JPH05270330A - Power device for vehicle - Google Patents

Abstract

PURPOSE:To provide such a unit as capable of supplying a power to the load concerned even in case of a malfunction of a generator. CONSTITUTION:This power device is provided with an engine 2 to be mounted on a vehicle and a generating set generating a high rated voltage with this engine as a driving source. This generating set consists of a hydraulic system 10 and an alternator 1. A blower motor 3 and a voltage converter 20 are connected to this alternator 1. This voltage converter 20 consists of a first converter for conversion from high voltage to the low one and a second converter from the low voltage to the high, and either of then is selected. A 12V battery 5 to be charged by the output of this voltage converter 20 is connected to an output terminal at the low voltage side of this voltage converter 20, and further a headlamp 6 is connected to the output terminal of this 12V battery 5. A malfunction detector 13 detects something wrong with the alternator 1, and selects the second converter at the time of malfunction detection.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle power supply device. In particular, it relates to one having a high rated voltage power source and a low rated voltage power source.

[0002]

2. Description of the Related Art Recently, there is an increasing number of loads mounted on a vehicle that have a higher operating efficiency when operated by supplying a higher voltage. A power supply device that supplies electric power to such a load will be described with reference to FIG.

Reference numeral 1 is a DC output alternator having a rated voltage of 48 V, and has a built-in voltage regulator. The alternator 1 generates electric power by rotating through the output shaft of the engine 2, the pulley and the belt. The alternator 1 generates a voltage of about 60 V between the terminals of the alternator 1 in order to supply a voltage of 48 V to the load 3 described later.

Reference numeral 3 is a blower motor (high-voltage side load) of an air conditioner, which is connected via a switch 7.
When the driver or passenger operates the switch 7 and the switch 7 is closed, 48 V of electric power generated by the alternator 1 is supplied to operate.

Reference numeral 4 is a voltage converter, which is composed of a semiconductor of one chip, and which outputs the voltage of 48 V generated by the alternator 1.
Convert to a voltage of 12V.

Reference numeral 5 is a battery having a rated voltage of 12 V, and the voltage of 48 V generated by the alternator 1 is converted into a voltage of 12 V by the voltage converter 4 and charged.

Reference numeral 6 denotes a headlamp (low-voltage side load), which operates by being supplied with 12V of power from the output of the voltage converter 4 via the switch 8. The headlamp 6 supplies 12V of power because the filament of the lamp may burn out when a high voltage of 48V is applied. The headlamp 6 is usually the alternator 1
The voltage of 48V generated by is converted into the voltage of 12V by the voltage converter 4, and the voltage of 12V is applied to operate.
When sufficient electric power cannot be supplied by the electric power from the alternator 1, electric power is also supplied from the 12V battery 5.

As described above, the alternator 1 charges the 12V battery 5 and supplies the electric power to the headlamp 6 through the blower motor 3 and the voltage converter 4.

[0009]

However, in such a vehicle power supply device, since the power supply to the blower motor (high voltage side load) is configured to be performed only by the alternator, an abnormality in the engine or the alternator may occur. If it occurs and the alternator does not operate normally, power cannot be supplied to the high-voltage side load such as the blower motor, and the high-voltage side load such as the blower motor stops, which may reduce the comfort of the vehicle. was there.

It is an object of the present invention to provide a vehicle power supply device capable of supplying electric power to a high voltage side load even when the alternator does not operate normally.

[0011]

The structure of the present invention will be described with reference to the claim correspondence diagram shown in FIG.

First, the first invention will be described.

Reference numeral 2 denotes an engine mounted on a vehicle, and a generator 50 that uses this engine 2 as a drive source to generate a high rated voltage.
Are connected.

The output terminal of the generator 50 has a first load 3
Are connected.

Further, 5 is a low-voltage secondary battery, and a second load 6 is connected to the output terminal of this low-voltage secondary battery 5.

Reference numeral 20 denotes a voltage converter having a first terminal 15 connected to the output terminal of the generator 50 and a second terminal 16 connected to the low voltage secondary battery 5, The first voltage converting means 17 for converting the voltage input to the terminal 15 into a low voltage and outputting it to the second terminal, and the voltage input to the second terminal 16 to a high voltage for converting the first voltage Second voltage conversion means for outputting to terminal 15
And 18 to switch from the first voltage conversion means 17 to the second voltage conversion means 18 when the first signal is input.

Numeral 13 is an abnormality detecting means, which detects an abnormality of the generator 50, and when this abnormality is detected, outputs a first signal to the voltage converter 20.

In the second invention, the generator 50 of the first invention is rotated by the engine 2 as a drive source,
The drive means 10 outputs a constant rotation regardless of the engine speed, and the alternator generates a high rated voltage at a constant rotation by the output of the drive means 10.

[0019]

Since the vehicular power supply device has the above-described structure,
Normally, the high voltage generated by the generator 50 is converted into a low voltage by the first voltage conversion means 17 of the voltage conversion means 20 and supplied to the second load 6.

When the abnormality detecting means 13 detects that an abnormality has occurred in the generator 50, the second voltage converting means 18 of the voltage converter 20 converts the low voltage to the high voltage, and the low voltage The electric power of the secondary battery 5 is converted into the first load, converted from the low voltage to the high voltage by the voltage converter 20, and supplied to the second load.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS.

First, the configuration will be described with reference to FIG.

Reference numeral 2 is an engine provided in a vehicle or the like, and a hydraulic device 10 (which will be described in detail later) is rotated by this engine 2. Reference numeral 1 is a DC output alternator having a rated voltage of 48V, and the alternator 1 rotates by the rotation of the hydraulic device 10 to generate electricity. The alternator 1 generates a voltage of about 60 V between the terminals of the alternator 1 in order to supply a voltage of 48 V to the load 3 described later. The alternator 1 and the hydraulic device 10 are defined as a power generator 50.

Reference numeral 3 denotes a blower motor for an air conditioner, which is operated via a switch 7. When the driver or a passenger operates the switch 7 and the switch 7 is closed, 48 V of electric power generated by the alternator 1 is supplied. It works.

Reference numeral 20 is a voltage converter for converting a voltage of 48V to 12V
The first converter 17 to convert the voltage of 12V to 48V
It is composed of a second converter 18 for converting to a V voltage and relays 15 and 16 for switching the conversion direction, which will be described in detail later.

Reference numeral 5 is a battery having a rated voltage of 12V, and the voltage of 20V generated by the alternator 1 is converted into a voltage of 12V by the voltage converter 20 and charged.

Reference numeral 6 denotes a headlamp which operates by being supplied with 12V of electric power from the output of the voltage converter 20 via the switch 8. This headlamp 6 has a filament
When a high voltage of 48V is applied, it may burn out, and it supplies 12V of power. Also, this headlamp 6 is usually generated by the alternator 1.
The voltage of V is converted into the voltage of 12V by the voltage converter 20, and the voltage of 12V
When the power from the alternator 1 alone cannot supply sufficient power, the
Electric power is also supplied from the V battery 5.

Reference numeral 13 denotes an abnormality detecting device. The abnormality detecting device 13 includes a discharge flow rate signal 11 indicating a discharge flow rate Q of the hydraulic device 10.
And an engine speed signal 12 indicating the engine speed N of the engine 2.
Is input and the input / output switching signal 14 is output to the voltage converter 20 according to the discharge flow rate signal 11 and the engine speed signal 12.

Reference numeral 21 is a display device. When the abnormality detection device 13 outputs the input / output switching signal 14 to the voltage converter 20, the display signal 22 is input to the display device 21 and the current 12V battery 5 remains. A future running distance and running time are calculated by an arithmetic unit (not shown) from the usage statuses of the capacity and the load, and the distance and time are displayed.

Next, the hydraulic device 10 will be described with reference to FIG.

The hydraulic pump 25 is connected to the engine 2,
The oil in the oil pan 27 is pumped up by the rotation of the engine 2, and the oil is supplied to the hydraulic motor 26. The supplied oil rotates the hydraulic motor 26, and this rotation causes the alternator 1 to rotate to generate electric power. The oil supplied to the hydraulic motor 26 is again discharged to the oil pan 27 when the hydraulic motor 26 is rotated.

At this time, as shown in FIG. 4, when the rotation speed N of the engine 2 becomes a constant value b or more, the discharge flow rate Q of the oil discharged from the hydraulic pump 25 to the hydraulic motor 26 becomes a constant value a. Therefore, when the rotation speed N of the engine 2 becomes a rotation speed of b or more, the rotation of the hydraulic motor 26 becomes constant, so that the rotation of the alternator 1 also becomes constant.

Next, the operation of the voltage converter 20 will be described with reference to FIGS.

The voltage converter 20 comprises a first converter 17, a second converter 18 and relays 15 and 16. First
The converter 17 converts the voltage of 48V into the voltage of 12V, and the second
The converter 18 converts the voltage of 12V into the voltage of 48V. Further, the relays 15 and 16 are arranged so that their contacts are switched when the input / output switching signal 14 is input (in the drawing, ○ → ●). When ○ is in contact with relays 15 and 16, the first
Converter 17 is selected and the voltage of 48V from point A is the first
It is converted to 12V by the converter 17 and output to point B.
When relays 15 and 16 are in contact with ●, the second
The converter 18 is selected and the voltage of 12V from the point B is the second
It is converted to 48V by the converter 18 and output to the point A.
In this voltage converter 20, normally the first converter 17 is selected and the voltage of 48V at point A is converted to a voltage of 12V and output to point B. However, the abnormality detection device 13 outputs an input / output switching signal. 14
Only when is input, the contacts of relays 15 and 16 are switched, the second converter 18 is selected, and the 12V voltage at point B is set to 48V.
Converted to V voltage and output to point A.

FIG. 6 shows an example of a circuit diagram of the voltage converter 20.

The basic configuration of the first converter 17 and the second converter 18 is the same. The different parts are the winding numbers of the windings and the characteristics of the transistors.

Taking the first converter 17 as an example,
The DC voltage of 48V input from the point via relay 15 is
By the switching operation of the transistor, a square wave AC voltage is output to the secondary winding of the transformer. This AC voltage is rectified and smoothed by a diode to obtain a DC voltage of 12V, and this DC voltage is output to point B via the relay 16. Similarly, the second converter 18 also oscillates, transforms, rectifies, and smoothes the 12V voltage, converts it into a 48V voltage, and outputs the 48V voltage.

Next, the operation of this embodiment will be described.

First, the normal operation will be described.

The alternator 1 is generating electric power of 48V by the rotation of the engine 2 via the hydraulic device 10. The 48V electric power generated by the alternator 1 is supplied to the blower motor 3 via the switch 7, and the blower motor 3 operates by closing the switch 7 by the operation of the driver or a passenger. The 48V voltage generated by the alternator 1 is converted into a 12V voltage by the voltage converter 20 in which the first converter 17 is selected, and the 12V battery 5
And is supplied to the headlamp 6 via the switch 8.

Further, the abnormality detecting device 13 receives a discharge flow rate Q of the hydraulic device 10, more specifically, a discharge flow rate signal 11 indicating the flow rate of oil discharged from the hydraulic pump 25 to the hydraulic motor 26 and the engine speed N shown in FIG. The indicated engine speed signal 12 is input.

Now, when the relationship between the discharge flow rate signal 11 and the engine speed signal 12 in the abnormality detecting device 13 deviates from the characteristic shown in FIG. 4, that is, the engine speed N indicates a rotation of b or more. Nevertheless, when the discharge flow rate Q does not reach the set value a (less than a), it is determined that an abnormality has occurred in the power generation device 50, and it is determined that the power generation cannot be performed as set.

When the abnormality detection device 13 determines that an abnormality has occurred in the power generation device 50, the input / output switching signal 14 is output to the voltage converter 20 to switch the relays 15 and 16 (○ → ●) to output the first converter. The connection is switched from 17 to the second converter 18.
Therefore, the 12V battery 5 serves as a power supply source, and the 12V battery 5 transfers to the headlamp 6 and the voltage converter 20
The 12V voltage is converted to a 48V voltage to supply power to the blower motor 3. At the same time, the display signal 21 is output to the display device 21, and the travelable distance or travelable time in the future is calculated and displayed by the arithmetic unit 33 described later.

An example of the display device 21 is shown in FIG.

A voltage detector 34 is a 12V battery 5
The voltage value of is detected. Reference numeral 35 is a switch signal, which is output when the switch 7 connected to the blower motor 3 is closed. Further, the switch 8 connected to the headlamp 6 and the switch 31 connected to a number of other loads 32 similarly output the switch signal 35 when the switches 8 and 32 are closed.

The voltage value of the 12V battery 5 detected by the voltage detector 34 and the respective switch signals 35 are input to the arithmetic unit 33, and the arithmetic unit 33 uses these values to determine the possible traveling distance and traveling time in the future. To calculate.

When the abnormality detecting device 13 determines that the abnormality is present, the display signal 22 is input to the arithmetic device 33. When the display signal 21 is input, the LED 30 is turned on to indicate that the voltage converter 20 has switched from the first converter 17 to the second converter 18. Then, the travelable distance and the travelable time calculated by the computing device 33 are output to the display device 21 and displayed on the seven segment display body.

Next, the operation program of this embodiment will be described with reference to the flow chart shown in FIG.

First, at step 10, the rotation speed N of the engine 2 is detected by, for example, a crank angle sensor,
An engine speed signal 12 indicating the engine speed N is input to the abnormality detection device 13.

In step 20, it is judged whether the input engine speed N is the set value b or more. If it is the set value b or more, the process proceeds to step 30, and if it is less than the set value b, the process returns to step 10.

In step 30, the discharge flow rate signal 11 indicating the discharge flow rate Q discharged from the hydraulic pump 25 to the hydraulic motor 26 is input to the abnormality detecting device 13.

In step 40, the discharge flow rate Q is set to the set value a.
If it is less than the set value a, step
If it is equal to or greater than the set value a, the process returns to step 10.

At step 50, it is judged that an abnormality has occurred in the power generator 50. That is, when the discharge flow rate Q is less than a despite the engine speed N being the set value b or more,
It is determined that an abnormality has occurred in step S60 and the process proceeds to step S60.

In step 60, the abnormality detection device 13 outputs the input / output switching signal 14 to the voltage converter 20,
Relays 15 and 16 are switched by 70. By switching the relays 15 and 16, electric power is supplied from the 12V battery 5 to the blower motor 3.

Next, at step 80, the abnormality detection device 13 outputs the display signal 22 to the display device 21 to calculate and display the possible traveling distance and the possible traveling time thereafter, and the processing is terminated.

As described above, in this embodiment, the hydraulic device
The discharge flow rate Q of 10 and the engine speed N of the engine 2 are detected, and the abnormality of the power generation device 50 is determined from these, and when the power generation device 50 is determined to be abnormal, the input / output of the voltage converter 20 is changed. By switching and supplying power from the 12V battery 5 to the blower motor 3 and the headlamp 6, even when an abnormality occurs in the power generation device 50, the blower motor 3 is drastically changed.
Since the electric power is not stopped from being supplied to the loads such as the blower motor 3 and the like, there is no possibility that the load such as the blower motor 3 suddenly stops unlike the conventional case.
It does not impair the comfort of the vehicle.

Further, in this embodiment, the display device 21 is provided to display the travelable time or the travelable distance after the voltage converter 20 is switched. Therefore, the driver considers the displayed numerical value and travels. 12V to be able to do
This has the effect that some processing can be performed before the charge capacity of the battery 5 is exhausted.

Next, a second embodiment of the present invention will be described with reference to FIGS.

The configuration of the second embodiment will be described with reference to FIG. However, detailed description of the same components as those in the first embodiment will be omitted.

A three-phase AC signal (generator signal) 19 indicating the rotation speed of the alternator 1 and an engine rotation speed signal 12 indicating the rotation speed of the engine 2 are input to the abnormality detecting device 13. The input generator signal 19 is the abnormality detection device 13
Then, the period T of any one of the three-phase alternating currents of the alternator 1 is detected and compared with the set value. Here, as shown in FIG. 4, when the engine speed N of the engine 2 is equal to or greater than the set value b as described above, the discharge flow rate Q of the oil discharged from the hydraulic pump 25 to the hydraulic motor 26 becomes a constant value a. Therefore, the rotation speed of the generator 1 which is connected to the hydraulic motor 26 and rotates is constant. Therefore, as shown in FIG. 10, the cycle T of the three-phase alternating current indicating the rotation speed of the alternator 1 has a constant value, and this value is defined as the set value c.

Next, the operation of this embodiment will be described.

First, the normal operation is the same as that of the above-described first embodiment, so a detailed description will be omitted here.

Now, in the abnormality detecting device 13, when the engine speed N is equal to or higher than b shown in FIG. 4, and the cycle T of any one phase of the three-phase alternating current of the alternator 1 deviates from the set value c, that is, When T ≠ c, it is determined that an abnormality has occurred in the power generation device 50.

When the abnormality detection device 13 determines that an abnormality has occurred in the power generation device 50, the input / output switching signal 14 is output to the voltage converter 20 to switch the relays 15 and 16 (○ → ●) to output the first converter. The connection is switched from 17 to the second converter 18.
Therefore, the 12V battery 5 serves as a power supply source, and the 12V battery 5 is connected to the headlamp 6 and the voltage converter 20 is used.
The 12V voltage is converted to a 48V voltage to supply power to the blower motor 3. At the same time, the display signal 21 is output to the display device 21, and the arithmetic unit 33 calculates the possible traveling distance and the possible traveling time thereafter from the charging capacity of the 12V battery 5 and the usage status of the load, and displays the result. The illustration and description of the display device 21 are the same as those in the first embodiment, and are omitted here.

Next, the operation program of this embodiment will be described with reference to the flow chart shown in FIG.

First, at step 100, an engine speed signal 12 indicating the speed N of the engine 2 is input to the abnormality detecting device 13 by a crank angle sensor or the like.

In step 110, it is judged whether the input engine speed N is the set value b or more. If it is the set value b or more, the process proceeds to step 120, and if it is less than the set value b, the step 10 is executed.
Return to 0.

In step 120, a three-phase AC signal (generator signal) 19 indicating the rotation speed of the alternator 1 is input to the abnormality detecting device 13.

In step 130, the cycle T of any one of the three phase alternating currents of the alternator 1 is detected from the generator signal 19 and compared with a preset set value c. T ≠ c
If, then the process proceeds to step 140, and if T ≠ c, the process returns to step 100.

At step 140, it is judged that an abnormality has occurred in the power generator 50, and the routine proceeds to step 150.

In step 150, the abnormality detection device 13 outputs the input / output switching signal 14 to the voltage converter 20, and in step 160 the relays 15 and 16 are switched. This relay 15,
By switching 16 the electric power is supplied from the 12V battery 5 to the blower motor 3.

Next, in step 170, the display signal 22 is output from the abnormality detection device 13 to the display device 21, and the process is ended.

As described above, in the present embodiment, the engine speed N of the engine 2 and the cycle T of the three-phase AC of the alternator 1 are detected, and the abnormality of the power generator 50 is detected from these, and these are determined to be abnormal. When the judgment is made, the input / output of the voltage converter 20 is switched to supply the electric power from the 12V battery 5 to the blower motor 3 and the headlamp 6. Therefore, even when an abnormality occurs in these devices, the blower motor is suddenly changed. Since the power supply to the load such as 3 does not occur, the blower motor 3 is drastically changed as in the conventional case.
There is no possibility that the load of the vehicle will stop and the comfort of the vehicle will not be impaired.

[0074]

As described above, when the abnormality of the generator is detected and the voltage converter is configured to convert the low voltage to the high voltage when the abnormality occurs, the abnormality occurs in the generator. Also, in this case, the electric power is not suddenly stopped from being supplied to the load, so that the load is not suddenly stopped and the comfort of the vehicle is not deteriorated.

[Brief description of drawings]

FIG. 1 is a diagram for responding to a claim of the present invention.

FIG. 2 is a diagram showing a configuration of a first embodiment of the present invention.

FIG. 3 is a diagram showing a configuration of a hydraulic device.

FIG. 4 is an engine speed-discharge flow rate characteristic diagram

FIG. 5 is a diagram showing a configuration of a voltage converter.

FIG. 6 is a circuit diagram of a voltage converter

FIG. 7 is a diagram showing an example of a display device.

FIG. 8 is a flowchart of the first embodiment.

FIG. 9 is a diagram showing a configuration of a second embodiment.

FIG. 10 is a diagram showing a three-phase alternating current of an alternator.

FIG. 11 is a flowchart of the second embodiment.

FIG. 12 is a diagram showing a conventional vehicle power source.

[Explanation of symbols]

 1 ... Alternator 2 ... Engine 3 ... Blower motor 4, 20 ... Voltage converter 6 ... Headlamp 7, 8, 31 ... Switch 10 ... Hydraulic device 11 ... Discharge flow rate signal 12 ... Engine speed signal 13 ... Abnormality detection device 14 ... ON Output switching signals 15, 16 ... Relay 17 ... First converter 18 ... Second converter 21 ... Display device 22 ... Display signal 25 ... Hydraulic pump 26 ... Hydraulic motor 27 ... Oil pan 30 ... LED (light emitting diode) 32 ... Load 33 ... Arithmetic unit 34 ... Voltage detector 35 ... Switch signal 50 ... Generator

Claims (2)

[Claims] 1. An engine mounted on a vehicle, a generator for generating a high rated voltage using the engine as a drive source, a first load connected to an output terminal of the generator, and a low-voltage secondary battery. And a first terminal connected to the output terminal of the generator and a second terminal connected to the low-voltage secondary battery, and the voltage input to the first terminal is reduced to a low voltage. Convert,
A first voltage converting means for outputting to the second terminal, and a second voltage converting means for converting a voltage input to the second terminal into a high voltage and outputting the high voltage to the first terminal; A voltage converter that switches from the first voltage conversion means to the second voltage conversion means when the signal of is input, a second load connected to the second terminal of the voltage converter, and a generator of the generator. An abnormality detecting unit that detects an abnormality and outputs the first signal to the voltage converter when the abnormality is detected; and when the abnormality detecting unit detects an abnormality of the generator, A vehicle power supply device, characterized in that a signal is output to a voltage converter to switch from the first voltage converting means to the second voltage converting means. 2. The drive unit, wherein the generator is rotated by the engine as a drive source and outputs a constant rotation regardless of the rotation speed of the engine, and an output of the drive unit.
The vehicle power supply device according to claim 1, comprising an alternator that generates a high rated voltage at a constant rotation.