KR20050023135A - A driving system of vehicle and controlling method thereof - Google Patents

Abstract

PURPOSE: A driving system and a control method thereof of a vehicle are provided to increase use efficiency of an alternator by keeping two-wheel and four-wheel drive operations with one alternator, to cut down the cost, and to facilitate controls by removing one alternator. CONSTITUTION: A driving system of a vehicle is composed of an engine(101) generating power; a transmission(102) for converting power transmitted from the engine into a gear ratio set at a shift lever and driving front wheels(103); an air conditioner compressor(105) for compressing coolant circulated in driving an air conditioner system by receiving the power of the engine through a belt(104); an alternator(106) connected with the engine by the belt to generate voltage by power of the engine sent through the belt; a motor(110) driven in a four-wheel drive mode to drive rear wheels by a differential gear(112); a DC/DC(Direct Current) converter(107) for supplying power fed from the alternator to a battery(108) as charging voltage after decreasing down the power; a control unit(114) for controlling two-wheel and four-wheel drive operations, outputting target voltage and current by detecting information and the current of the voltage of the alternator for a four-wheel drive mode, and controlling the amount of the current of the alternator by calculating an exciting current order value; and a switching unit(109) for intermitting voltage passing between the alternator and the motor by a control signal of the control unit according to the four-wheel and two-wheel drive modes.

Description

A DRIVING SYSTEM OF VEHICLE AND CONTROLLING METHOD THEREOF

The present invention relates to a driving system of a vehicle, and more particularly, to power an electric load and a battery with one large-capacity alternator in a vehicle to which the electric 4WD driving scheme is applied, and driving power to the motor in the 4WD driving mode ( The present invention relates to a drive system of a vehicle and a control method thereof for supplying power, thereby involving efficient power control.

As can be seen in the accompanying FIG. 4, the conventional automobile to which the electric 4WD driving system is applied, converts the engine 11, which is the power source, and the power transmitted from the engine 11 to a set gear ratio, so that the vehicle runs. The transmission 12 transmits power to the 13, the engine 11 is connected to the belt 14, and a predetermined voltage is generated by the power of the engine 11 transmitted through the belt 14 to generate a battery. A small-capacity alternator 15 which supplies charging power to the electric power and supplies electric power to each electric load, and is connected to the engine 11 and the belt 14 to the power of the engine 11 transmitted through the belt 14. A large voltage alternator 16 for generating a predetermined voltage and supplying power to the motor 17 that drives the rear wheel 20 in the four-wheel drive mode, and a gear coupled to the rotating shaft of the motor 17. Power of the motor 17 transmitted through the 18 to the rear wheel 20 is transmitted And a 4WD controller 21 for controlling the amount of power generation of the large-capacity alternator 16 and the drive torque and speed of the motor 17.

The small-capacity alternator 15 for supplying power to each electric load and the battery provided in the vehicle and the large-capacity alternator 16 for supplying power to the motor 17 in the 4WD driving mode include a belt with the engine 11. 14) Independent operation by connection.

A vehicle to which the conventional electric 4WD drive system as described above is applied is controlled as follows.

When the road surface condition of the road is good and the driving of the flat place where a heavy load is not applied to the vehicle, the driving of the vehicle is maintained by two-wheel front wheel driving using the power of the engine 11 alone.

That is, when the power output from the engine 11 is transmitted to the transmission 12, the transmission 12 converts the power of the engine 11 into a set gear ratio to drive the front wheels 13 connected to the output shaft of the vehicle. Keep driving running

At this time, the small-capacity alternator 15 generates a predetermined voltage set by the power of the engine 11 transmitted through the belt 14 to supply power to each electric load provided in the vehicle and to supply the battery with a charging voltage. do.

In addition, the large-capacity alternator 16 is powered by the belt 14, but the power of the engine 14 is transmitted, but a power interruption is performed by a clutch means (not shown), so that the driving of the rotor is blocked, so that the large-capacity alternator 16 generates power. It won't work.

In this way, when the vehicle starts to run on the slippery road surface such as a steep slope or a rainy road or a snowy road in the state of maintaining driving by two-wheel all-wheel drive, the 4WD control unit 21 has a large capacity. By controlling the clutch means of the alternator 16 so that the large-capacity alternator 16 is driven by the power of the engine 11, the set voltage is generated, and the driving power is supplied to the motor 17 side.

Therefore, the motor 17 is driven by the power supplied from the large-capacity alternator 16, so that the rear wheel 20 is also simultaneously driven through the differential gear 19 to perform four-wheel drive.

At this time, the 4WD controller 21 controls the drive torque and speed of the motor 17 according to the rotational speed of the differential gear 19 for driving the rear wheel 20, and detects the output current generated in the large-capacity alternator 16 By controlling the excitation current, the control of the amount of generated current according to the capacity of the large-capacity alternator 16 is performed.

As described above, in the conventional vehicle to which the electric 4WD driving system is applied, the large-capacity alternator does not generate power in the driving state by the front wheels, and when driving or starting slippery roads such as hilly slopes, rainy roads or snow roads, etc. Since only the required voltage is generated, the section operating in the 4WD mode is very short, and there is an extremely inefficient use of a large-capacity alternator in terms of the system.

In addition, there is a problem that the production cost of the vehicle is increased due to the installation of a high-capacity high-capacity alternator that is inefficient in utilization, and the weight is increased to reduce fuel economy.

The present invention has been invented to solve the above problems, the purpose of which is to drive the rear wheel in the power and battery charging power and 4WD driving mode for the electric load with one large alternator in the vehicle to which the electric 4WD driving method is applied Power can be supplied to the motor for efficient power control.

In other words, it combines the functions of a small-capacity alternator, which is responsible for the operating power of the electric load and the charging power of the battery, and a large-capacity alternator that supplies power to the motor in the 4WD driving mode, to expand the operation range of the alternator for efficient utilization and Power control is performed.

In addition, the mechanical air conditioner compressor can be installed in the place where the small-capacity alternator is removed to provide convenience and efficiency to the installation of the air conditioner compressor without a separate engine design.

The present invention for realizing the above object is an engine that is a power source; A transmission that converts the power transmitted from the engine into a gear ratio set by a shift lever and drives the front wheels to drive the vehicle; An air conditioner compressor receiving power of the engine through a belt and compressing a refrigerant circulated when the air conditioner system is driven; An alternator connected to the engine and a belt, the alternator generating a voltage by the power of the engine transmitted through the belt; A motor driven in the 4WD driving mode to drive the rear wheel through the differential gear; A DC / DC converter for supplying a battery with a charging voltage by turning down the power supplied from the alternator; It controls two-wheel drive and 4WD drive, and detects current of generator voltage and general information of vehicle in 4WD drive mode and calculates excitation current command value so that target voltage and current can be outputted. Control means for controlling; And a switching unit for controlling a voltage path between the alternator and the motor in accordance with the 4WD driving mode and the 2WD driving mode by the control signal of the control means.

The method may further include determining a current driving mode; Determining whether the charging voltage of the battery is lower than or equal to a set reference voltage when it is determined that the driving mode is 2WD; The process of maintaining the current operating state that maintains the alternator off state when the charging voltage of the battery is above the set reference voltage, and charging the battery by generating an excitation current command to the alternator when the charging voltage is below the set reference voltage. and; Determining whether the battery voltage charged by power generation of the alternator is greater than or equal to a set reference voltage; Maintaining the charging through the alternator if the charging voltage of the battery is lower than the reference voltage, and turning off the alternator voltage generation if the charging voltage is higher than the reference voltage. To provide.

The method may further include determining a current driving mode; Determining whether to maintain the reference voltage by comparing the charging voltage of the battery and the set reference voltage to determine whether the 4WD operation is possible when the 4WD operation mode is determined; Connecting a power supply path between the alternator and the motor when the charging voltage of the battery is equal to or greater than the set reference voltage; Generating an excitation current command for driving the motor and performing voltage generation through the alternator; The present invention provides a method for controlling a driving system of a vehicle, comprising: driving a motor by using a generator voltage of an alternator to perform 4WD driving.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

As can be seen in Figure 1, the drive system of the vehicle according to the present invention is the engine 101, the transmission 102, the front wheel 103, the belt 104, the air conditioner compressor 105, the alternator 106 , A DC / DC converter 107, a battery 108, a switching unit 109, a motor 110, a gear 111, a differential gear 112, a rear wheel 113, and a four-wheel controller 114.

The engine 101 adjusts the speed of the vehicle by controlling the rotation speed according to the position change of the accelerator pedal driven by the driver as a power source.

The transmission 102 converts the power transmitted from the engine 101 into a gear ratio set by the shift lever and transmits power to the front wheels 103 so that the vehicle travels.

The air conditioner compressor 105 is connected to the engine 101 and the belt 104 and compresses the refrigerant circulated when the air conditioner system is driven by the power of the engine 101 transmitted through the belt 104.

The alternator 105 is connected to the engine 101 and the belt 104 and generates a predetermined voltage by the power of the engine 101 transmitted through the belt 104 to supply power to each electric load and a battery. .

The alternator 105 consists of a large capacity alternator.

The DC / DC converter 107 turns down the power supplied from the alternator 106 and supplies the battery 108 with the charging voltage.

The battery 108 is charged by the power generation voltage of the alternator 106 supplied through the DC / DC converter 107 to share the load power required for each electrical load.

The switching unit 109 is switched by a control signal applied from the 4WD controller 114 to supply the power generation voltage supplied from the alternator 106 to the motor 110 in the 4WD driving mode, and is turned off in the two-wheel driving mode. The power supply voltage of the alternator 106 is blocked from being supplied to the motor 110 side.

The motor 110 is composed of a three-phase DC motor, and is driven in the 4WD driving mode to drive the rear wheel 113 through the differential gear 113.

The gear 111 is connected to the rotating shaft of the motor 110 and is responsible for transmitting the power of the motor 110 to the differential gear 112.

The 4WD controller 114 controls two-wheel drive and 4WD driving, and detects the current of the alternator 106 in the 4WD driving mode and calculates an excitation current command value of the alternator 106 so that the target voltage and current can be output. PWM duty control.

In addition, the drive torque and speed of the motor 110 are controlled by detecting the output rotation speed of the differential gear 112.

The operation of the driving system of the vehicle according to the present invention having the above configuration will be described with reference to FIG. 2 as follows.

When the road surface and the weather conditions of the road is good, the driving of the flat place without a lot of load on the car 4WD controller 114 blocks the contact of the switching unit 109 power path between the alternator 106 and the motor 110 By blocking the driving of the vehicle by the two-wheel front wheel drive through the power of the engine 101 alone.

That is, when the power output from the engine 101 is transmitted to the transmission 102, the transmission 102 converts the power of the engine 101 to the gear ratio set by the selection of the shift lever, and the front wheel 103 connected to the output shaft. By driving the driving of the car is maintained.

When the air conditioning system is turned on, the air conditioner compressor 105 compresses the refrigerant circulated by the power of the engine 101 transmitted through the belt 104 and compresses the refrigerant to high pressure and high temperature.

In addition, the 4WD controller 114 monitors the voltage state of the battery 108 to determine whether the voltage of the battery 108 falls below the set reference voltage, and the voltage of the battery 108 falls below the reference voltage. If detected, an excitation current command is outputted to the alternator 106 side so that power generation is performed.

Accordingly, the alternator 106 generates a predetermined voltage set by the power of the engine 101 transmitted through the belt 14 and supplies the charged voltage to the battery 108 through the DC / DC converter 107.

In the process of charging the battery 108 through the voltage generation of the alternator 106 as described above, if the voltage monitored by the 4WD controller 114 is detected to be higher than the set reference voltage and determines that the overcharge state, the output of the excitation current command is blocked. This prevents voltage generation of the alternator 106 from occurring.

As such, when the vehicle starts to operate in the four-wheel drive mode during the initial start and operation of slippery roads such as hilly slopes, rain roads or snowy roads, the 4WD controller 114 is alternator. An excitation current command is output to the 106 to generate power, and at the same time, the contact point of the switching unit 109 is turned on to connect the power supply path between the alternator 106 and the motor 110.

Accordingly, the motor 110 is driven by the power generation voltage supplied from the alternator 106 to allow 4WD driving to drive the rear wheel 113 through the differential gear 112.

At this time, the 4WD control unit 114 monitors the information on the throttle opening degree and the information on the engine speed from the engine control module 101A connected through the CAN communication server, and the speed stage currently selected from the transmission control unit 102A. Monitor information about the motor, the rotational speed of the motor 110 and the temperature of the brush, and the wheels of the front wheel 103 and rear wheel 113 from the ABS control unit 103A of the front wheel 103 and rear wheel 103 Monitor the speed.

In addition, the current output from the alternator 106 is monitored.

Then, the 4WD control unit 114 calculates the vehicle speed from the speed of the front and rear wheels in the monitored information, and calculates the drive torque of the motor 110 for the displacement information of the vehicle speed and the accelerator pedal position.

Then, the current for calculating the target torque is calculated in consideration of the motor rotational speed, and the current command value of the alternator 106 for outputting the target voltage and the current is calculated in consideration of the current of the alternator 106 which is detected by the feedback, and the alternator The amount of power generation of 106 is controlled.

The above operation relationship will be described in detail with reference to FIG. 3 as follows.

When the driving of the vehicle to which the electric 4WD driving system is applied is performed, the 4WD controller 114 determines whether the current driving state is the 2WD or 4WD mode (S101).

In the above determination, if it is determined that the vehicle is in the two-wheel all-wheel mode, the voltage of the battery 108 is monitored to determine whether the current charging voltage V.bat is a set reference voltage, preferably 13.8 V or less ( S102).

If it is determined that the charge voltage V.bat of the battery 108 maintains the set reference voltage or more, the current state is maintained, and if it is determined that the charge voltage V.bat is less than the set reference voltage, DC / DC The converter 107 is turned on to connect the power supply path between the alternator 106 and the battery 108 (S103), and simultaneously outputs an excitation current command to the alternator 106 as a PWM signal to the alternator 106. Voltage generation is performed (S104).

Accordingly, voltage charging is performed on the battery 108 through the DC / DC converter 107 in accordance with the voltage generation by the alternator 106.

As described above, whether or not the charging voltage V.bat of the battery 108 is set to a reference voltage, preferably 13.8 V or more, in the state where the voltage of the battery 108 is generated by the development of the alternator 106. It is determined (S105).

If the charging voltage (V.bat) of the battery 108 is maintained below the set reference voltage in the determination of S105 to return to the process of S104 to continue charging the battery 108, the battery 108 If it is determined that the charging voltage of the full charge exceeds the set reference voltage, the excitation current command of the alternator 106 is output to be off so that the voltage generating operation of the alternator 106 is no longer performed (S106). The DC converter 107 is turned off to cut off the voltage path between the alternator 106 and the battery 108 (S107).

In addition, if it is determined in S101 that the vehicle is currently driven in the 4WD mode, whether the voltage V.bat charged in the battery 108 is maintained below the set reference voltage to determine whether the 4WD can be driven. Determine (S110).

If it is determined that the charging voltage of the battery 108 is maintained below the set reference voltage, the process proceeds to the above-described step S103 and repeats the above-described process to maintain the charging voltage of the battery 108 at the set reference voltage, and then 4WD. To allow the traveling of the vehicle to be performed.

However, when it is determined that the charging voltage of the battery 108 is maintained above the set reference voltage, the switching unit 109 is turned on to connect the power supply path between the alternator 106 and the motor 110 to generate an excitation current command. By controlling the voltage generation of the alternator 106, 4WD driving is performed (S111).

As described above, the present invention increases the use efficiency of the alternator by maintaining 2WD and 4WD driving by using one alternator, and provides cost reduction, control simplicity, and light weight of the vehicle by eliminating one alternator.

1 is a schematic configuration diagram of a drive system of a vehicle according to the present invention.

Figure 2 is a detailed block diagram of a drive system for a vehicle according to the present invention.

3 is a flowchart of an embodiment of power generation control in a drive system of a vehicle according to the present invention;

4 is a schematic configuration diagram of an electric four wheel drive system in a conventional vehicle.

Claims (11)

An engine which is a power generating source; A transmission that converts the power transmitted from the engine into a gear ratio set by a shift lever and drives the front wheels to drive the vehicle; An air conditioner compressor receiving power of the engine through a belt and compressing a refrigerant circulated when the air conditioner system is driven; An alternator connected to the engine and a belt, the alternator generating a voltage by the power of the engine transmitted through the belt; A motor driven in the 4WD driving mode to drive the rear wheel through the differential gear; A DC / DC converter for supplying a battery with a charging voltage by turning down the power supplied from the alternator; It controls two-wheel drive and 4WD drive, and detects current of generator voltage and general information of vehicle in 4WD drive mode and calculates excitation current command value so that target voltage and current can be outputted. Control means for controlling; And a switching unit for interrupting a voltage path between the alternator and the motor in accordance with a 4WD driving mode and a 2WD driving mode according to a control signal of the control means. The method of claim 1, The alternator is a drive system for a vehicle, characterized in that for applying a large-capacity alternator. The method of claim 1, The control means for controlling the power generation of the alternator according to the state of the charge voltage of the battery when driving in the 2WD mode, the drive system of the vehicle, characterized in that to perform the voltage charging of the battery. The method of claim 1, The control means for driving the vehicle 4WD mode, characterized in that for driving the 4WD mode after charging the battery charging voltage of the battery above the set reference value when the charging voltage of the battery is less than the set reference voltage. The method of claim 1, The control means monitors the wheel speed of the front and rear wheels, the generator current of the alternator, the engine speed, the throttle opening degree, and the shift stage selection information of the shift lever during operation in the 4WD mode, and outputs a target voltage and current from the monitored information. And generating and controlling an alternator current command value to be used. The method of claim 5, The control means calculates the vehicle speed from the wheel speeds of the monitored front and rear wheels, calculates the motor torque from the displacement of the vehicle speed and the accelerator pedal, calculates the amount of current for calculating the target torque in consideration of the motor rotational speed, And a current command value for outputting a target voltage and current, including information on the amount of generated current. In a vehicle to which the electric 4WD drive system is applied, Determining a current driving mode; Determining whether the charging voltage of the battery is lower than or equal to a set reference voltage when it is determined that the driving mode is 2WD; The process of maintaining the current operating state that maintains the alternator off state when the charging voltage of the battery is above the set reference voltage, and charging the battery by generating an excitation current command to the alternator when the charging voltage is below the set reference voltage. and; Determining whether the battery voltage charged by power generation of the alternator is greater than or equal to a set reference voltage; Maintaining the charging through the alternator if the charging voltage of the battery is lower than the reference voltage, and turning off the alternator voltage generation if the charging voltage is higher than the reference voltage. . In a vehicle to which the electric 4WD drive system is applied, Determining a current driving mode; Determining whether to maintain the reference voltage by comparing the charging voltage of the battery and the set reference voltage to determine whether the 4WD operation is possible when the 4WD operation mode is determined; Connecting a power supply path between the alternator and the motor when the charging voltage of the battery is equal to or greater than the set reference voltage; Generating an excitation current command for driving the motor and performing voltage generation through the alternator; A method of controlling a drive system for a vehicle, comprising: driving a motor by using a power generator voltage of an alternator to perform 4WD driving. The method of claim 8, If the charging voltage of the battery is less than the reference voltage in the 4WD driving mode, the drive system control method of the vehicle characterized in that the driving voltage in the 4WD mode after maintaining the charging voltage of the battery above the reference voltage through the generation of alternator. The method of claim 8, And a large voltage generated by the alternator during voltage charging of the battery is down by the DC / DC converter and supplied as a charging voltage. The method of claim 8, In the 4WD operation mode, the alternator generation current includes information on a target torque calculated by the vehicle speed of the front and rear wheels monitored, displacement of the accelerator pedal, a target torque calculated by the number of motor revolutions, and an alternator generation amount of the detected alternator, in which the target voltage and current are controlled. A control method for a drive system of a vehicle, characterized in that.