JPH0216344A - Decelerating energy recovery device for vehicle - Google Patents

Abstract

PURPOSE:To ensure a smooth decelerating feeling while keeping the electric energy recovery accompanied by a deceleration satisfactorily by gradually reducing the electric energy recovery of a charging generator used as both a starting electric motor and a generator according to the progress of the deceleration. CONSTITUTION:A charging generator M affording a rotating force to a crank shaft 3 in starting and also converting the torque of the crank shaft 3 to an electric power to charge a battery 15 in driving is provided near a fly-wheel 8 in an engine E. The charging generator M is driven and controlled through an inverter part 25 and a fixed coil 22 by a control unit 27, based on the detection signals from various sensors 30-36 for detecting the driving state of the engine E. In this case, the charging generator M is controlled by the control unit 27 so that the electric energy recovery at the initial of the deceleration is increased and then reduced according to the progress of the deceleration.

Description

[Detailed Description of the Invention] [Industrial Application Fields] The present invention includes a charging generator driven by an engine, and converts surplus energy of a vehicle into electrical energy by generating electricity with the charging generator during deceleration. This invention relates to a vehicle deceleration energy recovery device that recovers deceleration energy and improves fuel efficiency and braking effectiveness of the vehicle.

[Prior Art] Generators can generally be used as electric motors, but in light of this fact, a vehicle has been proposed in which a charging generator is used as a starting motor when starting the engine. For example, see Japanese Patent Publication No. 61-54949 and Japanese Patent Application Laid-open No. 61-61926). Such a charging generator includes a field coil for electromagnetizing the flywheel, which is usually made of ferromagnetic material, and a fixed coil arranged at a fixed part around the outer periphery of the flywheel and forming a three-phase structure. , convert the DC power supplied from the battery into three-phase AC power and supply it to the fixed coil, or
An inverter section is provided that switches whether or not to convert the three-phase alternating current ffL power generated in the fixed coil into direct power to charge the battery. When starting the engine, three-phase AC power is supplied from the inverter to the fixed coil to use the charging generator as a starting motor.
Does charging occur when the engine is running as specified? The U machine is used as a generator, and the three-phase AC power generated in the fixed coil is converted into DC power by the inverter section to charge the battery.

In a vehicle equipped with such a charging generator,
A vehicle has been proposed in which a charging generator generates electricity during deceleration, converting the vehicle's mechanical energy, which was previously discarded as surplus energy, into electrical energy and recovering it. This has the advantage of improving fuel efficiency and promoting braking of the vehicle during deceleration.

[Problems to be Solved by the Invention] However, in conventional vehicles equipped with the above-mentioned charging generator and designed to recover surplus energy during deceleration,
The amount of power generated during deceleration, that is, the energy recovery rate, is set to a constant value, or the amount of power generated is controlled according to the supply and demand of electrical energy, such as the state of charge of the battery and the electrical load. Therefore, although recovery of surplus energy is attempted, no particular consideration is given to the deceleration feeling link. For this reason, a sufficient sense of deceleration cannot be obtained at the beginning of deceleration when relatively high speed transfer is performed.
On the other hand, in the middle to final stages of deceleration, the feeling of deceleration is excessively enhanced, so there is a problem in that a good deceleration feeling cannot be obtained. Furthermore, the energy recovered by the charging generator, that is, the reverse torque, fluctuates depending on the state of demand and supply of electrical energy, so there is a problem that the deceleration feeling is not constant.

The present invention has been made in view of the above-mentioned conventional problems, and is equipped with a charging generator, and generates electricity with the charging generator during deceleration, thereby recovering surplus energy and reducing braking of the vehicle. To provide a deceleration energy recovery device for a vehicle capable of obtaining good deceleration feeling while effectively recovering surplus energy of the vehicle and improving fuel efficiency.

"Means for Solving the Problems" In order to achieve the object stated in item 1-, the present invention is provided with a charging generator driven by an engine, and the charging generator generates electricity during predetermined deceleration operation, so that the vehicle In a vehicle configured to recover mechanical surplus energy as electric energy, the charging generator is controlled so as to increase the energy recovery rate at the initial stage of deceleration and to decrease the energy recovery rate as deceleration progresses. A deceleration energy recovery device for a vehicle is provided, which is characterized by being provided with energy recovery rate control means.

[Operations and Effects of the Invention] According to the present invention, at the initial stage of deceleration, the energy recovery rate braking means increases the energy recovery rate of the charging generator, that is, the reverse torque, by increasing the field current, for example, Since the braking action of the vehicle is enhanced, it is possible to sufficiently recover the large mechanical surplus energy at high speeds, and to obtain a strong deceleration feeling that matches the deceleration feeling of the driver.

Since the energy recovery rate is reduced as deceleration progresses, the reverse torque is gradually weakened in the middle to final stages of deceleration, providing a smooth deceleration feeling that matches the driver's deceleration feeling. reactor. Therefore, it is possible to obtain a feeling of deceleration according to the speed of the vehicle while sufficiently recovering surplus energy, and to improve the feeling of deceleration.

[Example] Examples of the present invention will be specifically described below.

As shown in FIG. 1, the power plant PS of the vehicle burns intake air (air mixture) supplied through the intake passage l in accordance with the opening degree of the throttle valve 2, and uses the thermal energy to rotate the crankshaft 3. Engine E converts into energy,
Depending on the soft position of the engine lever 4, the crankshaft 3
a transmission T that shifts the torque and transmits it to drive wheels (not shown) via a propeller shaft 5, and a clutch device that disconnects transmission of torque from the crankshaft 3 to the transmission T when a clutch pedal 6 is depressed. It is composed of C.

When the clutch pedal 6 is not depressed, the clutch device C transmits the torque of the flywheel 8, which is coaxially fixed to the crankshaft 3 and rotates in addition to the crankshaft 3.
A clutch plate 11 that is brought into frictional engagement with the flywheel 8 by the compression of the pressure plate 9, and a clutch hub 13 spline-fitted to the main drive shaft 12, transmit the transmission to the main drive shaft 12 (clutch - When the clutch pedal 6 is depressed, the compression of the breathoyer plate 9 against the flywheel 8 side is stopped, the frictional engagement between the flywheel 8 and the clutch plate II is released, and the frictional engagement between the flywheel 8 and the clutch plate II is released. Torque is not transmitted to the main drive shaft 12 (clutch off).

By the way, inside and around the flywheel 8, a rotational force is applied to the crankshaft 3 when starting the engine E to start the engine E, and when the engine E is in a predetermined operating state, the crankshaft 3 is A charging generator IM is provided which charges the battery 15 by converting a part of the torque into electric power, and this charging generator M will be described below.

The flywheel 8 is formed of a ferromagnetic material, and a number of slots 16 are arranged annularly along the outer circumference of the flywheel 8 on the front surface of the flywheel 8, slightly inside the outer circumference of the flywheel 8. A magnetic coil I7 is installed. The field coils 17 are formed in a spiral shape with the radial direction of the flywheel 8 as an axis in each slot 16, and when these field coils 17 are energized, the field arranged in each slot 16 is At a position corresponding to the magnetic coil 17, an N or S ffl pole is formed on the outer periphery of the flywheel 8, and the flywheel 8 includes an electromagnet in which N poles and S poles are alternately arranged on the outer periphery. It is supposed to form. Field current is supplied to the field coil 17 through a field current supply conductor I8, and power is supplied to this first current supply conductor 18 from the battery 15 through a main current supply conductor I9. It is now possible to do so. Further, the strength of the field current is controlled by a field controller 21.

On the other hand, a fixed coil 22 is provided to form a rotating magnetic field around the flywheel 8, and the fixed coil 22 is formed in an annular shape on the outside of the outer periphery of the flywheel 8 in close proximity thereto. It is fixed to a ferromagnetic material zabota 23 fixed to the housing. The fixed coil 22 has a three-phase structure (U, V, W), and each of these phases (UV, W) is connected to the inverter section 25 through a fixed coil current supply conductor 24 having a three-phase structure.
Phase AC power is supplied, or conversely, three-phase AC power generated within the fixed coil 22 is supplied to the inverter section 25.

The two-legged inverter section 25 is an ordinary DC/AC converter composed of several power transistors (not shown), and turns on/off each power transistor according to a signal applied from the control unit 27. By setting the off state to a predetermined state, when the ignition switch 28 is turned on and the relay switch 26 is closed accordingly, the DC power supplied from the battery 15 through the main current supply conductor 19 is converted to three-phase AC power. or convert the three-phase AC power induced in the fixed coil 22 into a DC horn and supply it to the fixed coil 22 through the fixed coil current supply conductor 24.
5 to charge the battery 15.

Then, in response to a signal from the control unit 27, each power transistor of the inverter section 25 is configured such that the magnetic pole of the rotating magnetic field formed by the fixed coil 22 is retarded from the field pole of the corresponding flywheel 8. When set to generate a three-phase alternating current, the charging generator M acts as a generator, while the magnetic poles of the rotating magnetic field formed by the stationary coil 22 are closer than the corresponding field poles of the flywheel 8. When set to generate a three-phase alternating current that is formed on the advance side,
The charging generator M is adapted to act as an electric motor. Then, in response to a signal from the control unit 27, when starting the engine, the charging generator M acts as a starting motor to start the engine E. The battery 15 is charged by functioning as a generator.

In addition, when the vehicle decelerates, the charging generator M generates electricity, and the mechanical surplus energy of the vehicle is recovered as electrical energy, improving fuel efficiency and promoting braking of the vehicle. However, in order to improve the deceleration feeling, the control unit 27 intensifies the field current applied to the field coil 17 at the beginning of acceleration, increasing the amount of power generated by the charging generator M, that is, increasing the reverse torque. The speed has been increased to give a strong sense of deceleration. Then, as the deceleration progresses, the field current is reduced, the reverse torque is reduced, and the feeling of deceleration is gradually weakened to provide a smooth deceleration feeling.

The control unit 27 is a comprehensive control device including an energy recovery rate control means as described in the claims of the present application, and includes a throttle opening TVθ detected by a throttle opening sensor 31 and a throttle opening detected by a vehicle speed sensor 30. Vehicle speed V, idle switch signal detected by idle switch 32, crank angle (rotational speed N) detected by crank angle sensor 33 and amplified by amplifier 34, clutch switch signal detected by clutch switch 35, neutral switch 36
Predetermined control is performed using the neutral switch signal etc. detected by the controller as control information.Hereinafter, according to the flowchart shown in FIG. 2, the energy recovery rate of the charging generator M during deceleration related to the present application will be determined. Only the control method will be explained.

When control is started, step S! The vehicle speed V is read.

In step S2, the throttle opening degree TVθ is read, and the throttle valve opening/closing speed V is calculated using the following equation.

In the above formula, TVθ is the current throttle opening, and T
Vθ° is the previous throttle opening, and ΔL is the elapsed time.

In step S3, it is compared whether the throttle valve opening/closing speed V is negative, that is, whether a deceleration operation is in progress. As a result of the comparison, if v<O (YES), the deceleration operation has been started, so the control proceeds to step S4. The program then proceeds to S5, an energy recovery rate control routine during deceleration.

In step S4, the initial value i of the field current of the field coil 17 is
. is determined. In this embodiment, for example, as shown in FIG. 3, when deceleration starts at time t0 (v<0), a deceleration signal as shown by the polygonal line G1 is transmitted, and upon receiving this deceleration signal, the deceleration starts. The target value of the field current i of the field coil 17 is determined. As shown by the polygonal line G, the target value of the field electric field Ai is the initial value i when the deceleration signal is transmitted. It has a characteristic that after that, it decreases at a constant decreasing rate (Δi/Δt). And field current initial value i.

is set to a larger value when the closing speed of the throttle valve is large, that is, when the deceleration is large, in order to increase the braking effect.

In step S5, the rate of decrease of field current i with respect to time (
Δi/Δt) is determined. As described above, the target value of the field current i is the initial value i. The field current decreases at a constant rate (Δi/Δt) after the field current is set to The field current reduction rate (Δi/Δt), which is determined based on the speed -V and the vehicle speed V, is stored in the control unit 27 as a map. In step S5, the field current reduction rate (Δi/Δt) corresponding to the throttle valve closing speed -■ and the vehicle speed V is read from the map. In this way,
At the beginning of deceleration, the field current i is set to a high value of 10, so the amount of power generated by the charging generator M increases, the reverse torque increases, the vehicle is strongly braked, and a strong sense of deceleration is obtained. . On the other hand, in the middle to final stages of deceleration, the field current i decreases, so the amount of power generated by the charging generator M decreases, the reverse torque decreases, and the braking of the vehicle is gradually weakened, providing a smooth feeling of deceleration. It will be done.

After this, control returns to step S1 and continues.

On the other hand, as a result of the comparison in step S3, if ■≧0 (
No), since no deceleration operation has been performed, step S5. controls the energy recovery rate during deceleration. S6 is not executed, and control returns to step Sl and continues.

In this embodiment, the throttle valve opening/closing speed V and the vehicle speed V
The field current i may be controlled in more real time by using the rate of change in vehicle speed, rate of change in engine speed, whether or not the brake is activated, etc. as control information. .

[Brief explanation of the drawing]

FIG. 1 is a system configuration diagram of a power plant for a vehicle equipped with a deceleration energy recovery device according to the present invention. FIG. 2 is a flowchart showing a control method of energy recovery rate control during deceleration by the control unit. Figure 3 is a diagram showing the characteristics of the deceleration signal sent during deceleration and the field current control target value versus time. Figure 4 is a diagram showing the field current control with throttle valve closing speed and vehicle speed as independent variables. FIG. 3 is a diagram showing a map of target values. PS...Power plant, E...Engine, C...Clutch device, T...Transmission, M...Charging generator, 1...Intake passage, 2...Throttle valve, 3
... crankshaft, 6. clutch pedal, 8. flywheel, 1. battery, 17.. field coil,
21... Field controller, 22... Fixed coil, 2
5... Inverter L27... Control unit.

Claims (1)

[Claims] (1) Equipped with a charging generator driven by an engine,
In a vehicle that recovers the mechanical surplus energy of the vehicle as electrical energy by generating electricity with the charging generator during a prescribed deceleration operation, it increases the energy recovery rate at the initial stage of deceleration and increases the energy recovery rate as the deceleration progresses. A deceleration energy recovery device for a vehicle, comprising an energy recovery rate control means for controlling the charging generator to reduce the energy recovery rate.