CN105337549A - Motor drive system - Google Patents

Abstract

The invention discloses a permanent magnet motor drive system which comprises an acquiring module, an SOC estimating module, a selecting module, an instruction calculating module, a bend compensation module, a rotor position detection module and a voltage vector modulating module. The acquiring module is used for acquiring a vehicle speed V, a motor rotor position theta r, a torque instruction value (please see the symbol in the specification) and bend information. The SOC estimating module is used for acquiring a current SOC estimating value S of a power battery. The selecting module is used for selecting an optimal efficiency driving mode to drive a motor. The instruction calculating module is used for calculating first axis-d current instruction values (please see the symbol in the specification) and first axis-q current instruction values (please see the symbol in the specification) of the motor through the optimal efficiency driving mode, a weak magnetism driving mode and a direct torque driving mode. By means of the permanent magnet motor drive system, the motor can adapt to different road conditions.

Description

Motor driven systems

Technical field

The invention belongs to machine field, particularly a kind of motor driven systems.

Background technology

Motor is the major impetus source of electric motor car, and current driving motor of electric vehicle generally adopts magneto (PMSM), and compared with electro-magnetic motor, it is simple that magneto, particularly rare-earth permanent-magnet electric machine have structure, reliable; Volume is little, and quality is light; Loss is little, and efficiency is high; The shape and size of motor versatile and flexiblely can wait remarkable advantage.At present in the type of drive of motor, all adopt single type of drive, it can not change type of drive according to road conditions, vehicle self-condition etc., such as straight road surface driver is wished to obtain the higher speed of a motor vehicle, and for the road surface of hollow, driver wishes to obtain larger torque, when battery electric quantity is too low, driver wishes again to adopt more energy-conservation type of drive, and to obtain maximum distance travelled, these requirements are irrealizable under single drive mode.

Summary of the invention

For the defect of prior art, the invention provides a kind of motor driven systems.

A kind of driving system of permanent magnet motor, comprising: acquisition module, for obtaining vehicle velocity V, motor rotor position θ _r, torque instruction value the three-phase electricity flow valuve ia of traffic information and input motor, ib, ic, described traffic information at least comprises straight road conditions, hollow road conditions and bend information; SOC estimation module, for obtaining voltage U s and the current i s signal of electrokinetic cell end, according to the Mathematical Modeling of set up electrokinetic cell, ampere-hour integration, state observer and adaptive extended kalman filtering method is adopted to estimate battery SOC respectively, estimated value is weighted, obtains the SOC estimated value S that electrokinetic cell is current; Select module, when being greater than the threshold value of setting for estimated value S, when selected road conditions are straight road conditions, selected weak Magnetic driving mode drive motors; When selected road conditions are hollow road conditions, selected Direct Torque type of drive drive motors; When judging that estimated value S is less than or equal to the threshold value of setting, selected efficiency optimal drive mode drive motors; Command calculations module, calculates motor d shaft current first command value for adopting efficiency optimal drive mode, weak Magnetic driving mode and Direct Torque type of drive respectively with q shaft current first command value bend compensating module, for calculating d shaft current offset according to described bend information with q shaft current offset according to described d shaft current first command value and current offset values calculate d shaft current second command value according to described q shaft current first command value and current offset values calculate q shaft current second command value rotor-position detection module, calculates motor rotor position θ for the three-phase electricity flow valuve ia according to input motor, ib, ic _r; Voltage vector modulation module, for according to described second command value second command value with motor rotor position θ _rpulse-width modulation is carried out to inverter.

Optionally, also comprise memory module, described memory module is connected with acquisition module, is pre-stored with the road information of many roads in described memory module, described acquisition module judges vehicle place road according to vehicle present position, reads the bend information of this road in described memory module.

Optionally, described bend information comprises the quantity of bend length, bend curvature and preset distance inner curve; Determine whether vehicle is positioned on bend or in the predetermined distance or the scheduled time that enter bend according to the bend information got and the current residing position of vehicle.

Optionally, described rotor-position detection module, calculates rotor position according to following formula _r:

θ _r(k+1)=3θ _r(k)-3θ _r(k-1)+θ _r(k-2)

In formula, K represents K state value.

Optionally, the Mathematical Modeling of described electrokinetic cell is:

$\begin{array}{c}{X}_k=\left[\begin{array}{cc}1& \frac{\mathrm{\η}\mathrm{\Δ}t}{C}\\ 0& 1\end{array}\right]X_{k-1}+\left[\begin{array}{c}\frac{-\mathrm{\η}\mathrm{\Δ}t}{C}\\ 0\end{array}\right]i_{m\left(k-1\right)}+\left[\begin{array}{c}{w}_{1\left(k-1\right)}\\ w_{2\left(k-1\right)}\end{array}\right]\\ ={\mathrm{\Φ}}_{k-1}{X}_{k-1}+{\mathrm{\Γ}}_{k-1}{i}_{m\left(k-1\right)}+w_{k-1}\end{array}$

$\begin{array}{c}{y}_k=g_1(X_k,i_{mk},v_k)\\ =E_0-R\left(i_{mk}-i_{sk}\right)-K_0{\mathrm{SOC}}_k-\frac{K_1}{{\mathrm{SOC}}_k}+K_2\ln \left({\mathrm{SOC}}_k\right)+K_3\ln (1-{\mathrm{SOC}}_k)+v_k\end{array}$

In formula, X _krepresent the state vector of battery pack, y _krepresent battery terminal voltage, η is the coulombic efficiency factor, and C is total capacity, E ₀for being full of the open circuit voltage under electricity condition, R is the internal resistance of cell, K ₀, K ₁, K ₂, K ₃for battery polarization internal resistance, △ t is the sampling period, i _mkfor current measurement value, i _skfor current sensor current drift estimated value, W ₁and W ₂, V _kfor separate white noise, SOC is battery electric quantity, and K represents K state value, K=0,1,2,3,4,5 ...

Optionally, described SOC estimation module, SOC value of battery is estimated respectively for adopting ampere-hour integration method, state observer method and adaptive extended kalman filtering method respectively, obtain SOC state estimation S1, S2, S3, then S1, S2, S3 are weighted, obtain final SOC estimated value S;

S＝ω ₁S ₁+ω ₂s ₂+ω ₃s ₃(3)

Wherein ω ₁, ω ₂, ω ₃for weight coefficient, ω ₁+ ω ₂+ ω ₃=1.

Optionally, also comprise timing module, described timing module and selection model calling, when judging that estimated value S is less than or equal to the threshold value of setting, timing module starts timing, after timing duration T is greater than the duration T0 of setting, selects module to select efficiency optimal drive mode drive motors.

Optionally, also comprise weak Magnetic driving module, described weak Magnetic driving module comprises function generator FG1 and FG2, the input of function generator FG1 with FG2 is connected with acquisition module, the output of function generator FG1 is connected with first adder, the output of first adder is connected with current regulator, and current regulator is connected with amplitude limiter by second adder, described amplitude limiter also function generator FG2 output be connected.

Optionally, also bag efficiency optimal drive module, described efficiency optimal drive module is calculated as follows d shaft current first command value with q shaft current first command value

$i_q^{*}=\frac{P_e}{E_O}=\frac{\sqrt{3}{P}_e}{{\mathrm{\ω}}_r{\mathrm{\ψ}}_f}$

$i_d^{*}=-\frac{L_s}{{\mathrm{\ψ}}_f}\frac{\sqrt{3}{P}_e}{\sqrt{R_s{R}_f}}$

In formula, Pe represents the electromagnetic power that motor often produces mutually, ω _rfor motor speed, ψ _frepresent iron core magnetic linkage, Ls represents stator inductance.

Optionally, described bend compensating module, is calculated as follows d shaft current second command value with q shaft current second command value

$\begin{array}{cccc}{\mathrm{\Δi}}_d^{*}=K_{sd}L+K_{sd}S;& {\mathrm{\Δi}}_q^{*}=K_{sq}L+K_{sq}S;& i_d^{**}=i_d^{*}+{\mathrm{\Δi}}_d^{*};& i_q^{**}=i_q^{*}+{\mathrm{\Δi}}_q^{*}\end{array}$

K in formula _sd, K _sd, K _sq, K _sq, be proportionality coefficient, L represents bend length, and S represents bend curvature, and namely bend departs from the angle of straight way.

The invention has the beneficial effects as follows: by accurate Mathematical Modeling, adopt multiple method to estimate SOC value, obtain SOC value more accurately, the manipulation for electric motor car provides foundation accurately; Adopt sensorless technology detection rotor position, reduce cost; Consider pavement behavior and battery information, adjusted the type of drive of vehicle according to different pavement behavior in real time, make Vehicle handling being improved; Consider bend and motor is driven to the impact brought, after running into bend, adjust motor energization current and torque current, thus ensure that the stability of vehicle in turning process.

Accompanying drawing explanation

Fig. 1 is the structure chart of motor driven systems of the present invention;

Fig. 2 is weak Magnetic driving block diagram;

Fig. 3 is PMSM equivalent circuit diagram.

Embodiment

For enabling above-mentioned purpose of the present invention, feature and advantage become apparent more, are described in detail the specific embodiment of the present invention below in conjunction with accompanying drawing, make above-mentioned and other object of the present invention, Characteristics and advantages will be more clear.Reference numeral identical in whole accompanying drawing indicates identical part.Deliberately do not draw accompanying drawing in proportion, focus on purport of the present invention is shown.

Refer to Fig. 1, vehicle can better be driven to make motor, make vehicle can provide better manipulation/feeling for taking to driver under different road conditions, first the present invention determines the drive pattern of vehicle according to the electricity (SOC) of electrokinetic cell, when selected road conditions are straight road conditions, selected weak Magnetic driving mode drive motors; When selected road conditions are hollow road conditions, selected Direct Torque type of drive drive motors; When judging that estimated value S is less than or equal to the threshold value of setting, selected efficiency optimal drive mode drive motors, according to the type of drive of bend information adjustment vehicle PMSM motor, thus improves handling, the comfortableness taken of vehicle.

Acquisition module, for obtaining vehicle velocity V, motor rotor position θ _r, torque instruction value the three-phase electricity flow valuve ia of traffic information and input motor, ib, ic, described traffic information at least comprises straight road conditions, hollow road conditions and bend information.

Specifically, current sensor can be adopted to measure three-phase current ia, ib, ic of inverter output respectively, and the detection of vehicle velocity V has various ways, can carry out calculating torque command value according to the depression amount of gas pedal the acquisition of these information above-mentioned is prior art, repeats no more.

For some road conditions as wet and slippery road conditions, straight road conditions, hollow road conditions etc., driver can be easy to recognize by observation, just corresponding traffic information can be sent to vehicle control system by selection key, these buttons can comprise wet and slippery, hollow, straight, accumulated snow etc., in the present invention, straight road conditions refer to and do not have bend in certain distances, and road surface is without fluctuating, evenness of road surface, such as, in 2KM, this road conditions are suitable for high vehicle speeds.Hollow road conditions refer to road surface and there is many places projection and depression, pavement roughness, and this road conditions should not be run at high speed, and it requires that vehicle exports larger torque to overcome projection and the depression on road surface.Cannot obtain by observing for bend information driver, bend information can comprise the quantity of bend length, bend curvature and preset distance inner curve, such as, in the quantity of the inner curve of 2 kms.Bend length, curvature and quantity and motor drive mode closely bound up, it affects the handling of vehicle and the comfort taken.Such as larger curvature then needs the low speed of a motor vehicle and high moment of torsion.

For this reason, the present invention is provided with memory module, the traffic information of its pre-stored many roads, and acquisition module judges vehicle place road according to vehicle present position, reads the information of this road from the traffic information of pre-stored.Position residing for vehicle can be provided by such as global positioning system (GPS).The position on this road residing for bend, length, curvature and quantity is contained in the traffic information of pre-stored.

Motor rotor position θ _rcan by detections such as detecting element such as encoders, but detecting element price is higher, and for electric motor car, being installed on by detecting element in drive system needs to take larger space, installs inconvenience.The present invention adopts sensorless detection method to detect motor rotor position θ for this reason _r.The mechanical equation of PMSM is:

$T_e=J\frac{{\mathrm{d\Ω}}_r}{dt}+R_{\mathrm{\Ω}}{\mathrm{\Ω}}_r+T_1---\left(1\right)$

Due to θ _r=∫ ω _rdt, therefore formula (1) can be rewritten as:

$T_e=\frac{J}{p_n}\·\frac{d^2{\mathrm{\θ}}_r}{dt}+\frac{R_{\mathrm{\Ω}}}{p_n}\·\frac{{\mathrm{d\θ}}_r}{dt}+T_1---\left(2\right)$

In formula, Te is electromagnetic torque, and Pn is number of pole-pairs, R _Ωfor damping coefficient, J is moment of inertia, T ₁for load torque.Formula (2) shows rotor position _raccording to the change of quadratic polynomial rule, that is:

θ _r(t)=At ²+Bt+C(3)

In formula, A, B, C are the coefficient of quadratic polynomial, if the sampling period is T, K represent K state value, from formula (3), rotor position next time can be obtained from first three rotor position estimate value, suppose the initial time t=0 estimated for the K-2 time, then:

θ _r(k-2)＝C(4)

At the initial time that the K-1 time is estimated, rotor-position is:

θ _r(k-1)＝AT ²+BT+C(5)

In like manner, K time: θ _r(k)=A (2T) ²+ B (2T) ²+ C (6)

So, at the initial time that K+1 time is estimated, θ _rp(k+1)=A (3T) ²+ B (3T) ²+ C (7);

The value of A, B, C can be obtained by formula 4 ~ 6, after substituting into formula 7, can obtain:

θ _r(k+1)＝3θ _r(k)-3θ _r(k-1)+θ _r(k-2)(8)

Just motor rotor position θ can be obtained thus _r.

SOC estimation module, for obtaining voltage U s and the current i s signal of electrokinetic cell end, according to the Mathematical Modeling of set up electrokinetic cell, ampere-hour integration, state observer and adaptive extended kalman filtering method is adopted to estimate battery SOC respectively, estimated value is weighted, obtains the SOC estimated value S that electrokinetic cell is current.

Can adopt current sensor, voltage sensor measures terminal voltage Us and the output current is of power battery pack respectively.The Mathematical Modeling of electrokinetic cell has multiple at present, such as desirable equivalent model, desirable equivalent model regards fixed value as the internal resistance of battery, do not consider the difference of internal resistance of cell when battery charging, electric discharge, therefore also just can embody charging, the difference of SOC when discharging, this model and actual value gap larger; Thevenin model, the defect of Thevenin model is that in circuit, parameter is all definite value, and they are the functions of SOC in fact; RC model, RC model can better the dynamic characteristic of simulated battery than Thevenin model, but have ignored the temperature effect of battery, considers abundant not to polarity effect; EMF model is compared with Thevenin model with RC model, except the dynamic characteristic of more consideration batteries, also considers the impact of the factors such as chemical polarization concentration polarization preferably, but also have ignored temperature effect.The present invention adopts built-up pattern for this reason, and its discrete state space equation is:

$\begin{array}{c}{X}_k=\left[\begin{array}{cc}1& \frac{\mathrm{\η}\mathrm{\Δ}t}{C}\\ 0& 1\end{array}\right]X_{k-1}+\left[\begin{array}{c}\frac{-\mathrm{\η}\mathrm{\Δ}t}{C}\\ 0\end{array}\right]i_{m\left(k-1\right)}+\left[\begin{array}{c}{w}_{1\left(k-1\right)}\\ w_{2\left(k-1\right)}\end{array}\right]\\ ={\mathrm{\Φ}}_{k-1}{X}_{k-1}+{\mathrm{\Γ}}_{k-1}{i}_{m\left(k-1\right)}+w_{k-1}\end{array}---\left(9\right)$

$\begin{array}{c}{y}_k=g_1(X_k,i_{mk},v_k)\\ =E_0-R\left(i_{mk}-i_{sk}\right)-K_0{\mathrm{SOC}}_k-\frac{K_1}{{\mathrm{SOC}}_k}+K_2\ln \left({\mathrm{SOC}}_k\right)+K_3\ln (1-{\mathrm{SOC}}_k)+v_k\end{array}---\left(10\right)$

In formula, Xk represents the state vector of battery pack, and yk represents battery terminal voltage, η is the coulombic efficiency factor, and C is total capacity, and E0 is the open circuit voltage be full of under electricity condition, R is the internal resistance of cell, and K0, K1, K2, K3 are battery polarization internal resistance, and △ t is the sampling period, imk is current measurement value, isk is current sensor current drift estimated value, W1 and W2, Vk are separate white noise, and SOC is battery electric quantity, K represents K state value, K=0,1,2,3,4,5 ...

Then according to the Mathematical Modeling of battery pack, ampere-hour integration method, state observer method and adaptive extended kalman filtering method is adopted to estimate SOC value of battery respectively respectively, obtain SOC state estimation S1, S2, S3, then S1, S2, S3 are weighted, obtain final SOC estimated value S.

S＝ω ₁S ₁+ω ₂s ₂+ω ₃s ₃(11)

Wherein ω ₁, ω ₂, ω ₃for weight coefficient, ω ₁+ ω ₂+ ω ₃=1.Adopt multiple method to estimate the state-of-charge SOC of electrokinetic cell respectively, well draws final estimated value to estimated result row weighted calculation of spouting, and improves the estimated accuracy of the SOC of electrokinetic cell.

Select module, when being greater than the threshold value of setting for estimated value S, when selected road conditions are straight road conditions, selected weak Magnetic driving mode drive motors; When selected road conditions are hollow road conditions, selected Direct Torque type of drive drive motors; When judging that estimated value S is less than or equal to the threshold value of setting, selected efficiency optimal drive mode drive motors.

For electric motor car, the handling comfortableness with taking of its vehicle depends primarily on the driving of motor.In order to better handling and comfortableness can be reached, need the type of drive adjusting motor according to road conditions in real time, the type of drive of motor can comprise weak Magnetic driving, Direct Torque driving etc., these type of drive can adapt to different road conditions requirements, substantially increase handling, this drive pattern adjusting the type of drive of motor according to road conditions in real time can be called as intelligent drives pattern.But under intelligent drives pattern, the operational efficiency of motor is not best, when battery electric quantity SOC is too low, if still adopt intelligent drives pattern, then the operating range of vehicle will shorten greatly, in order to can when battery electric quantity SOC be too low, electrokinetic cell is made to meet the normal needs travelled, only have when judging that estimated value S is greater than the threshold value of setting in the present invention, just enter intelligent drives pattern, this threshold value can be 30% of the total electricity of power battery, namely when estimated value S is greater than 30% of the total electricity of battery, vehicle is then allowed to enter intelligent drives pattern, when estimated value S is less than or equal to 30% then, enter efficiency optimal drive pattern.Such as when battery electric quantity remains 50%, vehicle enters intelligent driving pattern, its road conditions selected from input module acquisition driver, if selected road conditions are straight road conditions, then select the weak Magnetic driving mode of model choice, when the road conditions that driver selectes are hollow road conditions, select model choice Direct Torque drive pattern drive motors to run, along with the continuous operation of motor, battery electric quantity declines, when battery electric quantity drops to 30%, select model choice efficiency optimal drive mode drive motors.

Further, because electrokinetic cell exists the phenomenon of " power down ", namely when moment obtains larger electric power from electrokinetic cell, now estimated value S can be less than its actual electricity, such as, when the actual electricity of vehicle remains 35%, now improves the actuating force of vehicle instantaneously, then estimated value S can about 25%, and when again recovering driven, estimated value S can rise to 35%, this just causes the abnormal of intelligent driving pattern and exits.To this, in order to judge now whether vehicle should enter/exit intelligent driving pattern, the present invention arranges a timing module, when judging that estimated value S is less than or equal to the threshold value of setting, timing module starts timing, after timing duration T is greater than the duration T0 of setting, if now estimated value S is still less than or equal to the threshold value of setting, then exit intelligent driving pattern.The setting of duration T0, between showing at this moment, in section, the electricity of battery is in lasting minimizing, and this minimizing is not caused by " power down ", and it is more accurate so just to make to judge.

Command calculations module, calculates motor d shaft current first command value for adopting efficiency optimal drive mode, weak Magnetic driving mode and Direct Torque type of drive respectively with q shaft current first command value

Weak magnetics detect is a study hotspot of current PMSM, motor weakens magnetic field just can realize high-speed cruising (torque also reduces thereupon), speed adjustable range is broadened, and contribute to electric automobile and obtain the higher speed of a motor vehicle, this is very favourable when straight road traveling.As shown in Figure 2, actual current id and iq is according to the threephase stator electric current that detects and rotor position to weak Magnetic driving module _robtain through vector, the first command value with q shaft current first command value be by FG1 and FG2 according to calculate, add current regulator and q shaft current amplitude limiter in weak Magnetic driving module of the present invention, deviation delta i _dfor current regulator input, export as i _dc, the input of current limiter is the output of FG2, amplitude limit value i _q1=i _qmax-i _dc, i _qmaxfor set-point.When inverter current regulator saturation, i _dcincrease, reduce q shaft current command value by amplitude limiter, i ₀and i _qmaxfor set-point, its given foundation is for ensureing that weak magnetics detect and normal current do not affect between controlling.

Direct torque control is that torque is directly controlled as controlled volume, its essence is the analytical method with space vector, in stator flux orientation mode, carries out directly actuated to stator magnetic linkage and electromagnetic torque.This method does not need complicated coordinate transform, but directly on motor stator coordinate, calculates the mould of magnetic linkage and the size of torque, and realizes the high dynamic performance of PWM pulse-width modulation and system by the direct tracking of magnetic linkage and torque.Direct torque control has strong robustness, torque rapid dynamic response speed, is applicable to for the higher potted road surface of direct torque requirement.Current existing multiple Study on direct torque control technology, does not repeat them here.

When estimated value S is less than or equal to the threshold value of setting, adopt efficiency optimal drive mode.The loss of magneto is mainly derived from stator copper loss and core loss, and Fig. 3 is the equivalent electric circuit of the PMSM considering core loss, R in figure _frepresent iron core equivalent resistance, Rs represents stator resistance, E ₀represent back electromotive force, Ux is the voltage corresponding with stator magnetic linkage, and this magnetic linkage produces eddy current and magnetic hysteresis loss in iron core.The every phase loss of PMSM motor can be expressed as:

$P_W=\frac{1}{R_f}{U}_x^2+R_s{i}_s^2---\left(12\right)$

Getting q axle is real axis, and d axle is the imaginary axis in the other direction, then have:

U _x＝U _xq-jU _xd

I _e＝I _q-jI _d(13)

And in formula, Pe represents the electromagnetic power that motor often produces mutually, ω _rfor motor speed, ψ _frepresent iron core magnetic linkage.

In Fig. 3, Ux can be expressed as: U _x=(E ₀+ I _dω _rl _s)+j (I _qω _rl _s) (15), utilize formula 13-15, to formula 12 minimizing, can obtain:

$I_d^{*}=-\frac{L_s}{{\mathrm{\ψ}}_f}\frac{\sqrt{3}{P}_e}{\sqrt{R_s{R}_f}}---\left(16\right);$

This point is the highest point of motor operational efficiency, can be regulated the proportionate relationship of iron loss and copper loss, make motor iron loss equal with copper loss by control frequency and demagnetizing current, thus reaches best operational efficiency.When this is too low for battery electric quantity SOC, it is favourable for increasing Vehicle-Miles of Travel.

Bend compensating module, for calculating d shaft current offset according to described bend information with q shaft current offset according to described d shaft current first command value and current offset values calculate d shaft current second command value according to described q shaft current first command value and current offset values calculate q shaft current second command value

Bend information can comprise the quantity of bend length, bend curvature and preset distance inner curve, such as, in the quantity of the inner curve of 2 kms.The driving of bend length, curvature and quantity and vehicle is closely bound up, and it affects the handling of vehicle and fail safe.Such as larger curvature then needs larger torque and the lower speed of a motor vehicle.The present invention carrys out calculating current offset in proportion according to bend length L and bend curvature S for this reason and current offset values that is:

${\mathrm{\Δi}}_d^{*}=K_{sd}L+K_{sd}S---\left(17\right)$

${\mathrm{\Δi}}_q^{*}=K_{sq}L+K_{sq}S---\left(18\right);$

K in formula _sd, K _sd, K _sq, K _sq, be proportionality coefficient, can experimentally determine, the minimum principle determined ensures that vehicle does not topple crossing in curved process.

$i_d^{**}=i_d^{*}+{\mathrm{\Δi}}_d^{*}---\left(19\right)$

$i_q^{**}=i_q^{*}+{\mathrm{\Δi}}_q^{*}---\left(20\right)$

Further, when the quantity of preset distance inner curve is greater than set point, if now the speed of a motor vehicle is too high, easily cause danger, to this present invention when the quantity of preset distance inner curve is greater than set point, obtain the speed of a motor vehicle of vehicle, when the speed of a motor vehicle is greater than setting threshold, such as 80KM/h, now send alarm to driver, remind driver's slow down.

Voltage vector modulation module, for according to described second command value second command value with motor rotor position θ _rpulse-width modulation is carried out to inverter.After obtaining the second command value, vehicle ECU calculates each phase trigger impulse of inverter to inverter, drives IGBT in inverter, thus export corresponding electric current by drive circuit, drives PMSM to run.

Set forth a lot of detail in the above description so that fully understand the present invention.But above description is only preferred embodiment of the present invention, the present invention can be much different from alternate manner described here to implement, and therefore the present invention is not by the disclosed concrete restriction implemented above.Any those skilled in the art are not departing under technical solution of the present invention ambit simultaneously, the Method and Technology content of above-mentioned announcement all can be utilized to make many possible variations and modification to technical solution of the present invention, or be revised as the Equivalent embodiments of equivalent variations.Every content not departing from technical solution of the present invention, according to technical spirit of the present invention to any simple modification made for any of the above embodiments, equivalent variations and modification, all still belongs in the scope of technical solution of the present invention protection.

Claims (10)

1. a driving system of permanent magnet motor, is characterized in that, comprising:

Acquisition module, for obtaining vehicle velocity V, motor rotor position θ _r, torque instruction value the three-phase electricity flow valuve ia of traffic information and input motor, ib, ic, described traffic information at least comprises straight road conditions, hollow road conditions and bend information;

SOC estimation module, for obtaining voltage U s and the current i s signal of electrokinetic cell end, according to the Mathematical Modeling of set up electrokinetic cell, ampere-hour integration, state observer and adaptive extended kalman filtering method is adopted to estimate battery SOC respectively, estimated value is weighted, obtains the SOC estimated value S that electrokinetic cell is current;

Select module, when being greater than the threshold value of setting for estimated value S, when selected road conditions are straight road conditions, selected weak Magnetic driving mode drive motors; When selected road conditions are hollow road conditions, selected Direct Torque type of drive drive motors; When judging that estimated value S is less than or equal to the threshold value of setting, selected efficiency optimal drive mode drive motors;

Command calculations module, calculates motor d shaft current first command value for adopting efficiency optimal drive mode, weak Magnetic driving mode and Direct Torque type of drive respectively with q shaft current first command value

Bend compensating module, for calculating d shaft current offset according to described bend information with q shaft current offset according to described d shaft current first command value and current offset values calculate d shaft current second command value according to described q shaft current first command value and current offset values calculate q shaft current second command value

Rotor-position detection module, calculates motor rotor position θ for the three-phase electricity flow valuve ia according to input motor, ib, ic _r;

Voltage vector modulation module, for according to described second command value second command value with motor rotor position θ _rpulse-width modulation is carried out to inverter.

2. driving system of permanent magnet motor according to claim 1, it is characterized in that, also comprise memory module, described memory module is connected with acquisition module, the road information of many roads is pre-stored with in described memory module, described acquisition module judges vehicle place road according to vehicle present position, reads the bend information of this road in described memory module.

3. driving system of permanent magnet motor according to claim 1, is characterized in that, described bend information comprises the quantity of bend length, bend curvature and preset distance inner curve; Determine whether vehicle is positioned on bend or in the predetermined distance or the scheduled time that enter bend according to the bend information got and the current residing position of vehicle.

4. driving system of permanent magnet motor according to claim 1, is characterized in that, described rotor-position detection module, calculates rotor position according to following formula _r:

θ _r(k+1)＝3θ _r(k)-3θ _r(k-1)+θ _r(k-2)

In formula, K represents K state value.

5. driving system of permanent magnet motor according to claim 1, is characterized in that, the Mathematical Modeling of described electrokinetic cell is:

$\begin{array}{c}{X}_k=\left[\begin{array}{cc}1& \frac{\mathrm{\η}\mathrm{\Δ}t}{C}\\ 0& 1\end{array}\right]X_{k-1}+\left[\begin{array}{c}\frac{-\mathrm{\η}\mathrm{\Δ}t}{C}\\ 0\end{array}\right]i_{m\left(k-1\right)}+\left[\begin{array}{c}{w}_{1\left(k-1\right)}\\ w_{2\left(k-1\right)}\end{array}\right]\\ ={\mathrm{\Φ}}_{k-1}{X}_{k-1}+{\mathrm{\Γ}}_{k-1}{i}_{m\left(k-1\right)}+w_{k-1}\end{array}$

$\begin{array}{c}{y}_k=g_1\left(X_k,i_{mk},v_k\right)\\ =E_0-R\left(i_{mk}-i_{sk}\right)-K_0{\mathrm{SOC}}_k-\frac{K_1}{{\mathrm{SOC}}_k}+K_2\ln \left({\mathrm{SOC}}_k\right)+K_3\ln \left(1-{\mathrm{SOC}}_k\right)+v_k\end{array}$

In formula, X _krepresent the state vector of battery pack, y _krepresent battery terminal voltage, η is the coulombic efficiency factor, and C is total capacity, E ₀for being full of the open circuit voltage under electricity condition, R is the internal resistance of cell, K ₀, K ₁, K ₂, K ₃for battery polarization internal resistance, △ t is the sampling period, i _mkfor current measurement value, i _skfor current sensor current drift estimated value, W ₁and W ₂, V _kfor separate white noise, SOC is battery electric quantity, and K represents K state value, K=0,1,2,3,4,5 ...

6. driving system of permanent magnet motor according to claim 1, it is characterized in that, described SOC estimation module, SOC value of battery is estimated respectively for adopting ampere-hour integration method, state observer method and adaptive extended kalman filtering method respectively, obtain SOC state estimation S1, S2, S3, then S1, S2, S3 are weighted, obtain final SOC estimated value S;

S＝ω ₁S ₁+ω ₂s ₂+ω ₃s ₃(3)

Wherein ω ₁, ω ₂, ω ₃for weight coefficient, ω ₁+ ω ₂+ ω ₃=1.

7. driving system of permanent magnet motor according to claim 1, it is characterized in that, also comprise timing module, described timing module and selection model calling, when judging that estimated value S is less than or equal to the threshold value of setting, timing module starts timing, after timing duration T is greater than the duration T0 of setting, selects module to select efficiency optimal drive mode drive motors.

8. driving system of permanent magnet motor according to claim 1, it is characterized in that, also comprise weak Magnetic driving module, described weak Magnetic driving module comprises function generator FG1 and FG2, the input of function generator FG1 with FG2 is connected with acquisition module, and the output of function generator FG1 is connected with first adder, and the output of first adder is connected with current regulator, current regulator is connected with amplitude limiter by second adder, described amplitude limiter also function generator FG2 output be connected.

9. driving system of permanent magnet motor according to claim 1, is characterized in that, also bag efficiency optimal drive module, and described efficiency optimal drive module is calculated as follows d shaft current first command value with q shaft current first command value

$i_q^{*}=\frac{P_e}{E_0}=\frac{\sqrt{3}{P}_e}{{\mathrm{\ω}}_r{\mathrm{\ψ}}_f}$

$i_d^{*}=-\frac{L_s}{{\mathrm{\ψ}}_f}\frac{\sqrt{3}{P}_e}{\sqrt{R_s{R}_f}}$

In formula, Pe represents the electromagnetic power that motor often produces mutually, ω _rfor motor speed, ψ _frepresent iron core magnetic linkage, Ls represents stator inductance.

10. driving system of permanent magnet motor according to claim 1, is characterized in that, described bend compensating module, is calculated as follows d shaft current second command value with q shaft current second command value

${\mathrm{\Δi}}_d^{*}=K_{sd}L+K_{sd}S;{\mathrm{\Δi}}_q^{*}=K_{sq}L+K_{sq}S;i_d^{**}=i_d^{*}+{\mathrm{\Δi}}_d^{*};i_q^{**}=i_q^{*}+{\mathrm{\Δi}}_q^{*}$

K in formula _sd, K _sd, K _sq, K _sq, be proportionality coefficient, L represents bend length, and S represents bend curvature, and namely bend departs from the angle of straight way.