JPH05284799A - Voltage regulator for generator - Google Patents

Abstract

PURPOSE:To obtain a voltage regulator for a generator in which an overshoot of an output at the time of starting the generator is suppressed and regulation is executed even if a combination test with a prime mover is not conducted. CONSTITUTION:An exciting current to a field winding 16 of a generator 1 is supplied after a rotating speed of a prime mover 2 is stabilized, an automatic voltage regulator 5 is controlled to a preset voltage previously set to a lower value than a rated voltage at the time of starting, and then switched to a rated voltage setting. Thus, an overshoot of an output voltage at the time of starting can be suppressed, an application of an overvoltage to a load apparatus is prevented, and a final regulation of the apparatus can be completed without waiting a combination test with the mover.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a generator voltage regulator for controlling an output voltage of a generator to a rated voltage.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing a conventional generator voltage regulator. In the figure, 1 is a generator, 2 is a prime mover for driving the generator, 3 is a transformer, 4 is an instrument transformer for detecting the output voltage of the generator 1, and 5 is an automatic voltage regulator (AV).
R), 6 are voltage setters, 7-10 are thyristors, detection circuits, comparison circuits and control circuits in the AVR 5, 13 is a battery, 14 is a contactor, 14A is a contactor 14
Is a main contact point, 19 is a contact point that closes when the prime mover 2 reaches the ignition speed, and 16 is a field winding of the generator 1. FIG. 4 is a time schedule of a conventional generator voltage regulator.
In the figure, 17 is a change in the rotation speed of the prime mover 2, and 18 is a change in the output voltage of the generator 1.

Next, the operation will be described. When the prime mover 2 is started and the ignition speed is reached, the contact 19 is closed, the contactor 14 is excited, and the main contact 14 of the contactor 14 is excited.
A is closed, the field winding 16 of the generator 1 is excited by the battery 13, and the output voltage of the generator 1 is generated. The output voltage of the generator 1 is stepped down by the transformer 3, the exciting current is further supplied to the field winding 16 of the generator 1 via the thyristor 7, and the output voltage of the generator 1 rises. In addition,
The exciting current supplied by the transformer 3 can be supplied only when the gate of the thyristor 7 housed in the AVR 5 is ON, and the output voltage of the generator 1 controls the gate of the thyristor 7 by the control circuit 10 of the AVR 5. , Controlled to keep the rated voltage. The AVR 5 detects the output voltage of the generator 1 by the instrument transformer 4, inputs it to the detection circuit 8 housed in the AVR 5, and compares the detected voltage with a reference voltage preset by the voltage setting device 6 And the difference is output to the control circuit 10. The control circuit 10 controls the supply of the exciting current from the transformer 3 by controlling the gate of the thyristor 7 according to the above difference, whereby the output voltage of the generator 1 is maintained at the rated voltage.

[0004]

Since the conventional generator voltage regulator is constructed as described above, the output voltage 18 of the generator 1 is set by the voltage setter 6 as shown in FIG. When the (normally rated voltage) is exceeded, the voltage suppression action starts, and when the rotational speed 17 of the prime mover 2 rises, the field winding 16 of the generator 1 is excited, so the prime mover 2
Since there is a possibility that it may overlap with the overshoot of the rotation speed of 17 above, there was a problem that the output voltage 18 of the generator 1 greatly overshoots the rated voltage. Further, since the rise of the output voltage of the generator 1 is influenced by the rise of the rotation speed of the prime mover 2, there is a problem that the final setting of the generator voltage regulator is not determined until a combination test with the prime mover 2 is performed. there were.

The present invention has been made to solve the above-mentioned problems, and suppresses overshoot of the output voltage of the generator 1 and tests the combination of the generator voltage adjusting device with the prime mover 2. It is an object of the present invention to obtain a generator voltage regulator that can be determined without waiting.

[0006]

The generator voltage regulator according to the present invention stabilizes the supply of the exciting current to the field winding of the generator at the rated rotation speed after the rotation speed of the prime mover overshoots. The automatic voltage regulator (AVR) controls the preset voltage to a preset voltage lower than the rated voltage in advance, and then switches to the rated voltage setting.

[0007]

According to the generator voltage regulator of the present invention, the exciting current is supplied to the field winding of the generator after stabilizing at the rated rotation speed, and at the time of starting, the automatic voltage regulator (AVR).
Among them, the preset voltage set lower than the rated voltage is controlled in advance, and then it is switched to the rated voltage setting.Therefore, the overshoot of the output voltage of the generator is not affected by the overshoot of the engine speed. It will be suppressed without receiving it, and the adjustment can be finally confirmed without waiting for the combination test with the prime mover.

[0008]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, the same parts as those in FIG. In FIG. 1, 11 is a preset circuit provided in the AVR 5 for giving a preset voltage to the comparison circuit 9, 14B is an auxiliary contact of the contactor 14, 12 is a detector for detecting that the prime mover 2 is stable at the rated speed, and 12A. Is a contact that is closed according to the detection of the detector 12, and 15 is a preset voltage of the output voltage of the generator 1.
Timer for resetting after 1 second, 15A is timer 1
Reference numeral 5 is a contact serving as a switching means that is opened at the time of counting up. In addition, 12 and 12A constitute a detecting means, and 3, 7, 10, 14, 14A and 14B constitute an exciting current supplying means. FIG. 2 is a time schedule of the generator voltage regulator according to the present invention, in which 17 is a change in the rotation speed of the prime mover 2 and 18 is a change in the output voltage of the generator 1.

Next, the operation will be described. After the start of the prime mover 2, when the detector 12 detects that the rotation speed 17 in FIG. 2 is stabilized at the rated rotation speed, the contact 12A is closed to excite the contactor 14 and the main contact 14 of the contactor 14 is excited.
The auxiliary contact 14B of the contactor 14 is closed at the same time as A is closed.
Also close. By closing the main contact 14A of the contactor 14, an exciting current is supplied to the field winding 16 of the generator 1 by the battery 13, and an output voltage of the generator 1 is generated. The output voltage of the generator 1 is stepped down by the transformer 3, and the exciting current is further supplied to the field winding 16 of the generator 1 via the thyristor 7. As a result, as shown in FIG.
Output voltage 18 rises to the preset voltage set by the preset circuit 11, and overshoots below the rated voltage and stabilizes at the preset voltage. After that, when T1 seconds have elapsed, the contact 15A of the timer 15 is opened and the operation of the preset circuit 11 is released. After that, the gate of the thyristor 7 is controlled so as to increase the supply of the exciting current to the set value of the rated voltage by the voltage setting device 6, the output voltage 18 of the generator 1 is raised to the rated voltage, and then the rated voltage is set. To be kept.

Embodiment 2. Although the preset voltage is set to one stage in the first embodiment, it is also possible to use several timers 15 and switch to several stages to prevent overshoot of the output voltage of the generator 1.

[0011]

As described above, according to the present invention, the exciting current is supplied to the generator after the rotation speed of the prime mover is stabilized, and at the time of starting, it is previously set in the automatic voltage regulator (AVR). The preset voltage set to a lower value is controlled by the rated voltage, and it is configured to switch to the rated voltage setting after a predetermined time, so it is possible to suppress overshoot of the output voltage of the generator and prevent overvoltage application to load equipment. At the same time, there is an effect such as improvement in workability that adjustment of the generator voltage adjusting device can be completed without waiting for a combination test with the prime mover.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a generator voltage regulator according to an embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a time schedule of the device.

FIG. 3 is a configuration diagram showing a conventional generator voltage regulator.

FIG. 4 is a characteristic diagram showing a time schedule of the device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 generator 2 prime mover 3 transformer (exciting current supplying means) 7 thyristor (exciting current supplying means) 9 comparison circuit 10 control circuit (exciting current supplying means) 11 preset circuit 12 detector (detecting means) 12A contact (detecting means) 14 Contactor (exciting current supply means) 14A Contactor main contact (exciting current supply means) 14B Contactor auxiliary contact (exciting current supply means) 15 Timer 15A Timer time limit contact (switching means)

Claims (1)

[Claims] 1. A comparison circuit compares a voltage detected from an output voltage of a generator driven by a prime mover with a set voltage, and controls an exciting current of the generator according to the difference.
In a generator voltage regulator that maintains the output voltage at the set voltage, a detection unit that detects that the prime mover is stable at a rated speed, and a preset lower than the set voltage based on the detection of the detection unit. A preset circuit for giving a voltage to the comparison circuit instead of the set voltage, an exciting current supplying means for supplying an exciting current to the generator according to the detection of the detecting means, and a fixed time period after the detecting means. A generator voltage adjusting device comprising: a timer for detecting progress and a switching means for switching a voltage applied to the comparison circuit from the preset voltage to the set voltage in response to detection by the timer.