JPH0496699A - Series/parallel switching alternator - Google Patents

Abstract

PURPOSE:To obtain a highly reliable and economic series/parallel switching alternator having simple constitution by a constitution wherein first and second three-phase full-wave rectifiers output three-phase full-wave rectified currents in parallel upon interruption of each unilateral switch to bring about parallel connection of both three-phase armature windings and the output current is doubled. CONSTITUTION:At first, rotational speed N is read out through a sensor for detecting the rotational speed of the rotary shaft of a generator and a judgment is made whether thus read out rotational speed N is within a range of 2000-3O00r.p.m. If it is not within the range, a gate trigger voltage VG is pulled to High level and silicon control rectifiers 5x, 5y, 5z are turned ON thus connecting first and second three-phase armature windings 1, 3 in series and outputting a doubled voltage to the outside. When the rotational speed of the generator is within that range, the gate trigger voltage VG is pulled to Low level and the silicon control rectifiers 5x, 5y, 5z are turned OFF thus connecting the first and second three-phase armature windings 1, 3 in parallel and outputting a doubled voltage to the outside.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a series-parallel switched alternating current generator. The present invention
Suitable for vehicle alternators.

[Prior art 1] In a vehicle alternator, if you try to increase the output at low speeds by increasing the number of turns in the armature winding, the output at high speeds will not increase; on the contrary, by reducing the number of turns in the armature winding, The fundamental problem is that if you try to improve the output in the low speed range, the output will be insufficient in the low speed range.

As a solution, Japanese Patent Application Laid-open No. 58-95999,
The three-phase armature windings are star-connected and the three-phase armature windings are independent of each other. Series-parallel switching connects these independent three-phase armature windings to the star-connected three-phase armature windings in series-parallel switching. An alternator having a switch group is disclosed.

In addition, Japanese Utility Model Application Publication No. 59-129400 discloses that auxiliary armature windings are connected in series to each phase of three-phase armature windings connected in a star shape, and the composite AC voltage is passed through a rectifier and a changeover switch to the field. Discloses feeding the coil. According to this configuration, a large voltage output from the auxiliary armature winding is applied to the field coil at low speeds to compensate for an abnormal drop in the generated voltage.

[Problems to be Solved by the Invention] However, such armature winding switching technology requires a total of six changeover switches, two for each phase, and has the disadvantage that the configuration of the changeover device is too complicated.

The present invention has been made in view of the above-mentioned problems, and an object to be solved is to provide a series-parallel switching type alternating current generator which has a simple device configuration and is excellent in reliability and cost efficiency.

"Means for Solving the Problems" The series-parallel switching alternator of the present invention has a first three-phase armature winding that outputs a three-phase AC voltage, and an input terminal or the first three-phase armature winding. a first three-phase full-wave rectifier connected to the first three-phase full-wave rectifier;
a second three-phase armature winding that outputs three-phase AC voltages having opposite phases and substantially equal magnitudes to the three-phase armature winding; and an input terminal connected to the second three-phase armature winding. , a second three-phase full-wave rectifier whose output end is connected in parallel to the output end of the first three-phase full-wave rectifier;
It is characterized by comprising a three-phase full-wave rectifier and a unidirectional switch that bridges phase output ends of the first and second three-phase armature windings that are in opposite phases to each other for each phase.

A unidirectional switch refers to a switch that conducts current in one direction when conducting, such as a silicon controlled rectifier or
It can be constructed by a series connection circuit of a diode and a normal two-terminal switch, relay, etc.

[Function] When each unidirectional switch is cut off, the first and second three-phase full-wave rectifiers respectively output three-phase full-wave rectified currents in parallel, and as a result, both three-phase armature windings are connected in parallel. , the output current is doubled.

When each unidirectional switch is bridged, the first and second three-phase armature windings are connected in series, resulting in twice the output three-phase full-wave rectified voltage, as will be explained in detail later. be done.

Embodiment] An embodiment of the series-parallel switching type alternating current generator of the present invention will be described with reference to FIG.

This series-parallel switching type alternator is a vehicle alternator, and is a field rotor (not shown) fixed to a generator rotating shaft (not shown) driven by a vehicle prime mover (not shown). It has a stator core (not shown) having three slots at equal pitches per electrical angle π (rad) around its outer periphery.

Phase windings X and X- are inserted into the Nth (N is an integer) slot of this stator core, phase windings y and y' are inserted into the N+1st slot, and phase windings are inserted into the N+2nd slot. winding 2,
2- is inserted. Each phase winding xSy, z, x=
y' and Z- each have the same number of turns.

The star-connected phase windings x, y, and z constitute a first three-phase armature winding 1, and each output end of these phase windings x, y, and z constitutes a first three-phase armature winding 1.
It is individually connected to each phase input terminal of the three-phase full-wave rectifier 2.

On the other hand, the phase windings X-1X- have opposite phases to each other, and the phase windings y
The phase windings x-1y' and Z- are connected in a star shape so that the phase windings 2-1Z- and 2-1Z- are in opposite phases to each other, and the phase windings x-1y' and Z- are connected in a star pattern to form the second three-phase armature winding. 3, and each output terminal of these phase windings X-y'7' is individually connected to each phase input terminal of the second three-phase full-wave rectifier 4.

The anode outputs E2a and 4a of the first three-phase full-wave rectifier 2 and the second three-phase full-wave rectifier 4 are grounded, and their respective cant output ends 2C14C are connected to the output end 9.

Furthermore, the output end of phase winding X is connected to the anode of silicon-controlled rectifier 5X, and the output end of phase winding X- is connected to the cathode of silicon-controlled rectifier 5X. Similarly, phase winding y
The output end of phase winding y- is connected to the anode of silicon-controlled rectifier 5y, and the output end of phase winding y- is connected to the cathode of silicon-controlled rectifier 5y. The output end of phase winding Z is connected to the anode of silicon-controlled rectifier 5Z, and the output end of phase winding 2' is connected to the cathode of silicon-controlled rectifier 57.

Next, the operation of the above device will be explained.

However, due to engine rotation, the first and second three-phase armature windings 1
．． 3 generates three-phase AC voltages having opposite phases to each other, and each three-phase AC voltage is subjected to three-phase full-wave rectification by first and second three-phase full-wave rectifiers 2.4.

(Parallel connection operation) In a state where the three silicon-controlled rectifier elements 5X, 5y, and 57 are cut off, the first and second three-phase armature windings 1.3 are in a parallel connection state. Therefore, the first and second three-phase full-wave rectifiers 2.4 output three-phase full-wave rectified currents in parallel to the output end 9, respectively.

(Series connection operation) When the three silicon-controlled rectifying elements 5X, 5y, and 5Z are bridged, the first and second three-phase armature windings 1.3 are connected in series.

For example, if we explain a period in which the phase difference voltage X-y (the phase difference voltage between the voltage of phase winding
-y, silicon controlled rectifier 5X, phase difference voltage = (x ”
-y-) -xy, a current flows in the order of the diode 42, and is output to the outside. Here, the front diodes of the first and second three-phase full-wave rectifiers 2.4 are reverse biased and cut off. Therefore, twice the phase difference voltage xy is output.

The same holds true for the period in which the phase difference voltage y-7 or Z-X is greater than other phase difference voltages, and in the end, the first and second three-phase armature windings 1.3 are connected in series.

Next, an example of a gate tripping circuit that controls the gates of the silicon-controlled rectifiers 5X, 5y, and 57 will be described.

This gate trigger circuit (not shown) is composed of a microcomputer, and its operation will be explained with reference to the flowchart in FIG. 2 and the rotation speed-voltage diagram in FIG. 3.

First, a rotation speed sensor that detects the rotation speed of the generator rotation shaft
(not shown) is read (SlO), and then it is checked whether the rotation speed N is in the range of 2000 to 3000 rpm (S12.514). If the rotation speed is N or 20
If it is outside the range of 00 to 3ooorpm, the good voltage VG is set to high level H, and the silicon controlled rectifier 5
Turn on X, 5y, and 5z, connect the first and second three-phase armature windings 1.3 in series, and output twice the voltage to the outside.

On the other hand, when the generator rotational speed is within the range of 2000 to 3000 rpm, the gut voltage VG is set to low level L, the silicon-controlled rectifiers 5X, 5y, and 5Z are turned off, and the first and second three-phase armature windings are turned off. Connect wires 1 and 3 in parallel to output twice the current to the outside.

As a result, the output (possible) current characteristics of the generator in this embodiment are as shown in Fig. 2.
A large output current is extracted in the rotation range of 000 to 300 rpm, and the output voltage is doubled when the generated voltage is low, 2000 rDm or less. In addition, Imax in Figure 2
is the maximum allowable current value for the power generation function.

In this embodiment, the three-phase armature winding 1.3 is Y-connected, but it may be △-connected or a combination of △-connected and Y-connected, and the number of turns of the armature winding of each phase may vary to some extent. I don't care if it happens.

(Second Embodiment) A second embodiment is shown in FIG. In order to facilitate understanding, components having the same functions as those of the first embodiment are given the same reference numerals.

In this embodiment, a circuit in which a diode D and a manual switch SW are connected in series is used as each unidirectional switch.

Further, in this embodiment, the neutral points NP and \P- of the first and second three-phase armature windings connected in a star shape are connected by a unidirectional switch consisting of the diode D and the manual switch SW. are doing.

The operation of this circuit device will be explained below. Note that the parallel operation that occurs when each manual switch SW is opened is the same as in the first embodiment, so a description thereof will be omitted.

To explain the case where each manual switch SW is closed and the output voltage of phase winding C
2. Current flows in the order of phase winding X-1NP-output terminal 9.

Here, the electromotive force of the phase winding X- is -X, and since the phase winding X is connected in the opposite direction to the above circuit, the total electromotive force becomes 2X after all.

In this embodiment, since the neutral point is connected, an output voltage of 2x can be obtained.

Using the generator of this embodiment, three types of output voltages (and their associated output currents) can be obtained.

For example, in the range of 1700 ppm or less and 3300 rpm or more, only the manual switch SW connecting the neutral points NP and \P- is cut off, and the remaining three manual switches SW are short-circuited. As a result, the output voltage becomes twice the phase difference voltage (for example, xy) as in the first embodiment.

1700rpm ~200Orpm, and 3000~3
In the range of 300 rpm, all manual switches SW including the manual switch SW connecting neutral points NP and NP' are short-circuited. As a result, the output voltage is 2 times the phase voltage (e.g.
Double. When outputting the above-mentioned phase difference voltage, a total of four phase windings are connected in series, and the internal voltage drop is large.In this case, a total of two phase windings are connected in series. Correspondingly, the C loss decreases and the output current increases.

When the generator rotation speed is within the range of 2000 to 3000 rpm, all manual switches SW are shut off. As a result, the output current doubles due to parallel operation.

In the above embodiment, the first and second three-phase armature windings may be inserted into the same slot or may be inserted into separate slots, and can be connected in series or parallel to two different three-phase alternating current generators. can also be applied.

[Effects of the Invention] As explained above, in the series-parallel switching AC generator of the present invention, the phase output ends of the first and second three-phase armature windings having opposite phases are bridged for each phase. Since it has a unidirectional switch, it is possible to provide a series-parallel switching alternator with an extremely simple device configuration and excellent reliability and economic efficiency.

[Brief explanation of the drawing]

Fig. 1 is an equivalent circuit diagram showing an embodiment of the series-parallel switching type alternating current generator of the present invention, and Fig. 2 is a silicon i! Flowcharts 1 to 3 showing the opening/closing control of the i-controlled rectifier, and Fig. 3 are diagrams showing the relationship between the generator rotation speed and the output current of this generator, and Fig. 4 shows the series-parallel switching type AC generator of the present invention. FIG. 3 is an equivalent circuit diagram showing another embodiment of the present invention. 1.3...Three-phase armature winding 2.4...Three-phase full wave rectifier 5X, 5y, 5z...Silicon controlled rectifier (unidirectional switch)

Claims (1)

[Claims] (1) a first three-phase armature winding that outputs a three-phase AC voltage; a first three-phase full-wave rectifier whose input end is connected to the first three-phase armature winding; and the first three-phase armature winding. a second three-phase armature winding that outputs three-phase AC voltages having opposite phases and substantially equal magnitudes to the armature winding; and an input end connected to the second three-phase armature winding, and an output a second three-phase full-wave rectifier whose ends are connected in parallel to the output end of the first three-phase full-wave rectifier; and mutually opposite phase output ends of the first and second three-phase armature windings, respectively. A series-parallel switching alternator comprising: a unidirectional switch that bridges each phase;