CN107826101A

CN107826101A - A kind of series parallel hybrid power car threshold control strategy

Info

Publication number: CN107826101A
Application number: CN201710777115.5A
Authority: CN
Inventors: 秦东晨; 张东明; 程雷; 张姗; 胡朋磊; 潘守辰; 王然然
Original assignee: Zhengzhou University
Current assignee: Zhengzhou University
Priority date: 2017-09-01
Filing date: 2017-09-01
Publication date: 2018-03-23

Abstract

The invention discloses a kind of series parallel hybrid power car threshold control strategy.The strategy mainly includes 1）Determine the switching law between various mode of operations；2）Unit status control rule is determined under different working modes；3）The torque allocation rule between each assembly part of dynamical system is determined under different mode of operations；4）Simulink models are built in Matlab and generate control file.By in CRUISE softwares test simulation show that the strategy can be under conditions of vehicle driving requirements be met, ensure that super capacitor has good charge-discharge characteristic and electric quantity balancing characteristic, the good distribution of torque is realized, compared with real vehicle service data, vehicle fuel consumption per hundred kilometers reduces 5.57%.

Description

A kind of series parallel hybrid power car threshold control strategy

Technical field

The invention belongs to series parallel hybrid power car integrated vehicle control tactics field, more particularly to a kind of logic threshold Control strategy.

Background technology

Existing integrated vehicle control tactics, it is suffered from design and controls that rules and methods are simple, shadow of easy implementation Ring, so as to simplify control object and optimal control method, cause integrated vehicle control tactics exist control targe is single, control method not The problems such as comprehensively and practicality is bad；Therefore more comprehensive, practical, the efficient integrated vehicle control tactics of exploitation, preferably realize mixed The superior function of power bus safety, reliable, energy-conservation and environmental protection is closed, is still problem urgently to be resolved hurrily at present.

Hybrid power whole passenger vehicle control strategy, substantially it is a kind of distribution for controlling energy and management, optimization dynamical system The method of system work, what it can make from driver according to the road conditions of actual travel to parts such as accelerator pedal or brake pedals Reflection is set out, and is calculated the energy required for vehicle traveling, is then managed by reasonably planning machine driving and Electric Drive Power flow, energy output distribution is carried out to power source, coordinates the work of each part, it is such as minimum to complete expected control targe Fuel consumption, minimum discharge and excellent cornering ability etc..

With the continuous development of Technology of Hybrid Electric Vehicle condition, series parallel hybrid power car has changed into domestic new energy vapour The emphasis vehicle of car research, under the serious present situation of urban traffic blocking and environmental pollution, preferably city bus is promoted to realize Energy-saving and emission-reduction, there is very big practical development to be worth.

The present invention is using domestic a coaxial series parallel hybrid power bus as research object, to its hybrid power system On the basis of system analysis, a kind of series parallel hybrid power car threshold control strategy is proposed, up to the present, there is not yet Reported to research related to the present invention.

The content of the invention

It is an object of the invention in order to preferably realize series parallel hybrid power bus safety, reliable, energy-saving and environmental protection Superior function, the comprehensive, practical and efficient of full-vehicle control is realized, propose a kind of series parallel hybrid power car logic threshold control System strategy.

The purpose of the present invention can be achieved through the following technical solutions.

A kind of series parallel hybrid power car threshold control strategy, it is characterised in that comprise the following steps：

1) turned from operation of the driver to acceleration/brake pedal, the state-of-charge SOC of power supply, current vehicle speed and vehicle demand The basic parameter as full-vehicle control such as square；

2）According to step 1）Middle parameter determines different mode of operations；

3）According to step 1）Middle parameter determines automatic clutch and engine condition；

4）According to step 1）Torque distribution between middle each assembly part of parameter positive motion Force system；

5）Phase is built for this vehicle threshold control strategy in Matlab softwares according to the control rule of designed formulation Corresponding Simulink models simultaneously generate control file.

A kind of series parallel hybrid power car threshold control strategy according to claim 1, its feature exist In the step 1）Middle driver has the two kinds of operations of bend the throttle or brake pedal, and power supply state-of-charge SOC is provided with Upper lower limit value, SOC_high and SOC_low represent the upper lower limit value of set super capacitor electricity respectively, and set SOC_ High=0.8, SOC_low=0.4；Current vehicle speed has controlling value, is set according to the idling speed of engine；The torque of vehicle demand by The current output torque of main drive motor and the aperture of accelerator pedal are calculated.

A kind of series parallel hybrid power car threshold control strategy according to claim 1, its feature exist In the step 2）In mode of operation have pure motor drive mode, ISG electric power generations and motor drive mode, engine list Only drive pattern, joint drive pattern, engine driving and 6 kinds of mode of operations of power generation mode and braking mode.

A kind of series parallel hybrid power car threshold control strategy according to claim 1, its feature exist In the step 3）Middle automatic clutch has separation/closure two states, it is specified that " 0 " represents released state, and " 1 " represents closure State, the state of clutch is represented with Clutch_Stage；Engine has closing/startup two states, it is specified that " 0 " represents closing State, " 1 " represent starting state, and the state of engine is represented with Engine_Switch.

A kind of series parallel hybrid power car threshold control strategy according to claim 1, its feature exist In the step 4）Middle torque distribution includes driving torque distribution and regenerative brake torque distributes two kinds.

A kind of series parallel hybrid power car threshold control strategy according to claim 5, its feature exist In for driving torque, it is assumed that gas pedal aperture is A (%)：

T_req=A × T_max=A × (T_{e_max}+T_{m_max})

In formula, T_reqFor the driving torque (Nm) of vehicle demand；T_maxThe torque capacity that can be output for vehicle under current vehicle speed (N·m)；T_{e_max}The torque capacity (Nm) that can be exported for engine under current vehicle speed； T_{m_max}For main drive under current vehicle speed The torque capacity (Nm) that dynamic motor can export；

For regenerative brake torque：

In formula, T_{m_brake}For the regenerative brake torque (Nm) of main drive motor output；-T_{m_max}For main driving under current vehicle speed The maximum of motor output bears torque (Nm)；A is brake pedal aperture (%).

Compared with prior art, the invention has the advantages that：

By operation of the driver to acceleration/brake pedal etc., driving intention information is carried out according to pre-set rule Identification, determines the state of mode of operation and automatic clutch and engine, and then calculates required driving or braking moment simultaneously It is allocated；By in CRUISE softwares test simulation show the strategy can under conditions of vehicle driving requirements are met, Ensure that super capacitor has good charge-discharge characteristic and electric quantity balancing characteristic, realize the good distribution of torque, run with real vehicle Data are compared, and vehicle fuel consumption per hundred kilometers reduces 5.57%.

Brief description of the drawings

Fig. 1 is the threshold control Policy model that the present invention establishes.

Fig. 2 is the switching control flow chart of different working modes of the present invention.

Fig. 3 is regenerative brake torque distribution control flow chart of the present invention.

Fig. 4 is the input signal pre-processing module model that the present invention establishes.

Fig. 5 is the torque distribution control modular model that the present invention establishes.

Fig. 6 is series parallel hybrid power car power system architecture sketch.

Embodiment

Below in conjunction with the accompanying drawings and instantiation, the present invention will be further described.

Different working modes are determined with reference to Fig. 6 control flow charts 2.If driver's bend the throttle, illustrate that vehicle has drive Dynamic or acceleration demand, then vehicle demand torque is calculated according to accelerator pedal aperture：

T_req=A × T_max=A × (T_{e_max}+T_{m_max})

In formula, T_reqFor the driving torque (Nm) of vehicle demand；T_maxThe torque capacity that can be output for vehicle under current vehicle speed (N·m)；T_{e_max}The torque capacity (Nm) that can be exported for engine under current vehicle speed； T_{m_max}For main drive under current vehicle speed The torque capacity (Nm) that dynamic motor can export.

Gained torque and engine maximum/minimum output torque will be calculated（By tabling look-up to obtain）It is compared, and combines and work as The SOC of preceding super capacitor determines mode of operation.

If the torque of vehicle demand is less than the minimum output torque of engine, and super capacitor SOC is in middle high level, then Engine is operated alone, i.e., pure motor drive mode without starting by main drive motor；If now SOC<SOC_low, then, Then need to control engine start, super capacitor is charged by driven by engine ISG, then by the only self-driving vehicle of main drive motor , i.e. ISG electric power generations and motor drive mode.

If the torque of vehicle demand is higher than the minimum output torque of engine but is less than maximum output torque, then needs start Machine starts, if SOC level is very high, then engine only needs output torque that vehicle is operated alone, i.e. pattern is operated alone in engine； If SOC<SOC_high, in order to maintain preferable electric quantity balancing characteristic, engine needs multi output partial torque to be charged, that is, sent out Motivation driving and charge mode.

If vehicle needs torque higher than the maximum output torque of engine, it is necessary to control engine and main drive motor simultaneously Vehicle traveling is driven, that is, combines drive pattern.

If driver's brake pedal, illustrate that vehicle has braking deceleration demand, i.e. braking mode；If believe without driving Number also brakeless signal, then vehicle sliding.

It is 700r/min according to the idling speed of studied hybrid power system engine, it is 21km/h to be converted into speed, So choose 21km/h be speed condition controlling value, it is contemplated that clutch from be separated to combine during exist one sliding State, for setting speed between 18 ~ 21km/h, clutch enters line slip, i.e. hysteresis.

Regulation automatic clutch has separation/closure two states, it is specified that " 0 " represents released state, and " 1 " represents closed form State, the state of clutch is represented with Clutch_Stage；Engine has closing/startup two states, it is specified that " 0 ", which represents, closes shape State, " 1 " represent starting state, and the state of engine is represented with Engine_Switch.

The state of so clutch and engine both parts controls the rule to be：

If speed >=21km/h, Clutch_Stage=1, Engine_Switch=1；

If 21km/h >=speed >=18km/h, hysteresis；

If speed<18km/h and now SOC >=0.6 (middle high level), Clutch_Stage=0, Engine_Switch=0；

If speed<18km/h and now 0.6>SOC >=0.4, hysteresis；

If speed<18km/h and now SOC<0.4, Clutch_Stage=0, Engine_Switch=1；

Driving torque allocation rule：

When Clutch_Stage=0 (automatic clutch separation)：

If SOC >=0.4, T_m=T_req, T_e=T_isg=0；

If SOC<0.4, then T_e=-T_isg=T_{e_max}, T_m=T_req；

When Clutch_Stage=1 (automatic clutch closure)：

If T_req≥T_{e_max}And SOC >=0.4, then T_e=T_{e_max}, T_m=T_req-T_{e_max},T_isg=0；

If T_req≥T_{e_max}And SOC<0.4, then T_e=T_{e_max}, T_m=(T_req-T_{e_max})× 0.5,T_isg=0；

If T_{e_min}≤T_req<T_{e_max}And SOC >=0.8, then T_e=T_req, T_m=T_isg=0；

If T_{e_min}≤T_req<T_{e_max}And 0.4≤SOC<0.8, then T_e=T_{e_max}, T_m=0, T_isg=T_req-T_{e_max}；

If T_{e_min}≤T_req<T_{e_max}And SOC<0.4, then T_e=T_{e_max}, T_m=0, T_isg=T_req- T_{e_max}；

If T_req<T_{e_min}And SOC >=0.8, then T_e=T_isg=0, T_m=T_req；

If T_req<T_{e_min}And 0.4≤SOC<0.8, then T_e=T_{e_min}, T_m=0, T_isg=T_req-T_{e_min}；

If T_req<T_{e_min}And SOC<0.4, then T_e=T_{e_min}, T_m=0, T_isg=T_req-T_{e_min}.In formula, T_reqFor vehicle demand Driving torque (Nm)；T_{e_max}For the maximum output torque (Nm) of present engine；T_{e_min}For the minimum of present engine Output torque (Nm)；T_eFor engine target operation torque (Nm)；T_mFor main drive motor target operation torque (Nm)； T_isgFor ISG target operations torque (Nm).

Flow chart 3 and studied series parallel hybrid power car practical operation situation are compareed with reference to Fig. 6, only when speed height When 10km/h and SOC value small limit value thereon, energy regenerating is carried out using braking mode, now main drive motor exports Negative torque, charged as generator operation for super capacitor, other states are without energy regenerating.

In order to preferably keep the electric quantity balancing of super capacitor, can be reached more by the way of engine auxiliary power generation Good charging effect；If during regenerative braking, the SOC of super capacitor<SOC_low, then not exported merely with main drive motor negative Torque generates electricity, and starts driven by engine ISG and generate electricity, and to rise to the speed of super capacitor charging, quickly improves it SOC value.

Regenerative brake torque allocation rule is：

As 0.4≤SOC<When 0.8, without starting engine auxiliary power generation：

If brake pedal aperture A >=50%, T_{m_brake}=-T_{m_max}；

If brake pedal aperture A<50%, then T_{m_brake}=-T_{m_max}×A×0.2；

Work as SOC<When 0.4, start engine and ISG auxiliary power generations：

If brake pedal aperture A >=50%, T_{m_brake}=-T_{m_max}, T_e=T_{e_min}, T_isg=-T_{e_min}；

If brake pedal aperture A<50%, then T_{m_brake}=-T_{m_max}× A × 0.2, T_e=T_{e_min}, T_isg=-T_{e_min}；

In formula, T_{m_brake}For the regenerative brake torque (Nm) of main drive motor output；-T_{m_max}For main driving under current vehicle speed The maximum of motor output bears torque (Nm)；A is brake pedal aperture (%)；T_{e_min}Turn for the minimum output of present engine Square (Nm)；T_eFor engine target operation torque (Nm)；T_isgFor ISG target operations torque (Nm).

According to designed torque allocative decision and control rule, logic threshold full-vehicle control plan is built in Matlab Simulink models slightly, as shown in figure 1, the model is made up of input signal pre-processing module and torque distribution control module, The input control signal of whole control strategy is current vehicle speed, super capacitor SOC, main drive motor rotating speed, acceleration（Throttle）Step on Plate aperture and braking（Brake）Pedal aperture；Output control signal is that engine exports, main drive motor exports, ISG motors are defeated Go out, tail-off state and automatic clutch state, this model can realize to engine, main drive motor, ISG motors and from The control of four parts such as dynamic clutch.

Input signal pre-processing module is the signal transacting before torque distributes, and certain meter is mainly carried out to input signal Calculate or table look-up processing, obtain some the torque variables used in torque distribute module, and complete automatic clutch and engine State judges control；As shown in figure 4, input signal pre-processing module includes automatic clutch/engine control module, torque meter Calculate module two parts.

Automatic clutch/engine control module is to judge clutch of lower a moment according to current vehicle speed and super capacitor SOC Separation/closure state and engine on/off state, for dynamical system torque distribution equip；Mainly include speed Condition criterion pattern and SOC condition criterion patterns, are built fully according to the control rule of previously described mistake.

Vehicle row is calculated according to the output torque and accelerator pedal aperture of current main drive motor in torque calculation module Required torque is sailed, and maximum/minimum output torque, the main drive motor of present engine are obtained by a series of computation of table lookup Maximum output torque and ISG the parameter such as maximum output torque, and these torque parameters are sent to follow-up module and carried out Torque distributes；Wherein 5 table look-up modules（Look_Up modules）Data source be engine, main drive motor and ISG motors Universal characteristic data.

As shown in figure 5, torque distribution control module include vehicle operation mode decision module, driving torque distribute module, Regenerative brake torque distribute module, slide control module and parking control module.

Mode of operation determination module be according to the signals such as current vehicle speed, acceleration/brake pedal aperture driver is intended into Row judges, determines the active operation mode of vehicle；When car accelerator pedal aperture is not zero, that is, when signal for faster be present, vehicle Operation in the drive mode, is then driven the distribution of torque；When car brake pedal aperture is not zero, that is, brake signal be present When, vehicle runs the distribution for then carrying out regenerative brake torque in the braking mode；When accelerator pedal and brake pedal are without dynamic Make, i.e., in the absence of signal for faster or brake signal when, then current vehicle condition is judged according to speed, if speed be 0, then car In sliding under control model, otherwise stop.

Driving torque distribute module and regenerative brake torque distribute module are the cores of whole threshold control strategy, Above designed driving torque allocation rule and regenerative brake torque allocation rule are embodied respectively；Divide again in the two modules Do not include the control module to engine, main drive motor volume ISG three power parts of motor, control the torque of three respectively Output；It is to judge whether to need to carry out regenerating braking energy recovery according to current vehicle speed and super capacitor SOC to slide control module, If desired, then the negative torque of main drive motor output is controlled to recover energy.

It should be understood that the invention is not limited in series parallel hybrid power car logic threshold in above-mentioned specific embodiment Control strategy, every those skilled in the art can also be made on the premise of without prejudice to spirit of the invention equivalent variations or Modification, these equivalent deformations or modification are all contained in the application claim limited range.

Claims

1. a kind of series parallel hybrid power car threshold control strategy, it is characterised in that comprise the following steps：

1）Turned from operation of the driver to acceleration/brake pedal, the state-of-charge SOC of power supply, current vehicle speed and vehicle demand The basic parameter as full-vehicle control such as square；

A kind of 2. series parallel hybrid power car threshold control strategy according to claim 1, it is characterised in that The step 1）Middle driver has the two kinds of operations of bend the throttle or brake pedal, and power supply state-of-charge SOC is provided with upper Lower limit, SOC_high and SOC_low represent the upper lower limit value of set super capacitor electricity respectively, and set SOC_high =0.8, SOC_low=0.4；Current vehicle speed has controlling value, is set according to the idling speed of engine；Vehicle demand torque is by current The output torque of main drive motor and the aperture of accelerator pedal are calculated.

A kind of 3. series parallel hybrid power car threshold control strategy according to claim 1, it is characterised in that The step 2）In mode of operation there is pure motor drive mode, ISG electric power generations and motor drive mode, engine individually to drive Dynamic model formula, joint drive pattern, engine driving and 6 kinds of mode of operations of power generation mode and braking mode.

A kind of 4. series parallel hybrid power car threshold control strategy according to claim 1, it is characterised in that The step 3）Middle automatic clutch has separation/closure two states, it is specified that " 0 " represents released state, and " 1 " represents closed form State, the state of clutch is represented with Clutch_Stage；Engine has closing/startup two states, it is specified that " 0 ", which represents, closes shape State, " 1 " represent starting state, and the state of engine is represented with Engine_Switch.

A kind of 5. series parallel hybrid power car threshold control strategy according to claim 1, it is characterised in that The step 4）Middle torque distribution includes driving torque distribution and regenerative brake torque distributes two kinds.

A kind of 6. series parallel hybrid power car threshold control strategy according to claim 5, it is characterised in that For driving torque, it is assumed that gas pedal aperture is A (%)：

T_req=A × T_max=A × (T_{e_max}+T_{m_max})

In formula, T_reqFor the driving torque (Nm) of vehicle demand；T_maxThe torque capacity that can be output for vehicle under current vehicle speed (N·m)；T_{e_max}The torque capacity (Nm) that can be exported for engine under current vehicle speed；T_{m_max}For main driving under current vehicle speed The torque capacity (Nm) that motor can export；

For regenerative brake torque：

In formula, T_{m_brake}For the regenerative brake torque (Nm) of main drive motor output；-T_{m_max}For main driving electricity under current vehicle speed The maximum of machine output bears torque (Nm)；A is brake pedal aperture (%).