JP2001157496A - Vehicle mounted alternator and power supply circuit using it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize correct power supply to a plurality of types of vehicle mounted load of different working voltage efficiently through an inexpensive arrangement. SOLUTION: In order to output a plurality of types of voltage of different level from a single alternator 10 utilizing common engine power, a plurality of power generating sections are constituted by arranging a plurality of stator coils 26, 28 around a common field coil 24 and rectifying sections 31, 32 are provided on the output side of respective power generating sections. Each of rectifying sections 31, 32 is connected with a vehicle mounted load corresponding to the output voltage thereof thus constituting a power supply circuit for each load.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle-mounted alternator mounted on a vehicle such as an automobile as a power supply, and a power supply circuit using the same.

[0002]

2. Description of the Related Art FIG. 5 shows an example of a conventional general power supply circuit of a vehicle.

The alternator 10 shown includes an AC generator 11 that generates an AC voltage using engine power, and a rectifier circuit 12 that converts the AC voltage into a DC voltage. The DC power output from the rectifier circuit 12 is supplied as it is to a high-voltage DC load (generally a 12 V load), and excess power is stored in the vehicle battery 16. On the other hand, a low-voltage load whose operating voltage is lower than the output voltage of the rectifier circuit 12, such as a door ECU and an air conditioner E
A voltage converter (for example, a regulator or a small DC-DC converter) 18 is incorporated in ECUs such as a CU and an engine ECU, and the power output from the AC-DC converter 12 or the battery 16 is applied to each voltage converter 18.
After the pressure is reduced (for example, from 12 V to 5 V), it is supplied to the main body of each ECU.

FIG. 6 shows a specific configuration of the alternator 10.
Shown in The alternator 11 includes a field coil 13
And a stator coil 14. The field coil 13 is fixed around the rotating shaft 2 that rotates in conjunction with the engine. The stator coil 14 is arranged around the field coil 13,
An AC voltage is output to the rectifier 12 in accordance with the relative rotation with the rectifier 3.

[0005] The current value output from the rectifier 12 is detected using a sensor or the like, and is input to the field voltage control circuit 15. The field voltage control circuit 15 adjusts the voltage of the field coil 13 so that the output current of the rectifier 12 approaches a preset target value. By this field control, the output of the alternator 10 is stabilized.

[0006]

In recent years, electric components mounted on vehicles, that is, loads, are increasing and diversifying. For this reason, there is an increasing possibility that various types of electrical components having different operating voltages are mounted on the same vehicle.

For example, there has been an increasing movement to electrify on-vehicle actuators such as steering devices and brake devices. However, the operating voltage of these loads is considerably higher than the operating voltage (eg, 12 V) of conventional in-vehicle loads. It is an important issue to supply power appropriately to both such a high-voltage load and a conventional load.

As a means for solving such a problem, a DC-drop for voltage drop is provided downstream of an alternator for outputting a high voltage.
It is conceivable to provide a DC converter and supply power directly from the alternator to a high-voltage load, and to supply the power after lowering the output voltage of the alternator by the DC-DC converter to a low-voltage load. Can be
However, this DC-DC converter has a complicated configuration in which the DC voltage is once converted to an AC voltage by an inverter including a switching element, and the AC voltage is transformed by a transformer and then returned to a DC voltage by a rectifying unit. In addition, there is a disadvantage that the efficiency of the DC-DC converter is reduced because a considerable amount of power is consumed for driving the DC-DC converter.

In view of such circumstances, the present invention provides an in-vehicle alternator capable of efficiently supplying power to a plurality of types of in-vehicle loads having different operating voltages with an inexpensive configuration and a power supply circuit using the alternator. The purpose is to provide.

[0010]

As a means for solving the above-mentioned problems, the present invention comprises a plurality of power generating units for generating AC voltages having different levels by using a common engine power. Is provided with a rectifying unit that converts an AC voltage generated by the power generation unit into a DC voltage and outputs the DC voltage.

[0011] According to this configuration, each power generation unit generates AC voltages having different levels from each other by using the common engine power, and each AC voltage is converted into a DC voltage by each rectification unit and output. Therefore, by connecting the vehicle load corresponding to the output voltage to each rectification unit, appropriate power is supplied from a single alternator to various vehicle loads without using a DC-DC converter and suppressing its use. Power supply circuit can be configured.

As a specific configuration of the alternator, the alternator includes a field coil rotatably driven by engine power, and a plurality of stator coils disposed around the field coil. It is preferable that the stator coils are configured to output AC voltages having different levels from each other, and the rectifiers are provided on the output side of each stator coil. According to this configuration, a single field coil can be shared by each power generation unit, whereby the structure can be simplified and the current control of the field coil can be simplified.

In order to share the field coil as described above, for example, the plurality of stator coils may be arranged side by side in the rotation axis direction of the field coil.

In such a configuration in which the field coil is shared by the power generation units, in order to stabilize the output current or output voltage from each rectification unit, one of the rectification units must be connected to its output current or output voltage. It is effective to set the first rectifier to be controlled by the current control of the field coil, and to use the other rectifier as the second rectifier composed of a phase control type rectifier circuit. According to this configuration, the output of all the rectifiers can be stabilized by cooperatively performing the electric wire control of the field coil and the phase control of the second rectifier.

More specifically, detecting means for detecting a value corresponding to the current or voltage output from each of the rectifiers, and outputting the output value of the first rectifier detected by the detector as the output value And a field control means for controlling the current of the field coil so as to approach the target value set for the second rectifier. The output value of the second rectifier detected by the detection means is set to the target value set for this output value. By providing the phase control means for controlling the phase of the second rectifier so as to be close to each other, simultaneous execution of the current control of the field coil and the phase control of the second rectifier can be realized.

In this configuration, the first rectifier does not necessarily have to be a phase control type rectifier circuit, but may be, for example, a general diode rectifier circuit. A more excellent effect can be obtained by using a phase control type rectifier circuit in the same manner as the rectifier of No. 2.

That is, in this configuration, detecting means for detecting a value corresponding to the current or voltage output from each of the rectifiers, and the first detecting means for detecting a value corresponding to the current or the voltage output from the detecting means.
Field control means for adjusting the current of the field coil so that the output value of the rectifying unit approaches the target value set for the output value, and the output value of the first rectifying unit falls within a predetermined allowable range. First phase control means for controlling the phase of the first rectification unit so as to fall within the range, and an output value of the second rectification unit detected by the detection means to a target value set for this output value. Phase control means for controlling the phase of the second rectifier so as to approach the output, not only stabilizes the output of the first rectifier by current control of the field coil but also sharply increases the output. Even if there is a rise, this can be quickly suppressed by the phase control of the first rectifier, and as a result, more reliable circuit protection can be achieved.

Further, in the present invention, it is not always necessary to classify the plurality of rectifiers into the first rectifier and the second rectifier as described above. May be performed in cooperation with the phase control. That is, all the rectifiers are composed of a phase control type rectifier circuit, and a detecting means for detecting a value corresponding to a current or a voltage output from each rectifier, and an output value of each rectifier detected by the detector. And output control means for simultaneously performing the current control of the field coil and the phase control of each rectifier so that the output value approaches a target value set for the output value.

[0019]

FIG. 1 shows a preferred embodiment of the present invention.
This will be described with reference to FIG.

The alternator 10 according to this embodiment
As shown in FIG. 1, the AC power generator includes an AC power generator 20, a first rectifier 31, a second rectifier 32, an output voltage control circuit (output control means) 38, and current sensors 41 and 42.

As shown in FIG. 2, the AC power generator 20
A rotating shaft 22, a single field coil 24, and a plurality of (two high voltage and low voltage stator coils in the illustrated example) stator coils 26 and 28 are provided.

The rotating shaft 22 is connected to an output shaft of the engine via a drive transmission mechanism (not shown), and is driven to rotate by the power of the engine. A field coil 24 is fixed around an intermediate portion of the rotating shaft 22, so that the rotating shaft 22 and the field coil 24 rotate integrally.

The stator coil 26 is disposed around the field coil 24. The stator coil 26 has a U-phase, a V-phase, and a W-phase, and constitutes a three-phase AC generator (a power generation unit according to the present invention) that generates an AC voltage as the field coil 24 rotates. I have.

The stator coil 28 is also disposed around the field coil 24, and the stator coil 28 and the stator coil 26 are arranged in the axial direction of the rotating shaft 22. This stator coil 28 also
It has a U-phase, a V-phase, and a W-phase, and constitutes a three-phase AC generator (a power generation unit according to the present invention) that generates an AC voltage as the field coil 24 rotates.

That is, in the AC power generator 20, the field coil 24 is shared by two power generating units, and the stator coils 26 and 28 generate an AC voltage simultaneously and individually with the rotation thereof. Has become.

Further, in this AC power generator 20, both stator coils 26, so that the output voltage level of stator coil 26 during rotation of field coil 24 becomes higher than the output voltage level of stator coil 28.
28 are designed. Specifically, by making the number of turns of the two stator coils 26 and 28 and the cross-sectional areas of the coil wires different from each other, a difference is given to the output.

First rectifier 31 and second rectifier 32
Are provided on the output side of the stator coils 26 and 28, respectively, and convert an output voltage, that is, an AC voltage to a DC voltage. Then, the first rectifying unit 31
Is connected to an on-vehicle load corresponding to the output voltage, that is, a high-voltage load having a high working voltage.
In addition, a power supply circuit that supplies power from the single alternator 10 to both the high-voltage load and the low-voltage load is configured by connecting a vehicle-mounted load corresponding to the output voltage, that is, a low-voltage load with a low working voltage. It is supposed to be.

In the present invention, it goes without saying that an alternator and a battery may be used in combination as a vehicle-mounted power supply.

The alternator 10 according to this embodiment
As a feature of the invention, each of the rectifiers 31 and 32 is constituted by a phase control type rectifier circuit. In the example of FIG.
Reference numeral 2 denotes a three-phase full-wave rectifier circuit using six thyristors (rectifier elements capable of phase control) 30 as shown in FIG.
, V-phase, and W-phase are respectively connected to the bridge.
Therefore, the thyristors 30 constituting the rectifiers 31 and 32
Of the rectifiers 31 and 32 by changing the gate voltage of the rectifiers 31 (that is, changing the control angle of the thyristor 30).
32 output voltages can be adjusted.

On the output side of the first rectifier 31, a current sensor (detection means) 33 for detecting the output current I1 is provided. Similarly, on the output side of the second rectifier 32,
Current sensor (detection means) 3 for detecting the output current I2
4 are connected.

The output voltage control circuit 38 is electrically connected to the field coil 24 on the rotating shaft 22 via a brush 36 as shown in FIG. , 34 are also electrically connected. Based on detection signals (detection current values) of the current sensors 33 and 34, current control of the field coil 24 and phase control of the rectifiers 31 and 32 are simultaneously performed in parallel for the purpose of stabilizing the output current. It is configured as follows.

Specifically, the output voltage control circuit 38
It comprises a field control means 40, a first phase control means 41 and a second phase control means 42 as shown in FIG.

The field control means 40 performs field control for adjusting the current of the field coil 24 for the purpose of stabilizing the output voltage (high voltage) of the first rectifier 31. Comparison circuit 40a,
An arithmetic circuit 40b and a driver 40c are provided.
On the other hand, one end of the field coil 24
The other end is connected to the collector of a transistor (npn type in the illustrated example) 46, and the emitter of the transistor 46 is grounded. Therefore, this transistor 46
, The current flowing through the field coil 24 changes.

In the present invention, the field coil 2
The circuit for operating the current 4 is not limited to the one shown in the figure, and various other circuits such as other IC regulators can be applied.

The comparison circuit 40a includes the current sensor 3
3, the current value (output current value of the first rectifier 31) I1 is compared with a command current value (set target value) I1o input from the outside, and the current difference is calculated.
b. The arithmetic circuit 40b calculates a field control signal FS for bringing the input current difference close to 0,
The same signal FS is sent from the driver 40c to the transistor 4c.
6 is output to the base. With this configuration, field control (control of the current flowing through the field coil 24) for causing the detected current value I1 to approach the command current value I1o is executed.

The first phase control means 41 also performs control for the purpose of stabilizing the output voltage (high voltage) of the first rectifier 31, but the output control of the first rectifier 31 is basically performed. The first phase control means 41 performs auxiliary control, specifically, control for coping with a sudden current change due to an increase in load or the like.
As means for this, the first phase control means 41 includes a comparison circuit 41a, an arithmetic circuit 41b, and a driver 41c.
It has.

The comparison circuit 41a compares the current value I1 detected by the current sensor 33 with a preset allowable current value (a value that can surely prevent the circuit element from being damaged by overvoltage) I1c. Only when there is a large change in the output current value as the output current value exceeds (for example, when the load used suddenly increases), a comparison signal corresponding to the difference is output to the arithmetic circuit 41b.

When no comparison signal is input from the comparison circuit 41a (that is, when the detected current value I1 is steadily lower than the allowable current value I1c), the arithmetic circuit 41b outputs the first
The control angle of each thyristor 30 in the rectifying unit 31 of FIG.
(That is, perform phase control to maximize the output current) from the driver 41c to the gate of each thyristor 30 of the first rectifier 31.

On the other hand, when a comparison signal is input from the comparison circuit 41a (when the detected current value I1 fluctuates greatly and becomes temporarily higher than the allowable current value I1c).
, The driver 41c outputs the phase control signal G1 for increasing the control angle of each thyristor 30 in the first rectifier 31 to the gate of each thyristor 30 in the first rectifier 31. The output voltage of the first rectifier 31 is reduced by the increase in the control angle, and the circuit is protected from overvoltage. Moreover, the responsiveness of the output voltage in this phase control is several steps higher than the responsiveness of the output voltage in the field control, so that it is possible to quickly respond to a load change.

The second phase control means 42 controls the phase of the second rectifier 32 for the purpose of stabilizing the output voltage (low voltage) of the second rectifier 32. That is, since the output voltage of the second rectifier 32 changes due to the variation of the low-voltage load connected thereto and the current control of the field coil 24, the output voltage of the second rectifier 32 regardless of the change. The phase control is performed so as to stabilize the voltage. As a specific means for controlling the phase, the second phase control means 42 includes a comparison circuit 42a,
An arithmetic circuit 42b and a driver 42c are provided.

The comparison circuit 42a compares the current value I2 detected by the current sensor 34 with a command current value (set target value) I2o input from the outside, and outputs the current difference to the arithmetic circuit 42b. I do. The arithmetic circuit 42b has a phase control signal G2 for making the input current difference close to zero.
And the same signal G2 is output from the driver 42c to the gate of each thyristor 30 of the second rectifier 32. With this phase control, the output current of the second rectifier 32 is stabilized.

According to the above-described alternator 10, the high voltage current is output from the stator coil 26 and the first rectifier 31 in conjunction with the engine, and at the same time, the high voltage current is output from the stator coil 28 and the second rectifier 32. Since a low-voltage current is output, a high-voltage load and a low-voltage load of the vehicle are connected to the rectifiers 31 and 32, respectively, so that an appropriate DC-DC converter can be used without using an expensive DC-DC converter. A power supply circuit that efficiently supplies DC power can be configured.

However, the alternator according to the present invention has a D
This does not prevent the combined use with a voltage converter such as a C-DC converter, and the combination of the alternator and the voltage converter makes it possible to configure a wider variety of power supply circuits.

In addition, the present invention can adopt the following embodiments, for example.

In the present invention, three or more power generating units and rectifying units may be provided regardless of the specific numbers of the power generating units and the rectifying units. For example, in the structure shown in FIGS. 1 to 3, three or more stator coils may be provided around the field coil 24 in FIG. In this case, in order to stabilize the outputs of three or more rectification units provided corresponding to the respective power generation units, for example, one of the three or more rectification units is field-controlled in output current. What is necessary is just to make it the 1st rectification part, and let the other rectification parts be the 2nd rectification parts whose output currents are phase-controlled.

In the above embodiment, a plurality of stator coils 26 and 28 are provided around a common field coil 24 to share the field coil 24 with a plurality of power generation units. It is also possible to provide a field coil 24. However, by sharing the field coil 24 as described above, the number of components can be reduced and the structure can be simplified, the field control can be simplified, and the cost can be greatly reduced.

In the above embodiment, each of the rectifying sections 31 and 32
Although the output current is detected and the feedback control of the output current is performed, in the present invention, the output voltage of each rectifier may be detected and the feedback control may be performed.

The first rectifying unit 3 as in the above embodiment.
Output control of 1 is basically performed by field control,
When the output control of the second rectification unit 32 is performed by phase control, a simple diode rectification circuit can be used for the first rectification unit 31 instead of the phase control type rectification circuit. In this case, even if the current flowing through the field coil 24 decreases due to the field control, the second
Is designed so that the output current (or output voltage) of the rectifier 32 becomes larger than the target value, and the excess is reduced by increasing the control angle of the second rectifier 32. Good. This is basically the same in the embodiment shown in FIGS.

In the above embodiment, the rectifier on the high voltage side is the first rectifier 31 and the rectifier on the lower voltage side is the second rectifier 32. The first rectifier may be used, and the rectifier on the high voltage side may be used as the second rectifier.

· All the rectifiers 31, 3 as in the above embodiment.
2 is composed of a phase control type rectifier circuit, the output current (or output voltage) of each rectifier is roughly controlled by field control, and the output current (or output voltage) of each rectifier is precisely controlled by each field. You may make it perform by the phase control of a rectifier. That is, in the present invention, it is not always necessary to specify one rectifying unit whose output is adjusted by the field control. For example, the output of all the rectifying units may be stabilized in cooperation with the field control and the phase control. Good.

In the alternator 10, the AC power generator 20 and the rectifiers 31, 32 are integrated into a single housing, but they may be provided separately.

When a part of the vehicle-mounted load includes an AC load, the AC load may be directly connected to the AC generator without passing through the rectifier.

[0053]

As described above, the present invention provides a vehicle-mounted alternator including a plurality of power generation units that generate AC voltages having different levels from each other by using a common engine power. Since the power can be supplied to the on-vehicle load, the use of an expensive DC-DC converter is eliminated or minimized, and an inexpensive configuration is used for a plurality of types of on-vehicle loads that use different voltages. There is an effect that an appropriate power supply can be efficiently performed.

[Brief description of the drawings]

FIG. 1 is a circuit diagram of a vehicle-mounted alternator according to the present invention.

FIG. 2 is a schematic view showing a mechanical structure of the alternator.

FIG. 3 is a circuit diagram showing a connection state between each stator coil and a rectifying unit in the alternator.

FIG. 4 is a block diagram showing a configuration of an output voltage control circuit provided in the alternator.

FIG. 5 is a circuit diagram showing an example of a conventional vehicle power supply circuit.

FIG. 6 is a circuit diagram of a conventional vehicle-mounted alternator.

FIG. 7 is a schematic diagram showing a mechanical structure of the vehicle-mounted alternator of FIG. 6;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Alternator 20 Alternator generator 22 Rotating axis 24 Field coil 26, 28 Stator coil 30 Thyristor (rectifier capable of phase control) 31 First rectifier 32 Second rectifier 33, 34 Current sensor (detection means) 38 Output Voltage control circuit (output control means) 40 Field control means 41 First phase control means 42 Second phase control means

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Chen No. 1-7-10 Kikuzumi, Minami-ku, Nagoya-shi, Aichi F-term in Harness Research Institute, Inc. (Reference) 5H590 AA04 CA07 CC01 CC24 CD01 CE10 DD25 EB03 EB21 FA08 FB05 FC12 GA04 5H619 AA00 BB03 BB06 BB10 PP14 PP31

Claims (9)

[Claims] A plurality of power generating units that generate AC voltages having different levels using a common engine power;
An on-vehicle alternator, comprising: a rectifying unit that converts an AC voltage generated by the power generation unit into a DC voltage and outputs the DC voltage on the output side of each power generation unit. 2. The on-vehicle alternator according to claim 1, further comprising: a field coil rotatably driven by engine power; and a plurality of stator coils disposed around the field coil, wherein the field coil rotates. An alternator for a vehicle, wherein alternating current voltages having different levels are output from the respective stator coils, and the rectifiers are provided on the output side of the respective stator coils. 3. A vehicle alternator according to claim 2, wherein said plurality of stator coils are arranged side by side in a direction of a rotation axis of said field coil. 4. The alternator for a vehicle according to claim 2, wherein one of the rectifiers is a first rectifier whose output current or output voltage is controlled by current control of a field coil. An in-vehicle alternator, wherein the other rectifier is a second rectifier comprising a phase control rectifier circuit. 5. The alternator for a vehicle according to claim 4, wherein the first rectifier in addition to the second rectifier comprises a phase control rectifier circuit. 6. The on-vehicle alternator according to claim 4, wherein said detecting means detects a value corresponding to a current or a voltage output from each of said rectifiers, and said first detecting means detects said value. Field control means for controlling the current of the field coil so that the output value of the rectifying unit approaches a target value set for the output value,
Phase control means for controlling the phase of the second rectifier so that the output value of the second rectifier detected by the detector is closer to a target value set for the output value. A featured alternator for vehicles. 7. The on-vehicle alternator according to claim 5, wherein said detecting means detects a value corresponding to a current or a voltage output from each of said rectifying parts, and said first rectifying part detected by said detecting means. A field control means for adjusting the current of the field coil so that the output value of the first field coil approaches a target value set for the output value;
Phase control means for controlling the phase of the first rectification unit so that the output value of the rectification unit falls within a preset allowable range, and the second rectification unit detected by the detection means And a phase control means for controlling the phase of the second rectifier so that the output value of the second rectifier approaches the target value set for the output value. 8. The on-vehicle alternator according to claim 2, wherein all the rectifiers are constituted by a phase control type rectifier circuit, and a detecting means for detecting a value corresponding to a current or a voltage output from each rectifier. And output control means for simultaneously performing the current control of the field coil and the phase control of each rectification unit so that the output value of each rectification unit detected by the detection unit approaches a target value set for the output value. An alternator for a vehicle, comprising: 9. A power supply circuit for a vehicle, wherein each rectifier of the vehicle-mounted alternator according to claim 1 is electrically connected to a vehicle-mounted load corresponding to its output voltage.