JP2533398Y2 - Self-excited single-phase alternator - Google Patents

Description

TECHNICAL FIELD The present invention relates to a self-excited single-phase alternator.

Conventional technology In general, a self-excited system is used in which an output winding on a stator core and an excitation winding for supplying an excitation current to a field winding on the rotor side are wound in a concentrated winding so that they are in the same phase. Single-phase AC generators have poor output voltage drooping characteristics with respect to load current, and especially when starting loads such as generators or lamps with a small starting resistance, where a large inrush current flows at startup, due to insufficient excitation current. It takes a long time to start, and the start fails.

Therefore, conventionally, as shown in FIG. 3, the output winding 5 on the stator core 4 and the exciting winding 6 for supplying the exciting current to the field winding 2 on the rotor 3 side have the same phase. In a self-excited generator wound in a concentrated winding, a second magnetic path is provided in parallel with and separate from the magnetic path L1 in which the output winding 5 and the exciting winding 6 are respectively wound. L2 is provided, and a second excitation winding 7 is wound around the stator core 4 in the second magnetic path L2, and the outputs of the excitation windings 6, 7 are fully output by full-wave rectifier circuits 8, 9, respectively. After wave rectification, the respective rectified outputs are superimposed and supplied to the field winding 2 on the rotor 3 side, thereby improving the drooping characteristics of the generator and reducing the starting resistance when starting a load with a small starting resistance. Also, a sufficient exciting current can be supplied to the field winding 2 to reliably start the field winding 2 (Japanese Patent Application Laid-Open No. 60-2199). No. 46).

The present invention relates to such a conventional self-excited single-phase alternator, in which the excitation circuit is simplified and the number of turns of the second excitation winding is reduced without sacrificing the drooping characteristics of the generator. It is intended to provide a self-excited single-phase alternating-current generator capable of reducing power consumption.

Configuration Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

In the self-excited single-phase alternator according to the present invention, the first
As shown in the figure, a rotor 3 in which a field winding 2 is wound around a rotor core 1 is disposed in the center, and concentrated winding is performed on an arm portion 41 of a stator core 4 disposed on one side thereof. The output winding 5 and the first excitation winding 6 are wound so as to be in phase with each other, and the stator core 4 disposed on the other side of the rotor 3.
The second excitation winding 7 is wound around the arm 42 at
The magnetic path L1 and the second magnetic path L2 are provided in parallel with each other.

Each output of the first exciting winding 6 and the second exciting winding 7 is half-wave rectified by diodes D1 and D2, respectively, and the respective half-wave rectified outputs are superimposed to form the field winding 2. It is supplied to.

In the figure, C is a smoothing capacitor. Terminal a is
For example, it is connected through a diode D3 for preventing backflow to a primary circuit in an ignition circuit of an engine of a transistor magneto type.

Thus, in the excitation circuit of the generator according to the present invention configured as described above, the output of each of the first and second excitation windings 6 and 7 is full-wave rectified as compared with the related art. Since the outputs of the first and second excitation windings 6 and 7 are half-wave rectified by the diodes D1 and D2, the energy of the excitation current supplied to the field winding 2 is reduced by half. This results in a decrease in the output voltage.

Therefore, in the present invention, in particular, by reducing the number of turns of the second excitation winding 7, the peak value of the current induced in the second excitation winding 7 is increased, and the field winding 2 is also subjected to half-wave rectification. The supplied exciting current is not reduced.

Here, as each winding specification, for example, a 1.3 × 2φ element wire is wound as the output winding 5 for 96 turns, and a 0.5 × 2φ element wire is wound as the field winding 2 for 1,100 turns. As the winding 6, a 0.7φ element wire is wound 13 turns, and as the second excitation winding 7, a 0.7φ element wire is wound 300 turns.

In the conventional generator, when the specifications of the output winding 5, the field winding 2 and the first excitation winding 6 are the same, a 0.7φ element wire is doubled as the second excitation winding 7. It is wound around 600 turns.

FIG. 2 shows that the rotation speed of the rotor 3 is 30
An example of the droop characteristic of the output voltage with respect to the load current when the present invention is applied when the load current rating is 17 A at 00 rpm is shown.

Further, in FIG. 2, the drooping characteristics of the conventional generator under the same conditions are shown by dotted lines.

According to the characteristics shown in FIG. 2, the short-circuit current is slightly reduced according to the present invention as compared with the conventional one, but the degree of the reduction is a matter of concern in actual use. This is outside the range where the starting characteristics of the electric motor and the like deteriorate, and there is no problem from the viewpoint of engine matching.

As described above, according to the present invention, the rectifying means in the excitation circuit can be simplified and the number of turns of the second excitation winding 7 can be greatly reduced while improving the drooping characteristics of the self-excited generator. Become like

Effect As described above, in the self-excited single-phase AC generator according to the present invention, the output winding and the first winding concentrated on the stator core side are concentrated.
A first magnetic path wound so as to be in phase with the first exciting path, and a second exciting winding wound around the stator core side are provided in parallel with the first exciting path. A circuit for half-wave rectifying the output of each of the first and second excitation windings with a diode, and superimposing the respective half-wave rectified outputs on the rotor side. The excitation circuit can be simplified while improving the droop characteristics of the generator, and the number of turns of the second excitation winding in the generator can be greatly increased. It has an excellent advantage that it can be reduced to contribute to the miniaturization and light weight of the generator.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of a self-excited single-phase AC generator according to the present invention, FIG. 2 is a diagram showing output voltage characteristics with respect to load current of the generator in the embodiment, and FIG. FIG. 3 is a circuit configuration diagram showing a conventional self-excited single-phase AC generator. 1 ... rotor core, 2 ... field winding, 3 ... rotor, 4
... stator core, 5 ... output winding, 6 ... first excitation winding, 7 ... second excitation winding

Claims (1)

(57) [Scope of request for utility model registration] An output winding and a first excitation winding which are concentratedly wound on a stator core side are wound so as to have the same phase.
And a second magnetic path provided in parallel with the first magnetic path and having a second excitation winding wound on the stator core side. A circuit for half-wave rectifying the output of each of the second excitation windings with a diode;
A self-excited single-phase alternator in which each half-wave rectified output is superimposed and supplied to the field winding on the rotor side.