JPH11234992A - Power source equipment using magnet system ac generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To permit adjustment of a generator without special control, in a power source equipment supplying DC power to a load from a magnet generator through a rectifier circuit. SOLUTION: An exciting coil 5 for field adjustment which generates magnetic flux therefor is installed on the stator side of a magnet generator 1. The exciting coil 5 for field adjustment is inserted in the middle part of a path of a load current and excited by the load current. The winding direction of the coil 5 is so set that the magnet field of the rotor of the magnet generator is increased when the coil 5 is excited. By inserting the coil 5 in the path of the load and exciting the coil 5 with the load current itself, the magnet field is increased or decreased, so that the output of the magnet generator can be increased or decreased in accordance with increase or decrease of the load current.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply device for supplying DC power to a load at the output of a magnet type alternator.

[0002]

2. Description of the Related Art As a power supply device used for a vehicle driven by an internal combustion engine, a power supply device for converting the output of a magnet type AC generator driven by the internal combustion engine into a direct current through a rectifier circuit is often used. .

[0003] As is well known, a magnet-type alternator (hereinafter simply referred to as a magnet generator) is composed of a rotor having a magnet field and a stator having an armature coil. An AC voltage is induced in the armature coil by a change in magnetic flux that is attached to a prime mover such as an internal combustion engine and occurs with the rotation of the rotor.

Since the field of the magnet generator cannot be adjusted, it has been conventionally designed to drive the assumed maximum load. Therefore, in a power supply device that rectifies the output of the magnet generator and supplies power to the DC load, in order to prevent excessive power from being supplied to the load at light load, An output short-circuit switch for short-circuiting the output is provided, and when the terminal voltage of the load exceeds the set value or when the load current exceeds the set value, the output short-circuit switch is turned on to reduce the output of the magnet generator. The output was adjusted by short-circuiting.

However, if the output is adjusted by short-circuiting the output of the magnet generator, a large short-circuit current flows through the output short-circuiting switch at the time of output adjustment, so that the output short-circuiting switch has a large current capacity and is expensive. It is necessary to use a suitable material, which is not preferable.

Further, since a large short-circuit current flows through the output short-circuiting switch, a large loss occurs in the switch and heat is increased, and a large heat sink is required to cool the switch element, and the device becomes large. There was a problem of becoming.

Therefore, as shown in Japanese Patent Application Laid-Open No. 7-59319, a field-adjusting exciting coil for flowing a magnetic flux through a magnetic pole on the rotor side and a magnetic pole on the stator side of the magnet generator is provided on the stator side. And the configuration of the rotor magnet field,
The configuration is such that the magnetic field is increased when a magnetic flux is given from the field adjustment excitation coil, and the output of the magnet generator is increased by exciting the field adjustment excitation coil when driving a large load. Such a power supply has been proposed.

FIG. 12 shows the configuration of a conventional power supply device in which an excitation coil for field adjustment is provided on the stator side of a magnet generator to adjust the output. The rotor of the machine 1 has a rotor yoke formed in a cup shape, and is fixed to an inner circumference of a peripheral wall portion of the rotor yoke in a state of being arranged in a circumferential direction of the rotor yoke and has the same polarity in a radial direction. A plurality of arc-shaped permanent magnets magnetized in the above, and an arc-shaped ferromagnetic block disposed between the plurality of permanent magnets and fixed to the inner periphery of the peripheral wall of the rotor yoke. The inner peripheral surface of each permanent magnet and ferromagnetic block constitutes a rotor-side magnetic pole.

The stator of the magnet generator includes an armature core having a stator-side magnetic pole facing the rotor-side magnetic pole, and three-phase armature coils 1u to 1w wound around the armature core.
And a field-adjusting excitation coil 5 that, when excited, causes a field-adjusting magnetic flux to flow through the rotor-side magnetic poles and the stator-side magnetic poles.

The outputs of the armature coils 1u to 1w are bridged diodes Du to Dw and diodes Dx to Dx.
z is applied to the battery 3 through the diode bridge full-wave rectifier circuit 2, and the voltage across the battery 3 is applied to the field adjustment excitation coil 5 through the switch 6.

The field adjusting excitation coil 5 is wound so that when an exciting current is applied from the battery 3 through the switch 6, a magnetic flux flows through the ferromagnetic block to increase the magnet field of the rotor. The direction is set.

In the power supply device shown in FIG. 12, when the load connected to the battery 3 is light, the magnet field of the rotor is weakened by opening the switch 6 to de-energize the exciting coil 5 for field adjustment. To prevent the generator output from becoming excessive. Also, when the load connected to the battery 3 is heavy, such as at night when the headlamp is turned on, the switch 6 is closed to excite the field adjusting excitation coil 5, thereby increasing the magnet field to generate magnet power. Increase the power of the machine.

[0013]

In the power supply device shown in FIG. 12, the excitation current supplied to the field adjusting excitation coil 5 when the switch 6 is closed is determined by the terminal voltage of the battery 3, so that the load There has been a problem that the output of the magnet generator cannot be finely adjusted according to the various sizes.

In order to finely adjust the output of the magnet generator, a detection circuit for detecting a load current or a load voltage, and a magnitude of an excitation current flowing through a field adjustment excitation coil in accordance with a detection signal obtained from the detection circuit. It is conceivable to provide a control circuit having an excitation current adjustment circuit for adjusting the excitation current and to control the magnitude of the excitation current of the field adjustment excitation coil according to the state of the load. If a control circuit for controlling the control is provided, it is inevitable that the configuration of the device becomes complicated.

SUMMARY OF THE INVENTION An object of the present invention is to provide a power supply device using a magnet type alternator, in which the output of the magnet generator can be accurately controlled according to the load state without complicating the structure of the device. To be able to do it.

[0016]

SUMMARY OF THE INVENTION The present invention is applied to a power supply device for rectifying the output of a magnet type alternator and supplying direct current power to a load.

A power supply unit according to the present invention is a rotor yoke formed in a substantially cup-like shape having a peripheral wall portion and a bottom wall portion, and having a boss for attaching a rotating shaft provided at the center of the bottom wall portion. A plurality of arc-shaped permanent magnets fixed to the inner periphery of a peripheral wall of the rotor yoke and magnetized in the same direction in the radial direction while being arranged in the circumferential direction of the rotor yoke, and the plurality of permanent magnets An arc-shaped ferromagnetic block fixed to the inner periphery of the peripheral wall of the rotor yoke is provided between the permanent magnets and the inner peripheral surface of each of the permanent magnets and the ferromagnetic block constitutes a rotor-side magnetic pole. , A rotor armature having a stator-side magnetic pole opposed to the rotor-side magnetic pole, and an armature coil wound around the armature core, the rotor-side magnetic pole and the stator-side magnetic pole when excited. A stator having a field-adjusting excitation coil for flowing a field-adjusting magnetic flux through the A magneto AC generator with, and a rectifier circuit for supplying the output of the magnet type AC generator rectified by a load.

In the present invention, the exciting coil for field adjustment is inserted into the path of the DC load current flowing from the rectifier circuit through the load, and the exciting coil for field adjustment is excited by the DC load current. Also, the winding direction of the field adjustment excitation coil is set so that the magnetic flux flowing through the ferromagnetic block increases or decreases when the field adjustment excitation coil is excited to generate the field adjustment magnetic flux. deep.

As described above, the exciting coil for field adjustment is excited by the load current to increase or decrease the magnetic flux flowing through the ferromagnetic block provided on the rotor of the magnet generator according to the load current. Then, since the magnet field of the magnet generator can be increased or decreased according to the load current, the output of the magnet generator can be increased or decreased as the load current increases or decreases. Therefore, by appropriately setting the output of the magnet generator when the field adjustment excitation coil is in a non-excited state and the number of turns of the field adjustment excitation coil, the load can be reduced without providing a special control circuit. The output of the magnet generator can be increased or decreased according to the magnitude of the above, so that the output of the magnet generator can be adjusted to a magnitude suitable for the load.
Further, since it is not necessary to adjust the output by short-circuiting the magnet generator, it is possible to reduce the loss and increase the power generation efficiency.

Further, with the above configuration, the output of the magnet generator can be continuously changed according to the change of the load current. Therefore, the output of the generator can be finely adjusted according to the magnitude of the load. Can be.

In particular, if the magnet field is magnetized in accordance with the load current by exciting the field adjusting excitation coil with the load current, the DC motor may be driven as a load of the power supply unit, or may be rectified. When a load is connected between the DC output terminals of the circuit via an overcurrent protection device, the following advantages can be obtained.

That is, the rotation speed of the DC motor decreases as the load increases, but when the DC motor is driven by the power supply device, the armature current of the motor increases when the load of the motor increases. Accordingly, the exciting current of the exciting coil for field adjustment increases, so that the magnet field of the magnet generator is magnetized and the output of the generator increases. As a result, the electric power applied to the motor increases, so that the output torque of the motor increases, and a decrease in the rotation speed of the motor is suppressed.
Therefore, when the DC motor is driven by the power supply device, the motor can be driven at a substantially constant rotational speed regardless of the load on the motor.

When a load is connected between the DC output terminals of the rectifier circuit via an overcurrent protection device such as a fuse or a circuit breaker (breaker), as described above, the excitation coil for field adjustment is operated by the load current as described above. If the magnet field is energized and magnetized, the magnet field is weakened (no longer magnetized) when the load current becomes excessive and the overcurrent protection device shuts off. Since the output decreases, it is possible to prevent a high voltage from appearing between the DC output terminals of the rectifier circuit. Therefore, for example, when a device having high resistance such as a voltmeter is connected between the DC output terminals of the rectifier circuit,
The device can be prevented from being damaged by overvoltage.

As described above, when the field adjusting excitation coil is excited to increase the magnet field, the magnetic flux flowing through the ferromagnetic block does not increase infinitely.
Saturates at some point. Further, the output of the magnet generator is affected by the armature reaction and its increase is suppressed. Therefore,
As described above, even with the configuration in which the magnet field is increased according to the magnitude of the load current, the output of the magnet generator does not increase indefinitely, and the output of the generator increases to an appropriate level. Saturates.

In the present invention, if the magnet field is demagnetized in accordance with the load current by exciting the field adjusting excitation coil with the load current, the magnet field may be reduced when the load current increases. The demagnetization of the magnet generator increases, the output of the magnet generator is suppressed, and when the load current decreases, the demagnetization of the magnet field decreases (magnet field increases) and the output of the magnet generator Increases, the effect of keeping the load current constant against load fluctuations can be obtained.

For example, in a separately-excited DC generator, when the load current increases, the field current decreases due to an increase in the armature reaction. Conversely, when the load current decreases, the field current decreases due to a decrease in the armature reaction. Therefore, a control circuit for controlling the field current according to the load current is required to stably operate the generator while maintaining the field force constant regardless of the load current. If the current is supplied to the field coil using the power supply device according to the present invention, the field current can be kept constant without using a special control circuit.

Further, in the present invention, if a configuration is adopted in which the exciting coil for field adjustment is excited by the load current to demagnetize the magnet field in accordance with the load current, a resistance load (incandescent lamp, When an electric heater or the like is driven, a large inrush current can be prevented from flowing through a load having a low temperature and a low resistance value, so that the load can be prevented from being burnt due to the large inrush current.

As described above, when the field adjusting excitation coil is excited by the load current to demagnetize the magnet field, the magnet field is greatly demagnetized immediately when the magnet generator is started. However, since the demagnetization amount of the magnet field gradually increases at a constant rate with the increase of the load current, the magnet for exciting the field adjustment is excited by the load current as described above. Even when the field is demagnetized, the rise of the output of the magnet generator is not hindered, and the operation of the magnet generator is performed without any trouble.

According to the present invention, the direction of the load current flowing through the field adjusting excitation coil is switched in accordance with the state of the load, so that the magnet generator can be changed in accordance with the load current or the terminal voltage of the load. Can be optimally controlled.

In order to perform such control, for example, a connection is provided between a circuit for supplying a load current flowing from the rectifier circuit through the load and the exciting coil for field adjustment, so that the load current is A first state in which a load current energizing circuit and a field adjustment excitation coil are connected in series so as to flow from one end to the other end of the magnetic adjustment excitation coil; A controllable changeover switch circuit that switches to a second state in which the current-carrying circuit and the field-adjusting exciting coil are connected in series so that the current flows from the other end to one end; a load current flowing through the load or the load current; And a switch control circuit that switches the state of the changeover switch circuit in accordance with the terminal voltage of the switch.

In this case, the excitation coil for field adjustment generates a magnetic flux for field adjustment in a direction to increase the magnetic flux flowing through the ferromagnetic block when the changeover switch circuit is in the first state. Is set to generate a field adjusting magnetic flux in a direction to reduce the magnetic flux flowing through the ferromagnetic block in the second state. When the load current or the terminal voltage of the load is equal to or less than the set value, the switch control circuit switches the changeover switch circuit to the first
And the changeover switch circuit is controlled so that the changeover switch circuit is set to the second state when the load current or the terminal voltage of the load exceeds the set value.

When the changeover switch circuit and the switch control circuit are provided as described above, in a steady state, the magnet field is magnetized according to the increase of the load current to supply sufficient power to the load, and the load current becomes excessively large. The load can be protected by demagnetizing the magnet field and suppressing the output of the magnet generator when the load becomes too large or when the terminal voltage of the load becomes excessive. For example, taking the above configuration when driving a DC motor,
In the steady state, the changeover switch circuit is switched to the side that increases the magnet field by the load current so that it can cope with fluctuations in the output torque of the motor, and to prevent damage to the motor when excessive load torque is applied to the motor. The changeover switch circuit is switched to the side where the magnet field is demagnetized, so that the mechanical shock applied to the electric motor can be reduced.

[0033]

FIG. 1 shows an example of the configuration of a power supply device according to the present invention. In FIG. 1, reference numeral 1 denotes a magnet type AC generator, 2 denotes a rectifier circuit comprising a diode bridge full-wave rectifier circuit, Are batteries, which are configured similarly to the conventional power supply device shown in FIG. Although not shown, a load such as a lamp and an ignition device for an internal combustion engine is connected to the battery 3.

An excitation coil 5 for field adjustment is provided on the stator side of the magnet generator 1, and when the excitation coil 5 is excited, the field adjustment is performed through the magnetic pole on the rotor side and the magnetic pole on the stator side. The magnetic flux for use flows.

In the example shown in FIG. 1, one end and the other end of the field adjustment excitation coil 5 are connected to the negative terminal of the battery 3 and the negative output terminal of the rectifier circuit 2, respectively. 5 is inserted in the middle of the load current supply circuit so as to be excited by the load current itself.

In this example, when the field adjusting excitation coil 5 is excited by a load current, the magnetic field flowing through the rotor-side magnetic pole and the stator-side magnetic pole increases the magnet field of the rotor. Thus, the winding direction of the field adjusting excitation coil 5 is set.

The magnet generator used in the power supply device shown in FIG. 1 is configured as shown in FIGS. 2 and 3, for example. FIG.
And the magnet generator shown in FIG. 3 is configured such that the rotor side has 2n poles (n = 6 in the illustrated example) and the stator side has 3n poles, and the two rotor-side magnetic poles adjacent to each other have a circumferential direction. The three stator-side magnetic poles arranged in a row are opposed to each other to obtain a three-phase AC output. In FIGS.
Is a stator.

The rotor 10 has a peripheral wall portion 12a and a bottom wall portion 12a.
b and is formed in a substantially cup-like shape having a bottom wall 1
An iron rotor yoke 12 provided with a boss portion 12c1 for attaching a rotation shaft at the center of the rotor yoke 2b and a peripheral yoke portion of the rotor yoke 12 arranged in the circumferential direction of the rotor yoke 12 at equal angular intervals. N fixed to the circumference and magnetized with the same polarity in the radial direction
(N = 6 in the illustrated example) arc-shaped permanent magnets M1, M
, M6 and n arc-shaped ferromagnetic blocks m1, m2,..., M6 arranged between the plurality of permanent magnets and fixed to the inner periphery of the peripheral wall of the rotor yoke 12. Consists of In this rotor, the permanent magnets M1 to M6
And the ferromagnetic blocks m1 to m6 constitute a 12-pole magnet field, and the inner peripheral surfaces of the permanent magnets M1 to M6 and the inner peripheral surfaces of the ferromagnetic blocks m1 to m6 constitute rotor-side magnetic poles. doing.

The illustrated rotor yoke 12 has a peripheral wall 12a.
And a boss member 12c attached to the bottom wall of the yoke body. The yoke main body is formed by drawing an iron plate into a cup shape, and has a hole 12b1 formed in the center of the bottom wall 12b. The boss member 12c has a cylindrical boss portion 12c.
c1 and a flange portion 12c2 provided at one end of the boss portion in the axial direction. The boss portion 12c1 passes through a hole 12b1 provided at the center of the bottom wall portion 12b of the rotor yoke 12, and has a peripheral wall portion 12a. And a flange portion 12c2 is riveted to the bottom wall portion 12b of the rotor yoke. A tapered shaft fitting hole is formed inside the boss portion 12c1, and a taper portion provided at the tip of the rotating shaft of the internal combustion engine (not shown) is fitted into the shaft fitting hole to thereby form the rotor. The yoke 12 is attached to a rotating shaft of the engine. In the illustrated example, the direction of the taper of the shaft fitting hole inside the boss portion 12c1 is such that the rotor yoke 12 is attached to the rotation shaft of the engine with the opening thereof facing the opposite side to the case of the engine. Is set.

The permanent magnets M1 to M6 are formed in an arc shape, are arranged at equal angular intervals on the inner periphery of the peripheral wall 12a of the rotor yoke 12, and are fixed to the peripheral wall 12a by bonding. In the illustrated example, each permanent magnet is magnetized in the radial direction of the rotor yoke 12 with the same polarity so that the N pole and the S pole appear on the outer peripheral surface and the inner peripheral surface of each permanent magnet, respectively.

Each of the ferromagnetic blocks m1 to m6 is made of an iron piece formed in an arc shape, and like the permanent magnets M1 to M6, the peripheral wall 12a of the rotor yoke 12 is formed by bonding or the like.
, And a magnetic pole (N pole) having the opposite polarity to the inner magnetic pole (S pole in the illustrated example) of the adjacent permanent magnet appears on the inner circumferential surface of each ferromagnetic block.

The stator 11 includes an armature core 15, armature coils 1 u to 1 w wound around the armature core, and a field adjustment exciting coil 5 fixed to the armature core 15. Has become.

The armature core 15 has a structure in which 3n (18 in the illustrated example) tooth portions T1, T2,..., T18 radially protrude from the outer periphery of the annular yoke portion 15a. In this example, three consecutive teeth are arranged as one set of teeth, and a total of six sets of teeth (T1
T3), (T4 to T6),..., (T16 to T18), and U-phase to W-phase unit armature coils 1u 'to 1w' are respectively provided at three teeth constituting each tooth group. It is concentrated winding. Then, the unit armature coils of each phase are connected in series, parallel or series-parallel according to the purpose of use of the generator to form an armature coil of each phase, and the three-phase unit armature coils are connected in a star connection or The output terminals are derived from the three-phase armature coils by triangular connection (star connection in the illustrated example).

The illustrated stator 11 is attached to the inside of a cover (not shown) that covers the outlet of the rotating shaft of the engine.
A stator-side magnetic pole portion disposed concentrically with the rotor inside the rotor 10 and formed at the tip of each tooth portion of the armature core 15 faces a magnetic pole on the rotor 10 side via a predetermined gap. Let me do.

The field adjusting excitation coil 5 is wound around an annular bobbin 17 formed so as to surround the outer periphery of the boss 12c1 via a gap. The bobbin 17 around which the exciting coil 5 is wound is fixed to the armature core in a state where the bobbin 17 is fitted into an annular concave portion 15c formed at one axial end of the yoke portion 15a of the armature core 15. And the boss 12
It is arranged so as to concentrically surround the outer circumference of c1.

In the magnet generator shown in FIGS. 2 and 3, when the rotor 10 rotates, the magnetic flux linked to the unit armature coils constituting the armature coils 1u to 1w of the stator 11 alternates. Then, three-phase AC voltages are induced in the armature coils 1u to 1w.

The AC voltage induced in the armature coils 1 u to 1 w is rectified by the rectifier circuit 2 and supplied to the battery 3, which charges the battery 3. Since the field adjusting exciting coil 5 is excited by the charging current of the battery 3 to increase the magnet field of the rotor, when the charging current of the battery increases, the output of the magnet generator increases and the charging current increases. Decreases, the output of the magnet generator decreases.
When the charging of the battery is completed and the charging current becomes zero, the exciting coil for field adjustment becomes non-excited, so that the output of the magnet generator decreases to the minimum value at the rotation speed at that time.

In the magnet generator shown in FIGS. 2 and 3, the rotor side has 2n poles (n = 1, 2,...) And the stator side has 3n poles, and each salient pole on the stator side has Although the unit armature coil is concentratedly wound around the portion, the present invention is not necessarily limited to such a configuration.

FIGS. 4 and 5 show examples of the construction of another magnet generator which can be used in the present invention. In FIGS. 4 and 5, reference numeral 10 denotes a rotor, and reference numeral 11 denotes a stator. In this example, the rotor 10 has eight poles by four permanent magnets M1 to M4 and four ferromagnetic blocks m1 to m4. The armature iron core 15 has 24 teeth (stator-side magnetic poles) T1, T2,...
An annular core having 1, SL2,..., SL24 is used. The unit armature coils constituting the U-, V-, and W-phase armature coils are first unit coils 1u1 ', 1v1', and 1w1 'wound over three teeth, respectively. A second unit coil 1u2 'wound around three other teeth adjacent to the three teeth on which one unit coil straddles,
1v2 'and 1w2' are connected in series. Here, the first unit coil and the second unit coil are wound in different winding directions, and the unit armature coils in adjacent phases are also wound in different winding directions. .

The 24 dashed lines radially shown in FIG. 4 indicate the center positions of the teeth provided on the armature core 15, respectively. Eight dashed lines, each of which is displayed so as to protrude outward from the outer periphery, indicate the center of the magnetic pole of the rotor.

FIG. 6 shows the winding configuration of the magnet generator shown in FIGS. 4 and 5 taking the U-phase unit armature coil 1u 'as an example. In this example, three tooth portions T1 to T3 are provided. The first unit coil 1u1 'is wound through the slots SL1 and SL4 so as to straddle, and three teeth T4 adjacent to one of the three teeth T1 to T3 (delayed side in the rotation direction of the rotor). Through the slots SL4 and SL7, the second unit coil 1u2 'is wound so that its winding direction is different from that of the first unit coil 1u1' so as to straddle T6. The first unit coil 1u1 'and the second unit coil 1u2' are connected in series via a crossover, and the first and second unit coils 1u1 'and 1u2' are used to form a U-phase unit armature coil 1u.
'Is configured.

Although not shown in FIG. 6, the unit armature coil of the V phase has a slot SL extending over the teeth T2 to T4.
A first unit coil 1v1 'wound in the opposite direction to the U-phase first unit coil 1u1' through the second unit 2 and SL5;
The first unit coil 1v1 'and the second unit coil 1v2' wound in the opposite direction are connected in series through slots SL5 and SL8 so as to span from 5 to T7.

The W-phase unit armature coil has a tooth T3.
Through the slots SL3 and SL6 so as to cross the first unit coil 1v1 'of the V phase in the opposite direction to the first unit coil 1v1' and the slot SL6 so as to cross the teeth T6 to T8. And the first unit coil 1 through SL9
w1 'and a second unit coil 1w2' wound in the opposite direction are connected in series.

In the magnet generator shown in FIGS. 4 and 5, the field adjusting excitation coil 5 is wound around an annular bobbin 17 similarly to the magnet generator shown in FIGS. 2 and 3.
It is fitted and held in a recess 15 c provided in the armature core 15.

In the example shown in FIG. 1, the case where the charging current is supplied to the battery by using the battery 3 as a load is taken as an example. However, the present invention can also be applied to the case where power is supplied to a DC load other than the battery. Of course.

For example, as shown in FIG.
The present invention can be applied to the case where 0 is driven.
The rotation speed of the DC motor 20 decreases as the load increases, but when the motor is driven by the power supply device according to the present invention, the armature current of the motor 20 increases when the load of the motor 20 increases. As the exciting current of the field adjusting exciting coil 5 increases with the increase of the magnetic field, the magnet field of the magnet generator 1 is magnetized and the output of the generator increases.
As a result, the electric power applied to the electric motor increases, so that the output torque of the electric motor 20 increases, and the decrease in the rotation speed is suppressed. Therefore, the electric motor 20 can be operated at a substantially constant rotational speed regardless of the load.

Further, when a configuration is adopted in which the excitation coil for field adjustment is excited by the load current to increase the magnet field, as shown in FIG. When a load 22 is connected via an overcurrent protection means (a fuse in the illustrated example) 21 and a voltmeter 23 is connected between the DC output terminals of the rectifier circuit 2, the effect of protecting the voltmeter from overvoltage is obtained. Obtainable. That is, FIG.
When the load current becomes excessive and the overcurrent protection device 21 is cut off, the magnet field of the magnet generator 1 is weakened (no longer being magnetized), and the output of the magnet generator decreases. Therefore, it is possible to prevent a high voltage from appearing between the DC output terminals of the rectifier circuit 2. Therefore, the rectifier circuit 2
The voltmeter 23 connected between the DC output terminals can be prevented from being destroyed due to overvoltage. In FIG. 8, the same effect can be obtained when another device having a high resistance is connected instead of the voltmeter 23.

In the above example, when the field adjustment excitation coil 5 is excited by the load current to generate the field adjustment magnetic flux, the field adjustment excitation coil is increased so that the magnetic flux flowing through the ferromagnetic block increases. Although the winding direction of the coil is set, depending on the driving load, the magnetic flux flowing through the ferromagnetic block is reduced when the excitation coil for field adjustment is excited to generate the magnetic flux for field adjustment (the magnet field). The winding direction of the field adjusting excitation coil 5 may be set so as to demagnetize the magnetism.

FIGS. 9 and 10 show examples in which an advantageous effect can be obtained by setting the winding direction of the field adjusting excitation coil 5 so as to demagnetize the magnet field in accordance with the load current.

In the example shown in FIG. 9, the field coil 24a of the separately excited DC generator 24 is connected between the DC output terminals of the rectifier circuit 2. A load 25 is connected between output terminals of the armature 24b of the DC generator 24.

In the separately-excited DC generator 24, when the load increases and the load current increases, the field current flowing through the field coil 24a decreases due to the increase in the armature reaction, and the load current decreases. The field current increases due to the reduction of the child reaction. Therefore, in order to stably operate the generator while keeping the field force constant regardless of the load current, it is necessary to control the field current according to the load current. With the device, the field current can be kept almost constant without providing a special control circuit.

That is, by exciting the field adjusting exciting coil 5 with a load current, the magnet field is demagnetized in accordance with the load current. When the exciting current is supplied to the field coil 24a of the DC generator 24, when the armature reaction increases due to the increase of the armature current due to the increase of the load of the DC generator 24 and the field current decreases, the magnet generator Since the demagnetization amount of the magnet field 1 decreases and the output of the magnet generator increases, the exciting current of the separately excited DC generator increases. When the armature reaction decreases due to the decrease in the load of the DC generator 24 and the field current increases, the amount of demagnetization of the magnet field of the magnet generator 1 increases and the output of the magnet generator decreases. ,
The exciting current of the DC generator 24 decreases. In this way, the current flowing through the field coil is automatically kept constant with respect to the fluctuation of the output of the excitation type DC generator 24.
A stable operation can be performed by keeping the field force of the DC generator constant.

In the example shown in FIG. 10, an incandescent lamp 26 is connected between the DC output terminals of the rectifier circuit 2. When the incandescent lamp 26 is used as a load, a large inrush current flows immediately after lighting because the resistance value of the filament is low before lighting, and the load current decreases as the resistance value increases due to the temperature rise after lighting. Settles to a certain value. In order to prolong the life of the bulb, it is desirable to suppress an inrush current flowing immediately after lighting. When the electric bulb is turned on by the power supply device of the present invention having a configuration in which the excitation coil for field adjustment is excited by the load current to demagnetize the magnet field, a large inrush current may flow immediately after the lighting of the electric bulb. Then, since the magnet field is demagnetized and the output of the magnet generator is suppressed, it is possible to prevent a large inrush current from flowing. Also, if the current tends to decrease as the resistance value increases after the lamp 26 is turned on, the amount of demagnetization of the magnet field decreases and the output of the magnet generator 1 increases, so that the current flowing through the lamp decreases. Can be suppressed. Accordingly, the current flowing through the light bulb can be kept in a substantially constant range from immediately after the lighting of the light bulb 26 until the light reaches a steady state, and the life of the light bulb can be extended by preventing an excessive rush current from flowing. A similar effect can be obtained when driving a load that generates heat, such as an electric heater, in addition to the electric bulb. In the present invention, the excitation coil 5 flows through the field adjustment excitation coil 5 according to the state of the load. By employing a configuration in which the direction of the load current is switched, the output of the magnet generator can be optimally controlled according to the load current or the terminal voltage of the load. FIG.
Reference numeral 1 denotes a configuration example of a circuit used for performing such control. In FIG. 1, reference numeral 30 denotes a changeover switch circuit, and reference numeral 31 denotes a switch control circuit. The changeover switch circuit 30 is provided so as to connect between a circuit for supplying a load current flowing through the load from the rectifier circuit 2 and the excitation coil 5 for field adjustment, and converts the load current to the excitation coil 5 for field adjustment.
A first state in which the load current energizing circuit and the field adjustment exciting coil 5 are connected in series so that the load current flows from the one end 5a side to the other end 5b side, A switch circuit that switches to a second state in which the load current energizing circuit and the field adjustment exciting coil 5 are connected in series so as to flow from the end 5b side to the one end 5a side. First and second M whose sources are commonly connected
The drains of the OSFETs F1 and F2 are commonly connected, and the sources are the first and second MOSFETs F1 and F2.
And fourth MOS connected to the drain of F2 and F2
It comprises a MOSFET bridge circuit composed of FETs F3 and F4. In the illustrated example, the common connection point of the sources of the first and second MOSFETs F1 and F2 is connected to the DC output terminal on the negative side of the rectifier circuit 2. A DC motor 20 is connected to the DC output terminal on the positive side of the rectifier circuit 2.
And the other power supply terminal of the motor 20 is connected to the common connection point of the drains of the third and fourth MOSFETs F3 and F4 of the changeover switch circuit 30 via a small current detection resistor r1. Have been. In the illustrated example, the MOSFs on the opposite sides of the MOSFET bridge circuit
The state in which ET F1 and F4 are conducting is the first state, and the state in which the other diagonal MOSFETs F2 and F3 are conducting is the second state.

The switch control circuit 31 detects the load current from the voltage between both ends of the resistor r 1, and switches the changeover switch circuit 30 to the first state (FET) when the load current is equal to or less than the set value.
F1 and F4 are turned on and FETs F3 and F4 are turned off), and when the load current exceeds the set value, the changeover switch circuit 30 is switched to the second state (FETs F2 and F4).
3 is conducting and FETs F1 and F4 are off)
The changeover switch circuit 30 is controlled so that

As described above, when the changeover switch circuit 30 and the switch control circuit 31 are provided so as to switch the direction of the load current in accordance with the voltage or the load current at both ends of the load, the load current at the steady state is changed. Magnet field is increased according to the increase and sufficient power is supplied to the load, and when the load current becomes excessive or the terminal voltage of the load becomes excessive, the magnetic field is demagnetized and The load can be protected by suppressing the output of the magnet generator. When the DC motor 20 is driven as shown in FIG.
In order to cope with fluctuations in the output torque of the motor 20, and when the motor 20 is subjected to excessive load torque, switches the switch circuit 30 to the side that demagnetizes the magnet field in order to prevent damage to the motor. Thus, mechanical shock applied to the electric motor can be reduced.

[0066]

As described above, according to the present invention, the excitation coil for field adjustment is inserted into the path of the load current, and the excitation coil is excited by the load current itself to increase the magnet field. Alternatively, since the demagnetization is performed, the output of the magnet generator can be increased or decreased according to the increase or decrease of the load current. Therefore, by appropriately setting the output of the magnet generator when the field adjustment excitation coil is in a non-excited state and the number of turns of the field adjustment excitation coil, the load can be reduced without providing a special control circuit. The output of the magnet generator can be increased or decreased according to the magnitude of the above, so that the output of the magnet generator can be adjusted to a magnitude suitable for the load.

Further, according to the present invention, since it is not necessary to adjust the output by short-circuiting the magnet generator, it is possible to reduce the loss and increase the power generation efficiency.

Further, according to the present invention, since the output of the magnet generator can be continuously changed with the change of the load current, the output of the generator can be finely adjusted according to the magnitude of the load. it can.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration example of a power supply device according to the present invention together with its load.

FIG. 2 is a configuration diagram showing a preferred configuration example of a magnet generator used in the present invention.

FIG. 3 is a longitudinal sectional view of the magnet generator shown in FIG. 2;

FIG. 4 is a configuration diagram showing another preferred configuration example of the magnet generator used in the present invention.

5 is a longitudinal sectional view of the magnet generator shown in FIG.

FIG. 6 is an explanatory diagram for explaining a winding configuration of the magnet generator shown in FIGS. 4 and 5;

FIG. 7 is a circuit diagram showing a state where a load different from that of FIG. 1 is connected to the power supply device according to the present invention shown in FIG. 1;

8 is a circuit diagram showing a state in which still another load different from FIG. 1 is connected to the power supply device according to the present invention shown in FIG. 1;

FIG. 9 is a circuit diagram showing another configuration example of the power supply device according to the present invention together with its load.

10 is a circuit diagram showing a state in which another load is connected to the power supply device shown in FIG.

FIG. 11 is a circuit diagram showing another configuration example of the power supply device according to the present invention.

FIG. 12 is a circuit diagram showing a configuration example of a conventional power supply device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Magnet-type alternator 2 Rectifier circuit 3 Battery (load) 5 Excitation coil for field adjustment 20 DC motor (load) 21 Power fuse 22 Load 23 Voltmeter 24 Other excitation DC motor 25 Load

Claims (7)

[Claims] 1. A rotor yoke formed in a substantially cup-like shape having a peripheral wall portion and a bottom wall portion, and a boss portion for attaching a rotation shaft is provided at the center of the bottom wall portion, and a periphery of the rotor yoke. A plurality of arc-shaped permanent magnets fixed to the inner circumference of the peripheral wall of the rotor yoke in a state of being arranged in the same direction and magnetized with the same polarity in the radial direction, and arranged between the plurality of permanent magnets. A rotor having an arc-shaped ferromagnetic block fixed to the inner periphery of the peripheral wall of the rotor yoke, the inner peripheral surface of each permanent magnet and the ferromagnetic block constituting a rotor-side magnetic pole; An armature core having a stator-side magnetic pole opposed to the rotor-side magnetic pole, and an armature coil wound around the armature core, when excited, generate a field through the rotor-side magnetic pole and the stator-side magnetic pole. Magnet type having a stator having a field adjustment excitation coil for flowing an adjustment magnetic flux An AC generator; and a rectifier circuit for rectifying the output of the magnet type AC generator and supplying the rectified output to a load. The exciting coil for field adjustment is excited by a DC load current flowing through the load from the rectifier circuit. So that the magnetic flux flowing through the ferromagnetic block increases when the field adjusting excitation coil is excited to generate the field adjusting magnetic flux. A power supply device using a magnet type alternator, wherein a winding direction of a magnetizing excitation coil is set. 2. The load according to claim 1, wherein the load is a DC motor.
A power supply device using the magnet-type alternator according to item 1. 3. The power supply device according to claim 1, wherein the load is connected between a DC output terminal of the rectifier circuit and an overcurrent protection device including a fuse or a circuit breaker. . 4. A rotor yoke having a substantially cup-like shape having a peripheral wall portion and a bottom wall portion, and a boss portion for attaching a rotating shaft provided at a center of the bottom wall portion, and a periphery of the rotor yoke. A plurality of arc-shaped permanent magnets fixed to the inner circumference of the peripheral wall of the rotor yoke in a state of being arranged in the same direction and magnetized with the same polarity in the radial direction, and arranged between the plurality of permanent magnets. A rotor having an arc-shaped ferromagnetic block fixed to the inner periphery of the peripheral wall of the rotor yoke, the inner peripheral surface of each permanent magnet and the ferromagnetic block constituting a rotor-side magnetic pole; An armature core having a stator-side magnetic pole opposed to the rotor-side magnetic pole, and an armature coil wound around the armature core, when excited, generate a field through the rotor-side magnetic pole and the stator-side magnetic pole. Magnet type having a stator having a field adjustment excitation coil for flowing an adjustment magnetic flux An AC generator; and a rectifier circuit for rectifying the output of the magnet type AC generator and supplying the rectified output to a load. The exciting coil for field adjustment is excited by a DC load current flowing through the load from the rectifier circuit. So that the magnetic flux flowing through the ferromagnetic block decreases when the field adjusting excitation coil is excited to generate the field adjusting magnetic flux. A power supply device using a magnet type alternator, wherein a winding direction of a magnetizing excitation coil is set. 5. The power supply device according to claim 4, wherein the load is a field coil of a separately-excited DC generator. 6. The power supply device according to claim 4, wherein the load is a resistive load that generates heat when a load current flows. 7. A rotor yoke having a substantially cup-like shape having a peripheral wall portion and a bottom wall portion, and a boss portion for attaching a rotating shaft provided at the center of the bottom wall portion, and a periphery of the rotor yoke. A plurality of arc-shaped permanent magnets fixed to the inner circumference of the peripheral wall of the rotor yoke in a state of being arranged in the same direction and magnetized with the same polarity in the radial direction, and arranged between the plurality of permanent magnets. A rotor having an arc-shaped ferromagnetic block fixed to the inner periphery of the peripheral wall of the rotor yoke, the inner peripheral surface of each permanent magnet and the ferromagnetic block constituting a rotor-side magnetic pole; An armature core having a stator-side magnetic pole opposed to the rotor-side magnetic pole, and an armature coil wound around the armature core, when excited, generate a field through the rotor-side magnetic pole and the stator-side magnetic pole. Magnet type having a stator having a field adjustment excitation coil for flowing an adjustment magnetic flux An AC generator, a rectifier circuit for rectifying the output of the magnet type AC generator and supplying the rectified output to a load, and a circuit for supplying a load current flowing from the rectifier circuit through the load and the exciting coil for field adjustment. A first state in which the energizing circuit and the field adjustment excitation coil are connected in series so that the load current flows from one end to the other end of the field adjustment excitation coil. A controllable changeover switch that switches to a second state in which the energizing circuit and the field adjustment excitation coil are connected in series so that the load current flows from the other end to the one end of the field adjustment excitation coil. And a switch control circuit that switches a state of the changeover switch circuit in accordance with a load current flowing through the load or a terminal voltage of the load. Generating a field adjusting magnetic flux in a direction to increase a magnetic flux flowing through the ferromagnetic block when in the first state, and generating the field adjusting magnetic flux when the changeover switch circuit is in the second state; The winding direction is set so as to generate a field adjusting magnetic flux in a direction to reduce the magnetic flux flowing through the switch control circuit, and the switch control circuit is configured to switch the switch circuit when the load current or the terminal voltage of the load is equal to or less than a set value. A first state, and controlling the changeover switch circuit so that the changeover switch circuit is set to a second state when the load current or the terminal voltage of the load exceeds a set value. A power supply using an AC generator.