CN102167036B - Control method of fuel cell hybrid vehicle - Google Patents

Abstract

The invention relates to a control method of a fuel cell hybrid vehicle, which comprises the following steps: a vehicle controller is internally provided with a motor status switching module, a driver order explaining module, a power cell charged status verifying module, a road condition self-adaption compensating module, a vehicle diagnosis correcting module and an equivalent hydrogen consumption optimal distributing module; the vehicle controller reads a gear signal, a pedal signal and TTCAN (triggered controller area network) bus data; the motor status switching module switches the motor status; the driver order explaining module confirms a motor target torque; the power cell charged status verifying module verifies a SOC (system on chip) value, TTCAN bus voltage and power cell current; the road condition self-adaption compensating module computes the auxiliary power and the DC (direct current) /DC dynamic compensation time constant of the vehicle; the vehicle diagnosis correcting module corrects the motor target torque and the DC/DC target current; the equivalent hydrogen consumption optimal distributing module optimally distributes the vehicle target power between the power cell and the fuel cell; and the modified motor target torque and the DC/DC target current are transmitted to a motor controller and a DC/DC controller so as to control the output power of the motor and the fuel cell.

Description

A kind of fuel cell hybrid control method of finished

Technical field

The present invention relates to a kind of control method for vehicle, particularly about a kind of fuel cell hybrid control method of finished towards general city operating mode.

Background technology

Oil resources scarcity and environmental pollution are the significant problems that countries nowadays government, scientific research institution and transnational enterprise pay close attention to, and many national government and enterprise drop into the technical scheme that a large amount of The Study on Resources address this problem.Fuel cell (or being called Proton Exchange Membrane Fuel Cells) relies on the chemical reaction of hydrogen and oxygen to produce electric current, and generates water, and noise is low and pollution-free, therefore is considered to solve the important technology scheme of resource and environmental problem.

Current fuel cell mainly is to be applied to fuel cell hybrid car.Fuel cell hybrid car generally adopts fuel cell to add the configuration of electrokinetic cell or super capacitor.Electrokinetic cell (or super capacitor) provides overload power when loading, avoid the sudden change of fuel cell operating mode; During braking, electrokinetic cell (or super capacitor) absorption portion braking energy improves system economy.The fuel cell hybrid system comprises a plurality of propulsions source (for example fuel cell motive force source and electrokinetic cell propulsion source), carries out work by these a plurality of propulsions source of vehicle control unit controls.

Aspect the hybrid power configuration of fuel cell hybrid car, prior art provides a kind of " energy type " hybrid power system.(fine line represents that high pressure connects among the figure as shown in Figure 1, heavy line is represented mechanical connection), in this configuration, fuel cell system is by DC to DC converter (Direct Current to Direct Current converter, DC/DC) in parallel with electrokinetic cell, then (Direct Current to Alternating Current inverter DC/AC) changes alternating current into and drives threephase asynchronous machine by DC/AC inverter.The control method of finished of pluralities of fuel cell hybrid power automobile also is provided in the prior art, comprise rule-based control method of finished, instantaneous optimization, global optimization and braking energy feedback control method of finished etc., but do not provide towards the control method of finished of general city operating mode.

Summary of the invention

At the problems referred to above, the energy that the purpose of this invention is to provide that a kind of mea velocity is low, acceleration and deceleration operating mode proportion height, braking consumes is big, can solve the fuel cell hybrid control method of finished of city operating mode.

For achieving the above object, the present invention takes following technical scheme: a kind of fuel cell hybrid control method of finished, may further comprise the steps: 1) motor status handover module, driver's command interpretation module, power battery charged state verification module, road conditions adaptive equalization module, car load diagnosis correcting module and equivalent hydrogen consumption are set in entire car controller optimize distribution module, wherein, TTCAN is time trigger-type controller local area network; 2) described entire car controller reads in driver's shift signal, driver's pedal signal and TTCAN bus communication data from digital quantity, analog quantity and TTCAN PORT COM; 3) described motor status handover module switches motor status according to driver's shift signal and driver's pedal signal between " driving, idling, slide, brake, move backward "; 4) described driver's command interpretation module is determined motor status according to the motor status signal that the motor status handover module arranges, and then definite motor target torque; 5) described power battery charged state verification module SOC value that power battery management system is sent, and TTCAN bus voltage, electrokinetic cell electric current carry out verification, and wherein, the SOC value is the power battery charged state proof test value; 6) described road conditions adaptive equalization module is according to the unit information that receives, at line computation car load auxiliary power P _Aux, DC/DC dynamic compensation timeconstant _Dc, and to electrokinetic cell SOC value, fuel battery performance decline compensates and the self adaptation adjustment; 7) described car load diagnosis correcting module is revised motor target torque and DC/DC target current according to the restriction of the operating range of each parts; 8) described equivalent hydrogen consumption is optimized in the distribution module, and the car load target power is optimized distribution between electrokinetic cell and fuel cell, makes system's equivalence hydrogen consumption minimum, and keeps SOC value balance; 9) entire car controller sends to electric machine controller and DC/DC controller with revised motor target torque and DC/DC target current respectively by the TTCAN bus, realizes the horsepower output control to motor and fuel cell.

In the described step 3), the switch step of described motor status handover module is as follows: judge 1. whether driver's shift signal is neutral, if it is idling that motor status then is set, otherwise enters next step; 2. judge whether shift signal is backward gear, if motor status then is set is reversing; Otherwise enter next step; 3. whether judge brake pedal greater than the braking threshold value, if motor status then is set is braking; Otherwise enter next step; 4. judge brake pedal whether smaller or equal to the braking threshold value, and acceleration pedal is greater than accelerating threshold value, if, motor status then is set for driving, otherwise, motor status is set for sliding.

In the described step 4), described driver's command interpretation module is determined motor in idling, reversing, driving and sliding state following time, and then the motor target torque is for driving target torque

α is driver's pedal position signal in the following formula, span 0～1; T _{Qd, max}Be the motor maximum driving torque, according to full-throttle characteristics and the target torque graph of a relation of motor under driving condition, obtain driving target torque

Value; Described driver's command interpretation module is determined motor in braking mode following time, and then the motor target torque is the braking target torque

γ is the brake pedal coefficient in the following formula, T _{Qb, max}Be maximum braking torque, according to full-throttle characteristics and the target torque graph of a relation of motor under braking mode, obtain braking target torque

Value.

Described brake pedal coefficient gamma, when adopting tandem braking energy feedback strategy, described brake pedal coefficient gamma obtains by following formula: γ=4 (β-β ₁) (β-β ₂) (β ₁-β ₂) ^-2, β is brake pedal position signal in the following formula, β ₁And β ₂Be the feedback braking policing parameter, this parameter influence car brakeing effect, demarcation obtains according to actual conditions.

In the described step 5), the checking procedure of described power battery charged state verification module is as follows: 1. uses the current electrokinetic cell open circuit voltage of the online estimation of least square recursive algorithm and on average discharges and recharges internal resistance, and in conjunction with electrokinetic cell open circuit voltage-SOC curve with discharge and recharge the anti-SOC of the pushing away value of internal resistance-SOC curve; 2. the SOC value that sends according to power battery management system, in conjunction with electrokinetic cell open circuit voltage-SOC curve with discharge and recharge internal resistance-SOC curve, extrapolate the electrokinetic cell open circuit voltage and on average discharge and recharge internal resistance; 3. calculate the open circuit voltage obtain in 2., on average discharge and recharge the SOC value that internal resistance and power battery management system send according to step, calculate with respect to step and estimate the open circuit voltage that obtains in 1., on average discharge and recharge the relative error of internal resistance and SOC value; If 4. the relative error of three kinds of parameter values is all less than 10%, then power battery charged state verification module judges that the SOC value that power battery management system sends is credible, otherwise the SOC estimated value that power battery charged state verification module adopts step to obtain in 1. replaces the SOC value of power battery management system transmission.

In the described step 6), in described road conditions adaptive equalization module, described car load auxiliary power P _AuxAccording to the TTCAN bus data, adopt single order LPF algorithm to carry out online estimation:

$P_{\mathrm{aux}}=\frac{P_{\mathrm{dc}}+P_{\mathrm{bat}}-P_{m,\mathrm{in}}}{{\mathrm{\τ}}_{\mathrm{aux}}s+1},$

P in the following formula _DcBe DC/DC horsepower output, P _BatBe electrokinetic cell horsepower output, P _{M, in}Be power input to machine, all can read τ from the TTCAN bus data _AuxBe filter constant, s is the plural variable of transfer function; Described DC/DC dynamic compensation timeconstant _DcBe calculated as follows: τ _Dc=λ ₁Δ τ _Dc1+ λ ₂Δ τ _Dc2+ λ ₃Δ τ _Dc3+ τ _Dc0, λ in the following formula ₁, λ ₂, λ ₃Be fuel battery performance decline coefficient of weight: λ ₁=0.4, λ ₂=0.4, λ ₃=0.2, τ _Dc0=5s, Δ τ _Dc1, Δ τ _Dc2With Δ τ _Dc3Be respectively the U-I of fuel cell system curve three parameter open circuit voltage U ₀, ohmic internal resistance R _FcWith the correction that the concentration polarization parameter b is determined, Δ τ _Dc1, Δ τ _Dc2With Δ τ _Dc3Change with the fuel cell pile performance degradation.

In the described step 9), the computing formula of revised described motor target torque and DC/DC target current is as follows:

$\left\{\begin{array}{c}{I}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}}^{*}=I_{\mathrm{dc}}^{*}-{\mathrm{\ΔI}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}1}^{*}-{\mathrm{\ΔI}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}2}^{*}\\ T_{q,\mathrm{mod}\mathrm{ified}}^{*}=T_q^{*}-{\mathrm{\ΔT}}_{q,\mathrm{mod}\mathrm{ified}}^{*}\end{array}\right.,$

In the following formula

Be the motor target torque,

Be motor target torque diagnosis correction,

Be the DC/DC target current of unmodified,

Be the DC/DC target current correction of consideration electrokinetic cell SOC value balance,

Be DC/DC target current diagnosis correction,

Be drive motor target torque diagnosis correction.

The present invention is owing to take above technical scheme, and it has the following advantages: 1, the present invention has considered system economy, fuel cell durability and car load safety, solves the energy management problem of city operating mode.2, the invention provides a kind of fuel cell hybrid passenger vehicle complex energy management process, entire car controller is according to driver's shift signal, driver's pedal signal and the time trigger-type controller local area network TTCAN bus communication data of input, determine motor target torque and DC/DC target current, with motor target torque and DC/DC target current to the TTCAN bus.3, the present invention can realize system economy optimization under the operating mode of city, guarantees electrokinetic cell SOC balance, prolongs fuel cell service life as far as possible, ensures car load safety.Use fuel battery city carriage of the present invention successfully to carry out the demonstration of Olympic Games demonstration and Beijing Public Transport and run, reach internal class, international advanced level, therefore can be widely used in the fuel cell hybrid car control application.

Description of drawings

Fig. 1 is control scheme drawing of the prior art

Fig. 2 is that entire car controller of the present invention is formed scheme drawing

Fig. 3 is entire car controller workflow diagram of the present invention

Fig. 4 is motor status handover module workflow diagram of the present invention

Fig. 5 is motor status handoff relation scheme drawing of the present invention

Fig. 6 is driver's command interpretation module workflow diagram of the present invention

Fig. 7 is full-throttle characteristics and the motor braking target torque graph of a relation of motor of the present invention under driving condition

Fig. 8 is full-throttle characteristics and the target torque graph of a relation of motor of the present invention under braking mode

Fig. 9 is SOC verification module workflow diagram of the present invention

Figure 10 is road conditions adaptive equalization module workflow diagram of the present invention

Figure 11 is dynamic compensation time constant Δ τ of the present invention _DcGraph of a relation with three parameters

Figure 12 is car load diagnosis correcting module workflow diagram of the present invention

Figure 13 is car load diagnosis correction algorithm block diagram of the present invention

Figure 14 is that the present invention's equivalence hydrogen consumption is optimized the distribution module workflow diagram

Figure 15 is the present invention when working as electrokinetic cell SOC balance coefficient of correction μ=0.6, the graph of a relation of electrokinetic cell optimal power and SOC

The specific embodiment

Below in conjunction with drawings and Examples the present invention is described in detail.

As Fig. 2, shown in Figure 3, comprise motor status handover module, driver's command interpretation module, SOC(State of Charge in the entire car controller of the present invention, power battery charged state) verification module, road conditions adaptive equalization module, car load diagnosis correcting module and equivalent hydrogen consumption are optimized distribution module, also possess interfaces such as digital quantity port, analog quantity port and TTCAN PORT COM.Signals such as SOC, bus voltage, electrokinetic cell electric current in the diagram, by (the Battery Management System of the BMS in the existing installation, power battery management system) after measuring, calculating, send to TTCAN(Time Triggered Controller Area Network, time trigger-type controller local area network) on the bus; Motor speed signal is measured, is calculated by the electric machine controller in the existing installation, sends on the TTCAN bus; Unit information sends on the TTCAN bus after being measured, calculated by each Parts Controller (electric machine controller, DC/DC controller, power battery management system, fuel cell controller etc.).

Control method of finished of the present invention may further comprise the steps:

1, reads in data

Entire car controller reads in driver's shift signal, driver's pedal signal and TTCAN bus communication data from digital quantity, analog quantity and TTCAN PORT COM.For example, entire car controller reads in driver's shift signal from the digital quantity port, reads in driver's pedal signal from the analog quantity port, reads in TTCAN bus communication data from the TTCAN PORT COM.In addition, according to the needs of different system, entire car controller can also read in the signal that electricity leakage sensor, braking pressure sensor etc. send from the analog quantity port, reads in from the digital quantity port to comprise signals such as motor status switches, high pressure powers on.

2, motor status switches

As Fig. 4, shown in Figure 5, the motor status handover module of entire car controller switches motor status according to driver's shift signal and driver's pedal signal between " driving, idling, slide, brake, move backward ".

Such as: entire car controller judges at first whether driver's shift signal is neutral, if it is idling that motor status then is set; Otherwise, judge further whether shift signal is backward gear, if motor status then is set is reversing; Otherwise, judge that further brake pedal whether greater than the braking threshold value, is braking if motor status then is set; Otherwise, further judge brake pedal whether smaller or equal to the braking threshold value, and acceleration pedal is greater than accelerating threshold value, if, motor status then is set for driving, otherwise, motor status is set for sliding.

3, driver's command interpretation

As Fig. 2, shown in Figure 6, the motor status signal that driver's command interpretation module arranges according to the motor status handover module, determine whether motor status is braking mode, if not braking mode, then be " idling ", " reversing ", " driving " or " sliding " state, this moment, the motor target torque was for driving target torque

$T_{\mathrm{qd}}^{*}={\mathrm{\αT}}_{\mathrm{qd},\max }---\left(1\right)$

α is driver's pedal position signal in the formula (1), span 0～1; T _{Qd, max}Being the motor maximum driving torque, as shown in Figure 7, is maximum driving torque T under the driving condition _{Qd, max}With motor speed n and motor-driven target torque

Corresponding relation figure, according to formula (1) and corresponding relation shown in Figure 7, can obtain driving target torque

Value.

As shown in Figure 6, if braking mode, this moment, the motor target torque was the motor braking target torque

$T_{\mathrm{qb}}^{*}=T_{\mathrm{qb},\max }\mathrm{\γ}---\left(2\right)$

T in the formula (2) _{Qb, max}Being maximum braking torque, as shown in Figure 8, is motor maximum braking torque T under the braking mode _{Qb, max}With motor speed n and motor braking target torque

Corresponding relation figure.

γ is the brake pedal coefficient in the formula (2), when not adopting the braking energy feedback strategy, and γ=0; When adopting tandem braking energy feedback strategy, γ obtains by following formula:

γ＝4(β-β ₁)(β-β ₂)(β ₁-β ₂) ^-2， （3）

β is brake pedal position signal in the formula (3), β ₁And β ₂Be the feedback braking policing parameter.This parameter influence car brakeing effect, demarcation obtains according to actual conditions.

4, SOC verification

As Fig. 2, shown in Figure 9, the SOC value that SOC verification module sends BMS, and TTCAN bus voltage, electrokinetic cell electric current carry out verification, checking procedure is as follows:

1) according to electrokinetic cell charging and discharging currents, voltage signal, use RLS(Recursive Least Squares Algorithm, the least square recursive algorithm) the current electrokinetic cell open circuit voltage of online estimation and on average discharge and recharge internal resistance, and in conjunction with electrokinetic cell open circuit voltage-SOC curve with discharge and recharge the anti-SOC of the pushing away value of internal resistance-SOC curve.Wherein, on average discharge and recharge the aviation value that internal resistance refers to power battery charging internal resistance under certain SOC and discharge internal resistance.

2) the SOC value that sends according to BMS, in conjunction with electrokinetic cell open circuit voltage-SOC curve with discharge and recharge internal resistance-SOC curve, extrapolate the electrokinetic cell open circuit voltage and on average discharge and recharge internal resistance.

3) according to step 2) in calculate the open circuit voltage obtain, on average discharge and recharge the SOC value that internal resistance and BMS send, calculate with respect to estimating the open circuit voltage that obtains in the step 1), on average discharging and recharging the relative error of internal resistance and SOC value.

4) if calculate open circuit voltage, on average discharge and recharge the relative error of three kinds of parameter values of SOC value that internal resistance and BMS send all less than 10%, then SOC verification module judges that the SOC value of BMS transmission is credible, otherwise SOC verification module adopts the SOC estimated valve that obtains in the step 1) to replace the SOC value of BMS transmission; The SOC value of determining transfers to equivalent hydrogen consumption by SOC verification module and optimizes distribution module.

5, road conditions adaptive equalization

As shown in figure 10, road conditions adaptive equalization module is according to the unit information that receives, at line computation car load auxiliary power P _Aux, DC/DC dynamic compensation timeconstant _Dc, and to electrokinetic cell SOC value, fuel battery performance decline compensates and the self adaptation adjustment accordingly.

Wherein, car load auxiliary power P _AuxCan adopt single order LPF algorithm to carry out online estimation according to the TTCAN bus data:

$P_{\mathrm{aux}}=\frac{P_{\mathrm{dc}}+P_{\mathrm{bat}}-P_{m,\mathrm{in}}}{{\mathrm{\τ}}_{\mathrm{aux}}s+1},---\left(4\right)$

P in the formula (4) _DcBe DC/DC horsepower output, P _BatBe electrokinetic cell horsepower output, P _{M, in}Be power input to machine, all can read τ from the TTCAN bus data _AuxBe filter constant.S is the plural variable of transfer function.

Afterwards, read data from the TTCAN bus, adopt the online recursive algorithm estimation of least square fuel cell U-I curve three parameter U ₀(open circuit voltage), R _Fc(ohmic internal resistance) and b(concentration polarization parameter).According to curve shown in Figure 11, calculate corresponding Δ τ _Dc1, Δ τ _Dc2With Δ τ _Dc3Value.Wherein, Δ τ _Dc1, Δ τ _Dc2With Δ τ _Dc3Be respectively fuel cell U-I curve three parameter U ₀, R _FcWith b and definite correction, with the fuel cell pile performance degradation, the strain of DC/DC dynamic compensation time constant is big, so that the pile horsepower output changes is more slow, thus the protection fuel cell.Therefore, Δ τ _Dc1With U ₀Successively decrease Δ τ _Dc2With R _FcIncrease progressively Δ τ _Dc3Increase progressively with b.Then, calculate DC/DC dynamic compensation timeconstant according to following formula _Dc:

τ _dc＝λ ₁Δτ _dc1+λ ₂Δτ _dc2+λ ₃Δτ _dc3+τ _dc0， （5）

λ in the formula (5) ₁, λ ₂, λ ₃Be fuel battery performance decline coefficient of weight: λ ₁=0.4, λ ₂=0.4, λ ₃=0.2.τ _dc0=5s。Consider the DC/DC target current correction of electrokinetic cell SOC balance Be calculated as follows:

${\mathrm{\ΔI}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}1}^{*}=\frac{{\mathrm{kK}}_p{P}_{\mathrm{mb}}^{*}}{(U_{\mathrm{ocv}}\mathrm{Qs}+k){\mathrm{\η}}_m}---\left(6\right)$

Q is the electrokinetic cell capacity in the formula (6), and k is the slope of electrokinetic cell optimal power-SOC curve and x axle intersection, K _pBe coefficient of correction, between the value 1～1.5,

Be motor braking power (taking absolute value), η _mBe electrical efficiency, s is the plural variable of transfer function, U _OcvBe the electrokinetic cell terminal voltage.Through type (6), when the car load braking energy is recycled to electrokinetic cell by motor, the corresponding part that reduces of fuel cell output power, thus prevent that electrokinetic cell SOC is too high.

6, the car load diagnosis is revised

As shown in figure 12, car load diagnosis correcting module is revised motor target torque and DC/DC target current according to the restriction of the operating range of each parts, prevents overvoltage, overcurrent and overheating problem.As shown in figure 13, be car load diagnosis modification method block diagram.The result of calculation of this car load diagnosis modification method is motor target torque diagnosis correction

With DC/DC target current diagnosis correction

Each variable meaning is among the figure:

λ _CLThe motor target torque coefficient of correction definite according to the electric leakage degree

λ _FcThe motor target torque coefficient of correction that the fuel cell diagnostic message is determined

λ _HLThe motor target torque coefficient of correction definite according to the hydrogen leak degree

λ _McuThe motor target torque coefficient of correction definite according to the MCU temperature

λ _{M, temp}The motor target torque coefficient of correction definite according to motor temperature

λ _TbatThe motor target torque coefficient of correction definite according to temperature of powered cell

λ _UbatThe motor target torque coefficient of correction definite according to bus voltage

μ _CLThe DC/DC target power coefficient of correction definite according to the electric leakage degree

μ _Dc1According to DC/DC outgoing current I _DcThe DC/DC target power coefficient of correction of determining

μ _Dc2According to the DC/DC work temperature _DcThe DC/DC target power coefficient of correction of determining

μ _Dc3According to DC/DC input voltage U _FcThe DC/DC target power coefficient of correction of determining

μ _FcThe DC/DC target power coefficient of correction that the fuel cell diagnostic message is determined

μ _HLThe DC/DC target power coefficient of correction definite according to the hydrogen leak degree

μ _TfcThe DC/DC target power coefficient of correction that the fuel cell cooling water temperature is determined

The DC/DC target current correction (A) that the fuel cell cooling water temperature is determined

The motor target torque correction (N.m) definite according to the MCU temperature

The motor target torque correction (N.m) definite according to motor temperature

The motor target torque correction (N.m) definite according to temperature of powered cell

7, equivalent hydrogen consumption is optimized distribution

As shown in figure 14, optimize in the distribution module in equivalent hydrogen consumption, the car load target power is optimized distribution between electrokinetic cell and fuel cell, make system's equivalence hydrogen consumption minimum, and maintenance SOC value balance, can optimize fuel cell system efficient to greatest extent like this, and guarantee that electrokinetic cell has enough electric weight, thus the dynamic property of assurance car load.Equivalence hydrogen consumption is optimized in the distribution at first needs to calculate electrokinetic cell optimal power P _{Bat, opt}:

$P_{\mathrm{bat},\mathrm{opt}}=\left\{\begin{array}{c}{U}_{\mathrm{bus},\min }(U_{\mathrm{ocv}}-U_{\mathrm{bus},\min })/R_{\mathrm{dis}},{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}\&le;x_{\min }\\ U_{\mathrm{ocv}}^2(1-{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;2})/\left({4R}_{\mathrm{dis}}\right),x_{\min }<{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}\&le;1\\ \mathrm{0,1}<{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}\&le;1/\left(\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{chg}}}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{dis}}}\right)\\ U_{\mathrm{ocv}}^2(1-{\left({\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{chg}}}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{dis}}}\right)}^2)/\left({4R}_{\mathrm{chg}}\right),1/\left(\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{chg}}}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{dis}}}\right)<{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}<x_{\mathrm{cax}}/\left(\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{chg}}}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{dis}}}\right)\\ -U_{\mathrm{bus},\max }(U_{\mathrm{bus},\max }-U_{\mathrm{ocv}})/R_{\mathrm{chg}},{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}\&GreaterEqual;x_{\max }/\left(\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{chg}}}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{dis}}}\right)\end{array}\right.---\left(7\right)$

U in the formula (7) _{Bus, min}Be bus voltage minimum value, U _{Bus, max}Be bus voltage maxim, U _OcvBe electrokinetic cell terminal voltage, R _DisBe discharge internal resistance, R _ChgBe the charging internal resistance, With Be the average discharge efficiency of electrokinetic cell and average charge efficient, K' ₁With x be custom parameter:

$\left\{\begin{array}{c}{\mathrm{<figure-callout\; id="1"\; label="K"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">K</figure-callout>}}_1^{\&prime;}=\mathrm{\&kappa;}\stackrel{\&OverBar;}{{\mathrm{\&eta;}}_{\mathrm{chg}}}\\ x_{\min }=\sqrt{1+{4U}_{\mathrm{bus},\min }(U_{\mathrm{bus},\min }-U_{\mathrm{ocv}})/\left(U_{\mathrm{ocv}}^2\right)}\\ x_{\max }=\sqrt{1+{4U}_{\mathrm{bus},\max }(U_{\mathrm{bus},\max }-U_{\mathrm{ocv}})/\left(U_{\mathrm{ocv}}^2\right)}\end{array}\right.,---\left(8\right)$

κ is coefficient of correction in the formula (8), and it is defined as:

κ＝1-2μ(SOC-0.5(SOC _H+SOC _L))(SOC _H-SOC _L)， （9）

μ is electrokinetic cell SOC balance coefficient of correction in the formula (9).SOC _HBe the higher limit of SOC, SOC _LLower limit for SOC.According to different road conditions, the value according to adjusting electrokinetic cell SOC balance coefficient of correction μ guarantees that SOC is in [SOC _L, SOC _H] scope within.As shown in figure 15, be when electrokinetic cell SOC balance coefficient of correction μ=0.6, the electrokinetic cell optimal power that provides and the result of calculation of SOC relation.

Can calculate DC/DC optimal objective power according to the electrokinetic cell optimal power For:

$P_{\mathrm{dc},\mathrm{opt}}^{*}=\max (\min (P_m^{*}/{\mathrm{\&eta;}}_m+P_{\mathrm{aux}}-P_{\mathrm{bat},\mathrm{opt}},P_{\mathrm{dc},\max }),P_{\mathrm{dc},\min })---\left(10\right)$

P in the formula (10) _{Dc, max}Be DC/DC maximum output power, P _{Dc, min}Be minimum output power, P _AuxBe car load auxiliary power (in road conditions adaptive equalization module, calculating), η _mBe electrical efficiency,

Being the drive motor target power, is the motor braking target torque With the product of motor actual speed, P _{Bat, opt}Be the electrokinetic cell optimal power.DC/DC dynamic object electric current

For:

${\mathrm{<figure-callout\; id="1"\; label="I\; dc"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">I</figure-callout>}}_{\mathrm{dc}}^1=P_{\mathrm{dc},\mathrm{opt}}^{*}/U_{\mathrm{bus}}---\left(11\right)$

U in the formula (11) _BusBe bus voltage.DC/DC dynamic object electric current is carried out first-order filtering, obtain the DC/DC target current

For:

$I_{\mathrm{dc}}^{*}=\frac{I_{\mathrm{<figure-callout\; id="1"\; label="dc"\; filenames="HDA0000053476110000071.png"\; state="\{\{state\}\}">dc</figure-callout>}1}^{*}}{{\mathrm{\&tau;}}_{\mathrm{dc}}s+1}---\left(12\right)$

τ in the formula (12) _DcBe DC/DC dynamic compensation time constant (in road conditions adaptive equalization module, calculating),

Be DC/DC dynamic object electric current.

8, entire car controller sends to electric machine controller and DC/DC controller with revised motor target torque and DC/DC target current respectively by the TTCAN bus, realizes the horsepower output control to motor and fuel cell.

The method of calculating of revised motor target torque and DC/DC target current is:

$\left\{\begin{array}{c}{I}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}}^{*}=I_{\mathrm{dc}}^{*}-{\mathrm{\&Delta;I}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}1}^{*}-{\mathrm{\&Delta;I}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}2}^{*}\\ T_{q,\mathrm{mod}\mathrm{ified}}^{*}=T_q^{*}-{\mathrm{\&Delta;T}}_{q,\mathrm{mod}\mathrm{ified}}^{*}\end{array}\right.,---\left(13\right)$

In the formula (13)

Be the motor target torque, it when braking mode is

All the other states are

Be motor target torque diagnosis correction. Be the DC/DC target current of unmodified,

Be the DC/DC target current correction of consideration electrokinetic cell SOC value balance, Be DC/DC target current diagnosis correction, Be drive motor target torque diagnosis correction.

Claims (6)

1. fuel cell hybrid control method of finished may further comprise the steps:

1) motor status handover module, driver's command interpretation module, power battery charged state verification module, road conditions adaptive equalization module, car load diagnosis correcting module and equivalent hydrogen consumption are set and optimize distribution module in entire car controller;

2) described entire car controller reads in driver's shift signal, driver's pedal signal and TTCAN bus communication data from digital quantity, analog quantity and TTCAN PORT COM, and wherein, TTCAN is time trigger-type controller local area network;

3) described motor status handover module switches motor status according to driver's shift signal and driver's pedal signal between " driving, idling, slide, brake, move backward ";

4) described driver's command interpretation module is determined motor status according to the motor status signal that the motor status handover module arranges, and then definite motor target torque;

5) described power battery charged state verification module SOC value that power battery management system is sent, and TTCAN bus voltage, electrokinetic cell electric current carry out verification, and wherein, the SOC value is the power battery charged state proof test value;

Wherein, the checking procedure of power battery charged state verification module is as follows:

1. use the current electrokinetic cell open circuit voltage of the online estimation of least square recursive algorithm and on average discharge and recharge internal resistance, and in conjunction with electrokinetic cell open circuit voltage-SOC curve with discharge and recharge the anti-SOC of the pushing away value of internal resistance-SOC curve;

2. the SOC value that sends according to power battery management system, in conjunction with electrokinetic cell open circuit voltage-SOC curve with discharge and recharge internal resistance-SOC curve, extrapolate the electrokinetic cell open circuit voltage and on average discharge and recharge internal resistance;

3. calculate the open circuit voltage obtain in 2., on average discharge and recharge the SOC value that internal resistance and power battery management system send according to step, calculate with respect to step and estimate the open circuit voltage that obtains in 1., on average discharge and recharge the relative error of internal resistance and SOC value;

If 4. the relative error of three kinds of parameter values is all less than 10%, then power battery charged state verification module judges that the SOC value that power battery management system sends is credible, otherwise the SOC estimated value that power battery charged state verification module adopts step to obtain in 1. replaces the SOC value of power battery management system transmission;

6) described road conditions adaptive equalization module is according to the unit information that receives, at line computation car load auxiliary power P _Aux, DC/DC dynamic compensation timeconstant _Dc, and to electrokinetic cell SOC value, fuel battery performance decline compensates and the self adaptation adjustment;

7) described car load diagnosis correcting module is revised motor target torque and DC/DC target current according to the restriction of the operating range of each parts;

8) described equivalent hydrogen consumption is optimized in the distribution module, and the car load target power is optimized distribution between electrokinetic cell and fuel cell, makes system's equivalence hydrogen consumption minimum, and keeps SOC value balance;

9) entire car controller sends to electric machine controller and DC/DC controller with revised motor target torque and DC/DC target current respectively by the TTCAN bus, realizes the horsepower output control to motor and fuel cell.

2. a kind of fuel cell hybrid control method of finished as claimed in claim 1, it is characterized in that: in the described step 3), the switch step of described motor status handover module is as follows:

1. judge whether driver's shift signal is neutral, if it is idling that motor status then is set, otherwise enters next step;

2. judge whether shift signal is backward gear, if motor status then is set is reversing; Otherwise enter next step;

3. whether judge brake pedal greater than the braking threshold value, if motor status then is set is braking; Otherwise enter next step;

4. judge brake pedal whether smaller or equal to the braking threshold value, and acceleration pedal is greater than accelerating threshold value, if, motor status then is set for driving, otherwise, motor status is set for sliding.

3. a kind of fuel cell hybrid control method of finished as claimed in claim 1, it is characterized in that: in the described step 4), described driver's command interpretation module is determined motor in idling, reversing, driving and sliding state following time, and then the motor target torque is for driving target torque

$T_{\mathrm{qd}}^{*}={\mathrm{\&alpha;T}}_{\mathrm{qd},\max }---\left(1\right)$

α is driver's pedal position signal in the following formula, span 0～1; T _{Qd, max}Be the motor maximum driving torque, according to full-throttle characteristics and the target torque graph of a relation of motor under driving condition, obtain driving target torque

Value;

Described driver's command interpretation module is determined motor in braking mode following time, and then the motor target torque is the braking target torque

$T_{\mathrm{qb}}^{*}=T_{\mathrm{qb},\max }\mathrm{\&gamma;},$ γ is the brake pedal coefficient in the following formula, T _{Qb, max}Be maximum braking torque, according to full-throttle characteristics and the target torque graph of a relation of motor under braking mode, obtain braking target torque

Value.

4. a kind of fuel cell hybrid control method of finished as claimed in claim 3 is characterized in that: described brake pedal coefficient gamma, and when adopting tandem braking energy feedback strategy, described brake pedal coefficient gamma obtains by following formula:

γ＝4(β-β ₁)(β-β ₂)(β ₁-β ₂) ^-2，

β is brake pedal position signal in the following formula, β ₁And β ₂Be the feedback braking policing parameter, this parameter influence car brakeing effect, demarcation obtains according to actual conditions.

5. a kind of fuel cell hybrid control method of finished as claimed in claim 1 is characterized in that: in the described step 6), and in described road conditions adaptive equalization module, described car load auxiliary power P _AuxAccording to the TTCAN bus data, adopt single order LPF algorithm to carry out online estimation:

$P_{\mathrm{aux}}=\frac{P_{\mathrm{dc}}+P_{\mathrm{bat}}-P_{m,\mathrm{in}}}{{\mathrm{\&tau;}}_{\mathrm{aux}}s+1},$

P in the following formula _DcBe DC/DC horsepower output, P _BatBe electrokinetic cell horsepower output, P _{M, in}Be power input to machine, all can read τ from the TTCAN bus data _AuxBe filter constant, s is the plural variable of transfer function;

Described DC/DC dynamic compensation timeconstant _DcBe calculated as follows:

τ _dc＝λ ₁Δτ _dc1+λ ₂Δτ _dc2+λ ₃Δτ _dc3+τ _dc0，

λ in the following formula ₁, λ ₂, λ ₃Be fuel battery performance decline coefficient of weight: λ ₁=0.4, λ ₂=0.4, λ ₃=0.2, τ _Dc0=5s, Δ τ _Dc1Be the U-I of fuel cell system parameter of curve open circuit voltage U ₀The correction, the Δ τ that determine _Dc2Be the U-I of fuel cell system parameter of curve ohmic internal resistance R _FcThe correction, the Δ τ that determine _Dc3Be the correction that the U-I of fuel cell system parameter of curve concentration polarization parameter b is determined, Δ τ _Dc1, Δ τ _Dc2With Δ τ _Dc3Change with the fuel cell pile performance degradation.

6. a kind of fuel cell hybrid control method of finished as claimed in claim 1, it is characterized in that: in the described step 9), the computing formula of revised described motor target torque and DC/DC target current is as follows:

$\left\{\begin{array}{c}{I}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}}^{*}=I_{\mathrm{dc}}^{*}-{\mathrm{\&Delta;I}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}1}^{*}-{\mathrm{\&Delta;I}}_{\mathrm{dc},\mathrm{mod}\mathrm{ified}2}^{*}\\ T_{q,\mathrm{mod}\mathrm{ified}}^{*}=T_q^{*}-{\mathrm{\&Delta;T}}_{q,\mathrm{mod}\mathrm{ified}}^{*}\end{array}\right.,$

In the following formula

Be the motor target torque,

Be motor target torque diagnosis correction,

Be the DC/DC target current of unmodified,

Be the DC/DC target current correction of consideration electrokinetic cell SOC value balance,

Be DC/DC target current diagnosis correction, Be drive motor target torque diagnosis correction.

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