JPH09135599A - Generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent the output voltage drop of a vehicle alternator by increasing an exciting current from a three-phase second stator coil, even when an output voltage generated by the three-phase second stator coil for self-exciting a rotor coil is low. SOLUTION: Positive and negative neutral diodes 35, 36 to be connected with the neutral point 13 of a Y-connected three-phase second stator coil 8 are added to a second three-phase full-wave rectification bridge circuit 10 in addition to a plurality of positive and negative neutral diodes 32, 33, so that an exciting current to be supplied to a rotor coil 6 can be acquired from the positive and negative neutral diodes 35, 36, too. This prevents the drop of a voltage generated by a vehicle alternator, because an AC voltage induced by a three-phase first stator coil 7 increases as the exciting current to be supplied to the rotor coil 6 increases, even when the output voltage of three-phase second stator coil 8 is low.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-exciting generator that self-excites a rotor coil with generated electric power. For example, an internal combustion engine is used only for electric power generation and the generated electric power is supplied to an external electric load. The present invention relates to a self-excitation type AC generator for a hybrid electric vehicle.

[0002]

2. Description of the Related Art Conventionally, for example, a field of an AC generator for a vehicle uses an electromagnet composed of a rotor coil (field coil) and a rotor core. Then, as a method of exciting the rotor coil, there are two methods, that is, a separately excited method in which the rotor coil is excited by an external DC power source, and a self-excited method using self-generated power.

Generally, in a self-excited AC generator, a method of separately exciting the rotor coil by an external DC power source before the rotor coil starts rotating is used for excitation by an exciting current supplied to the rotor coil. When power generation is started in the stator coil and the voltage generated in the exciting stator coil becomes higher than the power supply voltage of the external DC power supply, the AC voltage is rectified by the exciting rectifier circuit and the exciting current is supplied to the rotor coil. I started to encourage myself,
It is designed to shift from self-support to self-support.

In addition to the exciting stator coil, an AC voltage generated by a main stator coil wound around a stator core is rectified by a main rectifier circuit and converted into a DC output before being supplied to an external electric load. There is. Here, the main rectifier circuit is composed of a plurality of positive-side and negative-side diodes respectively connected to the ends opposite to the neutral point of the Y-connected three-phase stator coil. 5
2791 publication). The exciting rectifier circuit is composed of a plurality of positive side and negative side diodes connected to the ends opposite to the neutral point of the Y-connected three-phase stator coil in the same manner as the main rectifying circuit. Has been done.

[0005]

However, in a self-excitation type AC generator having a built-in exciting stator coil, the exciting voltage applied to the rotor coil is determined by the output voltage of the exciting stator coil. It has been difficult to increase the excitation power (magnetomotive force) of the rotor coil with respect to the output voltage of. That is, when the voltage generated by the exciting stator coil becomes low, the exciting voltage applied to the rotor coil also becomes low, so that the excitation cannot be sufficiently performed. As a result, the output power of the main stator coil is rapidly reduced, which causes a problem that the power generation performance of the self-excitation type AC generator is rapidly reduced.

[0006]

It is an object of the present invention to increase the electric power from the three-phase second stator coil even when the output voltage generated in the three-phase second stator coil for self-exciting the rotor coil is low. An object is to suppress a decrease in output power generated by a three-phase first stator coil that supplies power to an external electric load.

[0007]

According to the invention described in claim 1, when the prime mover rotates and an exciting current flows through the rotor coil, an AC output is generated in the three-phase first and second stator coils. . The AC output generated by the three-phase first stator coils is supplied to the external electric load after being rectified by the plurality of first rectifying elements and converted into the DC output. On the other hand, the AC output generated by the three-phase second stator coil is supplied to the rotor coil after being rectified by the plurality of second rectifying elements and the neutral point rectifying element and converted into the DC output.

Therefore, when the output voltage generated in the three-phase second stator coil decreases, the exciting voltage applied to the rotor coil from the plurality of second rectifying elements also decreases, and the exciting current supplied to the rotor coil also decreases. Less. However, since the exciting current is also supplied to the rotor coil from the neutral point rectifying element, the amount of decrease in the exciting current with respect to the decrease in the output voltage generated in the three-phase second stator coil is small. Accordingly, it is possible to obtain an effect that it is possible to suppress a decrease in output power that is generated in the three-phase first stator coil.

According to the second aspect of the invention, before the rotor is rotationally driven by the drive source, the initial exciting current is supplied from the external exciting means to the rotor coil. As a result, the rotor coil is excited to generate an AC voltage in the three-phase first and second stator coils. Then, when the excitation voltage of the rotor coil rises and the output voltage generated in the three-phase second stator coil becomes higher than the voltage of the external excitation means, the backflow prevention means moves from the self-excitation means side to the external excitation means side. The reverse flow of current is blocked. Therefore, it is possible to prevent the adverse effect of the external excitation means due to the overcurrent flowing through the external excitation means.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION

FIGS. 1 to 3 show a first embodiment of the present invention.
FIG. 1 is a diagram showing an electric circuit of a vehicle AC generator, and FIG. 2 is a diagram showing an electric circuit of a vehicle charging device.

The vehicle charging apparatus 1 uses, for example, an internal combustion engine (not shown) as a prime mover only for power generation, and uses the electric power generated by the vehicle AC generator 4 for charging the battery 2. It is installed in electric vehicles. As shown in FIGS. 1 and 2, the vehicle charging device 1 includes a battery 2, an external excitation power source 3, a vehicle AC generator 4 that charges the battery 2, and an output voltage of the vehicle AC generator 4. A regulator 5 for adjusting

The battery 2 is an external electric load of the present invention and supplies electric power to a vehicle traveling motor (not shown). In this example, a 300V battery is used. The external excitation power source 3 is an external excitation means of the present invention, and applies an initial excitation voltage to the vehicle AC generator 4 when the vehicle AC generator 4 is not rotating, thereby applying an initial excitation current to the vehicle. It is supplied to the AC generator 4, and a 12V battery is used in this example.

As shown in FIG. 1, the vehicular AC generator 4 generates AC voltage in the three-phase first and second stator coils 7 and 8 as the rotor coil 6 rotates. First three-phase full-wave rectification bridge circuit 9 for rectifying the AC output generated by the first-phase first stator coil 7 and second three-phase full-wave rectification for rectifying the AC output generated by the three-phase second stator coil 8. A bridge circuit 10 is provided.

The rotor coil 6 is an excitation winding, a field winding, a rotor winding, and a field coil that constitute a rotor together with a rotor core, slip ring, etc. (not shown), and is a shaft (not shown) driven to rotate by an internal combustion engine. ) Is wound around a central part of a Lundell-type rotor core that rotates integrally with a coil bobbin. When an exciting current flows through the rotor coil 6, one of the claw-shaped magnetic pole pieces of the rotor core becomes an N pole and the other of the claw-shaped magnetic pole pieces becomes an S pole.
The coil ends on both sides of the rotor coil 6 are connected to the second three-phase full-wave rectification bridge circuit 10 via slip ring terminals, slip rings, and brushes (not shown).

The three-phase first stator coil 7 is a three-phase second stator coil 8, a main armature winding, a main stator winding, and a main stator coil that form a stator together with a stator core (not shown). It is wound in a large number of slots (not shown) formed in the inner circumference of the stator core arranged so as to face the claw pole pieces. The three-phase first stator coil 7 is Y-connected (star-connected). That is, the coil ends on one side of the three-phase first stator coil 7 are connected at one place to form the neutral point 11, and the coil end 12 on the opposite side of the neutral point 11 is connected to the first three-phase full-wave rectification bridge. Circuit 9
Connected to

The three-phase second stator coil 8 is provided separately from the three-phase first stator coil 7, and the number of turns is 1 when the number of turns of the three-phase first stator coil 7 is 10. Thus, the excitation armature winding, the excitation stator winding, and the excitation stator coil have a smaller number of turns than the three-phase first stator coil 7. The three-phase second stator coil 8 is similar to the three-phase first stator coil 7 in that
It is wound in many slots.

The three-phase second stator coil 8 is Y-connected (star-connected) like the three-phase first stator coil 7. That is, the coil ends on one side of the three-phase second stator coil 8 are connected at one place to form the neutral point 13, and the neutral point 13 and the coil end 14 on the opposite side of the neutral point 13 are connected to the second side.
It is connected to the three-phase full-wave rectification bridge circuit 10.

The first three-phase full-wave rectification bridge circuit 9 is the DC output means of the present invention, and is a main winding side rectification circuit for rectifying the AC output input from the three-phase first stator coil 7. The first three-phase full-wave rectification bridge circuit 9 has three positive-side diodes 22 connected to the positive-side output ends of the three AC input terminals 21 and a negative-side output end of the three AC input terminals 21. It is composed of three connected diodes 23 on the negative side. The three AC input terminals 21 input the AC output from the three coil ends 12 of the three-phase first stator coil 7.

The positive and negative side diodes 22 and 23 are
The first rectifying element of the present invention is a semiconductor element that rectifies an AC voltage input from the three-phase first stator coil 7 and converts the AC voltage into a DC voltage. The positive side DC output terminals 24 are connected to the output sides of the three positive side diodes 22, and the negative side DC output terminals 25 are connected to the output sides of the three negative side diodes 23. Positive side, negative side DC output terminal 2
Reference numerals 4 and 25 are connected to the positive electrode (+ pole) and the negative electrode (− pole) of the battery 2 via DC input terminals 26 and 27, respectively.

The second three-phase full-wave rectifying bridge circuit 10 is the self-exciting means of the present invention, and is an exciting side rectifying circuit for rectifying the AC output input from the three-phase second stator coil 8. The second three-phase full-wave rectification bridge circuit 10 is connected to the positive electrode side output terminals of the three AC input terminals 31, the three positive electrode side diodes 32, and the negative electrode side output terminals of the three AC input terminals 31. Three negative side diodes 33, one positive side neutral point diode 35 connected to the positive side output end of one AC input terminal 34, and one negative side output end of the AC input terminal 34 It is composed of one negative electrode side neutral point diode 36 and the like connected to.

The three AC input terminals 31 input AC output from the three coil ends 14 of the three-phase second stator coil 8. The positive side and negative side diodes 32 and 33 are the second rectifying element of the present invention, and are semiconductor elements that rectify the AC voltage input from the three-phase second stator coil 8 and convert it into a DC voltage. One AC input terminal 34 inputs an AC output from the neutral point 13 of the three-phase second stator coil 8. The positive side and negative side neutral point diodes 35 and 36 are
The neutral point rectifying element of the present invention is a semiconductor element that rectifies an AC voltage input from the three-phase second stator coil 8 and converts the AC voltage into a DC voltage.

A positive side DC output terminal 37 is connected to the output side of the three positive side diodes 32 and one positive side neutral point diode 35, and three negative side diodes 33 and one negative side middle A negative side DC output terminal 38 is connected to the output side of the characteristic point diode 36. The positive electrode side DC output terminal 37 is connected to the positive electrode side power supply line 39 of the rotor coil 6, and the negative electrode side DC output terminal 38 is grounded.

Here, a flywheel diode 41 is connected in parallel with the rotor coil 6 between the positive power feeding line 39 and the negative power feeding line 40 of the rotor coil 6. The flywheel diode 41 has an anode side connected to the power supply line 40 and the external connection terminal 42, and a cathode side connected to the positive electrode side DC output terminal 37 and the power supply line 39.

A backflow prevention diode 43 is connected to the positive electrode side DC output terminal 37. The backflow prevention diode 43 is the backflow prevention means of the present invention, and the anode side is connected to the external connection terminal 44 and the cathode side is connected to the power supply line 39 via the positive side DC output terminal 37. The negative electrode side DC output terminal 38 is also connected to the external connection terminal 45.

The external connection terminal 44 is an input terminal for the initial excitation current, and is the external excitation power source 3 and the excitation current output terminal 5.
0. External connection terminals 42, 45
Is an exciting current control terminal for controlling the exciting current supplied to the rotor coil 6, and is connected to the regulator 5.

The regulator 5 controls the exciting current supplied to the rotor coil 6 to control the three-phase first stator coil 7
It is an output voltage adjusting means for adjusting the output voltage generated in. The regulator 5 includes a power transistor 51 as an exciting current control means, and the power transistor 51.
It has an integrated circuit 52 as a control means for turning on and off.

The power transistor 51 has a base connected to the integrated circuit 52 and a collector having an exciting current control terminal 53.
Is connected to the external connection terminal 42 via the, and the emitter is connected to the external connection terminal 45 via the excitation current control terminal 54. The integrated circuit 52 inputs, from the terminal 55, a command value for controlling the output voltage generated in the three-phase first stator coil 7 based on the battery voltage of the battery 2 or the power generation start signal of the upper controller.

[Operation of First Embodiment] Next, the operation of the vehicle charging device 1 of this embodiment will be briefly described with reference to FIGS. 1 and 2.

At the time of power generation, the AC voltage induced in the three-phase first stator coil 7 is generated by the rotation of the rotor that has become an electromagnet due to the flow of exciting current. Side, negative side diodes 22, 23 are rectified and converted into DC output, and positive side and negative side DC output terminals 2
It outputs to the battery 2 via 4, 25.

At this time, the output voltage (the output of the first stator coil 7 in this example) proportional to the winding ratio (turn number ratio) with the three-phase first stator coil 7 is applied to the three-phase second stator coil 8. A voltage value of 1/10 of the voltage) is induced. This output voltage is applied to the second three-phase full-wave rectification bridge circuit 10
The positive and negative side diodes 32 and 33 and the positive and negative side neutral point diodes 35 and 36 are rectified and converted into a DC output, which is used as an internal excitation power supply for the rotor coil 6.

However, the exciting voltage from the second three-phase full-wave rectifying bridge circuit 10 does not exist before the rotor of the vehicle alternator 4 starts rotating or when the rotating speed is low. Alternatively, the excitation voltage that is sufficient to excite the rotor coil 6 has not been reached. At this time, since the power transistor 51 is turned on by the energization signal of the integrated circuit 52,
It is connected to the excitation current output terminal 50 of the external excitation power source 3 via the external connection terminal 44. As a result, the initial excitation voltage (for example, 12 V) is applied from the external excitation power source 3, so that the excitation current is supplied to the rotor coil 6.

At this time, the exciting current from the external exciting power supply 3 is the exciting current output terminal 50 → external connection terminal 44 → feed line 39 → rotor coil 6 → feed line 40 → external connection terminal 4
2 → Excitation current control terminal 53 → Power transistor 51 →
It flows through the electric circuit of the vehicle charging device 1 like the external excitation power source 3.

Then, the excitation current supplied from the external excitation power source 3 to the rotor coil 6 causes the three-phase first and second stator coils 7 and 8 to start power generation, and the first and second three-phase full-wave rectification. The output voltage from each of the bridge circuits 9 and 10 increases. Then, the second three-phase full-wave rectification bridge circuit 10
When the excitation voltage of 1 exceeds the initial excitation voltage of the external excitation power source 3 (for example, 12 V), the backflow prevention diode 43 enters the reverse bias state, and the excitation current from the external excitation power source 3 does not flow into the rotor coil 6.

Therefore, it is possible to prevent adverse effects of the external excitation power source 3 such as solution leakage due to overcurrent flowing through the external excitation power source 3. After that, the external excitation in which the rotor coil 6 is excited by the power supply voltage of the external excitation power source 3 shifts to the self-excitation in which the rotor coil 6 is excited by the output voltage of the three-phase second stator coil 8.

At this time, the exciting current generated in the three-phase second stator coil 8 includes three positive-side diodes 32 and one positive-side neutral point diode 35 → positive-side DC output terminal 37 → feed line 39. → rotor coil 6 → power supply line 40 →
External connection terminal 42 → excitation current control terminal 53 → power transistor 51 → excitation current control terminal 54 → external connection terminal 4
5 → negative side DC output terminal 38 → flows through the electric circuit of the vehicle charging device 1 like three negative side diodes 33 and one negative side neutral point diode 36.

[Effects of the First Embodiment] As described above, in the case of the vehicle AC generator 4 capable of self-exciting the rotor coil 6, the output voltage (rotor coil) induced in the three-phase second stator coil 8 is generated. 6 is an output voltage induced in the three-phase first stator coil 7 (generated voltage of the vehicle alternator 4), that is, between the positive electrode side and the negative electrode side DC output terminals 24, 25. It is almost proportional to the voltage value.

Therefore, as the output voltage induced in the three-phase second stator coil 8 becomes smaller, the exciting voltage that can be applied to the rotor coil 6 also becomes smaller, and as shown by the straight line A in the graph of FIG. The exciting current supplied to 6 also decreases. As a result, the curve B shown in the graph of FIG.
As described above, the output power of the vehicle AC generator 4 (three-phase first stator coil 7) decreases.

However, in this embodiment, in addition to the positive and negative side diodes 32 and 33, the direct current is output from the positive and negative side neutral point diodes 35 and 36. As indicated by the straight line C shown in the graph of No. 3, the decrease amount of the exciting current supplied to the rotor coil 6 becomes small. As a result, the curve D shown in the graph of FIG.
As described above, since the output power of the vehicle AC generator 4 (three-phase first stator coil 7) increases with respect to the curve B, it is possible to suppress a decrease in the output power of the vehicle AC generator 4.

Further, if a neutral point diode is inserted in the first three-phase full-wave rectification bridge circuit 9, an increase in generated power (output power) can be expected, but in this case, noise such as ripples increases in the DC output. Problem arises. On the other hand, in this embodiment, basically, the exciting power of the rotor coil 6 is increased to increase the output power of the vehicle alternator 4, so that the increase of noise due to the addition of the neutral point diode is small. You can also get the effect.

Further, the first three-phase full-wave rectification bridge circuit 9
A large capacity diode corresponding to the output voltage is required to insert the neutral point diode into the neutral point diode. In this embodiment, the positive side and the negative side neutral point diodes 35 and 36 are connected to the first three-phase full wave. Since it is placed in the second three-phase full-wave rectifying bridge circuit 10 that generates an output voltage that is 1/10 of that of the rectifying bridge circuit 9, there is an advantage that a small capacity diode is sufficient.

[Second Embodiment] FIG. 4 shows a second embodiment of the present invention and is a view showing an electric circuit of an automotive alternator.

In this embodiment, the second three-phase full-wave rectification bridge circuit 10 is provided with only the positive-side neutral point diode 35 as a neutral point diode so that the number of parts is reduced and the vehicle AC generator 4 is reduced. We are trying to reduce the price of. Even with such a configuration, the effect of increasing the output power of the vehicle AC generator 4 (three-phase first stator coil 7) by increasing the exciting current applied to the rotor coil 6 can be obtained.
However, the effect of improving the output power of the vehicle alternator 4 is
It goes without saying that the embodiment is superior.

[Third Embodiment] FIG. 5 shows a third embodiment of the present invention, and is a view showing an electric circuit of a vehicle AC generator.

In this embodiment, only the negative side neutral point diode 36 is inserted as the neutral point diode in the second three-phase full-wave rectification bridge circuit 10 to reduce the number of parts and to provide the vehicle alternator 4 We are trying to reduce the price of. Even with such a configuration, the effect of increasing the output power of the vehicle AC generator 4 (three-phase first stator coil 7) by increasing the exciting current applied to the rotor coil 6 can be obtained.
However, the effect of improving the output power of the vehicle alternator 4 is
It goes without saying that the embodiment is superior.

[Modification] In this embodiment, the present invention is applied to a vehicle AC generator 4 as a generator that is rotationally driven by a series-type engine mounted on a hybrid electric vehicle. Parallel electric hybrid vehicle internal combustion engine used not only for driving but also for direct driving of wheels, internal combustion engine for other vehicles, fixed-field internal combustion engine, or other power generation driven by a prime mover such as an electric motor It may be applied to the machine.

In this embodiment, the diode is used as the first and second rectifying elements or the neutral point rectifying element.
Si-MOS as the second rectifying element or the neutral point rectifying element
You may use semiconductor switching elements, such as FET, SiC-MOSFET, and a bipolar transistor. Also,
You may use these in combination.

In this embodiment, only the rotor coil 6 is wound around the rotor core. However, in order to increase the excitation power of the rotor coil 6, one rotor coil 6 and one rotor coil 6 are provided between the rotor core 6 and adjacent claw pole pieces. The above permanent magnets may be arranged. In this embodiment, the battery 2 is used as the external electric load, but an electric device such as a lighting device, an engine starting device, or an electric actuator mounted on a vehicle may be used as the external electric load. In this embodiment, the external excitation power source 3 is used as the external excitation means, but other generators other than the vehicle AC generator 4 may be used as the external excitation means.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an electric circuit of a vehicle AC generator (first embodiment).

FIG. 2 is a circuit diagram showing an electric circuit of a vehicle charging device (first embodiment).

FIG. 3 is a graph showing the relationship between output power / excitation current and output voltage (first embodiment).

FIG. 4 is a circuit diagram showing an electric circuit of a vehicle AC generator (second embodiment).

FIG. 5 is a circuit diagram showing an electric circuit of a vehicle AC generator (third embodiment).

[Explanation of symbols]

 1 Vehicle Charging Device 2 Battery (External Electric Load) 3 External Excitation Power Supply (External Excitation Means) 4 Vehicle AC Generator 6 Rotor Coil 7 First Stator Coil 8 Second Stator Coil 9 1st Three-Phase Full-Wave Rectifier Bridge Circuit (DC output means) 10 Second three-phase full-wave rectification bridge circuit (self-exciting means) 11 Neutral point 12 Coil end 13 Neutral point 14 Coil end (reverse side end) 22 Positive side diode (first rectifying element) 23 Negative Side Diode (First Rectifying Element) 32 Positive Side Diode (Second Rectifying Element) 33 Negative Side Diode (Second Rectifying Element) 35 Neutral Point Diode (Neutral Point Rectifying Element) 36 Neutral Point Diode (Neutral Point rectifier) 43 Backflow prevention diode (backflow prevention means)

Claims (3)

[Claims] 1. A rotor coil wound around a rotor that is rotatably driven by a prime mover; (b) Wound around a stator that rotates relative to the rotor;
A three-phase first stator coil that generates an AC output in accordance with the rotation of the rotor coil, and (c) a plurality of first rectifying elements that are respectively connected to these first stator coils, DC output means for supplying a DC output rectified by one rectifying element to an external electric load, and (d) the three-phase first stator coil is wound around the stator in parallel with the rotation of the rotor coil. A three-phase second stator coil that generates an AC output and has a neutral point by connecting one end of each with a Y connection, and (e) an end opposite to the neutral point of the second stator coil. A plurality of second rectifying elements connected to each other, and a neutral point rectifying element connected to a neutral point of the three-phase second stator coil. DC output rectified by the rectifying element Generator with a self-exciting means for supplying the serial rotor coil. 2. The generator according to claim 1, wherein an external excitation means for supplying an initial excitation current to the rotor coil is connected to the self-excitation means, and the self-excitation means and the external excitation means are connected to each other. A generator, characterized in that a backflow preventing means for preventing a backflow from the self-exciting means to the external exciting means is connected in between. 3. The generator according to claim 1, wherein the generator is a variable that changes an exciting current supplied to the rotor coil to change an output voltage output from the DC output means. A generator characterized by being an output voltage type generator.