JP3267658B2 - Engine alternator control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control mechanism for an alternator, which is an AC generator mounted on a vehicle.

[0002]

2. Description of the Related Art A vehicle is provided with an alternator which is an AC power generator. The rotation of the engine is transmitted to the alternator, and the rotor rotates to obtain a three-phase alternating current. Then, the three-phase alternating current is rectified by a rectifier into a direct current, and is charged into a battery mounted on the vehicle. The power generated by the rotation of the engine in this way is once stored in the battery,
It is mainly output for ignition, but is also used as appropriate for lighting, heating and others.

In the power supply system of such a vehicle, power is supplied to various parts via the battery as described above. Therefore, the state of charge of the battery is important and must be constantly monitored. Therefore, conventionally, the state of charge of the battery is confirmed by detecting the voltage, and when the detected voltage value is lower than a preset voltage set value, power generation by the alternator is executed. The generated power is supplied to the battery. When the battery voltage value is higher than the set value, power generation is not performed.

In addition, Japanese Patent Application Laid-Open No. Sho 59-22220 discloses, for example, a parallel circuit of a battery and an alternator for an electric power load, which controls an electric power supply system in a vehicle in relation to an alternator and a battery. Constitute
There is disclosed an apparatus in which alternator excitation is switched in accordance with an electric power load to control electric power supply, thereby improving power generation efficiency while eliminating instability of engine output.

Japanese Unexamined Patent Publication No. 60-298877 discloses a power generation restriction prohibiting means for prohibiting the power generation restriction by the alternator when the output voltage of the alternator is lower than a predetermined value. There is disclosed an apparatus in which a battery is prevented from being over-discharged by operating a restriction prohibiting means.

[0006]

In the conventional control of the electric power supply system in a vehicle, the set value of the battery charge to be compared for the control is only a predetermined point. It has been determined whether the alternator is operating or not operating on the basis of the set value, and power supply to and supply of power from the battery has been performed. This is described in Japanese Patent Application Laid-Open Nos. 59-2222099 and 60-22099.
The situation is the same for the one disclosed in Japanese Patent No. 298877.

However, in practice, depending on the value of the set value of the battery charge, it is not suitable to operate the alternator depending on the driving condition of the vehicle even if the set value is less than the predetermined value. In some cases, it may be more appropriate to operate the alternator depending on the driving condition of the vehicle even if the voltage value is equal to or higher than a predetermined set value.

However, in conventional power system control,
Since the operation control of the alternator with fine grain according to the driving condition of the vehicle as described above was not performed, for example, a high load was applied to the engine to deteriorate fuel efficiency,
There is a problem that a high torque is applied to a drive belt for driving the alternator, thereby shortening the life of the belt.

The present invention has been made in order to solve the above-mentioned problems, and an engine which improves fuel efficiency and extends the life of the drive belt by appropriately controlling the operation of the alternator. It is an object of the present invention to provide an alternator control device.

[0010]

According to a first aspect of the present invention, there is provided an alternator control device for an engine, wherein the battery is charged by receiving power from an alternator that operates and generates electric power in conjunction with the rotation of the engine, and that is set in advance. In an alternator control device for an engine provided with a control unit for controlling the operation or non-operation of the alternator in accordance with the voltage value of the battery, the battery has a voltage detection sensor for detecting the voltage value. provided, in the engine provided an engine speed sensor the rotational speed is detected, the said control unit and two voltage set value consisting of upper voltage setting value and the lower voltage setting value of the battery, alternator drive Rotation speed at which torque is maximum
A predetermined engine speed setting value exceeding the predetermined value is input in advance, and the voltage value of the battery detected by the voltage detection sensor and the engine speed detected by the engine speed sensor are input to the control unit. Composed,
From the control unit, when the voltage value of the battery is lower than the lower voltage set value, an operation signal is transmitted to the alternator, and when the battery voltage value is equal to or higher than the lower voltage set value and lower than the upper voltage set value . the engine speed operation signal on <br/> Symbol alternator is transmitted when more than the engine rotational speed setting value, of the battery
The voltage value is higher than the lower voltage setting value and the upper voltage setting
If the engine speed is less than the specified value and the engine speed is
If the value is less than the set value, the alternator
The alternator is configured to transmit a non-operation signal to the alternator when the transmitted voltage value is equal to or higher than the upper voltage set value.

According to a second aspect of the present invention, there is provided an alternator control apparatus for an engine according to the first aspect, wherein the control unit outputs a voltage value of the battery equal to or more than the lower voltage set value and When the engine speed is lower than the upper voltage set value, the engine speed is lower than the engine speed set value , and the external load used for purposes other than the vehicle running of the engine is small, the alternation
In this case, an operation signal is transmitted to the data in place of the non-operation signal .

[0012]

According to the alternator control device for an engine according to the first aspect of the present invention, when the voltage value of the battery is less than the lower voltage set value, an operation signal is transmitted from the control unit to the alternator. The alternator which receives it operates and generates electric power, and the battery is charged with the electric power.

When the voltage value of the battery is in the range between the upper and lower voltage set values, the alternator operates only when the engine speed is equal to or higher than the set value, that is, when the engine is rotating at some high speed. Power is generated and the battery is charged. On the other hand, when rotating at a certain low speed,
The engine does not operate and the engine load can be reduced.
And contribute to improved fuel efficiency.

When the voltage value of the battery is equal to or higher than the upper voltage set value, a non-operation signal is transmitted to the alternator. Therefore, in this case, the alternator does not operate and power is not supplied to the battery, so that overcharging of the battery is prevented.

According to the second aspect of the present invention, the control unit sends the battery voltage value equal to or higher than the lower voltage set value and lower than the upper voltage set value, and the engine speed is controlled by the engine speed. Less than the set value
Ri, external load small to be used in addition to the vehicle running of the engine
At this time , an operation signal is transmitted to the alternator. (Only this area is different from the control according to claim 1.) Therefore, even when the battery voltage value is within the range of the upper and lower voltage set values and the engine is rotating at low speed , Alternator if the above external load is small
Operates and generates electricity, and the battery is charged.

[0016]

FIG. 1 is a block diagram illustrating an alternator control device for an engine according to the present invention. As shown in FIG. 1, an alternator control device 1 mounted on a vehicle includes an alternator 2 that is a three-phase AC generator and a battery 3 that is charged by electric power supplied from the alternator 2.
And a control unit 4 for controlling the operation of the alternator 2.

The alternator 2 includes a three-phase stator 21 having a stator coil and a three-phase stator 21.
And a rotor 22 provided with a field coil that rotates in a space surrounded by. The rotor 22 is driven to rotate by rotation of an alternator pulley connected to a crankshaft of an engine (not shown) via a drive belt. Then, when the rotor 22 rotates, a three-phase alternating current is generated in the stator 21, and this power is rectified into DC power by a rectifier 23 including six diodes. The rectified DC power is output to the battery 3 in a state where the pulsation is leveled by the capacitor 24. A part of the three-phase alternating current is supplied to the rotor 22 after being rectified by an auxiliary rectifier (not shown ).

The stator 21 and the rotor 22
Is connected to a regulator 26 provided in the alternator 2. The regulator 26 is formed with a predetermined electric circuit in which various transistors, resistors, or diodes are incorporated, and an operation signal is transmitted from the control unit 4 to the regulator 26 while the rotor 22 is rotating. When the rotor 22 is energized according to the signal, power is generated, and when the energization to the rotor 22 is stopped in response to the non-operation signal, the rotor 22 is rotating. Power generation is not performed. Therefore, even when the rotor 22 is rotating in the non-power generation state, the rotational torque is negligibly small.

The battery 3 is provided with a voltage detection sensor 31 composed of a voltmeter.
Is input to the control unit 4 as a battery voltage.

On the other hand, an engine (not shown) is provided with an engine speed sensor 5 for detecting the speed. Engine speed (N) detected by this speed sensor 5
Are input to the control unit 4 one by one.

An external load O (not shown) for the engine (specifically, an air conditioner or the like) is applied to the engine.
An N / OFF detection sensor 6 is provided, and an ON / OFF signal detected by the external load ON / OFF detection sensor 6 is configured to be input to the control unit 4 one by one.

The control unit 4 is supplied with an upper voltage set value (V1) and a lower voltage set value (V2) for a battery in advance. In this embodiment, 13.5 volts is adopted as the upper voltage set value (V1), and 12.3 volts is adopted as the lower voltage set value (V2). The upper voltage set value (V1) is a voltage value indicating that the battery 3 is charged to its full capacity, and when the battery 3 is at this voltage value, more power is supplied to it. Even so, it is not overcharged and stored. On the other hand, the lower voltage set value (V2) is set so that the vehicle normally performs its function.
At least this level is a voltage value comparable to the amount of charge that would be required. The lower voltage set value (V2) is about 90% of the upper voltage set value (V1).

Further, an engine speed set value (N1) for the engine speed is input to the control unit 4 in advance. In the present embodiment, the value of the engine speed setting value (N1) is 1500 rpm. This 1500 rpm corresponds to the rotation speed of the alternator pulley of 3000 rpm.

Then, the value of the battery voltage of the battery 3 detected by the voltage detection sensor 31, the engine rotation speed (N) detected by the rotation speed detection sensor 5, and the external load ON / OF
In accordance with the external load signal detected by the F detection sensor 6, each value is compared with the above upper voltage set value (V1), lower voltage set value (V2), and engine speed set value (N1), and the comparison result And the ON / OFF state of the external load signal.
Is operated (a state in which the alternator 2 performs power generation) or non-operation (a state in which the alternator 2 does not generate power) is transmitted to the regulator 26.

Hereinafter, a first example of alternator control according to the present invention will be described with reference to FIG. FIG. 2 is a flowchart showing a control flow of a first example of alternator control. As shown in this figure, first, in step S1, a battery voltage (V), an engine speed (N), and an external load ON / OFF signal are input to the control unit 4.

Then, in the next steps S2 and S3, the battery voltage (V) is compared with the upper voltage set value (V1) and the lower voltage set value (V2). Based on these comparisons, the battery voltage (V) is set to the higher voltage set value (V
1) If it is equal to or more than 1, the process branches to step S6 at once, and this step is executed, and the non-operation signal of the alternator 2 is transmitted from the control unit 4 to the regulator 26, so that the alternator 2 does not generate power. Therefore, the battery 3 is not charged.

When the battery voltage (V) is lower than the lower voltage set value (V2), an operation signal is transmitted to the regulator 26 in the alternator 2 unconditionally. Since the internal circuit is switched to the power generation circuit, the alternator 2 generates power, and the battery 3 is supplied with power and charged.

When the battery voltage (V) is higher than the upper voltage set value (V
If it is less than 1) and not less than the lower voltage set value (V2), the next step S4 is executed, and the engine speed (N) is compared with the engine speed set value (N1). When the engine speed (N) is equal to or greater than the engine speed set value (N1), step S5 is executed, the alternator 2 generates power as described above, and the battery 3 is charged.

FIG. 3 is a graph showing an example of the relationship between the rotation speed of the alternator and the consumed horsepower, drive torque or output current. In this graph,
Even when the engine speed (N) is equal to or less than 1500 rpm (that is, the alternator rotation speed is 3000 rpm), the alternator 2 is operating and generating power. As shown in this graph, the driving torque of the rotating shaft of the alternator rotor 22 is such that the rotating speed is 2000
rpm until it reaches 2000 rpm.
Indicates the maximum value, and thereafter gradually decreases as the rotation speed increases.

The consumed horsepower consumed when the alternator 2 is operated (the product of the driving torque value and the rotation speed) sharply increases until the rotation speed reaches 3000 rpm. Indicates a gradually increasing trend.

Further, the electric current generated by the alternator 2 sharply increases until the rotation speed reaches 3000 rpm, but thereafter (especially 5000 rpm).
Above) shows a substantially constant value.

From the above, the operation of the alternator 2 is 300
At 0 rpm or less, it is unstable, and the generated current value is small despite the need for a large drive torque.

In the present invention, when the battery voltage (V) is between the upper voltage set value (V1) and the lower voltage set value (V2), that is, whether the alternator 2 performs power generation is selected. In the region, the engine speed (N) is equal to the engine speed set value (N1) (in this embodiment, N1 = 1500 rpm, the alternator rotation speed 300).
If not more than 0 rpm, the alternator 2 does not operate, and the drive torque of the alternator pulley does not become the value shown in the graph of FIG. 3 (no torque is generated because it is not involved in power generation). Therefore, an excessive force is not applied to the drive belt for driving the alternator 2, and the life of the belt can be extended.

A second example of alternator control according to the present invention will be described with reference to FIG. FIG. 4 is a flowchart showing a control flow of a second example of alternator control.
In this second example, step S4 'is set below step S4 of the first example.

That is, when the engine speed (N) is smaller than the engine speed set value (N1) in step S4,
In step S4 ', whether the external load is ON or not
It is asked if it is FF.

When the external load is ON, step S
6 is executed and the alternator 2 does not generate power, so that the battery 3 is not charged. However, when the external load is OFF in step S4 ', step S5 is executed, and power is generated in the alternator 2, so that the battery 3 is charged.

With this arrangement, when the engine speed (N) is less than the engine speed setting value (N1), the alternator 2 is not operated when an external load such as an air conditioner is ON, so that the load on the engine is reduced. And contribute to improvement of fuel efficiency.

[0038]

As described above, according to the alternator control apparatus for an engine of the present invention, the control unit constituting this control mechanism has two voltage set values including an upper voltage set value and a lower voltage set value of a battery. , Alternator
A predetermined engine speed setting value exceeding the rotation speed at which the driving torque is maximized is input in advance, and the voltage value of the battery detected by the voltage detection sensor and the engine speed detected by the engine speed sensor are determined by the control unit. It is configured to be inputted to. When the voltage value of the battery is lower than the lower voltage set value, an operation signal is transmitted from the control unit to the alternator.
The alternator that has received it operates to generate electricity, and the battery is charged with the electric power, so that the so-called dead battery can be effectively prevented.

When the battery voltage value is equal to or higher than the lower voltage set value and lower than the upper voltage set value, an operation signal is transmitted to the alternator only when the engine speed is equal to or higher than the engine speed set value. You. Therefore, when the battery voltage value is in the range between the upper and lower voltage set values, the engine speed is equal to or higher than the set value, that is, from when the drive belt is rotating at a high speed to some extent where the torque becomes small. Since the alternator operates, excessive torque is not applied to the drive belt, and the life of the drive belt can be extended correspondingly.

Further, when the battery voltage value is equal to or higher than the upper voltage set value, a non-operation signal is transmitted to the alternator. Therefore, in this case, the alternator does not operate,
Since no power is supplied to the battery, useless overcharging of the battery is prevented.

[0041] In addition to the above control, the voltage value of the battery is less than the above lower voltage set value or more and the upper voltage set value, the engine speed is less than the engine rotational speed setting value, other than a vehicle traveling further engine When the external load used for
Operation signal instead of non-operation signal
If this happens, the alternator will operate in that area,
The battery is charged.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an alternator control device for an engine according to the present invention.

FIG. 2 is a flowchart illustrating a first example of alternator control according to the present invention.

FIG. 3 is a graph illustrating an example of a relationship between a rotation speed of an alternator and a consumed horsepower, a driving torque or an output current.

FIG. 4 is a flowchart illustrating a second example of alternator control according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Alternator control apparatus 2 Alternator 21 Stator 22 Rotor 23 Rectifier 24 Capacitor 26 Regulator 3 Battery 31 Voltage detection sensor 4 Control unit 5 Rotation speed detection sensor 6 External load ON / OFF detection sensor N Engine rotation speed N1 Engine rotation speed setting value V Battery voltage V1 Upper voltage setting value V2 Lower voltage setting value

Claims (2)

(57) [Claims] A battery is charged by receiving power from an alternator that operates and generates electric power in conjunction with rotation of an engine, and the operation or non-operation of the alternator is set according to a predetermined battery voltage value. In the alternator control device for an engine provided with a control unit for controlling the engine as described above, the battery is provided with a voltage detection sensor for detecting a voltage value thereof, and the engine is provided with an engine speed detection sensor for detecting a speed. The control unit is provided with two voltage set values including an upper voltage set value and a lower voltage set value of the battery ;
A predetermined engine speed setting value exceeding the rotation speed at which the driving torque of the motor becomes the maximum is input in advance, and the voltage value of the battery detected by the voltage detection sensor and the engine rotation speed detected by the engine speed sensor are Is configured to be input to the control unit.When the voltage value of the battery is lower than the lower voltage set value, an operation signal is transmitted to the alternator from the control unit, and the voltage value of the battery is set to less than the lower voltage set value or more and the upper voltage set value, the engine speed is operating signal to the alternator is transmitted when more than the engine rotational speed setting value, the voltage value of the low voltage of said battery
Above the set value and below the upper voltage set value,
When the gin speed is less than the engine speed set value
Nonworking signal is transmitted to the alternator, the alternator control of the engine where the voltage value of the battery is characterized in that when more than the upper voltage setpoint is configured to inoperative signals to the alternator is transmitted apparatus. 2. An alternator for an engine according to claim 1.
In the control device, when the voltage value of the battery is equal to or higher than the lower voltage set value and lower than the upper voltage set value, the engine speed is lower than the engine speed set value , and above alternator when the external load is small to be used in addition
An alternator control device for an engine, wherein an operation signal is transmitted instead of a non-operation signal .