JP2613888B2 - Power generator that can supply power individually - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a power generator capable of individually supplying power, in particular, for example, a power generator having a plurality of main power generation windings for a welding power source.
Individual load-side voltage controlled by thyristor control when a load is supplied from the main power generation winding to a load without changing the no-load voltage of at least one main power generation winding, so that power supply control can be performed independently of each other. The present invention relates to a power generator capable of supplying power.

[Conventional technology]

The applicant of the present application has previously filed Japanese Utility Model Application No. 60-183549,
A generator using a rotor core as shown in FIG. 4 is proposed,
As shown in FIG. 5, it has been proposed to perform welding using the output from the main power generation winding and to supply power to a general AC load using the indicated AC output.

In FIG. 4, 1 indicates a rotor core, and 2 indicates a rotor shaft hole. In Fig. 5, 3 is a generator, 4 is the main generator winding, and 5 is
AC output winding, 6 is an excitation winding for supplying a field current, 7 is a field winding wound on the rotor core, 8 is a rectifier circuit, 9 Is a field rectifier, and 10 is a volume.

As disclosed in Japanese Utility Model Application No. 60-183549, etc., the rotor core is formed as shown in FIG. And power supply to the AC load can be performed in parallel.

In the case of the form shown in FIG. 5, the current of the welding output is controlled by controlling the volume 10 to control the field current. At this time, the AC output voltage is also controlled. fluctuate. In particular, when the resistance value of the volume 10 becomes large, the AC output voltage is greatly reduced, and it becomes difficult to obtain a desired AC output. 5 is improved, and a plurality of main power generation windings 4 shown in FIG.
It is also desirable that a plurality of persons can perform welding independently of each other as described above. However, since the volume 10 is controlled, no load is applied to all of the plurality of main power generation windings 4-1 and 4-2. The induced voltage itself fluctuates together and cannot control the welding current independently.

In order to solve this point, after providing a plurality of main generator windings, the output of at least one of the main generator windings (of course,
It has been considered that it is possible to control the load terminal voltage at the time of load for supplying power to the load by thyristor control, and to be able to perform power supply control independently.

[Problems to be solved by the invention]

By controlling the output voltage, it is possible to independently control power supply to a plurality of loads. However, this in the case of employing the the scheme, the primary generating the no-load induced voltage induced in the winding is not changed Ya the output voltage (i.e. load terminal voltage) of the predetermined level for example V ₁ level
From becoming the control is performed so that V ₂ level and V ₃ levels, load terminal voltage at no load becomes the V ₁ level and V ₂ level and V ₃ levels, FIG. 6 (A) It has voltage-current characteristics as shown by characteristic curves 130, 131, 132. For this reason, for example, when the welding arc voltage is given by the line segment 134, the difference between the current A 'during the welding operation and the current A when the welding rod is short-circuited becomes large. For example, the current A ₃ during welding rods shorted than the current A _'3 when operating under the characteristic curve 132 is such that approximately 2 times the value occurs. For this reason, a hole may be undesirably formed at that position due to a short circuit, and a crater may be undesirably generated.

Also as can be seen when compared to the characteristic curves 130 and 132, the no-load terminal voltage becomes to decrease as the voltage V ₃ at irrespective other contrast to being voltages V ₁ at. For this reason, when a small-diameter welding rod is used, the arcability of the welding point is poor. For this reason, it is difficult to perform welding with a reduced welding current.

For this purpose, the characteristic curves 135, 136, 13 shown in FIG.
As described in 7, it is desired to control so as to obtain a characteristic corresponding to constant current control. That FIG. 6 (B) 'between the ₃ and the point A _3, point A' the point A in the example between ₂ and point A _2, between the point A _'1 and point A _1, It is desired to control the current levels so that there is almost no difference between them.

[Means for solving the problem]

The present invention solves this problem by giving a constant current characteristic.

FIG. 1 is an explanatory diagram for explaining the concept of the present invention. In the figure, reference numeral 3 is a generator, 5 is an AC output winding, 6 is an exciting winding, 7 is a field winding, 8-1 and 8-2 are rectifier circuits, 9 is a rectifier for field, and 11- 1,
11-2 is an output line of a main power generation winding, 12-1 and 12-2 are thyristors (or thyristor groups), and 13 and 14 are changeover switches. This shows what is switched.

Although not shown, the thyristor group 12-1 and / or
Or 12-2 is to provide a reference voltage level determined corresponding to the load current, so that the conduction angle is controlled correspondingly (that is, to provide a constant current characteristic) and the output is controlled. Have been.

[Action]

The conduction angles of the thyristor groups 12-1 and / or 12-2 are controlled. In the case of the present invention,
As will be described later in detail, of the thyristors corresponding to the W-phase among the thyristors corresponding to the U-phase, V-phase, and W-phase, for example, the W-phase of the output line of the main power generation winding, for example, 11-1 During a period when the voltage is higher than the other phases, the conduction angle of the thyristor corresponding to the W phase is controlled so as to match the reference voltage level determined according to the load current.

Therefore, the reference voltage level (the reference voltage level for setting the current supplied by the first main power generation winding to a predetermined level corresponding to the first main power generation winding) is set to a desired level. Thyristor group 12
-1 are controlled so as to match each level. Then, by individually controlling the thyristor groups 12-1 and 12-2, it is possible to individually control the respective welding currents.

〔Example〕

FIG. 2 shows a configuration of an embodiment in which a thyristor corresponding to the W phase is controlled, and FIG. 3 shows waveforms for explaining the operation.

FIG. 2 shows, for simplicity, a case where there is only one main power generation winding and only one rectifier circuit. For simplicity, a configuration for controlling a W-phase thyristor is shown.

8-1, 11-1, and 12-1 in the figure correspond to FIG. Reference numeral 4 denotes a main power generation winding, and 12-1W denotes a thyristor corresponding to the W phase. 15 DC source, 16 denotes a DC source control circuit, 17 to 19 are each comparator 2 ₀ to 22 are each photo coupler, 23U, 23V, 23W are each thyristor control unit, 24
Is a transistor, 25 is a FET, 26-1 and 26-2 are voltage generators for setting a reference voltage level, 27 is a comparator, 28 is a photocoupler, and 29 is a capacitor.

The three-phase output from the main power generation winding 4 is converted to DC by the rectifier circuit 8-1. Then, by controlling the conduction angle of the thyristor 12-1, the DC output is controlled.
In the illustrated case, the control unit 23W for the thyristor 12-1W is shown for exclamation as described above.
Control units 23U and 23V similarly exist for the other U-phase and V-phase.

The comparators 17 to 19 compare the U-phase and _W- phase voltages on the output line 11-1 of the main power generation winding. That is, the comparator 17 is set low while the U-phase voltage is higher than the W-phase voltage. Comparator 18 is pulled low while the V-phase voltage is greater than the U-phase voltage. Then, the comparator 19 is made low while the W-phase voltage is higher than the V-phase voltage. The photo coupler output w- shown in FIG.
v (30) represents a period during which the comparator 19 is turned on and the photo coupler 22 shown in FIG. 2 is outputting an output.

While the photo coupler 22 is on, the transistor 24 is on and charges the capacitor 29 via the FET 25.
The waveform (31) of the capacitor shown in FIG. 3 represents the terminal voltage of the capacitor 29. Assuming that the reference voltage level set by the voltage generator 26-2 is the voltage level 32 as shown in FIG. 3, the comparator 27 is turned on as in the ON period 33 shown in FIG. Through,
Thyristor 12-1W is turned on. The thyristor 12 corresponds to the reference voltage level 32 corresponding to the load current.
The ON period of -1 W is controlled. That voltage at no load as FIG. 6 (B) is output such that the voltages V ₁ is controlled. Although the description is omitted, the same applies to the U phase and the V phase. The voltage of the voltage generator 26-2 is commonly used for controlling each phase.

Needless to say, the thyristor group 12-1 shown in FIG. 1 is similarly provided with the reference voltage level, and welding can be performed independently by the outputs from the two main power generation windings.

〔The invention's effect〕

As described above, according to the present invention, the output can be independently controlled from the plurality of main power generation windings. Further, the difference between the current A 'at the time of welding and the current A at the time of short-circuiting can be reduced without undesired reduction of the no-load voltage.

[Brief description of the drawings]

FIG. 1 is a conceptual explanatory diagram of the present invention, FIG. 2 is a diagram of an embodiment, FIG. 3 is a waveform diagram for explaining operation, FIGS. 4 and 5 are explanatory diagrams for explaining a conventional case, FIG. FIGS. 1A and 1B are explanatory diagrams for explaining a problem on which the present invention is based. In the figure, 3 is the generator, 4 is the primary generating windings, 5 A _C output winding, 8-1,8
2 is a rectifier circuit, 12-1 and 12-2 are thyristors (or thyristor groups), 17 to 19 are comparators, 23U and 23, respectively.
V and 23W represent thyristor controllers, respectively, and 12-1W represents a thyristor corresponding to the W phase.

Claims (1)

(57) [Claims] 1. A generator having at least two main generator windings for rectifying an induced voltage and supplying power to a load, wherein the generator is induced in at least one of the two main generator windings. A thyristor is provided for a rectifier circuit for rectifying a voltage, and a conduction angle of the thyristor is controlled, and a conduction angle of each of the thyristors included in the rectifier circuit is controlled for the at least one rectifier circuit. In doing so, the current level of the current supplied to the load is extracted, and a desired reference level that is in a relationship proportional to the current level is set based on the extracted current level. Obtaining a triangular wave voltage having a level proportional to the passage of time in each of the respective thyristors in the conductive period, and obtaining the voltage level of the triangular wave voltage and And comparing the quasi-level with the quasi-level to obtain a conduction angle with respect to each of the corresponding thyristors, wherein the power supply from the at least two main power generation windings to the load can be independently controlled. A power generator that can be individually powered.