KR20110051979A - Control method for preventing slipping of hybrid electric vehicles - Google Patents

Abstract

PURPOSE: A method for preventing slipping of a hybrid vehicle is provided to actively control by reflecting the position of a shift lever. CONSTITUTION: A method for controlling slipping of hybrid vehicle comprises: a step of determining stop state of the vehicle; a step of determining that the slope angle of the lane is over the predetermined range of the slope angle; a step of determining the positive slope or negative slope in case that the slope angle of the lane is over the predetermined range of the slop lane; and a step of controlling the operation of a creeping aid system.

Description

Control method for preventing slipping of hybrid electric vehicles}

The present invention relates to a rolling prevention control method when driving on a slope, and more particularly, to a rolling prevention control method for preventing a hybrid vehicle from being pushed upon restarting after an idle stop on a slope.

A hybrid vehicle means an efficient combination of two or more different power sources to drive a vehicle, but in most cases, an engine that burns fuel (fossil fuel such as gasoline) to obtain torque and an electric motor that obtains torque by battery power Means a vehicle driven by, it is commonly referred to as a hybrid electric vehicle (HEV).

This hybrid vehicle is a future vehicle that can improve fuel efficiency and reduce emissions by adopting not only an engine but also an electric motor as an auxiliary power source. Is going on.

The hybrid vehicle is a pure electric vehicle (EV) mode using only the power of the electric motor (drive motor), a hybrid electric vehicle (HEV) mode using the rotational power of the driving motor as an auxiliary power while the rotational power of the engine is the main power, When driving by braking or inertia of vehicle, braking and inertia energy is recovered through generation of driving motor and driving in regenerative braking (RB) mode.

In this way, the mechanical energy of the engine and the electrical energy of the battery are used together, and the optimum operating area of the engine and the driving motor is used as well as the energy is recovered by the driving motor during braking, thereby improving fuel efficiency of the vehicle and making efficient use of energy.

Meanwhile, in a hybrid vehicle, a transmission having a clutch does not transmit power when the clutch between the engine and the transmission is open when the brake is on, and when the brake is off, the clutch is engaged. Transmits power.

However, when the vehicle is restarted after stopping while driving on a slope (climbing road), the vehicle is pushed backward when sufficient power is not transmitted to the wheel at the time of restarting after the brake off.

A typical hybrid vehicle has an idle stop function to turn off the engine when stopping to improve fuel efficiency and reduce exhaust gas. The idle stop function operates even when the vehicle is stopped while driving on a ramp, and the engine stops while driving on a ramp. Is off.

The vehicle is started by the driver's intention to restart at the idle stop, that is, the brake off, which takes about 1 to 2 seconds to increase the engine speed to complete the start of the engine and to engage the CVT clutch. This can lead to a large amount of rolling of the vehicle due to insufficient power being transmitted to the wheel during this time.

In order to solve the above problems, the hybrid vehicle is provided with a rolling prevention device, that is, a CAS (Creeping Aid System) to prevent the vehicle from rolling after stopping, the accompanying Figure 1 is a configuration of the CAS system of the hybrid vehicle It is shown.

If the driver presses the brake pedal (1) on the slope and satisfies the predetermined operating condition after the brake pedal switch is turned on (brake on), the brake hydraulic pressure is maintained for a predetermined time by turning on the CAS for a predetermined time (brake device By the vehicle braking state is maintained) to prevent the vehicle from rolling.

Here, the vehicle control unit (HCU) 2 determines the inclination / flat based on the output signal of the inclination angle sensor and operates the CAS (CAS On) / CAS (Off), wherein the inclination angle is set in advance. Determining the inclination outside the inclination angle range (CAS is off the inclination angle range, for example, -3 ~ 3 °) to turn on the CAS.

In this case, in the CAS, the ABS hydraulic valve 3 is operated by a control signal (CAS Valve On Request) of the vehicle controller to fix the vehicle.

Normally, the vehicle controller receives various signals according to the vehicle status, that is, the vehicle speed, engine speed, brake pedal switch signal, and inclination angle sensor signal, receives a brake on signal, and the vehicle speed and engine speed decrease to stop the vehicle. In determining the Idle stop entry, if the slope (forward slope / sub-tilt) / flat (low slope or flat within the inclination angle range) is determined based on the inclination angle sensor signal, the slope is out of the set inclination angle range Activate the CAS.

However, the conventional anti-skid device (CAS) did not reflect the driver's driving intention because only the inclination angle is used in determining whether the CAS is on / off after determining the slope / level.

Accordingly, the present invention has been invented in consideration of the above-described matters, and in determining and controlling whether the casing prevention device (CAS) is in operation (CAS On) / off (CAS Off), the shift lever which is the driver's driving operation state It is an object of the invention to enable the active control that is actively reflected the driver's will on the ramp by further reflecting the position of the.

In order to achieve the above object, the present invention includes the steps of determining whether the stopped road is out of the set inclination angle range from the signal of the inclination angle sensor after determining that the vehicle is in a stopped state; Determining an inclined road slope or an inclined road slope in a steel plate path in a state outside the set inclination angle range; According to the present invention, there is provided a method of controlling a rolling prevention of a hybrid vehicle, the method including controlling the operation of the rolling prevention device according to the position of the shift lever in the state of determining the inclined or sub-tilt.

In a preferred embodiment, in the step of controlling the operation of the anti-skid device, when the position of the shift lever is the D or L stage, the anti-skid device is operated if the forward slope, and if the sub-tilt is released to the release state Keep it.

In addition, in the step of controlling the operation of the anti-rolling device, when the position of the shift lever is the R-slope if the inclined device is operated, if the inclined slope, the operation of the anti-roller device is kept in a released state.

In the case where it is determined that the vehicle is in the stopped state outside the set inclination angle range, when the shift lever is in the P stage, the operation of the anti-skid device is kept in a released state.

In addition, when it is determined that the vehicle is out of the inclination angle range set in the stopped state, when the position of the shift lever reaches N steps in the state in which the idle stop is released, the operation of the skid prevention device is maintained in a released state.

Accordingly, the above-described problem solving means has the following effects.

In the present invention, by controlling the operation of the skid prevention device by reflecting the position of the shift lever of the driver's driving operation state active control can be made to actively reflect the driver's will on the slope.

For example, from the position of the shift lever and the signal of the inclination angle sensor, the road inclination angle is negative and the shift lever is positioned in the D and L stages or in the normal position, such as the case of the R stage. If is unnecessary, active control that reflects the driver's intention, such as deactivation of the skid prevention device, becomes possible.

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.

2 is a block diagram illustrating a signal input state of a control unit (CAS control unit) and a rolling prevention device (CAS) provided in a vehicle controller (HCU) according to the present invention, and FIG. It is a figure which shows the state in which a rolling prevention device is controlled.

In addition, Figure 4 is a view showing the release condition of the anti-rolling device in the shift lever position D stage and R stage in the present invention, Figure 5 is a flow chart showing a control method according to the present invention.

According to the present invention, the position of the shift lever, which is the operation state of the driver's shift lever, is determined in determining and controlling the condition (CAS On) / CAS Off of the skid prevention device (hereinafter referred to as CAS) when driving on a slope of a hybrid vehicle. The additional focus is on active control that reflects the driver's will on the ramp.

Hereinafter, in the present specification, the operation or on of the CAS is applied to the brake hydraulic valve so that the vehicle is prevented from being pushed into a braked state in which the vehicle is fixed by the brake device. The braking state by the brake device is released by releasing the hydraulic pressure of the brake hydraulic valve.

First, referring to FIG. 2, the control unit receives a vehicle speed, a shift lever position, an idle stop state signal, and an inclination angle sensor signal to determine a CAS on / off condition based on the result, and control CAS on / off according to the determination result. It shows that the control signal (CAS Valve On / Off Request) is outputted.

At this time, in the CAS, the operation of the hydraulic valve (ABS hydraulic valve / CAS valve) of the brake device is controlled by the control signal output from the control unit. For example, the control signal (CAS Valve On Request) output from the control unit determining the CAS on condition is controlled. As a result, the hydraulic valve is operated (valve on) to fix the vehicle in a braking state in which the hydraulic pressure is prevented from being pushed.

On the contrary, the operation and the braking state of the hydraulic valve are released (valve off and hydraulic release) by a control signal (CAS Valve Off Request) output from the control unit determining the CAS off condition.

In addition, the control unit basically receives the vehicle speed to determine whether the vehicle is stopped on the road, and receives the shift lever position signal to determine the driver's shift lever operation state.

In addition, the controller is a control element for controlling the on / off of the CAS based on a signal input in the vehicle controller (HCU), in the hybrid vehicle, the vehicle controller determines the idle stop and release conditions according to the driving state of the vehicle This is the highest level controller that controls the entry / release of the stop.

In response, the controller receives an idle stop state signal in the vehicle controller to recognize whether the vehicle is currently in the idle stop state or the idle stop state is released.

In addition, the controller receives a signal of the inclination angle sensor and determines the inclination / low inclination based on the signal. If the inclination angle is within a set inclination angle range (for example, -3 to 3 °) from the signal of the inclination angle sensor, the CAS is determined. It is determined by the low inclination (including flat) to be turned off, and when the inclination angle is out of the preset inclination angle range, the inclination path is determined.

In particular, the control unit is determined by judging the positive inclination and the sub-tilt (see Fig. 3) out of the inclination angle range from the signal of the inclination angle sensor, the inclination and sub-inclination outside the inclination angle range, the operating state of the shift lever which is the driver's will Therefore, the control to turn off or on the CAS is performed.

That is, when the control unit determines the low inclination within the inclination angle range, the vehicle is in a stopped state, but the vehicle will not be pushed, so naturally, the CAS is turned off. Even when the inclination is determined, control is performed to turn off the CAS in accordance with the position of the shift lever.

For example, as shown in FIG. 3, when the position of the shift lever is at the R stage while the vehicle is stopped, the CAS is turned off at the positive slope outside the inclination angle range. Turn off CAS.

In the present specification, the inclined slope refers to a case in which the inclined path is out of the inclination angle range (eg, inclined angle exceeding 3 °), and the inclined slope is inclined while out of the inclination angle range. Refers to the case where is a steel sheet furnace (e.g., a state of inclination angle less than -3 °).

In addition, in the present specification, the low inclination refers to a state within the inclination angle range of the road, and it is understood that it includes a flat land.

Figure 4 shows the low inclination conditions under which the operation of the CAS is released (off), and the inclination angle conditions under which the operation of the CAS is released in the D stage (same L stage) and R stage, the inclination angle of the low inclination in which the operation of CAS is released An example is shown with the range set at -3 to 3 °.

Of course, the low inclination condition of -3 to 3 ° is an example of setting a low inclination range including flat land where the rolling does not occur even without brake braking.

In FIG. 4, when the position of the shift lever operated by the driver in the sub slope outside the low slope range is D, the operation of the CAS is turned off. The sub slope is a ramp in which the vehicle can be pushed out of the low slope range. In the case of stage D and L, the CAS is turned off at the sub slope because the driving direction of the vehicle is the direction of the driver's driving will.

In addition, when the position of the shift lever operated by the driver at the R slope is out of the low slope range, the operation of CAS is turned off. The slope is a ramp in which the vehicle can move out of the low slope range. In the case of the forward slope, since the vehicle's driving direction is the driver's driving direction, the CAS is turned off.

In addition, as shown in Fig. 3, when the driver operates the shift lever in the P-stage, the driver's will stops on the inclined road (positive slope / sub-tilt), so that the idle stop is released and the CAS is off.

In addition, when the driver operates the shift lever in the N-stage, the driver's will stops on the inclined road (forward slope / subtilt), so that the operation of the CAS is controlled on / off depending on whether or not the idle stop is performed. That is, the CAS is turned off when the idle stop is released, and the CAS is turned on when the idle stop is entered.

Hereinafter, with reference to the accompanying Figure 5 describes the anti-roll control method according to the present invention.

In the present invention, the driver's will is actively reflected by controlling the on / off of the CAS according to the inclination angle, the position of the shift lever, and the idle stop while the vehicle is stopped, so that the CAS does not operate under particularly unnecessary conditions.

First, the controller determines that the vehicle is stopped from the vehicle speed signal (S10). If the controller determines that the currently stopped road is a low slope or a plain (eg, within -3 to 3 °) from the inclination angle sensor signal, CAS is determined. Keep it off (S11).

In addition, if the inclination angle is out of the low inclination state (that is, the positive inclination or the sub inclination) while the vehicle is stopped and the position of the shift lever is operated by the driver in the P stage, the CAS is kept in the off state (S12).

On the other hand, after determining the inclination angle range of the low inclination (that is, in the normal inclination or sub-inclination), the CAS is turned on if the position of the shift lever is not in the P stage but in the idle stop entry state (S13).

However, when the idle stop is not in the idle stop state, that is, when the position of the shift lever is N-stage while the idle stop is released (S14), the CAS is kept off (S14).

On the other hand, the positive slope or the sub-tilt is discriminated, and when the shift lever is at the R stage, the CAS is turned on when the sub-tilt is inclined, and the CAS is kept off when the tilt is inclined (S15 and S16).

Also, the positive slope or the sub-tilt is discriminated, and when the shift lever is at the D- or L-stage, the CAS is kept off if the tilt is negative, and the CAS is turned on (S17).

In this way, in the present invention, the control state of the shift lever by the driver is further reflected in the on / off control of the CAS, so that active control reflecting the driver's will can be achieved.

The embodiments of the present invention have been described in detail above, but the scope of the present invention is not limited to the above-described embodiments, and various modifications of those skilled in the art using the basic concepts of the present invention defined in the following claims and Improved forms are also included in the scope of the present invention.

1 is a configuration diagram of a CAS system of a hybrid vehicle.

FIG. 2 is a block diagram illustrating a signal input state of a control unit and a casing prevention device (CAS) provided in a vehicle controller (HCU) according to the present invention.

3 is a view showing a state in which the anti-rolling device is controlled in accordance with the position of the shift lever in the present invention.

4 is a view showing a release condition of the slide preventing device in the shift lever position D stage and R stage in the present invention.

5 is a flowchart illustrating a control method according to the present invention.

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

3: brake hydraulic valve 10: vehicle controller (HCU)

11 control unit 20 CAS (anti-rolling device)

Claims (5)

Determining whether the stopped road is out of a set inclination angle range after determining that the vehicle is in a stopped state; Determining an inclined road slope or an inclined road slope in a steel plate path in a state outside the set inclination angle range; Controlling the operation of the skid prevention device according to the position of the shift lever in the state of determining the inclined or sub-tilt; Anti-roll control method of a hybrid vehicle comprising a. The method according to claim 1, In the step of controlling the operation of the anti-rolling device, when the position of the shift lever is the D-stage or L-stage, the anti-skid device is operated, if the sub-tilt is characterized in that the operation of the anti-skid device is maintained in the released state Anti-roll control method of a hybrid vehicle. The method according to claim 1, In the step of controlling the operation of the anti-rolling device, when the position of the shift lever is the R-slope if the inclined device to operate the anti-tilt, if the forward tilting hybrid, characterized in that to maintain the operation of the anti-roller Vehicle anti-roll control method. The method according to claim 1, And determining that the shift lever is in the P-stage when the vehicle is in a stopped state when the vehicle is stopped. If the position of the shift lever is P, the operation of the skid prevention device is maintained in a released state. The method according to claim 1, When the vehicle is in a stopped state and is determined to be out of the set inclination angle range, when the position of the shift lever reaches N steps in the state where the idle stop is released, the operation of the skid prevention device is maintained in a released state. Anti-roll control method.

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