepThirdly, calculating the current of the target torque shaft after current constraint through the following formula
Figure BDA0004013791400000041
Figure BDA0004013791400000042
And calculating the target excitation axis current after current constraint by the following formula
Figure BDA0004013791400000043
Figure BDA0004013791400000044
wherein ：
Figure BDA0004013791400000045
in the formula ,
Figure BDA0004013791400000046
target torque shaft current for motor, < >>
Figure BDA0004013791400000047
Correcting the torque axis current for weak magnetism, +.>
Figure BDA0004013791400000048
For the target excitation shaft current, +.>
Figure BDA0004013791400000049
Exciting shaft current is corrected for weak magnetism, +.>
Figure BDA00040137914000000410
Exciting shaft current is corrected for weak magnetism after current constraint; />
Figure BDA00040137914000000411
Is->
Figure BDA00040137914000000412
Minimum value of i s max For maximum current of motor, i drate Is the direct axis component of the rated current of the motor.
Preferably, in the third step, the method further includes:
determining the included angle theta between the voltage decreasing direction and the motor constant torque direction by a gradient decreasing method x ；
If theta is x Less than 90 DEG, calculating the weak magnetic correction torque shaft current through the following formula
Figure BDA00040137914000000413
Weak magnetic correction exciting shaft current
Figure BDA00040137914000000414
Figure BDA00040137914000000415
If theta is x > 90 DEG, the flux weakening correction torque shaft current is calculated by the following formula
Figure BDA00040137914000000416
Weak magnetic correction exciting shaft current
Figure BDA00040137914000000417
Figure BDA00040137914000000418
/>
in the formula ,λ1 、λ 2 Is the gain factor.
Preferably, in the fourth step, the calculation method of the first correction torque axis voltage and the first correction excitation axis voltage includes:
when (when)
Figure BDA0004013791400000051
When (I)>
Figure BDA0004013791400000052
When (when)
Figure BDA0004013791400000053
When (I)>
Figure BDA0004013791400000054
in the formula ,uq,lim A first corrected torque axis voltage; u (u) d,lim For the first corrected exciting shaft voltage u dc U is the voltage of the DC bus of the motor q For the first torque axis voltage u d Is the first excitation shaft voltage.
The beneficial effects of the invention are as follows:
(1) The position-pressure double-loop switching controller designed based on the PI control algorithm and the fuzzy PI control algorithm can effectively eliminate the influence of idle stroke of the motor pressure building cylinder and nonlinear characteristics of a hydraulic system, realize the rapid and accurate following of the actual pressure of the motor pressure building cylinder to different target pressures, improve the robustness of the system to external interference, and obtain a good control effect of rapid pressure building.
(2) The invention is based on a sliding film variable structure control algorithm adopting hyperbolic tangent function index approach rate and a speed loop controller designed by a nonlinear disturbance observer method, can effectively overcome the mechanical friction problem of a braking mechanism, weakens buffeting caused by unmeasurable disturbance torque, and improves the stability of a system.
(3) The current loop controller combining the voltage feedforward and the PI control algorithm, which is designed based on an inner film control theory, realizes the decoupling control of the current of the permanent magnet synchronous motor of the integrated line-control hydraulic braking system, and improves the control performance of the motor.
(4) The permanent magnet synchronous motor flux weakening controller designed based on the gradient descent method can enable the output rotating speed of the motor to break through the rated rotating speed of the motor, expand the rotating speed range of the motor and improve the response speed and the working efficiency of the motor.
Drawings
Fig. 1 is a block diagram of a hydraulic pressure control method of an integrated brake-by-wire system according to the present invention.
Fig. 2 is a schematic structural diagram of an integrated brake-by-wire system according to the present invention.
Fig. 3 is a limit circle, torque and voltage pattern of the surface-mounted permanent magnet synchronous motor according to the invention.
Fig. 4 is a graph of hydraulic pressure following an integrated brake-by-wire system at a ramp target pressure according to the present invention.
Fig. 5 is a graph of hydraulic pressure following error for an integrated brake by wire system at a ramp target pressure in accordance with the present invention.
Fig. 6 is a graph showing the speed following of a permanent magnet synchronous motor of the integrated brake-by-wire system under a slope target pressure according to the present invention.
Fig. 7 is a graph of the speed following error of the permanent magnet synchronous motor of the integrated brake-by-wire system under the slope target pressure according to the present invention.
Fig. 8 is a graph of hydraulic pressure following for an integrated brake-by-wire system at sinusoidal target pressure in accordance with the present invention.
Fig. 9 is a graph of hydraulic pressure following error for an integrated brake by wire system at sinusoidal target pressure in accordance with the present invention.
Fig. 10 is a graph showing the speed following curve of the permanent magnet synchronous motor of the integrated brake-by-wire system under the sinusoidal target pressure according to the present invention.
Fig. 11 is a graph of the speed following error of the permanent magnet synchronous motor of the integrated brake-by-wire system under sinusoidal target pressure according to the present invention.
Detailed Description
The present invention is described in further detail below with reference to the drawings to enable those skilled in the art to practice the invention by referring to the description.
As shown in fig. 1, the invention provides a hydraulic pressure control method of an integrated brake-by-wire system, which comprises the following specific implementation processes:
1. and designing the position-pressure double-loop switching controller of the integrated type line-control hydraulic braking system based on the PID control algorithm and the fuzzy PID control algorithm.
And designing a position loop controller based on a PID control algorithm, and designing a pressure loop controller based on a fuzzy PID control algorithm, namely designing a position-pressure double-loop switching controller. When the position-pressure double-ring switching controller is in the position ring
Figure BDA0004013791400000061
According to the actual position x of the motor pressure building cylinder piston and the set target position x * Output motor target mechanical speed +.>
Figure BDA0004013791400000062
When the position-pressure double-loop switching controller is in the pressure loop +.>
Figure BDA0004013791400000063
According to the actual braking pressure P and the target braking pressure P of the motor building cylinder * Output motor target mechanical speed +.>
Figure BDA0004013791400000064
The specific method comprises the following steps:
for a determined motor pressure cylinder, its idle stroke x 0 Is fixed, and the corresponding rotation angle for eliminating idle stroke is as follows:
Figure BDA0004013791400000065
in the formula ,
Figure BDA0004013791400000066
in order to eliminate the corresponding motor rotation angle when the motor builds the idle stroke of the pressure cylinder, h is the lead of the ball screw pair, i is the transmission ratio of the reduction gear pair, and x 0 Establishing an idle stroke of a pressure cylinder for the motor;
the motor pressure building cylinder pressure control strategy for position-pressure double-ring switching is as follows:when the stroke x of the motor building cylinder piston is less than or equal to x 0 (i.e
Figure BDA0004013791400000071
) When in use, the position ring control is adopted to quickly and accurately eliminate idle stroke; when the stroke x of the motor cylinder piston is larger than x 0 (i.e.)>
Figure BDA0004013791400000072
) When the pressure ring is used for control, the accurate and rapid pressure building capacity is ensured;
the position ring controller is:
Figure BDA0004013791400000073
in the formula ,ωm K is the actual rotation speed of the motor pp Is the proportionality coefficient of the position ring, K pi Is the integral coefficient of the position loop,
Figure BDA0004013791400000074
in order to eliminate the corresponding motor rotation angle when the motor builds the idle stroke of the pressure cylinder, theta is the actual rotation angle of the motor, and the motor can rotate at the mechanical rotation speed omega of the motor m Obtaining by integrating;
the pressure ring adopts a fuzzy PID control method, and the fuzzy rule is shown in table 1;
TABLE 1 fuzzy control table
Figure BDA0004013791400000075
The parameters adjusted by the fuzzy PI controller are as follows:
Figure BDA0004013791400000076
in the formula ,KP Is the proportionality coefficient of the pressure ring, K I Is the integral coefficient of the pressure ring, K P0 、K I0 Is the initial set point for the PI controller coefficient,ΔK P for the adjustment of the scaling factor ΔK I Is the adjustment quantity of the proportionality coefficient;
ω m (t)＝K P (P * -P)+K I ∫(P * -P)dt (4)
in the formula ,ωm K is the actual rotation speed of the motor P Is the proportionality coefficient of the pressure ring, K I Is the integral coefficient of the pressure ring, P * The target braking pressure of the motor building cylinder is the target braking pressure of the motor building cylinder, and P is the actual braking pressure of the motor building cylinder;
according to equations (2) and (4), the target motor mechanical rotational speed can be obtained
Figure BDA0004013791400000077
2. And designing a permanent magnet synchronous motor speed loop controller of the integrated type line-control hydraulic braking system by utilizing a sliding film variable structure control algorithm and a nonlinear interference observer method.
Speed loop controller is designed based on sliding film variable structure control algorithm and nonlinear disturbance observer method, and actual mechanical rotation speed omega of motor is calculated according to the actual mechanical rotation speed omega of motor m And motor target mechanical rotational speed
Figure BDA0004013791400000081
Output motor target torque shaft current +.>
Figure BDA0004013791400000082
At the same time, the nonlinear disturbance observer is designed to eliminate the unmeasurable disturbance torque T D Resulting in buffeting.
The specific method comprises the following steps:
the control variables and derivatives of the synovial membrane variable structure control are as follows:
Figure BDA0004013791400000083
where e is the difference between the desired speed and the actual speed of the motor,
Figure BDA0004013791400000084
for the target mechanical rotational speed of the motor omega m For the actual mechanical rotational speed of the motor, < > is provided>
Figure BDA0004013791400000085
For the derivative of the difference between the desired speed and the actual speed of the motor,/->
Figure BDA0004013791400000086
For the derivative of the target mechanical rotational speed of the motor, +.>
Figure BDA0004013791400000087
Is the derivative of the actual mechanical rotational speed of the motor;
the motor electromagnetic torque equation is:
Figure BDA0004013791400000088
in the formula ,Te For electromagnetic torque, P n Is the pole pair number, psi f I is a permanent magnet flux linkage q Is torque shaft current;
the mechanical motion equation of the motor is as follows:
Figure BDA0004013791400000089
wherein: j is the equivalent moment of inertia, omega of the motor m For the actual mechanical angular velocity of the motor, T e Is electromagnetic torque, T L For motor load torque, T D Disturbance torque including damping, friction, disturbance and the like;
deriving formula (5) and combining formulas (6) and (7) can obtain:
Figure BDA00040137914000000810
in the formula ,
Figure BDA00040137914000000811
for the derivative of the difference between the desired speed and the actual speed of the motor,/->
Figure BDA00040137914000000812
Is the derivative of the target mechanical rotational speed of the motor,
Figure BDA00040137914000000813
is the derivative of the actual mechanical rotation speed of the motor, J is the equivalent rotation inertia of the motor, and P n Is the pole pair number, psi f I is a permanent magnet flux linkage q For torque axis current, T L For motor load torque, T D For disturbance torque including damping, friction and disturbance, +.>
Figure BDA00040137914000000814
For the second derivative of the difference between the desired speed and the actual speed of the motor,/->
Figure BDA00040137914000000815
For the second derivative of the target mechanical rotational speed of the motor, < >>
Figure BDA00040137914000000816
Is the second derivative of the actual mechanical rotational speed of the motor, < >>
Figure BDA00040137914000000817
For the derivative of the torque axis current, +.>
Figure BDA0004013791400000091
T is the derivative of the motor load torque D For disturbance torque including friction, damping and disturbance, +.>
Figure BDA0004013791400000092
Derivatives of disturbance torque including damping, friction, disturbance, etc.;
the synovial surface function is selected as follows:
Figure BDA0004013791400000093
wherein lambda is the synovial surface function,
Figure BDA0004013791400000094
e is the difference between the expected speed and the actual speed of the motor, c is the derivative of the difference between the expected speed and the actual speed of the motor 1 、c 2 Is a design parameter of the sliding mode surface and is a positive value;
introducing a continuous smooth hyperbolic tangent function:
Figure BDA0004013791400000095
in the formula ,
Figure BDA0004013791400000096
is the derivative of the synovial surface function, lambda is the synovial surface function, epsilon and delta are approach law parameters and are positive values, χ is also positive value, and the smaller the value is, the +_>
Figure BDA0004013791400000097
The faster the speed approaching 1;
deriving the equation (9) and carrying the equation (10) to obtain the target torque shaft current of the motor
Figure BDA0004013791400000098
Figure BDA0004013791400000099
in the formula ,
Figure BDA00040137914000000910
the target torque shaft current of the motor is J is equivalent rotational inertia of the motor, and P n Is the pole pair number, psi f Is a permanent magnet flux linkage, c 1 、c 2 For the design parameters of the slip form surface, +.>
Figure BDA00040137914000000911
For the derivative of the target mechanical rotational speed of the motor, +.>
Figure BDA00040137914000000912
For the derivative of the actual mechanical rotational speed of the motor, +.>
Figure BDA00040137914000000913
For the target mechanical rotational speed of the motor omega m For the actual mechanical rotational speed of the motor, < > is provided>
Figure BDA00040137914000000914
For the second derivative of the target mechanical rotational speed of the motor, < >>
Figure BDA00040137914000000915
For the derivative of the motor load torque,/>
Figure BDA00040137914000000916
The derivative of disturbance torque including damping, friction, disturbance and the like is epsilon, delta as approach law parameters, and lambda as a synovial surface function;
the stability of the slip-form controller demonstrated the procedure as follows:
constructing Lyapunov functions as follows:
Figure BDA00040137914000000917
wherein V is Lyapunov function, and lambda is synovial surface function;
deriving the formula (12) to obtain:
Figure BDA00040137914000000918
wherein V is Lyapunov function, lambda is synovial surface function, epsilon and delta are approach law parameters and are positive values, and chi is also positive value;
since ε > 0, δ > 0, therefore
Figure BDA0004013791400000101
If and only if s=0, +.>
Figure BDA0004013791400000102
The instant evidence system is asymptotically stable;
from formulas (6) and (7), it can be seen that:
Figure BDA0004013791400000103
in the formula ,TD For disturbance torque including damping, friction, disturbance, etc., J is the equivalent moment of inertia of the motor,
Figure BDA0004013791400000104
is the derivative of the actual mechanical rotational speed of the motor, P n Is the pole pair number, psi f I is a permanent magnet flux linkage q For torque axis current, T L Load torque for the motor;
and (3) making:
Figure BDA0004013791400000105
in the formula ,
Figure BDA0004013791400000106
is T D ρ is a design parameter, p (ω) m ) Is a function to be set, and p (omega m ) The formula (16) needs to be satisfied;
Figure BDA0004013791400000107
wherein ρ is a design parameter, J is the equivalent moment of inertia of the motor,
Figure BDA0004013791400000108
is the derivative of the actual mechanical rotational speed of the motor, p (omega m ) To be set as a function omega m The actual mechanical rotation speed of the motor;
from formula (16):
p(ω m )＝-ρJω m (17)
in the formula ,p(ωm ) For the function to be set, ρ is a design parameter, J is the equivalent moment of inertia of the motor, ω m The actual mechanical rotation speed of the motor;
in summary, it is possible to obtain:
Figure BDA0004013791400000109
where z is a design function,
Figure BDA00040137914000001010
is T D ρ is a design parameter, J is the equivalent moment of inertia, ω of the motor m For the actual mechanical rotational speed of the motor, < > is provided>
Figure BDA00040137914000001011
For designing the derivative of the function +.>
Figure BDA00040137914000001012
Is T D Derivative of observed value>
Figure BDA00040137914000001013
Is the derivative of the actual mechanical rotational speed of the motor;
from formula (18), it is possible to obtain:
Figure BDA0004013791400000111
in the formula ,
Figure BDA0004013791400000112
for the derivative of the design function, ρ is the design parameter, P n Is the pole pair number, psi f I is a permanent magnet flux linkage q For torque axis current, T L For motor load torque, J is motor equivalent moment of inertia, < ->
Figure BDA0004013791400000113
Is the derivative of the actual mechanical rotation speed of the motor, z is a design function, omega m For the actual mechanical rotational speed of the motor u is the set value, the size of which is +.>
Figure BDA0004013791400000114
Thus, the nonlinear disturbance sensor is:
Figure BDA0004013791400000115
in the formula ,
Figure BDA0004013791400000116
for the derivative of the design function, ρ is the design parameter, z is the design function, ++>
Figure BDA0004013791400000117
Is T D U is a set value, and the size is +.>
Figure BDA0004013791400000118
J is the equivalent moment of inertia, omega of the motor m The actual mechanical rotation speed of the motor;
the convergence of the disturbance observer is demonstrated as follows:
when the system sampling step size is small, it can be considered that
Figure BDA0004013791400000119
Defining the observation error as follows:
Figure BDA00040137914000001110
in the formula ,
Figure BDA00040137914000001111
to observe errors, T D For disturbance torque including damping, friction and disturbance, +.>
Figure BDA00040137914000001112
Is T D Is a measurement of the observed value of (2);
deriving formula (21):
Figure BDA00040137914000001113
in the formula ,
Figure BDA00040137914000001114
for observing errors +.>
Figure BDA00040137914000001115
Derivative of disturbance torque for damping, friction and disturbance, etc., is +.>
Figure BDA00040137914000001116
Is T D ρ is the design parameter, +.>
Figure BDA00040137914000001117
Is an observation error;
thus, the observation error equation is:
Figure BDA00040137914000001118
in the formula ,
Figure BDA00040137914000001119
for the observation error ρ is the design parameter +.>
Figure BDA00040137914000001120
Is an observation error;
the solution of formula (23) is:
Figure BDA00040137914000001121
when ρ > 0, < >>
Figure BDA00040137914000001122
Exponentially converging on T D ；
According to equation (11), the motor target torque shaft current can be obtained
Figure BDA00040137914000001123
From equation (20), a nonlinear disturbance observer can be designed.
3. An inner film control theory is adopted to design a permanent magnet synchronous motor current loop controller of an integrated wire-controlled hydraulic braking system combining voltage feedforward and PI control.
Based on an inner film control theory, a current loop controller combining voltage feedforward and PI control is designed, and an actual torque shaft current i is received q Actual exciting shaft current i d Electric angular velocity omega of permanent magnet synchronous motor e Target torque shaft current output by speed loop controller
Figure BDA0004013791400000121
Exciting shaft current +.>
Figure BDA0004013791400000122
Obtaining the torque axis voltage u q (first torque shaft voltage) and exciting shaft voltage u d (first excitation shaft voltage).
The specific method comprises the following steps:
the voltage equation of the permanent magnet synchronous motor is:
Figure BDA0004013791400000123
in the formula ,uq For torque axis voltage, u d Is the excitation shaft voltage, R is the stator voltage, i q For torque axis current, i d For exciting shaft current, omega e Is the electric angular velocity L q Is torque axis inductance, L d The exciting shaft inductance is adopted;
from equation (24), the voltage u d 、u q In the presence of cross-coupled electromotive force-omega e L q i q 、-ω e L d i d And back electromotive force omega e ψ f This part can compensate the stator voltage as a feed-forward quantity, and for the rest of the stator voltage (temporarily called the decoupling electromotive force), the PI controller can be designed according to the in-mold control principle:
Figure BDA0004013791400000124
in the formula ,u′q For decoupling electromotive force for torque axis, u' d Decoupling electromotive force for excitation shaft, R is stator voltage, i q For torque axis current, i d For exciting shaft current, L q Is torque axis inductance, L d The exciting shaft inductance is adopted;
according to Laplace transformation and an inner membrane principle, the PI controller for designing decoupling electromotive force is as follows:
Figure BDA0004013791400000125
in the formula ,Kdp 、K qp Is proportional gain, K di 、K qi In order to integrate the gain,
Figure BDA0004013791400000126
target torque shaft current for motor, < >>
Figure BDA0004013791400000127
For the target exciting shaft current, i q For torque axis current, i d Exciting shaft current;
the current loop controller combining voltage feedforward and PI control is:
Figure BDA0004013791400000131
in the formula ,uq For torque axis voltage, u d For exciting shaft voltage, K dp 、K qp Is proportional gain, K di 、K qi In order to integrate the gain,
Figure BDA0004013791400000132
target torque shaft current for motor, < >>
Figure BDA0004013791400000133
For the target excitation shaft current, +.>
Figure BDA0004013791400000134
i q For torque axis current, i d For exciting shaft current, ω e Is the electric angular velocity L q Is torque axis inductance, L d Is the excitation axis inductance, ψ f Is a permanent magnet flux linkage;
from equation (27), the torque axis voltage u can be obtained q And exciting axis voltage u d 。
Thereafter, the torque axis voltage u q And exciting axis voltage u d After voltage constraint, the corrected torque shaft voltage u is output q,lim And correcting the exciting shaft voltage u d,lim After mathematical transformation and space vector pulse width modulation, PWM signals are generated, so that a driver is controlled to drive a permanent magnet synchronous motor of an integrated line-control hydraulic braking system to work, and the pressure of a brake master cylinder is regulated.
And then, designing a voltage restraint device and a permanent magnet synchronous motor flux weakening controller based on a gradient descent method.
Motor weak magnetic controller designed based on gradient descent method and receiving torque shaft voltage u output by current loop controller q (first torque shaft voltage) and exciting shaft voltage u d (first torque axis voltage), the modified excitation axis current after the flux weakening is outputted
Figure BDA0004013791400000135
And the corrected torque axis current after field weakening +.>
Figure BDA0004013791400000136
And determines exciting shaft current +.>
Figure BDA0004013791400000137
And torque axis current
Figure BDA0004013791400000138
The current loop controller receives the actual torque shaft current i q Actual exciting shaft current i d Electric angular velocity omega of permanent magnet synchronous motor e Target torque shaft current outputted by speed loop controller +.>
Figure BDA0004013791400000139
Corrected torque shaft current after field weakening +.>
Figure BDA00040137914000001310
The sum of the current-constrained target torque shaft currents +.>
Figure BDA00040137914000001311
Modified excitation axis current after field weakening +.>
Figure BDA00040137914000001312
Exciting shaft current after current constraint +.>
Figure BDA00040137914000001313
Exciting shaft current +.>
Figure BDA00040137914000001314
The added target exciting shaft current +.>
Figure BDA00040137914000001315
Obtaining the torque axis voltage u after the field weakening control q2 (second torque voltage) and field shaft voltage u after field weakening control d2 (second excitation shaft voltage).
Torque axis voltage u after field weakening control q2 (second torque voltage) and field shaft voltage u after field weakening control d2 (second exciting shaft voltage) is subjected to voltage constraint, and a corrected torque shaft voltage (second corrected torque shaft voltage) and a corrected exciting shaft voltage (second corrected torque shaft voltage) are output, and are subjected to mathematical transformationAnd generating PWM signals after the space vector pulse width modulation is changed, so that a driver is controlled to drive a permanent magnet synchronous motor of the integrated line-control hydraulic braking system to work, and the pressure of a brake master cylinder is regulated.
The specific method comprises the following steps:
the sum of the voltage vectors of the quadrature axis and the direct axis of the permanent magnet synchronous motor should be less than or equal to the maximum stator phase voltage due to the limitation of the voltage of the direct current bus, wherein the maximum stator phase voltage is as follows:
Figure BDA0004013791400000141
in the formula ,ulim For maximum stator phase voltage, u dc Is the voltage of a direct current bus;
when (when)
Figure BDA0004013791400000142
When the voltage constraint is not needed for the two shafts, the following steps are adopted:
Figure BDA0004013791400000143
in the formula ,uq For torque axis voltage, u d For exciting the shaft voltage u q,lim U is the corrected torque axis voltage after voltage constraint d,lim The voltage is corrected exciting shaft voltage after voltage constraint;
when (when)
Figure BDA0004013791400000144
When voltage constraint is needed for two axes, there are:
Figure BDA0004013791400000145
in the formula ,uq,lim U is the corrected torque axis voltage after voltage constraint d,lim For correcting exciting shaft voltage after voltage constraint, u dc For DC bus voltage, u q For torque axis voltage, u d The voltage is the exciting shaft voltage;
according to the current and voltage limit circles of the surface-mounted permanent magnet synchronous motor, the torque, the voltage increasing and decreasing direction and the motor running condition, the weak magnetic area can be divided into two parts: (1) a weak magnetic region I (FWR 1), wherein the motor runs along a constant torque curve at this stage; (2) weak magnetic region II (FWR 2), the motor at this stage along the maximum torque-to-voltage ratio curve; as shown in fig. 3.
Determining the weak magnetic area: θ x The angle is the included angle between the voltage decreasing direction and the constant torque direction, and can pass through theta x The angle judges the weak magnetic area of the motor: (1) when theta is as x When the angle is less than 90 degrees, the motor is positioned in a weak magnetic area I; (2) when theta is as x When the angle is more than 90 degrees, the motor is positioned in a weak magnetic area II;
the standard vectors of the constant torque direction and the voltage decreasing direction of the motor are respectively set as
Figure BDA0004013791400000146
Then:
Figure BDA0004013791400000147
in the formula ,
Figure BDA0004013791400000148
is the constant torque direction of the motor, T d Is the abscissa of the constant torque direction vector of the motor, T q Is the ordinate of the motor constant torque direction vector;
calculation by gradient descent method
Figure BDA0004013791400000149
Firstly, setting the cost function as follows:
Figure BDA0004013791400000151
wherein C is a cost function, u q For torque axis voltage, u d The voltage is the exciting shaft voltage;
when the motor rotation speed is higher, the stator winding voltage drop can be ignored, and an output voltage equation can be obtained:
Figure BDA0004013791400000152
in the formula ,uq For torque axis voltage, u d For exciting shaft voltage omega e Is the electrical angular velocity of the permanent magnet synchronous motor, L s Is inductance, i q For torque axis current, i d For exciting shaft current, ψ f Is a permanent magnet flux linkage;
the voltage decreasing direction is as follows:
Figure BDA0004013791400000153
/>
in the formula ,
Figure BDA0004013791400000154
i is the decreasing direction of voltage d For exciting shaft current, i q For torque axis current, L s Is inductance omega e U is the electrical angular velocity of the permanent magnet synchronous motor q For torque axis voltage, u d The voltage is the exciting shaft voltage;
the process is carried out by the steps of,
Figure BDA0004013791400000155
then:
Figure BDA0004013791400000156
in the formula ,
Figure BDA0004013791400000157
u is the decreasing direction of the voltage of the motor d For exciting the shaft voltage u q For torque axis voltage, ">
Figure BDA0004013791400000158
Theta can be obtained according to the formulas (31), (35) x The size of (2) is:
Figure BDA0004013791400000159
in the formula ,θx Is the included angle between the voltage decreasing direction and the constant torque direction,
Figure BDA00040137914000001510
is the constant torque direction of the motor, < >>
Figure BDA00040137914000001511
U is the decreasing direction of the voltage of the motor d For exciting shaft voltage, ">
Figure BDA00040137914000001512
After the weak magnetic area is determined, the current reference value needs to be corrected so as to achieve the purpose of weak magnetic control;
according to equation (28), the difference between the maximum stator phase voltage and the current loop controller output voltage is obtained as:
Figure BDA00040137914000001513
in the formula ,us max Is u dc For maximum stator phase voltage, u s The output voltage of the current loop controller is the voltage of a direct current bus, u d For exciting the shaft voltage u q Is the torque axis voltage;
the weak magnetic control opening condition is that Deltau < 0;
the standard vector of the motor maximum torque voltage ratio curve direction is
Figure BDA0004013791400000161
Then:
Figure BDA0004013791400000162
in the formula ,
Figure BDA0004013791400000163
a standard vector of the maximum torque voltage ratio curve direction of the motor;
in combination with equations (31) and (38), the current correction value is obtained as:
(1) Weak magnetic region I (FWR 1):
Figure BDA0004013791400000164
in the formula ,
Figure BDA0004013791400000165
is the corrected exciting shaft current after field weakening, lambda 1 The gain coefficient is the value range of 3-5; />
Figure BDA0004013791400000166
The current is corrected torque shaft current after weak magnetism;
(2) Weak magnetic region II (FWR 2):
Figure BDA0004013791400000167
in the formula ,
Figure BDA0004013791400000168
is the corrected exciting shaft current after field weakening, lambda 2 The gain coefficient is the value range of 1 to 3; />
Figure BDA0004013791400000169
The current is corrected torque shaft current after weak magnetism;
corrected excitation axis current after field weakening
Figure BDA00040137914000001610
When too small, the permanent magnet is at risk of demagnetizing, which needs to be limited to get +.>
Figure BDA00040137914000001611
/>
Figure BDA00040137914000001612
in the formula ,
Figure BDA00040137914000001613
corrected excitation axis current after weakening>
Figure BDA00040137914000001614
Exciting shaft current after current constraint, +.>
Figure BDA00040137914000001615
For correcting exciting shaft current after field weakening, < + >>
Figure BDA00040137914000001616
For current->
Figure BDA00040137914000001617
Minimum value of i s max For maximum current of motor, i drate Is the direct axis component of the rated current of the motor;
in the case of weak magnetic field, if the excitation shaft current increases negatively, the torque shaft current decreases positively, so for
Figure BDA00040137914000001618
Clipping:
Figure BDA00040137914000001619
in the formula ,
Figure BDA0004013791400000171
for current->
Figure BDA0004013791400000172
Maximum value of>
Figure BDA0004013791400000173
Target torque shaft current for motor, < >>
Figure BDA0004013791400000174
For the target excitation shaft current, +.>
Figure BDA0004013791400000175
Corrected excitation axis current after weakening>
Figure BDA0004013791400000176
Exciting shaft current after current constraint +.>
Figure BDA0004013791400000177
Exciting shaft current +.>
Figure BDA0004013791400000178
Adding the obtained target exciting shaft current, +.>
Figure BDA0004013791400000179
Target torque shaft current outputted for speed loop controller +.>
Figure BDA00040137914000001710
Corrected torque shaft current after field weakening +.>
Figure BDA00040137914000001711
Adding the obtained target torque shaft current;
the exciting shaft current input to the current loop controller is
Figure BDA00040137914000001712
The value is +.>
Figure BDA00040137914000001713
The input torque shaft current is +.>
Figure BDA00040137914000001714
Then, the current loop controller outputs the torque shaft voltage u after the field weakening control q2 (second torque voltage) and field shaft voltage u after field weakening control d2 (second excitation shaft voltage).
The current loop controller outputs torque shaft voltage u after weak magnetic control q2 (second torque axis voltage) and field axis voltage u after field weakening control d2 (second excitation shaft voltage) outputting a second corrected torque shaft voltage and a second corrected excitation shaft voltage (voltage constraint is still performed by adopting a calculation method in the formula (28) -the formula (30), and u in the formula is calculated by using the method q and ud Respectively replaced by u q2 and ud2 ) The method comprises the steps of carrying out a first treatment on the surface of the And generating PWM signals after mathematical transformation and space vector pulse width modulation, thereby controlling a driver to drive a permanent magnet synchronous motor of the integrated line-control hydraulic braking system to work and adjusting the pressure of a brake master cylinder.
FIG. 2 is a schematic diagram of an integrated brake-by-wire system, with the symbols shown in Table 2;
table 2 symbol meanings in the structural schematic diagram of an integrated brake-by-wire hydraulic brake system
Figure BDA00040137914000001715
The specific working principle of the integrated wire control hydraulic brake system is described as follows: (1) After a driver presses a brake pedal, the permanent magnet synchronous motor converts motor force into horizontal force acting on a push rod of a motor pressure building cylinder through a gear and a ball screw; (2) In a conventional braking mode, a brake master cylinder and each wheel cylinder in the integrated drive-by-wire hydraulic braking system are completely decoupled, a motor pressure building cylinder becomes the only pressure source in a non-backup mode, namely a servo motor becomes the only power source for pressure building, and the horizontal force acting on a push rod of the motor pressure building cylinder pushes a piston to complete pressure building; (3) The brake fluid in the motor pressure-building cylinder flows into each brake cylinder to generate wheel cylinder brake pressure, and the brake calipers are tightened to form wheel brake moment.
Examples
The combined simulation platform of the integrated line-control hydraulic braking system is built in MATLAB/Simulink and AMESim, and the hydraulic pressure control method of the integrated line-control hydraulic braking system designed by the patent is tested and verified.
Fig. 4 to 7 are hydraulic pressure control performance curves of the integrated brake-by-wire system under a set motor cylinder-building ramp target brake pressure. Two ramp target pressure signals are set, the amplitude pressure of the ramp target pressure signals is 80bar and 40bar respectively, the pressure rising gradient is 80bar/s, and the pressure falling gradient is 160bar/s. The simulation results of fig. 4 and 5 show that the actual pressure in the motor build cylinder achieves good follow-up of the ramp target pressure without overshoot and jitter. The position ring controller can quickly eliminate idle stroke of the motor pressure building cylinder within 0.1 s. When the position-pressure double-ring switching controller is switched from the position ring to the pressure ring, the pressure ring enables the actual pressure to rapidly increase and rapidly follow the upper target pressure; during the switching process, the pressure following error becomes large, reaching 6.8bar. But the pressure following error remains within 1.45bar throughout the pressure loop phase after a short abrupt change. Fig. 6 and 7 are a motor speed following curve and a speed following error curve, respectively, under the control of the speed loop controller. The permanent magnet synchronous motor used in the simulation herein had an idle speed of 2000 revolutions per minute. In the idle stroke stage of the motor pressure building cylinder, the position ring is eliminated, and the rotating speed of the motor is quickly pulled up to 3400 revolutions per minute after being subjected to field weakening control due to no load, so that the field weakening controller is effective, but in the stage, the speed following error is larger. When the position-pressure double loop switching controller is switched to the pressure loop, the motor speed following error is controlled within 20rpm except for a few moments. The performance requirement of 'quick decompression and accurate pressure control' of the integrated type drive-by-wire hydraulic braking system is basically met, the pressure building capacity of the system is ensured, and the actual use requirement is matched. The proposed method of hydraulic pressure control of an integrated brake-by-wire system has thus proved to be effective.
Fig. 8 to 11 are hydraulic pressure control performance curves of the integrated brake-by-wire system at a set motor build cylinder sinusoidal (bias 35bar, amplitude 35bar, frequency 1 Hz) target brake pressure. The simulation results of fig. 8 show that the actual pressure of the motor build cylinder of the integrated brake-by-wire system achieves good follow-up of the sinusoidal target pressure without overshoot and jitter. As shown in fig. 8 and 9, under the control of the field weakening strategy, the no-load rotation speed of the motor reaches 3400rpm, and the idle stroke of the motor pressure building cylinder is eliminated within 0.1 s. As shown in fig. 10 and 11, the step signal pressure following error reaches about 5bar at maximum, but after the position-pressure double-loop switching controller is switched to the pressure loop, it is always controlled within 1.2bar, and no phenomena such as overshoot and jitter occur. The speed following error of the motor is controlled to within 25rpm except for a very small number of moments. The performance requirement of 'quick decompression and accurate pressure control' of the integrated type drive-by-wire hydraulic braking system is basically met, the pressure building capacity of the system is ensured, and the actual use requirement is matched. The proposed method of hydraulic pressure control of an integrated brake-by-wire system has thus proved to be effective.
Although embodiments of the present invention have been disclosed above, it is not limited to the details and embodiments shown and described, it is well suited to various fields of use for which the invention would be readily apparent to those skilled in the art, and accordingly, the invention is not limited to the specific details and illustrations shown and described herein, without departing from the general concepts defined in the claims and their equivalents.

Claims (10)

1. The hydraulic pressure control method of the integrated wire control hydraulic brake system is characterized by comprising the following steps of:
step one, acquiring an actual rotation angle theta of a permanent magnet synchronous motor, and comparing the actual rotation angle theta of the motor with a corresponding motor rotation angle when the idle stroke of a motor pressure building cylinder is eliminated
Figure FDA0004013791390000011
Comparison is performed:
if it is
Figure FDA0004013791390000012
According toDetermining the target mechanical rotating speed of the motor by the actual position of the motor pressure building cylinder piston and the target position of the motor pressure building cylinder piston;
if it is
Figure FDA0004013791390000013
Determining a target mechanical rotating speed of the motor according to the actual braking pressure of the motor pressure building cylinder and the target braking pressure of the motor pressure building cylinder;
step two, acquiring the actual mechanical rotation speed of the permanent magnet synchronous motor, and determining the motor target torque shaft current according to the actual mechanical rotation speed of the motor and the target mechanical rotation speed of the motor;
step three, acquiring an actual torque shaft current of a permanent magnet synchronous motor, an actual exciting shaft current of the motor and an electric angular speed of the motor, and obtaining a first torque shaft voltage and a first exciting shaft voltage according to the actual torque shaft current of the motor, the actual exciting shaft current of the motor, the electric angular speed of the motor, the target torque shaft current of the motor and the target exciting shaft current of the motor;
step four, voltage constraint is carried out on a motor torque shaft and a motor excitation shaft, and a first correction torque shaft voltage and a first correction excitation shaft voltage are obtained; and converting the first corrected torque shaft voltage and the first corrected exciting shaft voltage into a first PWM signal, and controlling the permanent magnet synchronous motor to work through the first PWM signal.
2. The method of controlling hydraulic pressure of an integrated brake-by-wire system according to claim 1, further comprising:
in the third step, judging whether the flux weakening control is required to be started for the motor, if the flux weakening control is required to be started, calculating the current of the target torque shaft after current constraint and the current of the target excitation shaft after current constraint, and obtaining a second motor torque shaft voltage and a second motor torque shaft voltage according to the current of the target torque shaft after current constraint and the current of the target excitation shaft after current constraint;
in the fourth step, voltage constraint is carried out on the motor torque shaft and the motor excitation shaft to obtain a second corrected motor torque shaft voltage and a second corrected motor excitation shaft voltage; and converting the torque shaft voltage of the second modified motor and the excitation shaft voltage of the second modified motor into a second PWM signal, and controlling the permanent magnet synchronous motor to work through the second PWM signal.
3. The method according to claim 2, wherein in the first step, when
Figure FDA0004013791390000021
Determining the target mechanical rotating speed of the motor based on a PID control algorithm; when->
Figure FDA0004013791390000022
And determining the target mechanical rotating speed of the motor based on a fuzzy PID control algorithm.
4. The method according to claim 3, wherein in the second step, the motor target torque shaft current i is calculated based on a synovial variable structure control algorithm and a PI control algorithm by the following formula q * ：
Figure FDA0004013791390000023
Wherein J is the equivalent rotational inertia of the motor, P n Is the pole pair number, psi f Is a permanent magnet flux linkage, c 1 、c 2 Is a design parameter of the sliding mode surface,
Figure FDA0004013791390000024
for the derivative of the target mechanical rotational speed of the motor, +.>
Figure FDA0004013791390000025
For the derivative of the actual mechanical rotational speed of the motor, +.>
Figure FDA0004013791390000026
For the target mechanical rotational speed of the motor omega m For the actual mechanical rotational speed of the motor, < > is provided>
Figure FDA0004013791390000027
For the second derivative of the target mechanical rotational speed of the motor, < >>
Figure FDA0004013791390000028
For the derivative of the motor load torque,/>
Figure FDA0004013791390000029
The derivatives of disturbance torque including damping, friction, disturbance and the like are epsilon and delta as approach law parameters, and lambda is a synovial surface function. />
5. The method of controlling hydraulic pressure in an integrated brake-by-wire system according to claim 4, wherein the synovial surface function is set as:
Figure FDA00040137913900000210
wherein ,
Figure FDA00040137913900000211
e is the difference between the expected speed and the actual speed of the motor, c is the derivative of the difference between the expected speed and the actual speed of the motor 1 、c 2 Is a design parameter of the sliding mode surface and is positive.
6. The hydraulic pressure control method of an integrated brake by wire system according to claim 4 or 5, wherein in the third step, the first torque shaft voltage and the first exciting shaft voltage are obtained by the following formulas based on the PI controller:
Figure FDA00040137913900000212
in the formula ,uq For the first torque axis voltage u d For the first excitation axis voltage, K dp 、K qp Is proportional gain, K di 、K qi In order to integrate the gain,
Figure FDA00040137913900000213
target torque shaft current for motor, < >>
Figure FDA00040137913900000214
For the target exciting shaft current, i q I is the actual motor torque shaft current d For actual motor exciting shaft current, ω e For the electric angular velocity of the motor, L q Inductance, L, of motor torque shaft d Exciting shaft inductance of motor, psi f Is the permanent magnet flux linkage of the motor.
7. The method for controlling hydraulic pressure of an integrated brake-by-wire system according to claim 6, wherein in the third step, the method for determining whether the flux weakening control is required to be started for the motor is as follows:
calculating the difference between the maximum stator phase voltage and the output voltage of the current loop controller:
Figure FDA0004013791390000031
if Deltau < 0, starting weak magnetic control;
wherein ,ud For the first excitation axis voltage u q For the first torque axis voltage u dc Is the DC bus voltage.
8. The method according to claim 7, wherein in the third step, the current-constrained target torque shaft current is calculated by the following formula
Figure FDA0004013791390000032
Figure FDA0004013791390000033
And calculating the target excitation axis current after current constraint by the following formula
Figure FDA0004013791390000034
Figure FDA0004013791390000035
wherein ：
Figure FDA0004013791390000036
in the formula ,
Figure FDA0004013791390000037
target torque shaft current for motor, < >>
Figure FDA0004013791390000038
Correcting the torque axis current for weak magnetism, +.>
Figure FDA0004013791390000039
For the target excitation shaft current, +.>
Figure FDA00040137913900000310
Exciting shaft current is corrected for weak magnetism, +.>
Figure FDA00040137913900000311
Exciting shaft current is corrected for weak magnetism after current constraint; />
Figure FDA00040137913900000312
Is->
Figure FDA00040137913900000313
Minimum value of i smax For maximum current of motor, i drate Is the direct axis component of the rated current of the motor.
9. The method of controlling hydraulic pressure in an integrated brake-by-wire system according to claim 8, further comprising, in the third step:
determining the included angle theta between the voltage decreasing direction and the motor constant torque direction by a gradient decreasing method x ；
If theta is x Less than 90 DEG, calculating the weak magnetic correction torque shaft current through the following formula
Figure FDA00040137913900000314
And field weakening correction exciting shaft current +.>
Figure FDA00040137913900000315
Figure FDA0004013791390000041
If theta is x > 90 DEG, the flux weakening correction torque shaft current is calculated by the following formula
Figure FDA0004013791390000042
And field weakening correction exciting shaft current +.>
Figure FDA0004013791390000043
Figure FDA0004013791390000044
in the formula ,λ1 、λ 2 Is the gain factor.
10. The method according to claim 9, wherein in the fourth step, the first correction torque shaft voltage and the first correction excitation shaft voltage are calculated by:
when (when)
Figure FDA0004013791390000045
When (I)>
Figure FDA0004013791390000046
When (when)
Figure FDA0004013791390000047
When (I)>
Figure FDA0004013791390000048
in the formula ,uq,lim A first corrected torque axis voltage; u (u) d,lim For the first corrected exciting shaft voltage u dc U is the voltage of the DC bus of the motor q For the first torque axis voltage u d Is the first excitation shaft voltage.
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040100221A1 (en) * 2002-11-25 2004-05-27 Zhenxing Fu Field weakening with full range torque control for synchronous machines
CN108501911A (en) * 2018-03-09 2018-09-07 同济大学 A kind of vehicle integrated type electrical brake fluid system and stability control method
CN110371098A (en) * 2019-06-04 2019-10-25 天津英创汇智汽车技术有限公司 A kind of brushless motor control method based on intelligent electronic booster
WO2020093465A1 (en) * 2018-11-08 2020-05-14 中车永济电机有限公司 High-power direct-drive permanent magnet electric transmission system for electric locomotive
CN111934587A (en) * 2020-08-20 2020-11-13 广州金智为电气有限公司 Servo motor, driver, control system and control method thereof
CN113602274A (en) * 2021-08-30 2021-11-05 吉林大学 Intelligent vehicle longitudinal motion control method based on electric control power-assisted braking

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040100221A1 (en) * 2002-11-25 2004-05-27 Zhenxing Fu Field weakening with full range torque control for synchronous machines
CN108501911A (en) * 2018-03-09 2018-09-07 同济大学 A kind of vehicle integrated type electrical brake fluid system and stability control method
WO2020093465A1 (en) * 2018-11-08 2020-05-14 中车永济电机有限公司 High-power direct-drive permanent magnet electric transmission system for electric locomotive
CN110371098A (en) * 2019-06-04 2019-10-25 天津英创汇智汽车技术有限公司 A kind of brushless motor control method based on intelligent electronic booster
CN111934587A (en) * 2020-08-20 2020-11-13 广州金智为电气有限公司 Servo motor, driver, control system and control method thereof
CN113602274A (en) * 2021-08-30 2021-11-05 吉林大学 Intelligent vehicle longitudinal motion control method based on electric control power-assisted braking

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
张奇祥: "《面向智能驾驶的集成式线控液压制动系统控制策略研究》", 硕士学位论文, 12 August 2022 (2022-08-12), pages 35 - 52 *

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