KR20190081379A - Management method for battery SOC of hybrid electric vehicle - Google Patents

Abstract

The present invention relates to a battery state of charge (SOC) management method for a hybrid electric vehicle (HEV) and an objective of the present invention is to provide a battery SOC management method for an HEV, which expands an electric vehicle (EV) drive section not operating an engine while managing a battery SOC at a predetermined level or more during driving in a congested section and therethrough non-driving fuel loss is reduced and mileage is increased. To this end, the battery SOC management method for an HEV comprises the following steps of a control unit: receiving information about a front road placed in the front side of the vehicle on a driving path from a navigator to determine whether the front road is a congested section; predicting and determining an SOC change when driving the congested section in an EV mode when the front road is determined to be a congested section; comparing a preset reference SOC value with a (battery SOC - ΔSOC), which is an SOC prediction value when driving the congested section in the EV mode, as a difference between the current battery SOC and the determined SOC change (ΔSOC); and controlling the vehicle to drive the congested section in the EV mode when the (battery SOC - ΔSOC) is greater than the reference SOC value.

Description

[0001] The present invention relates to a method of managing a battery SOC of a hybrid vehicle,

The present invention relates to a method of managing a battery SOC of a hybrid vehicle, and more particularly, to a method of managing a battery SOC of a hybrid vehicle in which a battery SOC can be maintained at a predetermined level or more during a congestion zone travel, To a method of managing battery SOC of a hybrid vehicle in which driving fuel loss can be reduced and fuel economy can be improved.

Recently, electric vehicles and hybrid vehicles with excellent fuel efficiency have been developed and are attracting attention.

An electric vehicle refers to a vehicle that generates driving torque of the vehicle only by a motor, and a hybrid vehicle refers to a vehicle that generates driving torque of the vehicle by an engine and a motor.

In the hybrid vehicle, it is possible to maximize the fuel consumption of the hybrid vehicle as well as to output the optimum torque according to how the engine and the motor that drive the vehicle are operated in harmony.

Hybrid vehicles can be composed of engines and motors in various structures. For example, TMED (Transmission Mounted Electric Device) type hybrid system in which an engine and a motor are connected through an engine clutch and a transmission is connected to a motor output side Is known.

The TMED type hybrid system is composed of an engine and a motor which are driving sources for running the vehicle, an engine clutch interposed between the engine and the motor, a transmission connected to the motor output side, an inverter for driving the motor, Lt; / RTI >

In addition, the hybrid system of the TMED type includes a hybrid starter and generator (hereinafter, referred to as 'HSG') connected to the engine so as to be able to transmit power and to start the engine or to generate power by the torque transmitted from the engine can do.

HSG can be used to control the engine speed because it is connected to the engine so that it can be always powered.

The engine clutch is connected or disconnected to connect or disconnect the engine and the motor in a power-transferable manner. The inverter converts the direct current of the battery into a three-phase alternating current for driving the motor and applies the alternating current to the motor.

The transmission transmits the power of the motor or the combined power of the engine and the motor to the driving wheel through the driving shaft, and an automatic transmission (AT) or a double clutch transmission (DCT) may be used.

Vehicles equipped with such hybrid systems, that is, hybrid vehicles such as HEVs and PHEVs, use an EV (Electric Vehicle) mode, which is a pure electric vehicle mode that uses only the power of a motor, or a combination of engine power and motor power The vehicle can be driven in a HEV (Hybrid Electric Vehicle) mode.

For example, if the driver's requested torque is large, the EV mode can be switched to the HEV mode, and conversely, if the driver's requested torque is small, the HEV mode can be switched to the EV mode.

When the vehicle is braked or coasting due to inertia, a regenerative mode is performed in which the kinetic energy of the vehicle is recovered through a motor to charge the battery. In the regenerative mode, kinetic energy of the vehicle is transmitted through the vehicle wheel The motor operates as a generator to charge the battery connected through the inverter.

On the other hand, in the hybrid vehicle, when the state of charge (hereinafter referred to as SOC) is low, control to defend SOC is performed so that the SOC is not reached.

For example, if the current battery SOC is lower than the predetermined idle charge SOC when the vehicle is running or stopping, idle charging can be performed for SOC protection.

Here, the SOC defense means that the battery SOC is kept not lowered to a certain level for the purpose of battery protection or the like.

The charging of the idle means charging the battery by driving the engine in an idle state to protect the battery when the battery SOC becomes lower than the idle charge SOC during driving or stopping the vehicle.

That is, if the battery SOC is lower than the idle charging SOC for battery protection in the TMED hybrid vehicle, the engine is operated in the idle state after the engine is started by the HSG during the stoppage, and then the HSG receives the engine torque Charge the battery.

In this idle charging process, when the engine clutch is released, the HSG receives the engine torque and operates as a generator. Then, when the battery SOC becomes higher than the idle charging SOC, the engine is turned off to terminate the idle charging.

At this time, since the engine power is not used to drive the vehicle, the engine fuel consumption at idle charging becomes a non-driven fuel loss.

It is known that the EV line is down-adjusted (pulling the engine-on point) to defend the SOC, and the engine is started even after the low vehicle speed and low APS (Acceleration Position Sensor) The engine torque induces an engine lock-up which causes the motor (drive motor) to operate as a generator.

The EV line defines the conversion condition from the EV mode to the HEV mode, and the boundary line on the graph in which the EV mode and the HEV mode are switched for various variables is defined as an EV line.

The conditions for switching from EV mode to HEV mode may include various variables, and downgrading the EV line means adjusting the EV line to switch from HEV mode to lower variable conditions.

An example of the EV line may be a boundary line connecting the vehicle speed at which the EV mode and the HEV mode are switched in the power map in which the required power is mapped according to the vehicle speed and the SOC, and the map value for each SOC.

At this time, the downward direction of the EV line may be a condition for switching from the EV mode to the HEV mode, that is, lowering the power value for the vehicle speed at which the engine is started and the power value for each SOC.

In this way, while the EV line is turned down and the engine is turned on / off repeatedly, SOC protection can be performed to maintain the battery SOC higher than the idle charging SOC.

At this time, part of the engine power during the operation after starting the engine is used to drive the driving motor as a generator (used for battery charging and SOC management), and the other is used as driving power for driving the vehicle.

In addition, to protect the battery, stepwise SOC defense control is performed in the order of the EV line down, the engine operation point up, and the upshift delay in the order of the SOC use area.

However, in the related art, SOC defense control is performed using only the current battery SOC that does not consider the situation of the front road at all. Particularly, when the battery SOC is low in a low vehicle speed condition where the vehicle is currently traveling in a stagnant region, And enters control.

However, as described above, there is a problem in that non-driving fuel loss occurs during the control for SOC defense. Therefore, if the SOC defense entry is made taking into consideration only the current battery SOC as in the prior art, (Such as when driving in a stagnant region), which causes a problem of lowering fuel efficiency of the vehicle due to unnecessary fuel consumption.

For example, when an idle charge for SOC protection is used, the engine is operated as idle to consume fuel, but the engine power at this time is not used for driving the vehicle, so there is a problem of non-driven fuel loss.

In addition, if the EV line is adjusted downward for SOC protection, the engine is frequently turned on / off in a short time interval. If there is a short and frequent engine on / off repetition in the stagnant region, the HSG frequently consumes battery power There is a problem of power overuse.

In addition, in the congestion section, the driver often operates the accelerator pedal and the brake pedal. Frequent repetition of deceleration after acceleration occurs when the brake pedal is operated within a short time after the accelerator pedal is operated.

If, for example, the driver operates the brake pedal within a short time after operating the accelerator pedal, if the deceleration is performed within a short time after acceleration with the EV line down for SOC protection, There is a problem that charging is impossible and only non-driving fuel loss occurs.

That is, since the engine is turned on for a short time and then turned off again, not only the power consumption of the HSG for starting the engine but also the engine may be turned off before the engine clutch is connected after starting the engine. But the battery is not charged by the motor (drive motor).

Further, although there is a possibility that the SOC can be raised in the engine part load mode after escaping the stagnant region in the past, if the battery SOC is low in the low vehicle speed state where the vehicle is traveling in the stagnant region, There is a problem that the fuel economy is deteriorated because it is determined that the SOC defense control is entered only in the current SOC situation.

FIG. 1 is a diagram illustrating a battery SOC management state according to the prior art, showing that SOC protection is achieved by repeating short engine on / off through EV line down adjustment.

As shown in the figure, while the vehicle is traveling in the congestion section, the engine SOC is maintained higher than the idle charging SOC by repeating the engine on / off. However, in a state where the EV line is downward for SOC defense, Similarly, if the engine is immediately turned off before the engine clutch is engaged after the engine is turned on, the motor power generation after the engine lock-up and the battery charging are impossible, so that the non-driving fuel loss consuming only the fuel increases.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in order to solve the above problems, and it is an object of the present invention to provide a navigation system and a navigation system, which are capable of detecting a road situation ahead by using navigation information in a hybrid vehicle performing battery SOC defense control, The present invention provides a method of managing a battery SOC of a hybrid vehicle in which an EV running period in which an engine is not driven can be expanded as compared with the prior art, have.

In order to achieve the above object, according to an embodiment of the present invention, there is provided a navigation system comprising: a control unit receiving information on a forward road located in front of a vehicle on a driving route from a navigation device, and determining whether the forward road is a congestion period; Estimating and determining an SOC change amount in the EV mode driving of the congestion section when it is determined that the control section is the congestion section; Comparing the current battery SOC and the determined SOC change amount (DELTA SOC) with a predetermined SOC reference value, which is an SOC predicted value at the EV mode running time of the congestion section; And controlling the vehicle so that the controller travels in an EV mode in a congestion section if the battery SOC -? SOC 'is higher than the SOC reference value.

Thus, according to the method for managing the battery SOC of the hybrid vehicle according to the present invention, the hybrid road which performs the battery SOC defense control judges the road condition ahead by using the navigation information, and the entry criterion of the SOC defense control during the congestion road running It is possible to expand the EV running period in which the engine is not driven, compared to the conventional EV running period, thereby reducing the non-driving fuel loss and improving the fuel consumption.

1 is a diagram illustrating a battery SOC management state according to the prior art.
2 is a configuration diagram of a system for performing an SOC management method according to an embodiment of the present invention.
3 is a flowchart showing an SOC management method according to an embodiment of the present invention.
4 is a diagram illustrating a battery SOC management state according to the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art can easily carry out the present invention. However, the present invention is not limited to the embodiments described herein but may be embodied in other forms.

Throughout the specification, when an element is referred to as "comprising ", it means that it can include other elements as well, without excluding other elements unless specifically stated otherwise.

The present invention can extend the EV traveling period in which the battery SOC can be maintained at a certain level or higher during the idle running and can not drive the engine, thereby reducing the non-driving fuel loss and improving the fuel economy. And to provide a management method.

FIG. 2 is a configuration diagram of a system for performing an SOC management method according to an embodiment of the present invention, FIG. 3 is a flowchart illustrating an SOC management method according to an embodiment of the present invention, Fig.

2, the navigation apparatus 10, the control unit 20, the engine 31 and the drive motor 33 that are the driving source of the vehicle, and the engine clutch 32 (interposed between the engine 31 and the drive motor 33) An inverter 41 for driving the HSG 34 as a starter generator for starting the engine and charging the battery (charging the battery), a drive motor 33 and an HSG 34, and a drive motor 33 And a battery 42 connected to the HSG 34 in a dischargeable manner.

First, the battery SOC management method of the present invention can be started by a user (for example, a driver) setting a route from a current position of the hybrid vehicle to a destination.

At this time, if the user selects a destination via the navigation device 10, the navigation device 10 confirms the current position of the vehicle from the GPS signal received through the GPS receiver, and then transmits the 3D map data and the real- The route from the current position of the vehicle to the destination selected by the user can be calculated.

The real-time traffic information may be TPEG (Transport Protocol Expert Group) data, for example.

Since the navigation device 10 includes the GPS receiver, the navigation device 10 acquires the vehicle position information, that is, the current position information of the vehicle, from the GPS signal received through the GPS receiver, and transmits the information to the control unit 20, And information on the front road along the route based on the current position of the vehicle.

Here, the information on the forward road may include a road inclination angle and an average vehicle speed, which is real-time traffic information.

Accordingly, the control unit 20 receives the necessary information such as the vehicle position information, the route information and the information about the front road from the navigation device 10, compares the average vehicle speed among the information about the front road at the current vehicle position with the set vehicle speed If the average vehicle speed is equal to or lower than the set vehicle speed, it is determined that the front road is the congestion section (S11).

If the average vehicle speed is higher than the set vehicle speed, the control unit 20 performs the existing SOC defense control. For example, after the engine 31 is turned on, the controller 20 charges the battery by the HSG 34 (Engine lock-up charging) by the drive motor 33 after the engine 31 is turned on and the engine clutch 32 is connected to the engine 20, and the battery SOC can be managed using the engine 20.

On the other hand, if it is determined that the front road is the congestion section, the SOC variation amount (ΔSOC) when the vehicle travels in the EV mode in the forward congestion section is predicted and determined in a step S12.

In order to predict and determine the SOC change amount? SOC during the EV mode running of the congestion section, when the controller 20 determines that the forward road is a congestion section, the controller 20 determines whether the average vehicle speed v is equal to or greater than the settling speed The length d of the congestion section is determined and the time t required for passing the congestion section at the average vehicle speed is calculated by dividing the distance d of the congestion section by the average vehicle speed v.

The time (t) taken to pass through the congestion section can be calculated by the following equation (1).

[Equation 1]

t = d / v

Here, v represents the average vehicle speed and d represents the distance of the congestion section (i.e., the length of the congestion section).

Further, the control unit 20 calculates the travel energy E of the vehicle that reflects the forward road situation and the traffic situation on the basis of the vehicle position information and the forward road information received from the navigation device 10 and the pre-stored setting information do.

That is, in the present invention, when the control unit 20 uses the vehicle position information transmitted from the navigation device 10, information about the forward road on the route, and pre-stored setting information, And calculates the energy (E).

Here, the setting information includes information to be inputted and stored in advance in the control unit 20 for use in calculating the running resistance of the vehicle, such as air density p, air resistance coefficient C _d , The weight of the vehicle m, the acceleration of gravity g, the radius of the tire r or the radius r of the road and the road surface friction coefficient (or tire friction coefficient).

Various methods are known for calculating the travel energy E while the vehicle travels along a predetermined path including the hybrid vehicle. In the present invention, the vehicle travels in the front congestion section at the average vehicle speed v Assuming that the travel energy E required for traveling while receiving the travel resistance R _t for the time t required for passing through the distance d of the congestion section is obtained in real time by the following equation and used .

In the present invention, the traveling energy E means driving energy necessary for the vehicle to pass through the stagnation zone of the front road along the traveling route set through the navigation device 10. [

Also, the travel energy E is a value estimated by calculating and estimating the energy required while passing through the stagnation region, and can be calculated as a value corresponding to the running resistance R _t considering the road situation ahead and the traffic situation have.

Equation (2) below is an equation that can calculate the traveling energy (E) in the present invention.

&Quot; (2) "

E = R _t x v x t

Here, v represents an average vehicle speed, t represents a time calculated by the above equation (1), that is, a time taken to pass through a stagnation zone, and R _t represents a total running resistance when passing through a stagnation zone .

The concept of integrating the power W to calculate the traveling energy E in the above Equation 2 is used and the power P is expressed by the equation of P = F x v = R _t x v Where the running resistance R _t is the value of the force F and the unit of the running resistance R _t is the unit of the force F. [

Running resistance (R _t) are to the frictional resistance of the driving system according to the air resistance (R _a), the vehicle speed according to the vehicle speed as shown in equation (3) of the vehicle (R _f), the rolling resistance due to friction between the tire and the road surface (R _r ), And a slope resistance (R _g ) according to a road inclination angle.

The running resistance R _t is calculated using the vehicle position information transmitted from the navigation device 10, information about the front road on the route, and pre-stored setting information.

Here, the information on the front road may include the average vehicle speed v and the road inclination angle [theta].

The running resistance R _t can be expressed by the following equation 3 and the running resistance R _t can be calculated using the average vehicle speed v, the road inclination angle θ, and setting information.

&Quot; (3) "

R _t = R _r + R _a + R _f + R _g

Here, R _r represents the rolling resistance, R _a represents the air resistance, R _f represents the frictional resistance, and R _g represents the slant resistance.

The rolling resistance R _r , air resistance R _a , frictional resistance R _f and slope resistance R _g can be calculated by the following equations (4) to (7).

&Quot; (4) "

&Quot; (5) "

&Quot; (6) "

&Quot; (7) "

In calculating the rolling resistance (R _r ) and the slope resistance (R _g ), μ is the road friction coefficient (or tire friction coefficient), m is the weight of the vehicle, g is the gravitational acceleration, .

In calculating the air resistance R _a , ρ represents the air density, C _d represents the air resistance coefficient, A represents the area of the front surface of the vehicle, and v represents the vehicle speed, ie, the average vehicle speed.

The vehicle speed v may be an average vehicle speed of the congestion period, which is real-time traffic information indicating traffic conditions on the road ahead. The control unit 20 receives information on the average vehicle speed included in the TPEG data from the navigation device 10, (R _t ).

The frictional resistance R _f means the frictional resistance of the driving system of the hybrid vehicle, and can be obtained, for example, by Equation (6).

Equation (6) is a function of the vehicle speed, and the friction resistance R _f can be obtained from the value according to the vehicle speed, that is, the value according to the average vehicle speed v in the congestion section.

In Equation (6), _{" b &quot}; represents the coefficient of friction of the in-vehicle driving system including the bearing, and is a value previously obtained and used for the driving system of the vehicle.

The above-mentioned ρ and C _d , A, μ, m, and g are setting information previously input and stored in the control unit 20.

The road inclination angle? Refers to the inclination angle of the road ahead of the vehicle on the basis of the present position of the vehicle. The control unit 20 receives from the navigation device 10 a traveling resistance and traveling energy (E).

The road inclination angle? May be an average inclination angle in the congestion section taken from the information on the front road received from the navigation device 10. [

The method of calculating the travel energy of the hybrid vehicle according to the present invention is not limited to the above-described method. For example, the calculation method of the travel energy may be a known method known to those skilled in the art One can be adopted and used.

Next, when the travel energy is obtained as described above, the controller 20 divides the travel energy by the total battery energy, and estimates and calculates? SOC, which is the value of the battery SOC change amount during traveling in the stagnation region.

Here, the total battery energy is specification information unique to the battery mounted on the vehicle, which is a known value, and is stored and used in advance in the control unit 20. [

If the ΔSOC value is determined as described above, the controller 20 determines the difference between the present battery SOC and ΔSOC, that is, the battery SOC-ΔSOC value as the set SOC reference value (first SOC reference value) (S13). If the value of battery SOC -? SOC is higher than the idle charging SOC, control is made so that the vehicle is driven in the EV mode (S14).

That is, when the value of the battery SOC -? SOC is higher than the idle charging SOC, the battery SOC is in a sufficient state. Therefore, when the vehicle travels in the stagnation region ahead of the vehicle, the driving motor 33 In the EV mode.

If the value of the battery SOC -? SOC is below the idle charge SOC, the controller 20 compares the value of the battery SOC -? SOC with the minimum SOC of the battery, which is another SOC reference value (second SOC reference value) It is determined whether the vehicle can travel in the EV mode (S15, S16).

Here, if the value of battery SOC -? SOC is higher than the minimum SOC of the battery, the controller 20 controls the vehicle to travel in the EV mode (S17).

On the other hand, if the value of the battery SOC -? SOC is less than the minimum SOC of the battery usable, the conventional SOC defense control is performed. For example, after charging the battery 31 by the HSG 34 (Engine lock-up charging) by the drive motor 33 after the engine 31 is turned on and the engine clutch 32 is engaged, and the battery SOC is managed using the engine 20 .

In the present invention, the minimum usable SOC of the battery is determined as a value obtained by adding a margin value? To a minimum SOC value, which is a specific value of a battery mounted on the vehicle, and is used in the control unit 20.

The margin value? Is an SOC value by which the HSG 34 can supply the electric power to the HSG 34 by the HSG 34 for a predetermined number of times, that is, the HSG 34 can start the engine 31 a predetermined number of times Lt; RTI ID = 0.0 > SOC < / RTI >

As described above, according to the present invention, the SOC predicted value at the time of the EV mode driving of the congestion section reflecting the forward road situation and the traffic situation, that is, the battery SOC -? SOC value is used, The vehicle is driven in the EV mode.

That is, if the 'battery SOC -? SOC' is higher than the idle charging SOC, it is controlled to the EV mode, and if it is lower than the idle charging SOC,

As described above, in the present invention, it is determined whether or not the EV mode can be traveled by using the SOC predicted value when the congestion period is not the current battery SOC but the EV congestion period. When the EV mode travel is compared with the SOC predicted value, If possible, the vehicle travels in the EV mode. If the SOC predicted value reaches the idle charge SOC, the vehicle travels in the EV mode to determine whether the vehicle can travel in the EV mode.

Conventionally, the engine ON time for charging the battery is determined by comparing the present battery SOC with the idle charging SOC or adjusting the EV line downward without considering the situation of the front road, and then downgrading the EV line.

The battery 42 is charged by the HSG 34 idle after the engine is started or the battery 42 is charged by the drive motor 33 in the state of engagement of the engine clutch 32 after the engine is started , Which resulted in unnecessary fuel consumption for battery charging and SOC management.

However, in the present invention, when the SOC predicted value of the EV mode during the congestion section reflecting the front road situation and the traffic condition is used, the EV mode travel is performed when the SOC is lower than the SOC of the idle charging but is higher than the SOC of the battery, SOC protection and management can be achieved, but the non-driving fuel loss can be effectively reduced.

4, since the vehicle travels in the EV mode during the stagnation period, it is possible to improve the fuel efficiency of the vehicle by reducing the loss of non-driving fuel by the engine 31, and after the stagnation section, Mode, the engine 31 is operated at an efficient operating point, and at the same time, the engine SOC is raised by charging the battery 42 by operating the drive motor 33 as a generator with engine power.

In the process of FIG. 3, when the existing SOC defense control entry condition is satisfied, a known SOC defense control step such as idle charging or EV line down control is performed.

In the present invention, the engine-on time is determined by using an adjusted EV line rather than an existing EV line, that is, an upward EV line compared to the existing EV line.

Upward adjustment of the EV line means adjusting the EV line so as to switch to the HEV mode at a higher variable condition, and the upwardly upgraded EV line has a value of " existing EV line + Can be expressed in the form.

An example of the EV line may be a boundary line connecting the vehicle speed at which the EV mode and the HEV mode are switched in the power map in which the required power is mapped according to the vehicle speed and the SOC, and the map value for each SOC.

At this time, the upward direction of the EV line may be a condition for switching from the EV mode to the HEV mode, that is, a power value for the vehicle speed at which the engine is started and a power value for each SOC are increased by?

The reason why the upwardly upgraded EV line is used is to satisfy the driver's demand by turning the engine on when the vehicle needs to accelerate after leaving the route guided by the navigation device by the driving operation of the driver.

When the driver unconditionally drives the EV, when the driver leaves the route guided by the navigation device, the driver can not adjust the required power by running on the EV at a high required power.

3, when the control unit receives a message informing that the vehicle has departed the route from the navigation device (S18), the control unit performs control according to the conventional method. If the vehicle is in the EV mode driving state in steps S14 and S17, So as to manage the battery SOC.

In this manner, in the battery SOC management method according to the present invention, after determining the forward congestion period using the navigation information, the SOC defense control is judged whether or not the SOC defense control is entered by predicting the SOC during the EV mode traveling in the congestion period.

In particular, it is possible to compare the SOC predicted value at the time of the EV mode running with the idle charging SOC to determine whether the EV mode can be traveled, and if possible, to travel in the EV mode so that the battery SOC can be maintained at a value higher than the idle charging SOC do.

Furthermore, if necessary, the SOC predicted value is compared with the minimum battery SOC to determine whether or not EV mode travel is feasible, and if possible, the vehicle travels in the EV mode so that the battery SOC can be maintained at a value higher than the battery use minimum SOC .

Accordingly, it is possible to obtain an effect of reducing the SOC, which is a criterion for the entry of the SOC defensive control, while protecting the battery, and it is possible to enlarge the EV running period without driving the engine, Fuel efficiency can be improved.

In addition, it is possible to reduce the engine noise because the engine can be driven in the EV mode as compared with repeating frequent engine on / off in a short period of time in a congestion section, and the engine can be turned on / It is possible to improve the driving performance because there is no sense of heterogeneity.

Also, if the vehicle travels in the EV mode as much as possible in the congestion section using the navigation information and then escapes the congestion section, the battery SOC can be increased by using an efficient operating point in the engine partial load mode.

Also, it is possible to increase the battery SOC by running the vehicle in the EV mode as much as possible in the congestion period, and then charging the vehicle after the vehicle arrives at the destination and the vehicle is stopped or parked (frequent engine on / off repetition is not required for a short period of time).

Or if the hybrid vehicle is a plug-in hybrid vehicle, if the battery is charged by using an external power source after arriving at the destination, it is possible to reduce the maintenance cost of the vehicle because the battery charging cost is lower than the fuel cost.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. And are also included in the scope of the present invention.

10: navigation device 20: control unit
31: engine 32: engine clutch
33: drive motor 34: HSG
41: Inverter 42: Battery

Claims (8)

Determining whether the front road is a congestion period by receiving information on a front road ahead of the vehicle on the driving route from the navigation device;
Estimating and determining an SOC change amount in the EV mode driving of the congestion section when it is determined that the control section is the congestion section;
Comparing the current battery SOC and the determined SOC change amount (DELTA SOC) with a predetermined SOC reference value, which is an SOC predicted value at the EV mode running time of the congestion section; And
And controlling the vehicle such that the control unit travels in an EV mode in a congestion period if the 'battery SOC -? SOC' is higher than the SOC reference value.
The method according to claim 1,
The information about the forward road includes an average vehicle speed, which is real-time traffic information,
Wherein the controller compares the average vehicle speed with a predetermined vehicle speed and determines that the front road is a congestion section if the average vehicle speed is equal to or lower than the set vehicle speed.
The method according to claim 1,
The information about the forward road includes an average vehicle speed, which is real-time traffic information,
Wherein the step of predicting and determining the amount of change in SOC at the time of driving the EV mode comprises:
Determining a distance of the congestion section, dividing the determined congestion section distance by the average vehicle speed, and calculating a time required for the vehicle to pass through the congestion section at an average vehicle speed;
Calculating traveling resistance when the vehicle travels in the congestion section based on the information about the forward road and pre-stored setting information;
Calculating travel energy while the vehicle passes through the stagnant region by multiplying the calculated travel resistance by time; And
And calculating an SOC change amount when the vehicle is traveling in the EV mode using the calculated travel energy and the battery total energy which is battery specific specification information.
The method of claim 3,
Wherein the SOC change amount during the EV mode running is obtained by dividing the travel energy by the total battery energy.
The method of claim 3,
Wherein the information about the forward road further includes a road inclination angle,
Wherein the running resistance is determined by a sum of an air resistance according to the average vehicle speed, a frictional resistance of the driving system according to the average vehicle speed, a rolling resistance due to friction between the tire and the road surface, and a tilt resistance according to the road inclination angle. A method for managing the battery SOC of a vehicle.
The method of claim 3,
Wherein the SOC reference value includes a first SOC reference value and a second SOC reference value set to a value lower than the first SOC reference value,
The controller compares the 'battery SOC -? SOC' with the first SOC reference value and if the 'battery SOC -? SOC' is below the first SOC reference value, the 'battery SOC -? SOC' Value of the battery SOC of the hybrid vehicle.
The method of claim 6,
Wherein the second SOC reference value is a battery usable minimum SOC determined by a value obtained by adding a margin value to a minimum SOC value determined as a specific value of a battery.
The method of claim 7,
Wherein the margin value is set to a battery SOC value corresponding to a power at which the starting generator can start the engine a predetermined number of times.

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