JPH0576280B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic voltage regulator for a generator for controlling the output voltage of the generator to a predetermined value.

[Prior Art] Fig. 4 is a schematic configuration diagram showing a conventional automatic voltage regulator for a generator.
3 is a potential transformer (PT) that detects the output voltage of generator 1; 4 is a voltage transformer (PT) that detects the output voltage of generator 1; and 4 compares the output voltage of generator 1 with a predetermined value (reference voltage) and detects the deviation between these voltages. 5 is an ignition device that generates a pulse in accordance with the output of the voltage deviation detection circuit 4; 6 is an ignition device 5;
7 is an auxiliary generator (PMG) as a power source for the rectifier 6, and 8 is a field breaker that opens and closes the excitation line of the exciter 2. be.

And these exciter 2, voltage transformer 3,
The output voltage is controlled by controlling the field current of the generator 1 based on the output voltage of the generator 1 using the voltage deviation detection circuit 4, the ignition device 5, the rectifier 6, the auxiliary generator 7, the field circuit breaker 8, etc. An automatic voltage regulator (AVR) is configured to automatically control the voltage to a predetermined value.

In addition, in recent years, the voltage deviation detection circuit 4 and the ignition device 5 are composed of multiple electronic circuits due to diversification of functions and improvement of characteristics and accuracy. Often printed on cards.

Next, the operation will be explained. Now, in order to control the output voltage of the generator 1, it is sufficient to control the field current of the generator 1, and for this purpose, the amount of excitation of the exciter 2 is controlled. First, the terminal voltage detected by the instrument transformer 3 is compared in the voltage deviation detection circuit 4 with a predetermined reference voltage from a reference voltage source built into the voltage deviation detection circuit 4, and the voltage difference between these voltages is The difference value is amplified and this difference output is then output to the ignition device 5. The ignition device 5 generates an ignition pulse according to the output from the voltage deviation detection circuit 4 and outputs it to the rectifier 6 as a trigger signal. The rectifier 6 that receives the ignition pulse supplies an output corresponding to the ignition pulse to the exciter 2, which changes the field current of the generator 1 and automatically adjusts the output voltage of the generator 1 to a predetermined reference voltage. It is something that is controlled.

[Problems to be Solved by the Invention] However, since such conventional automatic voltage regulators for generators are configured as described above, in the event that the automatic voltage regulator malfunctions, automatic voltage regulators cannot be used. In addition to the problem that the output voltage of the generator 1 cannot be controlled to a predetermined value, the voltage deviation detection circuit 4 and the ignition device 5 are complicated electronic circuits. Because these components are configured on printed cards, maintenance personnel have to measure and judge the signals of each circuit section in order to find these failure points, which can lead to long-term generator shutdowns. There is a risk that the stable supply of electricity will be disrupted.

This invention was made to solve the above-mentioned problems, and includes multiple series of automatic voltage regulators, which monitors the operating signals of each part of the automatic voltage regulators and is on standby in the event of an abnormality such as a failure. An object of the present invention is to obtain an automatic voltage regulator for a generator, which enables stable power supply control without changing the output voltage of the generator by switching to the automatic voltage regulator side of the generator. purpose.

[Means for Solving the Problems] In order to achieve the above object, the present invention has a plurality of automatic voltage regulators for generators, and each automatic voltage regulator has a plurality of cards mounted with electronic circuits. Prepare,
For each card, a comparator inputs its output signal as a monitor signal, compares it with a reference signal, and outputs an abnormal signal indicating that the card is abnormal when the deviation exceeds a predetermined value, and a characteristic function of the corresponding card. and a calculation unit that stores the input signal in advance and branches the input signal to the card, and the calculation unit includes a monitor circuit that generates the reference signal of each of the cards, and the card of one automatic voltage regulator and A circuit that compares the output of the corresponding card of the other automatic voltage regulator and outputs a mismatch signal if there is a difference between the two, and generates the abnormal signal when this mismatch signal and the above abnormal signal are received. The configuration is equipped with a switching circuit that selects the automatic voltage regulator on the side that is not installed.

[Function] In the automatic voltage regulator for a generator according to the present invention, one of the plurality of automatic voltage regulators:
The generator output voltage is automatically adjusted to a predetermined value, and at this time, the automatic voltage regulator monitor circuit detects the activation signal of the automatic voltage regulator. When an abnormality in the automatic voltage regulator is detected by this automatic voltage regulator monitor circuit,
Can be switched to voltage regulation mode by other automatic voltage regulators. This in turn causes the voltage to continue to be regulated by this other automatic voltage regulator.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing an automatic voltage regulator for a generator as an embodiment of the present invention. In FIG. 1, 12 is an automatic voltage regulator for system A, and 13 is an automatic voltage regulator for system B. The automatic voltage regulator 12 is composed of a voltage transformer 3A, a voltage deviation detection circuit 4A, an ignition device 5A, and a rectifier 6A.
B, a voltage deviation detection circuit 4B, an ignition device 5B, and a rectifier 6B.

In addition, 9 is an automatic voltage regulator 12 of A system and B
A monitoring device as an automatic voltage regulator monitor circuit that monitors the operating status of each hardware part in the automatic voltage regulator 13 of the system, 10 is an individual display pulse that individually displays a failure point, 14A, 14B is a monitoring device 9 This is the fault detection output line from.

Furthermore, 25 is a changeover switch built into the monitoring device 9, and when an abnormality is detected in the automatic voltage regulator 13 of the B system, the changeover switch 25 switches to the a terminal side. 12, while automatic voltage regulator 1 of system A
When abnormality No. 2 is detected, the voltage is switched to the b terminal side and the voltage is adjusted by the automatic voltage regulator 13 of the B system. That is, when the changeover switch 25 detects an abnormality in the automatic voltage regulator,
A switching circuit is configured to switch to a voltage regulation mode using another normal automatic voltage regulator.

By the way, FIG. 2 is a block diagram showing the internal configuration of a voltage deviation detection circuit and a monitoring device in an automatic voltage regulator for a generator as an embodiment of the present invention. In FIG. 2, 21A and 23A are The circuit portions 21B and 23B are printed cards forming the voltage deviation detection circuit 4A, and the circuit portions 21B and 23B are printed cards forming the voltage deviation detection circuit 4B. Further, 17A and 17B are calculation units, respectively, and the calculation unit 17A is the voltage deviation detection circuit 4.
A pseudo output signal is generated from the circuit portion 21A by receiving the input signal 15A to the circuit portion 21A and performing calculations in consideration of the characteristic function of the circuit portion 21A. A pseudo output signal of the circuit section 21B is generated by receiving the input signal 15B to the circuit section 21B and performing calculations in consideration of the characteristic function of the circuit section 21B.

18A and 18B are comparison sections, and the comparison section 18A is
Pseudo output signal from calculation section 17A and circuit section 21
Upon receiving the actual output signal 16A from A, the signal difference between these signals exceeds a predetermined value. In other words, if an imbalance occurs between both signals, it is considered an abnormality and the fault signal is ANDed.
It is output to the gate 19A, and the comparison section 18B
receives the pseudo output signal from the calculation section 17B and the actual output signal 16B from the circuit section 21B, and when the difference between these signals exceeds a predetermined value, that is, when an imbalance occurs between the two signals, it is regarded as abnormal. , fault signal
It is output to AND gate 19B.

Reference numeral 20 denotes a comparison section, which receives the outputs 16A and 16B from the circuit sections 21A and 21B, and when the difference between both outputs 16A and 16B exceeds a predetermined value, the comparison section 20 passes the mismatch signal 22 to AND gates 19A and 19.
This is what is output to B.

Note that the AND gates 19A and 19B are the comparison section 2.
If a fault signal is received from the comparator 18A or 18B while receiving the mismatch signal 22 from 0, the fault detection signal is sent to the fault detection output lines 14A, 14B.
Output to. At this time, this signal is also output to the changeover switch 25, and if it receives a failure detection signal from the AND gate 19A, the changeover switch 25 will
If there is no abnormality in the automatic voltage regulator 13 of the B system and an abnormality occurs in the operating state of the generator 1, the changeover switch 25 switches to the b terminal side and receives a failure detection signal from the AND gate 19B.
If there is no abnormality in the A-system automatic voltage regulator 12 and an abnormality occurs in the operating state of the generator 1, the voltage is switched to the a terminal side.

By the way, in the above, the circuit portion 21A,
Although failure detection regarding circuit 21B has been described, failure detection regarding other circuits 23A, 23B, etc. is also performed using the same configuration and procedure.

Next, the operation will be explained. Assume now that the changeover switch 25 is on the a terminal side and voltage adjustment is being performed by the A-system automatic voltage regulator 12.
At this time, operating signals of each component of the automatic voltage regulators 12 and 13 are input to the monitoring device 9.
Here, as an example, a description will be given focusing on certain circuit parts 21A and 21B that constitute the voltage deviation detection circuit 4. That is, the input signal 15 to the circuit portion 21A
A is input to the calculation section 17A, and the pseudo output signal of the circuit section 21A is output from the calculation section 17A to the comparison section 18A, and the actual output signal 16A from the circuit section 21A is also input to the comparison section 18A. The abnormality of the circuit section 21A is monitored by the section 18A. On the other hand, the input signal 15B to the circuit section 21B is input to the calculation section 17B, and the input signal 15B is input to the calculation section 17B.
The pseudo output signal of the circuit section 21B is outputted from B to the comparison section 18B, and the actual output signal 16A from the circuit section 21B is also input to the comparison section 18B, and the comparison section 18B monitors the abnormality of the circuit section 21B. ing.

Also, the circuit portions 21A and 21B are connected to the comparison section 20.
Output signals 16A and 16B from are input.

By the way, suppose that the A-system automatic voltage regulator 12, particularly the circuit portion 21A that constitutes the voltage deviation detection circuit 4A, has failed. Then, in the comparator 20, a difference occurs in the signal levels from the circuit parts 21A and 21B, and as a result, a mismatch signal 22 is output from the comparator 20.
It is output to AND gates 19A and 19B. Also, a fault signal is sent from the comparison section 18A to the AND gate 19.
Since it is output to A, this causes AND gate 1
A failure detection signal is output from 9A. the result,
If an abnormality occurs in the operating state of the generator 1 under the condition that there is no abnormality in the automatic voltage regulator 13 of the B system, the selector switch 25 is switched to the b terminal side, and the automatic voltage regulator 12 of the A system is switched to the b terminal side. At the same time as being disconnected, the B-system automatic voltage regulator 13 is activated. Therefore, voltage adjustment is now performed by the automatic voltage regulator 13. At this time, the changeover switch 25 is switched simultaneously with the detection of an abnormality in the A-system automatic voltage regulator 12, so that the voltage regulation function can be continued without interruption.

Further, at this time, a signal indicating that the circuit portion 21A of the voltage deviation detection circuit 4A has failed is also output to the individual display panel 10, so the individual display panel 10
An indication to that effect will be made. This allows maintenance personnel to remove the circuit portion 21A and replace it with a new print card.

If a failure occurs next in the circuit portion 21B of the voltage deviation detection circuit 4B in the B-system automatic voltage regulator 13, the changeover switch 25 will be switched to the a terminal side in the same manner as described above, and
The individual display panel 10 displays a message to that effect.

Of course, the A and B system automatic voltage regulators 12 and 1
Even when the other circuits that make up 3 fail,
Similarly, the changeover switch 25 is changed over, and a display to that effect is made on the individual display panel 10.

The switching logic between the A-system automatic voltage regulator 12 and the B-system automatic voltage regulator 13 by the changeover switch 25 is shown in FIG.

That is, when the monitoring device 9 detects a failure in the A system, if there is no abnormality in the hardware of the B system and an abnormality occurs in the operating state of the generator 1, switching from the A system to the B system is performed. It can be done. In addition, when switching from system B to system A, the condition is that a failure in system B is detected, and if there is no abnormality in the hardware of system A and an abnormality occurs in the operating state of the generator, The system is switched from the A system to the A system.

Of course, at this time, as mentioned above, the monitoring device 9
Each fault location detected is displayed individually.

In the above embodiment, the exciter 2 is a brushless exciter, but it may be a thyristor exciter or a DC exciter, and the same effects as in the above embodiment can be obtained.

In addition, three or more series of automatic voltage regulators are installed, and one
The voltage may be adjusted by the automatic voltage regulators in the series, and the automatic voltage regulators in the remaining series may be used as standby automatic voltage regulators.

[Effects of the Invention] As described above, according to the present invention, a plurality of automatic voltage regulators are arranged in series, and a signal outputted by the card is adjusted for each card of a large number of cards constituting each of the automatic voltage regulators. In addition to providing a monitor circuit for detection, an automatic voltage regulator switching circuit is also provided to switch to voltage regulation mode using another automatic voltage regulator when an abnormality in the card is detected by the monitor circuit, thereby ensuring a stable power supply. In addition to increasing the reliability of the power supply system, failure locations can be easily and early discovered, and maintenance time can be significantly shortened.

[Brief explanation of drawings]

1 to 3 show an automatic voltage regulator for a generator as an embodiment of the present invention. FIG. 1 is a block diagram thereof, and FIG. 2 is an internal configuration of its voltage deviation detection circuit and monitoring device. FIG. 3 is a block diagram for explaining the switching logic by the switching circuit, and FIG. 4 is a block diagram showing a conventional automatic voltage regulator for a generator. In the figure, 1... Generator, 2... Brushless exciter, 3A, 3B... Instrument transformer, 4A, 4
B... Voltage deviation detection circuit, 5A, 5B... Ignition device, 6A, 6B... Rectifier, 7... Auxiliary generator,
8... Field circuit breaker, 9... Monitoring device, 10... Individual display panel, 12, 13... Automatic voltage regulator,
17A, 17B... Calculation section, 18A, 18B...
Comparison section, 19A, 19B...AND gate, 20
...Comparison section, 21A, 21B, 23A, 23B...
...Circuit part, 25...Selector switch. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.

Claims (1)

[Scope of Claims] 1. A generator has a plurality of automatic voltage regulators, each automatic voltage regulator is equipped with a plurality of cards mounted with electronic circuits, and each card outputs its output signal as a monitor signal. A comparator that outputs an abnormal signal indicating that the card is abnormal when the deviation exceeds a predetermined value when compared with a reference signal, and a comparator that stores the characteristic function of the corresponding card in advance and inputs the input signal to the card. and a calculation unit that performs branch input, and the calculation unit includes a monitor circuit that generates the reference signal of each of the cards, and outputs of the card of one automatic voltage regulator and the corresponding card of the other automatic voltage regulator. A circuit that compares the two and outputs a mismatch signal if there is a difference between the two, and when receiving this mismatch signal and the above abnormal signal, selects the automatic voltage regulator that does not generate the abnormal signal. An automatic voltage regulator for a generator, characterized by comprising a switching circuit.