JP2000184796A - Voltage switching device for engine generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a voltage switching device for engine generator formed so that circuit voltage to a simultaneous inspection lamp may be switched automatically without performing special work for parallel operation in the switching operation of a short-circuit plate. SOLUTION: This engine generator is provided with two sets of independent armature coils 1a, 1b and is formed so as to generate high voltage by serially connecting the circuit-shortening plate 3 of a voltage switching terminal board 2 with it and low voltage by parallelly connecting them with each other, wherein a simultaneous inspection lamp 6 for simultaneous input of parallel operation is connected through a resistor 7a from the voltage switching terminal board 2, and an electromagnetic relay 12 energized interlocking with a simultaneous switch 5 at the time of low voltage is provided. A relay contact 12s1 of the electromagnetic relay 12 is formed in parallel to the resistor 7a so as to energize the simultaneous inspection lamp 6 without use of the resistor 7a at the time of low voltage.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an engine generator, and more particularly to a voltage switching device for an engine generator capable of operating in parallel.

[0002]

2. Description of the Related Art Some AC engine generators, such as electric motors used, are capable of switching between two levels of low voltage (for example, 200 V) and high voltage (for example, 400 V) according to load. Widely used.

[0003] In this generator, as shown in FIG. 2, an armature coil of the generator 1 includes an inner coil 1a and an outer coil 1b.
The generated voltage is switched by rearranging the connection between the terminals by the voltage switching terminal plate 2, and when the inner coil 1a and the outer coil 1b are connected in series, the voltage becomes high, and the voltage becomes high. When connected, it is set to a low voltage.

That is, as shown in FIG.
b, the armature terminals X1, Y1, Z1 connected to the inner end of each of the outer coils 1b are respectively connected to the armature terminals U1, V1, W1 connected to the outer end of each of the outer coils 1b, and the respective inner coils. If U2, V2, and W2 connected to the outer end of 1a are respectively connected by the short-circuit plate 3 (FIG. 3A), the inner coil 1
a and the outer coil 1b are connected in parallel, and the armature terminal X
If 1, 1, Y1, Z1 and the armature terminals U2, V2, W2 are respectively connected by the short-circuit plate 3 (FIG. 3B), the inner coil 1a and the outer coil 1b are connected in series.

More specifically, as shown in FIG. 4, the armature terminals are arranged at equal intervals on the voltage switching terminal plate 2, and the short-circuit plate 3 is attached with a nut. FIG. 4 shows a case where the short-circuit plate 3 is assembled in a state of a low voltage. on the other hand,
When the load is large, a plurality of generators are operated in parallel to supply power, but this operation is performed by turning off the circuit breaker 10 and turning on the synchronous switch 5, and turning on the other generator. The circuit breaker 10 is turned on, and the speed control knob is operated while looking at the synchronization verification lamp 6 to turn on the circuit breaker 10 at the moment of synchronization.

The power source of the synchronous check lamp 6 is an armature terminal U
1, which is obtained directly from W1, and is directly connected when the voltage is low, and is connected via the resistor 7 when the voltage is high. In some cases, whether or not through the resistor 7 is provided by providing a changeover switch. However, if the operation of the changeover switch is forgotten, the synchronization check lamp 6 is damaged, and the synchronization work cannot be performed. Automatic switching is performed in conjunction with voltage switching work.

In this automatic switching, for example, an auxiliary terminal 8 is provided between the armature terminals U1 and U2 and W1 and W2 of the voltage switching terminal plate 2, and when the voltage is high, the synchronous check lamp 6 is connected to the armature terminal. When the voltage is switched from U1 and W1 via the resistor 7 and the voltage is switched to the low voltage by the short-circuit plate 3, the current is directly supplied from the auxiliary terminal 8 without the resistor 7.

[0008]

However, since the auxiliary terminal 8 has a small diameter (see FIG. 4), when the auxiliary terminal 8 is engaged with the short-circuit plate 3 and fastened, the auxiliary terminal 8 often bends or breaks the screw. there were. In addition, since the voltage switching and the parallel operation are not required at the same time, it is necessary to check the attachment state of the auxiliary terminal during the parallel operation.

In view of the above, the present invention provides a voltage switching of an engine generator in which the circuit voltage to the synchronous check lamp is automatically switched without performing a special operation for the parallel operation in the switching work of the short-circuit plate. It is intended to provide a device.

[0010]

Means for Solving the Problems To achieve the above object, the following means is adopted in the voltage switching device for an engine generator according to the present invention. That is, in an engine generator having two independent sets of armature coils and connecting a short-circuiting plate of a voltage switching terminal plate in series to generate a high voltage and connecting in parallel to generate a low voltage, a parallel operation is performed. A synchronous check lamp for synchronous input is connected from the voltage switching terminal plate via a resistor, an electromagnetic relay that is excited in conjunction with the synchronous switch at low voltage is provided, and a relay contact of the electromagnetic relay is connected to the resistor. It is provided in parallel so that at the time of low voltage, the synchronous check lamp is energized without passing through the resistor.

The present invention is applied to an AC generator driven by an engine that can switch a generated voltage between a high voltage and a low voltage and that can perform parallel operation. In addition, the switching of the generator voltage is performed by changing the connection of each armature terminal with a short-circuit plate with a voltage switching terminal plate provided with armature terminals connected from the outer coil and the inner coil of the generator, thereby connecting the outer coil to the outer coil. The operation is performed by setting the inner coil in series or in parallel, and is applied to a case where the synchronous operation of the parallel operation is performed while watching the synchronous check lamp. Therefore, an engine generator provided with an automatic parallel operation device capable of automatically performing parallel operation is not targeted.

A synchronous check lamp required for the synchronous turning on of the parallel operation is connected via a resistor from an armature terminal of the voltage switching terminal plate, and this armature terminal is connected to the outer end (output) of the outer coil of the generator. Line side). The three-phase generator has three points U1, V1, and W1, but may be connected to any of them.

[0013] The above-mentioned "electromagnetic relay which is excited in conjunction with the synchronous switch at the time of low voltage" means that the electromagnetic relay does not operate at the time of high voltage.
This means a configuration in which auxiliary contacts and electromagnetic relays that open and close in conjunction with a synchronous switch are provided in a wiring connecting the inner end (X1) of the outer coil of the generator to the outer end (U2) of the inner coil.

Therefore, when the generators are set to a high voltage and are operated in parallel, the electromagnetic relay is not excited even when the auxiliary contact of the synchronous switch is turned on. It is energized through a resistor. on the other hand,
When the generator is set to low voltage and operates in parallel, the auxiliary switch is turned on by turning on the synchronous switch, and the electromagnetic relay is excited. As a result, the relay contact provided in parallel with the resistor is turned on, and the synchronous check lamp is energized without passing through the resistor.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. The connection circuit between the generator 1 and the voltage switching terminal plate 2 is the same as that shown in FIG. That is, the voltage switching of the generator 1 is performed by connecting the armature terminals X1, Y1, Z1 connected to the inner ends of the respective outer coils 1b to the respective Os with the short-circuit plate 3, and connecting the armature terminals X1, Y1, Z1 to the outer ends of the respective outer coils 1b. The armature terminals U1, V1, W1 and U2, V2, W2 connected to the outer ends of the respective inner coils 1a are respectively connected to the short-circuit plate 3
And the armature terminals X1 and Y
1, Z1 and the armature terminals U2, V2, W2 are connected to each other by the short-circuit plate 3 to obtain a high voltage (400V).

The synchronous check lamp 6 is connected to the armature terminal U1.
Through a resistor 7a, and a relay contact _12S1 is provided in parallel with the resistor 7a. Further, from the armature terminal W1, resistors 7b and 7c are connected in series and connected to the synchronous switch 5, and a relay contact _12S2 is provided in parallel with the resistor 7b.

The inner end of the outer coil 1b of the generator (X
From 1) to the outer end (U2) of the inner coil 1a, an auxiliary contact 5s that opens and closes in conjunction with the synchronous switch 5 and an electromagnetic relay 12 are provided in series. When the electromagnetic relay 12 is excited, the relay contacts 12 _S1 and 12 _S1
S2 is turned ON.

With such a configuration, the armature terminals U1, V1, W1 and the armature terminals U
2, V2, and W2 are connected by the short-circuit plate 3 (the state of FIG. 3A), and when the parallel operation is performed in a low voltage state,
When the synchronous switch 5 is turned on, the auxiliary contact 5s is turned on, the electromagnetic relay 12 is excited, and both the relay contact 12 _S1 and the relay contact 12 _S2 are turned on. _Power is supplied through 12 _S1 . On the other hand, the armature terminals X1, Y1, Z1 and the armature terminals U2, V2, W2 are connected by the short-circuit plate 3 (FIG. 3).
When the parallel operation is performed in the high voltage state (state (b)), the auxiliary contact 5s is turned on by turning on the synchronous switch 5, but the electromagnetic relay 12 is not excited, and the relay contact 12 _S1 and the relay Since the contact 12 _S2 remains OFF, the synchronous check lamp 6 is energized from the armature terminal U1 through the resistor 7a.

[0019]

As described above, according to the present invention, the synchronous check lamp used for the synchronous turning on of the parallel operation is connected from the voltage switching terminal plate via the resistor, and interlocks with the synchronous switch when the voltage is low. And a relay contact of the electromagnetic relay is provided in parallel with the resistor so as to energize the synchronous check lamp without passing through the resistor when the voltage is low. When the power generation voltage is switched by rearranging the circuit, the circuit voltage to the synchronous check light is automatically switched, and the switching work of the short-circuit plate can be performed regardless of whether the generators are operated in parallel or not. There is no need to do any special work. Therefore, there is no problem that the voltage of the synchronous check lamp circuit is checked or the auxiliary terminal is damaged unlike the related art.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an example of an engine generator switching device according to an embodiment of the present invention.

FIG. 2 is a circuit diagram of a conventional engine generator switching device.

3A and 3B are switching connection diagrams of the voltage switching terminal plate, in which FIG. 3A shows a low voltage state and FIG. 3B shows a high voltage state.

FIG. 4 is a plan view and a front view showing a specific example of the voltage switching terminal plate 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Generator 1a ... Inner coil 1b ... Outer coil 2 ... Voltage switching terminal board 3 ... Short circuit board 5 ... Synchronous switch 5s ... Auxiliary contact 6 ... Synchronous check lamp 7a, 7b, 7c ... Resistance 8 ... Auxiliary terminal 10 ... Breaker 12: Electromagnetic relay 12 _S1 , 12 _S2 : Relay contact 14: Resistance

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5G060 AA05 AA08 BA02 CA11 CB06 DA03 5H590 AA08 CA07 CC01 CC18 CC24 CC32 CC34 DD23 EA07 EA14 FC21 FC25 GA02

Claims (1)

[Claims] 1. An engine generator comprising two independent sets of armature coils, wherein short-circuit plates of voltage switching terminal plates are connected in series to generate a high voltage, and connected in parallel to generate a low voltage. A synchronous check lamp for synchronously turning on the parallel operation is connected from the voltage switching terminal plate via a resistor, an electromagnetic relay that is excited in conjunction with the synchronous switch at low voltage is provided, and a relay contact of the electromagnetic relay is connected. A voltage switching device for an engine generator, wherein a current is supplied to a synchronous check lamp without the intervention of a resistor when the voltage is low, provided in parallel with the resistor.