KR20090111175A - Engine clutch control system for hybrid electric vehicle and method thereof - Google Patents

Abstract

PURPOSE: An engine clutch control system for hybrid electric vehicle and a method for the same are provided, which improve marketability of the hybrid vehicle by providing stable shift feeling and riding comfort. CONSTITUTION: An engine clutch control system for hybrid electric vehicle comprises an engine(80) and a motor(100) which assists the output torque of the engine; an engine clutch(90) which is arranged between the engine and motor; and a TCU(30) which controls the up/down shift of a transmission; and an HCU/MCU(60) which controls the engine clutch by determining the control input according to the request of TCU.

Description

ENGINE CLUTCH CONTROL SYSTEM FOR HYBRID ELECTRIC VEHICLE AND METHOD THEREOF}

The present invention relates to a hybrid vehicle to which an engine clutch is applied, and more particularly, to an engine clutch control apparatus and method for a hybrid vehicle that improves a feeling of shifting by slip-controlling an engine clutch when an up / down shift is performed to a target shift stage. will be.

The hybrid vehicle is driven by an engine that operates as a main power source and a battery, and a motor that assists the main power source is applied to operate the fuel economy with the highest driving conditions.

The hybrid vehicle is operated in hybrid mode in oscillation / acceleration and climbing which put a heavy load on the engine so that the motor assists the output torque of the engine.

However, in the constant speed driving, the engine is operated in the engine mode or the hybrid mode to travel at the sum of the output torque of the engine or the output torque of the engine and the motor.

Hybrid vehicles are typically equipped with an automatic transmission (hereinafter referred to as a "transmission") in accordance with the driver's demand for convenience of driving.

In the hybrid vehicle, when braking control by the brake pedal is performed while driving, the motor assisting the engine power enters the regenerative braking mode (REGENERATION) and is converted into a generator, thereby recovering the deceleration energy and charging the battery.

In recent years, hybrid vehicles are equipped with an engine clutch that regulates the output torque of the engine between the engine and the motor instead of the torque converter in order to reduce cost and minimize torque loss transmitted to the transmission.

Therefore, when the hybrid vehicle is operated in the engine mode has a power transmission structure of the engine + engine clutch + transmission + drive wheels, when the hybrid vehicle is operated in the hybrid mode has a power transmission structure of the engine + engine clutch + motor + transmission + drive wheels, and the motor mode When operated as a power transmission structure of the motor + transmission + drive wheels.

The hybrid vehicle to which the engine clutch is applied is engaged with the engine clutch when the shift of the up shift or the down shift is performed according to the vehicle speed and the throttle opening in the engine mode or the hybrid mode. The shift to the target shift stage is executed.

Therefore, a shift shock, which was absorbable in the torque converter, is transmitted to the vehicle as it is, thereby causing a problem of deterioration of the shift feeling, thereby lowering the riding comfort.

The present invention has been invented to solve the above problems, and its object is to provide a stable shift feeling and ride comfort by slip-controlling the engine clutch when an up / down shift occurs while the hybrid vehicle is operated in the engine mode or the hybrid mode. It is.

An engine clutch control apparatus for a hybrid vehicle according to a feature of the present invention for realizing the above object includes a motor for assisting the engine and the output torque of the engine; An engine clutch disposed between the engine and the motor; It includes a TCU to control the up / down shift of the transmission,

And a HCU / MCU for slip controlling the engine clutch by determining a control amount according to the request of the TCU.

In addition, the engine clutch control method of a hybrid vehicle according to a feature of the present invention,

In the engine mode or the hybrid mode, the TCU determines whether an up / down shift request is detected;

Requesting the HCU / MCU to slip control the engine clutch when a shift request is detected;

The HCU / MCU includes a process of determining the target hydraulic pressure and slip control of the engine clutch in the process of shifting by the TCU.

According to the above configuration, the present invention is expected to provide a stable shifting and riding comfort in up / down shifting of a hybrid vehicle to which an engine clutch is applied, thereby improving the merchandise of the hybrid vehicle.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention.

Since the present invention can be implemented in various different forms, the present invention is not limited to the exemplary embodiments described herein, and parts not related to the description are omitted in the drawings in order to clearly describe the present invention.

1 is a block diagram illustrating an engine clutch control apparatus of a hybrid vehicle according to an exemplary embodiment of the present invention.

The hybrid vehicle includes a driving request detector 10, an ECU 20, a TCU 30, a battery 40, a BMS 50, an HCU / MCU 60, an inverter 70, an engine 80, an engine clutch ( 90, the motor 100, the transmission 110, and the driving wheel 120.

The driving request detection unit 10 detects a driver's request signal including an APS (Accel Position Sensor) displacement, a throttle valve displacement, and a brake pedal displacement, which is a driving request of the driver, and outputs information about the driver's request signal.

The ECU 20 controls the overall operation of the engine 80 according to the request of the HCU / MCU 60, which is the host controller.

The TCU 30 controls the gear ratio of the transmission 110 by determining a target gear shift stage for up / down according to the current vehicle speed and the displacement of the throttle valve, and when the target gear shift stage is determined, the upper controller HCU / MCU (60). ), The slip control of the engine clutch 90 is requested.

The battery 40 supplies an operating voltage to the motor 100 in the hybrid mode and the motor mode, and is charged with the regenerative energy recovered through the motor 100 in the regenerative braking mode by brake braking.

The BMS 50 comprehensively detects information such as voltage, current, and temperature of the battery 40 to manage and control a state of charge (SOC) state and a charge / discharge current amount.

The HCU / MCU 60 controls the overall behavior of the vehicle by controlling the output torques of the engine 80 and the motor 100 by integrally controlling the respective controllers according to the driving demand of the driver and the state information of the vehicle.

When the HCU / MCU 60 requests slip control of the engine clutch 90 from the TCU 30, the HCU / MCU 60 determines the oil pressure for the target slip control and controls the oil pressure to control the engine clutch 90 with a current corresponding to the oil pressure. The solenoid is actuated to slip the engine clutch 90.

Inverter 70 is an Insulated Gate Bipolar Transistor (IGBT) switch element, and converts a DC voltage of the battery 40 into a three-phase AC voltage according to a pulse width modulation (PWM) control signal applied from the HCU / MCU 60. To drive the motor 100.

The output of the engine 80 is controlled by the control of the ECU 20 under the control of the HCU / MCU 60, which is an upper controller, and the amount of intake air is adjusted through an electric throttle control (ETC) not shown.

The engine clutch 90 is disposed between the engine 80 and the motor 100, and in the hybrid mode, the output torque of the engine 80 and the output torque of the motor 100 are added to the transmission 110.

The motor 100 is driven by the voltage of the battery 40 applied through the inverter 70.

Transmission ratio is adjusted according to the control of the TCU (30) is adjusted, the total torque applied through the clutch 90 is distributed to the synchronous transmission gear ratio to transmit to the driving wheel 120 to drive the car To help.

Since the general control operation in the hybrid vehicle according to the present invention including the function as described above is made the same or similar, the description of the operation thereof will be omitted.

The present invention is an invention for securing a shift feeling at the time of shift control in an engine mode or a hybrid mode, and only this will be described.

When the hybrid vehicle is operated in the engine mode, the output torque of the engine 80 is transmitted to the transmission 110 through the engine clutch 90. When the hybrid vehicle is operated in the hybrid mode, the output torque of the engine 80 and the output of the motor 100 are transmitted. The torque is summed through the engine clutch 90 and transmitted to the transmission 110.

As described above, the hybrid vehicle is operated in the engine mode or the hybrid mode, and the output torques of the engine 80 and the motor 100 are controlled according to the integrated control of the HCU / MCU 60, which is the uppermost controller. In the traveling state, the TCU 30 determines whether an up / down shift request is detected by various driving conditions including the vehicle speed and the displacement of the throttle valve.

When the up / down shift request is detected by the TCU 30, the target shift stage is determined, and then a duty control signal is output to the transmission 110 to shift the target shift stage.

At this time, the TCU 30 requests the HCU / MCU 60 to control the slip of the engine clutch 90 when the target gear shift stage for up / down shift is determined.

Accordingly, the HCU / MCU 60 determines the hydraulic pressure for the target slip control according to the request of the TCU 30, and the determined hydraulic pressure in the state in which the up / down shift is performed by the TCU 30 to the target shift stage. The corresponding current is output to the hydraulic control solenoid which operates the engine clutch 90.

Therefore, the slip of the engine clutch 90 is controlled by the TCU 30 in the process of performing the up / down shift to the target shift stage by the TCU 30 so that a stable shift in which shift shock is not generated in the up / down shift is achieved. Is executed.

2 is a diagram illustrating slip control of an engine clutch in an up shift condition of a hybrid vehicle according to an exemplary embodiment of the present invention.

When the slip request of the engine clutch 90 is detected by the HCU / MCU 60 (SS), the hydraulic pressure for the target slip control is determined, and when the set time t1 elapses, the hydraulic control solenoid is operated with a current rising to the determined hydraulic pressure. Operate.

Accordingly, the engine clutch 90 slips at an inclination S1 corresponding to the determined hydraulic pressure, and the target slip determined by the rotation speed N _E of the engine 80 versus the rotation speed N _T of the transmission 110. The rate S _tg1 is reached.

When the engine clutch 90 is controlled at the target slip ratio S _tg1 and the upshift execution SB is detected at the target shift stage, the engine clutch 90 is set to the set slope S2 after the set constant time t2. Slip control to maintain the target slip ratio (S _tgt2 ) in the shifting process.

Therefore, in the process of performing the upshift to the target shift stage, the influence of the engine clutch is eliminated, and the upshift in which the shift shock is not generated is executed.

When the synchronization point SYR of the target shift stage is reached, the slip ratio is released at the set slope S3 after a predetermined time t3, and the engine clutch 90 is completely engaged at the shift completion time SF. The output torque of 80 is allowed to be applied to the transmission 110 without loss.

3 is a diagram illustrating slip control of an engine clutch in a down shift condition of a hybrid vehicle according to an exemplary embodiment of the present invention.

Since the downshift operation is performed in the same manner as or similar to the above-described operation of the upshift, the operation of slip-controlling the engine clutch with the target flow rate in the process of shifting or downshifting under conditions opposite to the upshift is omitted. .

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It is included in the scope of rights.

1 is a view showing an engine clutch control apparatus of a hybrid vehicle according to an embodiment of the present invention.

2 is a timing diagram illustrating a control procedure of an engine clutch during upshift in a hybrid vehicle according to an exemplary embodiment of the present invention.

3 is a timing diagram illustrating a control procedure of an engine clutch during downshift in a hybrid vehicle according to an exemplary embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

30: TCU 60: HCU / MCU

80: engine 90: engine clutch

Claims (4)

An engine; A motor assisting the output torque of the engine; An engine clutch disposed between the engine and the motor; It includes a TCU to control the up / down shift of the transmission, Engine clutch control apparatus for a hybrid vehicle comprising a HCU / MCU to slip control the engine clutch by determining the control amount in accordance with the request of the TCU. The method of claim 1, The HCU / MCU is an engine clutch control apparatus of a hybrid vehicle for controlling the amount of slip by controlling the current applied to the hydraulic control solenoid provided in the engine clutch in accordance with the target slip amount. In the engine mode or the hybrid mode, the TCU determines whether an up / down shift request is detected; Requesting the HCU / MCU to slip control the engine clutch when a shift request is detected; The HCU / MCU determines a target hydraulic pressure and slip-controls the engine clutch in the process of shifting by the TCU; Engine clutch control method of a hybrid vehicle comprising a. The method of claim 3, The slip control of the engine clutch is controlled by the inclination set to reach the target slip ratio according to the start of the shift, and when the shift synchronization is completed, the slip ratio is released by the set inclination, and the engine clutch is completely coupled when the shift is completed. How to control engine clutch.

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