CN106926660A - A kind of electromagnetic suspension system and its control method based on wheel rim driven motor vehicle - Google Patents

Abstract

The present invention provides a kind of electromagnetic suspension system and its control method based on wheel rim driven motor vehicle, and the system includes spring carried mass, flexible member, shock absorber, linear electric motors, wheel hub motor, unsprung mass, acceleration signal sensor, displacement transducer A, displacement transducer B and ECU；Methods described includes comfortable sexual norm, three kinds of mode of operations of safety profile and comprehensive sexual norm；The present invention coordinates control using inner and outer ring, inner ring control uses PI control algolithms, outer shroud control uses LQG control algolithms, compared to the monocyclic control that most researchers before are used, force tracing control mode based on LQG and PI controls can preferably track suspension real time kinematics state using feedback mechanism, and more effectively output target following power improves body vibrations.What the present invention set up simultaneously is the Three Degree Of Freedom electromagnetic suspension model based on wheel rim driven motor vehicle, and model structure is more complicated, it is considered to which factor is more, and can be applied on modern electric automobile, meets target for energy-saving and emission-reduction.

Description

A kind of electromagnetic suspension system and its control method based on wheel rim driven motor vehicle

Technical field

Patent of the present invention belongs to field of automobile safety, and in particular to a kind of electromagnetic suspension system based on wheel rim driven motor vehicle System and its control method.

Background technology

With continuing to develop for automotive engineering, requirement of the consumer to vehicle safety and comfortableness also more and more higher.Vapour In use, the transport condition such as load, speed, road conditions is more big changes car, and different operating modes are to ride comfort and manipulation The emphasis of stability requirement is different, and suspension performance also wants respective change.For example, ride comfort typically requires that suspension is softer, and When zig zag, brake hard and acceleration, scorch are manipulated, driving safety requires that suspension is harder again, to keep body gesture With the ground connection property of tire.Passive suspension is then difficult to meet under various transport conditions the high requirement to suspension property.Such It is required that under, many automobile energy-saving technologies arise at the historic moment, for example hydraulic pressure interconnection technique, semi- active control technology, Brake energy recovery Technology etc., these technologies improve the security and comfortableness of automobile to a certain extent.

Linear electric motors are electric rotating machines in one kind deformation of configuration aspects, its simple structure, efficiency high, armature and stator without The advantages of radial load, is in various fields extensively using development, particularly vehicle suspension aspect.Linear motor type electromagnetic suspension can To realize vehicle active damping by controlling linear electric motors, the controllability of suspension is considerably increased.

Chinese patent 201510645787.1 discloses a kind of design of vehicle active suspension LQG controller Optimal Control Forces Method, but LQG algorithms are solely simply employed, also it is worth considering in terms of the accuracy and validity of tracking power output；And And use simpler two degrees of freedom suspension system.

The content of the invention

In view of the shortcomings of the prior art, the present invention propose a kind of electromagnetic suspension system based on wheel rim driven motor vehicle and Its control method, coordinative role is controlled using the control of LQG outer shrouds and PI inner ring, and more accurately suspension is used as power with ensureing Control, reaches more preferable vehicle ride performance and security.

The technical scheme is that：A kind of electromagnetic suspension system based on wheel rim driven motor vehicle, including spring carried mass, Flexible member, shock absorber, linear electric motors, wheel hub motor, unsprung mass, acceleration signal sensor, displacement transducer A, displacement Sensor B and ECU；

The flexible member two ends are respectively fixedly connected with spring carried mass and wheel hub motor, and the two ends of shock absorber are respectively fixedly connected with Between spring carried mass and wheel hub motor, the other end of wheel hub motor is connected by bearing with unsprung mass；The straight-line electric mantle Inside flexible member, acceleration signal sensor is arranged on spring carried mass, and displacement transducer A is arranged on spring carried mass, Displacement transducer B is arranged on unsprung mass；

The ECU is electrically connected with acceleration signal sensor, displacement transducer A and displacement transducer B respectively, the ECU The acceleration signal of spring carried mass is gathered by acceleration signal sensor, the position of spring carried mass is gathered by displacement transducer A Shifting signal, the displacement signal of unsprung mass is gathered by displacement transducer B, and is analyzed and processed, and is obtained vehicle and is hanged in real time Frame dynamic parameter, is to be used as power according to using the control linear electric motors output of LQG algorithms with suspension dynamic parameter.

In such scheme, methods described includes comfortable sexual norm, three kinds of mode of operations of safety profile and comprehensive sexual norm； With riding comfort as control targe, the safety profile is grounded property as control targe to the comfortable sexual norm with tire, institute State comprehensive sexual norm and take into account riding comfort and tire ground connection property, linear electric motors are controlled using LQG algorithms to three of the above pattern Output is used as power；

The ECU of vehicle gathers the acceleration signal of spring carried mass by acceleration signal sensor, by displacement transducer A The displacement signal of spring carried mass is gathered, the displacement signal of unsprung mass is gathered by displacement transducer B, and analyzed and processed, Obtain the real-time suspension dynamic parameter of vehicle, the mode of operation that ECU enters according to the selection of the result of suspension dynamic parameter.

In such scheme, when vehicle body acceleration is more than 2m/s²When linear electric motors is operated in comfortable sexual norm；

Linear electric motors are made to be operated in safety profile when tyre dynamic load lotus is more than 2KN；

When the conditions set forth above are not met, linear electric motors are made to be operated in comprehensive sexual norm.

In such scheme, including the control of system outer shroud and system inner ring are controlled, and the system inner ring control is controlled using PI Algorithm, the system outer shroud control uses LQG control algolithms；

System controls to produce target control power to be input into control inner ring by LQG, and control inner ring carries out PI controls and is input into outstanding Frame model, Suspension Model is using real-time suspension dynamic parameter as control inner ring output, while the LQG controls of control outer shroud are fed back to, The output of real-time control linear electric motors is used as power, and suppresses suspension vibration.

In such scheme, the LQG control algolithms are specially：

1) the electromagnetic suspension model oscillatory differential equation with wheel hub motor is set up：

Wherein, Z_sIt is spring carried mass vertical deviation, Z_vIt is wheel hub motor vertical deviation, Z_tIt is unsprung mass vertical deviation, q It is road surface vertical deviation, K_sIt is elastic element rigidity, K_vIt is wheel hub motor equivalent stiffness, k_tIt is tire equivalent stiffness, C is vibration damping Device damped coefficient, F_aFor linear electric motors are used as power, F_vIt is motor vertical force, m_sFor m_vFor m_tFor；m_sIt is spring carried mass, m_vIt is wheel Hub motor quality, m_tIt is unsprung mass；

And express in the matrix form, such as following formula：

Wherein,

Wherein, W is white Gaussian noise input matrix, and U is control input matrix, i.e. W=[w], U=[F_a], Y=[F_V]；G₀ It is road roughness coefficient, U₀It is vehicle pace, f₀By frequency under, w is white Gaussian noise that average is zero

2) determine that LQG Con trolling index vehicle bodies vertical acceleration, suspension move the dynamic displacement of stroke, wheel and determine object function such as Under：

Wherein, q₁To take turns the weight coefficient of movement of the foetus displacement, q₂It is the weight coefficient of the dynamic stroke of suspension, q₃It is vehicle body acceleration Weight coefficient, T be a time cycle；

3) object function is rewritten into quadratic standard forms form：

Wherein：

4) according to Riccati equation

AK+KA^T+Q-KB-¹B^TK+FWF^T=0

Obtain gain matrix K=(k₁ k₂ k₃ k₄ k₅)；

5) according to gain matrix K and state variable X, the Optimal Control Force of linear electric motors output can be drawn：

In such scheme, suitable weight coefficient is chosen according to different mode；

When in comfortable sexual norm, then q₁=5.62, q₂=3283, q₃=21638；

When in safety profile, then q₁=1.03, q₂=50200, q₃=845000；

When in comprehensive sexual norm, then q₁=0.88, q₂=3000, q₃=38000.

In such scheme, according to the analysis of internal ring property in the PI algorithms, selected PI controller parameters are：Ratio is joined Number P=1.55, integral parameter I=0.7.

Compared with prior art, the beneficial effects of the invention are as follows：

1. using the Three Degree Of Freedom Suspension Model with wheel hub motor quality system, this model structure is carried suspension of the present invention first Go out, structure is novel, it is adaptable in the electric motor car of Direct wheel drives, the requirement of sustainable development is met, with very big environment protection significance.

2. the different operating modes for being travelled according to vehicle use different working modes, wherein comfortable sexual norm is with riding comfort Control targe, with tire ground connection property as control targe, comprehensive sexual norm takes into account both performances to safety profile, for three of the above Pattern simultaneously uses different weight coefficients in LQG controls, fast and accurately active control is carried out to suspension to reach, to protect The impression by bus of card occupant and safety by bus.

3. the present invention coordinates control using inner ring PI controls with outer shroud LQG controls, by feedback mechanism real-time control Linear electric motors output is used as power, and suppresses suspension vibration.

4. it is directed to electromagnet Suspension Model and proposes the improved LQG control algolithms matched with it, obtains straight line Motor exports Optimal Control Force, further improves the ride comfort and security of vehicle traveling.

Brief description of the drawings

Fig. 1 is the structure chart of the electromagnetic suspension based on Direct wheel drives in the present invention；

Fig. 2 is bicyclic force tracking system schematic in the present invention.

1- spring carried mass；2- flexible members；3- shock absorbers；4- linear electric motors；5- wheel hub motors；6- unsprung mass；7- adds Speed signal transducer；8- displacement transducers A；9- displacement transducers B.

Specific embodiment

The present invention is described in further detail with reference to the accompanying drawings and detailed description, but protection scope of the present invention It is not limited to this.

Fig. 1 is the structure chart of the electromagnetic suspension based on wheel rim driven motor vehicle in the present invention, based on wheel rim driven motor vehicle Electromagnetic suspension system include spring carried mass (1), flexible member (2), shock absorber (3), linear electric motors (4), wheel hub motor (5), Unsprung mass (6), acceleration signal sensor (7), displacement transducer A (8), displacement transducer B (9) and ECU.The elasticity unit Part (2) two ends are respectively fixedly connected with spring carried mass (1) and wheel hub motor (5), and the two ends of shock absorber (3) are respectively fixedly connected with spring charge material Between amount (1) and wheel hub motor (5), the other end of wheel hub motor (5) is connected by bearing with unsprung mass (6)；The straight line It is internal that motor (4) is placed on flexible member (2), acceleration signal sensor (7) on spring carried mass (1), displacement transducer A (8) on spring carried mass (1), displacement transducer B (9) is on unsprung mass (6)；Each sensor passes through can buses Transmission signal.

The ECU is electrically connected with acceleration signal sensor (7), displacement transducer A (8) and displacement transducer B (9) respectively Connect, the ECU gathers the acceleration signal of spring carried mass (1) by acceleration signal sensor (7), by displacement transducer A (8) displacement signal of collection spring carried mass (1), the displacement signal and wheel of unsprung mass (6) are gathered by displacement transducer B (9) Movement of the foetus load signal is simultaneously analyzed and processed, and obtains the real-time suspension dynamic parameter of vehicle, is that foundation is adopted with suspension dynamic parameter Control linear electric motors (4) to export with LQG algorithms to be used as power.

The formula of the tyre dynamic load lotus：F_d=(Z_t-q)*k_t

The present invention also provides a kind of control method of the electromagnetic suspension system based on wheel rim driven motor vehicle described in basis, bag Include comfortable sexual norm, three kinds of mode of operations of safety profile and comprehensive sexual norm.

Due to there is contradiction between vehicle ride comfort and tire ground connection property, behaviour can be sacrificed while ride comfort is improved Stability, vice versa, so invention sets three kinds of mode of operations respectively, wherein, comfortable sexual norm is to control with riding comfort Target, with tire ground connection property as control targe, comprehensive sexual norm takes into account both to safety profile, and three of the above pattern is used LQG control strategies simultaneously formulate corresponding weight coefficient and realize vehicle dynamic performance under different mode according to different mode Improve.

The ECU of vehicle gathers the acceleration signal of spring carried mass 1 by acceleration signal sensor 7, by displacement sensing Device A8 gathers the displacement signal of spring carried mass 1, and the displacement signal of unsprung mass 6 is gathered by displacement transducer B9, and is divided Analysis is processed, and obtains the real-time suspension dynamic parameter of vehicle, ECU according to suspension dynamic parameter (wheel movement of the foetus displacement, the dynamic stroke of suspension, Vehicle body acceleration) result selection enter mode of operation.

A. when vehicle body acceleration is more than 2m/s², now according to human body degree, occupant can experience larger shaking It is dynamic, linear electric motors is operated in comfortable sexual norm.

B. when tyre dynamic load lotus is more than 2KN, now vehicle tyre circular runout is larger, and vehicle stabilization traveling can be caused Influence, now makes linear electric motors be operated in safety profile.

C. when both conditions above-mentioned are unsatisfactory for, linear electric motors is operated in comprehensive sexual norm, take into account both performances, ensure Vehicle steadily is travelled.

Fig. 2 is bicyclic force tracking system schematic of the invention, and the control of control system inner ring uses PI control algolithms, outer shroud Control uses LQG control algolithms, and LQG controls produce target control power input control inner ring, and control inner ring carries out PI controls and defeated Enter Suspension Model, Suspension Model is using real-time suspension dynamic parameter as control inner ring output, while feeding back to the LQG controls of control outer shroud System.

The PI algorithms that inner ring control is used are specific as follows：

According to the analysis of internal ring property, selected PI controller parameters are：Scale parameter P=1.55, integral parameter I= 0.7, by system emulation, this parameter can make model system be used as power preferably track target control power, reduce systematic error, Ensure the accuracy that output is used as power.

Outer shroud controls used LQG algorithms specific as follows：

Electromagnetic suspension system dynamic differential equation with wheel hub motor is as follows：

Wherein, Z_sIt is spring carried mass vertical deviation, Z_vIt is wheel hub motor vertical deviation, Z_tFor unsprung mass (i.e. tire) hangs down To displacement, K_sIt is elastic element rigidity, K_vIt is wheel hub motor equivalent stiffness, k_tIt is tire equivalent stiffness, C is resistance of shock absorber system Number, F_aFor linear electric motors are used as power, F_vIt is motor vertical force, m_sFor m_vFor m_tFor；m_sIt is spring carried mass, m_vIt is wheel hub motor matter Amount, m_tIt is unsprung mass；

Road surface input model meets the filtering white noise that Gauss (normal state) is distributed using one, i.e.,：

Wherein G₀It is road roughness coefficient, U₀It is Vehicle Speed, w is white Gaussian noise, f₀It is cut-off frequency.

For the ease of using LQG algorithms, the above-mentioned differential equation is write as matrix form, i.e. following formula：

Wherein,

Wherein, W is white Gaussian noise input matrix, and U is control input matrix, i.e. W=[w], U=[F_a], Y=[F_V]；G₀ It is road roughness coefficient, U₀It is vehicle pace, f₀By frequency under, w is white Gaussian noise that average is zero

In electromagnetic suspension system, LQG controller object functions J is wheel movement of the foetus displacement, suspension dynamic stroke and vehicle body acceleration Weighted sum of squares integrated value, i.e.,：

Wherein, q₁To take turns the weight coefficient of movement of the foetus displacement, q₂It is the weight coefficient of the dynamic stroke of suspension, q₃It is vehicle body acceleration Weight coefficient, T be a time cycle.Pin will be had according to vehicle difference transport condition using different weights to different target To the improvement vehicle of property performance in a certain respect.

The weight coefficient that different mode is chosen is preferably as follows table：

Above formula object function is rewritten as quadratic standard forms form：

Wherein：

Gain matrix K is obtained using Riccati equation, Riccati equation form is as follows：

AK+KA^T+Q-KB-¹B^TK+FWF^T=0

According to gain matrix K and state variable X, the Optimal Control Force of linear electric motors output can be drawn：

The present invention coordinates control using inner and outer ring, and inner ring control uses PI control algolithms, and outer shroud control controls to calculate using LQG Method, compared to the monocyclic control that most researchers before are used, the force tracing control mode controlled based on LQG and PI can be utilized Feedback mechanism preferably tracks suspension real time kinematics state, and more effectively output target following power improves body vibrations.Simultaneously What the present invention set up is the Three Degree Of Freedom electromagnetic suspension model based on wheel rim driven motor vehicle, and model structure is more complicated, it is considered to because Element is more, and can be applied on modern electric automobile, meets the target of energy-saving and emission-reduction.

It should be understood that, although this specification is described according to each embodiment, but not each embodiment only includes one Individual independent technical scheme, this narrating mode of specification is only that for clarity, those skilled in the art will should say Used as an entirety, technical scheme in each embodiment can also be through appropriately combined, and forming those skilled in the art can be with for bright book The other embodiment of understanding.

Those listed above is a series of to describe illustrating only for possible embodiments of the invention in detail, They simultaneously are not used to limit the scope of the invention, all Equivalent embodiments made without departing from skill spirit of the present invention or change Should be included within the scope of the present invention.

Claims (7)

1. a kind of electromagnetic suspension system based on wheel rim driven motor vehicle, it is characterised in that including spring carried mass (1), elasticity unit Part (2), shock absorber (3), linear electric motors (4), wheel hub motor (5), unsprung mass (6), acceleration signal sensor (7), displacement Sensors A (8), displacement transducer B (9) and ECU；

Flexible member (2) two ends are respectively fixedly connected with spring carried mass (1) and wheel hub motor (5), the two ends point of shock absorber (3) It is not connected between spring carried mass (1) and wheel hub motor (5), the other end of wheel hub motor (5) is by bearing and unsprung mass (6) Connection；The linear electric motors (4) are placed on flexible member (2) inside, and acceleration signal sensor (7) is installed in spring carried mass (1) On, on spring carried mass (1), displacement transducer B (9) is on unsprung mass (6) for displacement transducer A (8)；

The ECU is electrically connected with acceleration signal sensor (7), displacement transducer A (8) and displacement transducer B (9) respectively, institute The acceleration signal that ECU gathers spring carried mass (1) by acceleration signal sensor (7) is stated, is adopted by displacement transducer A (8) The displacement signal of collection spring carried mass (1), the displacement signal of unsprung mass (6) is gathered by displacement transducer B (9), and is divided Analysis is processed, and obtains the real-time suspension dynamic parameter of vehicle, is according to using LQG algorithms control linear electric motors with suspension dynamic parameter (4) output is used as power.

2. it is a kind of according to claim 1 based on wheel rim driven motor vehicle electromagnetic suspension system control method, its feature It is, including comfortable sexual norm, three kinds of mode of operations of safety profile and comprehensive sexual norm；The comfortable sexual norm is easypro to take Adaptive is control targe, and the safety profile with tire ground connection property as control targe, take into account seating and relax by the comprehensive sexual norm Adaptive and tire ground connection property, control linear electric motors (4) output to be used as power three of the above pattern using LQG algorithms；

The ECU of vehicle gathers the acceleration signal of spring carried mass (1) by acceleration signal sensor (7), by displacement sensing The displacement signal of device A (8) collections spring carried mass (1), the displacement signal of unsprung mass (6) is gathered by displacement transducer B (9), And analyzed and processed, the real-time suspension dynamic parameter of vehicle is obtained, ECU enters according to the selection of the result of suspension dynamic parameter Mode of operation.

3. the control method of the electromagnetic suspension system based on wheel rim driven motor vehicle according to claim 2, its feature exists In,

When vehicle body acceleration is more than 2m/s²When linear electric motors (4) is operated in comfortable sexual norm；

Linear electric motors (4) are made to be operated in safety profile when tyre dynamic load lotus is more than 2KN；

When the conditions set forth above are not met, linear electric motors (4) are made to be operated in comprehensive sexual norm.

4. a kind of control method of the electromagnetic suspension system based on wheel rim driven motor vehicle according to Claims 2 or 3, it is special Levy and be, including the control of system outer shroud and system inner ring are controlled, the system inner ring control uses PI control algolithms, the system Outer shroud control uses LQG control algolithms；

System produces target control power to be input into control inner ring by LQG control algolithms, and control inner ring carries out PI controls and is input into outstanding Frame model, Suspension Model is using real-time suspension dynamic parameter as control inner ring output, while the LQG controls of control outer shroud are fed back to, Real-time control linear electric motors (4) output is used as power, and suppresses suspension vibration.

5. the control method of the electromagnetic suspension system based on wheel rim driven motor vehicle according to claim 4, its feature exists In the LQG control algolithms are specially：

1) the electromagnetic suspension model oscillatory differential equation with wheel hub motor is set up：

$m_s{\stackrel{\·\·}{Z}}_s+(Z_s-Z_v)K_s+({\stackrel{\·}{Z}}_s-{\stackrel{\·}{Z}}_v)C+F_a=0,$

$m_v{\stackrel{\·\·}{Z}}_v-(Z_s-Z_v)K_s-({\stackrel{\·}{Z}}_s-{\stackrel{\·}{Z}}_v)C-F_a+(Z_v-Z_t)K_v+F_v=0,$

$m_t{\stackrel{\·\·}{Z}}_t-(Z_v-Z_t)K_v+k_t(Z_t-q)-F_v=0,$

Wherein, Z_sIt is spring carried mass vertical deviation, Z_vIt is wheel hub motor vertical deviation, Z_tIt is unsprung mass vertical deviation, q is road Face vertical deviation, K_sIt is elastic element rigidity, K_vIt is wheel hub motor equivalent stiffness, k_tIt is tire equivalent stiffness, C hinders for shock absorber Buddhist nun's coefficient, F_aFor linear electric motors are used as power, F_vIt is motor vertical force, m_sIt is spring carried mass, m_vIt is wheel hub motor quality, m_tFor under spring Quality；

And express in the matrix form, such as following formula：

$\stackrel{\·}{X}=AX+BU+FW+CY$

Wherein,

$A=\left[\begin{array}{ccccccc}-\frac{C}{m_s}& \frac{-k_s}{m_s}& \frac{C}{m_s}& \frac{k_s}{m_s}& 0& 0& 0\\ 1& 0& 0& 0& 0& 0& 0\\ \frac{C}{m_v}& \frac{k_s}{m_v}& \frac{-C}{m_v}& \frac{-k_s-k_v}{m_v}& 0& \frac{k_v}{m_v}& 0\\ 0& 0& 1& 0& 0& 0& 0\\ 0& 0& 0& \frac{k_v}{m_t}& 0& \frac{-k_v-k_t}{m_t}& \frac{k_t}{m_t}\\ 0& 0& 0& 0& 1& 0& 0\\ 0& 0& 0& 0& 0& 0& -2{\mathrm{\πf}}_0\end{array}\right]$

$B=\[\begin{array}{ccccccc}-\frac{1}{m_s}& 0& -\frac{1}{m_v}& 0& 0& 0& 0\end{array}\]$

$C=\[\begin{array}{ccccccc}0& 0& -\frac{1}{m_v}& 0& \frac{1}{m_t}& 0& 0\end{array}\]$

$F=\[\begin{array}{ccccccc}0& 0& 0& 0& 0& 0& 2\mathrm{\π}\sqrt{G_0{U}_0}\end{array}\]$

Wherein, W is white Gaussian noise input matrix, and U is control input matrix, i.e. W=[w], U=[F_a], Y=[F_V]；G₀It is road Face irregularity coefficient, U₀It is vehicle pace, f₀By frequency under, w is white Gaussian noise that average is zero

2) determine that LQG Con trolling index vehicle bodies vertical acceleration, suspension move the dynamic displacement of stroke, wheel and determine that object function is as follows：

$J=\underset{T\→\mathrm{\∞}}{\lim }\frac{1}{T}{\∫}_0^T\[q_1{(z_s-z_g)}^2+q_2{(z_s-z_t)}^2+q_3\stackrel{\·\·}{{z_s}^2}\]dt$

Wherein, q₁To take turns the weight coefficient of movement of the foetus displacement, q₂It is the weight coefficient of the dynamic stroke of suspension, q₃It is adding for vehicle body acceleration Weight coefficient, T is a time cycle；

3) object function is rewritten into quadratic standard forms form：

$J=\underset{T\→\mathrm{\∞}}{\lim }\frac{1}{T}{\∫}_0^T\[X^{T}QX+U^{T}RU+2X^{T}NU\]dt$

Wherein：

$Q=\left[\begin{array}{ccccccc}0& 0& 0& 0& 0& 0& 0\\ 0& q_2+q_3\frac{{k_s}^2}{{m_s}^2}& 0& 0& 0& -q_2-q_3\frac{{k_s}^2}{{m_s}^2}& 0\\ 0& 0& 0& 0& 0& 0& 0\\ 0& 0& 0& 0& 0& 0& 0\\ 0& 0& 0& 0& 0& 0& 0\\ 0& -q_2-q_3\frac{{k_s}^2}{{m_s}^2}& 0& 0& 0& q_1+q_2+q_3\frac{{k_s}^2}{{m_s}^2}& -q_1\\ 0& 0& 0& 0& 0& -q_1& q_1\end{array}\right]$

$R=\frac{q_3}{{m_s}^2}N=\frac{q_3}{{m_s}^2}\left[\begin{array}{c}0\\ -k_s\\ 0\\ 0\\ 0\\ k_s\\ 0\end{array}\right]$

4) according to Riccati equation

AK+KA^T+Q-KBR^-1B^TK+FWF^T=0

Obtain gain matrix K=(k₁k₂k₃k₄k₅)；

5) according to gain matrix K and state variable X, the Optimal Control Force of linear electric motors output can be drawn：

$F_a=-KX=-(k_1{\stackrel{\·}{z}}_s+k_2{z}_s+k_3{\stackrel{\·}{z}}_t+k_4{z}_t+k_{5}q).$

6. the control method of the electromagnetic suspension system based on wheel rim driven motor vehicle according to claim 5, its feature exists According to the different mode suitable weight coefficient of selection；

When in comfortable sexual norm, then q₁=5.62, q₂=3283, q₃=21638；

When in safety profile, then q₁=1.03, q₂=50200, q₃=845000；

When in comprehensive sexual norm, then q₁=0.88, q₂=3000, q₃=38000.

7. the control method of the electromagnetic suspension system based on wheel rim driven motor vehicle according to claim 4, its feature exists According to the analysis of internal ring property in the PI algorithms, selected PI controller parameters are：Scale parameter P=1.55, integration ginseng Number I=0.7.