JPH09121599A - Automatic voltage regulator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve responsiveness and stability, and to make it possible to maintain the good follow-up capability of a voltage setting device. SOLUTION: By feeding back each deviation ΔV41 , ΔV42 between each voltage detector 4a, 4b and each voltage setting device 5a, 5b to the voltage setting devices 5a, 5b, the follow-up capability of the voltage setting device 5a, 5b can be improved when the reciprocal driving of an automatic voltage regulator (AVR) IV, V is switched over. At the same time, by feeding back the output signal of a field current detector 13, the dual system of a field current minor loop corresponding to each AVR IV, V is added and also, an automatic follow-up circuit 16 is provided on both of the field current minor loops.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic voltage regulator, particularly in a power generation facility.
It is useful when applied to a case where one AVR system is duplicated and shockless switching is performed from one AVR system to the other AVR system.

[0002]

2. Description of the Related Art In power generation equipment, an AVR is usually provided in order to keep the terminal voltage of the generator at a predetermined value, but it is also proposed to duplicate this AVR in order to cope with the failure of this AVR. Has been done. The duplicated AVR is called a dual AVR.

FIG. 5 is a block diagram showing a conventional dual AVR.

In the figure, 1 is a synchronous generator, 1a is a field winding thereof, 2 is an AC exciter, 2a is a field winding thereof, D is a diode, and a field is provided by two systems of AVR I and II. Magnetic winding 2
a generated voltage (terminal voltage) of the synchronous generator 1 by controlling the field current I _f2 of a and further controlling the output voltage of the AC exciter 2 to control the field current I _f1 of the field winding 1 a. Is configured to control.

AVR I and II are transformers 3a and 3b, voltage detectors 4a and 4b, voltage setters 5a and 5b, and an adder 6, respectively.
a and 6b and the PI amplifiers 7a and 7b, the voltage comparison unit, the phase control units 8a and 8b, the rectifiers 9a and 9b formed by the thyristors Th, the switches 90A and 90B, and the contact A.
_{It has} a main circuit composed of ₁ and B ₁ and an auto follow circuit 10.

The switches 90A, 9 of the AVR I, II
0B is in a mutually opposite state, that is, when the switch 90A is closed, for example, the switch 90B operates so as to be in the open state so that only one of the AVR I and AVR II is operated. In addition, contact A ₁ is AVR
During operation I, contact B ₁ is closed during operation AVRII.

Thus, for example, when switch 90A is closed, AVR I is in the operating mode. That is,
Synchronous generator 1 detected by the transformer 3a and the voltage detector 4a
Obtains both of the deviation [Delta] V ₁₁ by the adder 6a compares the set voltage V _ref1 of the terminal voltage V ₁ and the voltage setting unit 5a, the voltage deviation signal [Delta] V ₂₁ by processing the deviation [Delta] V ₁₁ in the PI amplifier 7a To get

In the phase controller 8a, the voltage deviation signal ΔV ₂₁
Based on the above, the conduction angle of the thyristor Th of the rectifier 9a is controlled so that the voltage deviation signal ΔV ₂₁ becomes small.

Thus, the field current I _f2 of the AC exciter 2 is controlled to control the output voltage of the AC exciter 2, and the field current I _f1 based on this output voltage is controlled to control the synchronous generator 1. The power generation voltage of is automatically controlled to a constant value.

At this time, for the AVRII, the switch 9
Although 0B is opened and the output is cut off, each component is operating and the contact A ₁ is closed. Therefore, in this AVRII, the auto follow circuit 10 is used.
The voltage is adjusted by means of the above to realize shockless switching from AVR I to AVR II.

More specifically, the auto follow circuit 1
0 includes an adder 10a, an amplifier 10b, and an inverting amplifier 10
c, and the voltage deviation signal of AVR I and AVR II
ΔV _{twenty one}, ΔV_{twenty two}Deviation ΔV_ThreeAnd the deviation ΔV_ThreeBut
It is controlled to be small. Specifically, the deviation ΔV_Three
Is added to the adder 6b and the voltage setting device 5b is set.
It is added to the voltage.

Note that when the AVR I is at rest, the contact B ₁ is closed and the contact A ₁ is opened, so that the deviation Δ
V ₃ is added to the adder 6a and the set voltage of the voltage setter 5a.

FIG. 6 shows a manual voltage regulator (hereinafter referred to as MVR) using a voltage setting device 5c which is an adjustable resistor, which replaces the AVRII shown in FIG. In this figure, the same parts as those in FIG. 5 are denoted by the same reference numerals, and duplicate description will be omitted.

In the case of the configuration of FIG. 6, P of AVR I
The voltage deviation signal ΔV ₂₁ and MVR output from the I amplifier 7a
The voltage setting device 5c is increased or decreased according to the deviation ΔV ₃ from the setting voltage V ₀ which is the output of the voltage setting device 5c of III, and the deviation ΔV ₃ is controlled to be small.

In addition, during MVR III operation, phase control
The part 8b is the set voltage V of the voltage setting device 5. ₀Based on rectifier 9
Control b.

[0016]

Since the dual AVR I, II according to the prior art as described above has only the voltage measure loop, the responsiveness and stability are becoming insufficient.

Further, the voltage deviation signal ΔV ₂₁ which is the output signal of the PI amplifier 7a and the voltage deviation signal ΔV ₂₂ which is the output signal of the PI amplifier 7b are immediately balanced, but the voltage detection units 4a and 4b and the voltage setting unit are set. The balance with 5a and 5b is slow and causes a shock to the terminal voltage of the synchronous generator 1 when switching between AVR I and II.

The above-mentioned problems relating to responsiveness and stability and the point of causing shock at the time of switching are the same in the case shown in FIG.

In view of the above-mentioned prior art, it is an object of the present invention to provide an AVR which can improve the response and stability and can also keep the followability of the voltage setting device excellent.

[0020]

The structure of the present invention for achieving the above object is as follows. 1) A two-system voltage comparison unit that compares the set voltage value set in the voltage setter with the output voltage value of the generator detected by the voltage detection means to obtain the deviation between the two systems, and reduces the deviation. It has a main circuit that adjusts the field current of the generator and is shared by the voltage comparison units of the two systems, and selects the deviation of one of the voltage comparison units to adjust the field current. An automatic voltage configured to enable shockless switching between the voltage comparators by comparing the voltage deviation signals representing the deviations of the voltage comparators and feeding back the deviations of the two to the idle voltage comparators. In the adjusting device, the deviation between the output signal of the voltage setting device and the output signal of the voltage detecting means is calculated, and this deviation is fed back to the input side of the voltage setting device to reduce this deviation.
In the main circuit, a value based on a field current is fed back and compared with the voltage deviation signal, and control is performed so as to reduce the deviation between the two.

2) In 1), one of the voltage comparators is replaced by a manual voltage setting device, and the output signal of the manual voltage setting device is one voltage deviation signal.

3) The set voltage value set in the voltage setter,
Two systems including a voltage comparison unit that compares the output voltage value of the generator detected by the voltage detection means to obtain the deviation between the two, and a main circuit that adjusts the field current of the generator so that this deviation becomes small. Of the automatic voltage adjustment system, while the adjustment operation of one of the automatic voltage adjustment systems is stopped, the adjustment operation of the other automatic voltage adjustment system is stopped, and the voltage deviation signals representing the deviations of the respective automatic voltage adjustment systems are compared. In the automatic voltage regulator configured to enable shockless switching between the automatic voltage regulation systems by feeding back the deviation between the two, the output signal of the voltage setting device and the output signal of the voltage detection means A deviation is taken, and this deviation is fed back to the input side of the voltage setting device to control it so as to reduce this deviation. Feedback is performed to compare with the voltage deviation signal, and control is performed so as to reduce the deviation between the two, and the field current deviation signal representing the deviation of the voltage deviation signal of each automatic voltage adjustment system is compared to compare the deviation between the two. It is configured to enable shockless switching between automatic voltage adjustment systems by feeding back.

4) In 3), one of the voltage comparators should be replaced by a manual voltage setting device, and the output signal of this manual voltage setting device should be one voltage deviation signal.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing a first embodiment of the present invention. The present embodiment adds a field current minor loop and its auto-following circuit to the conventional technique shown in FIG. 5, and further includes a voltage detecting unit of a dormant AVR of two systems including a voltage comparing unit and a main circuit, respectively. The deviation between the output voltage and the output voltage of the voltage setting device is fed back to the input side of the voltage setting device, and this deviation can be held in advance to the minimum. Therefore, the same parts as those in FIG.

As shown in FIG. 1, in this embodiment, AVRI
At V and V, adders 11a and 11b and amplifier 12
a, 12b, field current detector 13, adders 14a, 14
b, PI amplifiers 15a and 15b, auto follow circuit 1
6 and contact A_Two, A_Three, B_Two, B _ThreeHas been added.

The adders 11a and 11b are voltage detectors 4a,
4b and the output signals of the voltage setters 5a and 5b are compared, and both are compared.
Deviation ΔV₄₁, ΔV₄₂Is what you want. This deviation
ΔV ₄₁, ΔV₄₂Is an amplifier 12a, 12b and a contact B_Two,
A_TwoFeed to the inlet side of the voltage setting device 5a, 5b via
Be backed. Contact B at this time_TwoIs driving AVR V
Contact point A again_TwoClosed during operation of AVR IV
It is.

As a result, the voltage setters 5a and 5b of the AVRIV, V at rest are set to the amplifiers 12a and 12 at the set voltage.
The deviations ΔV ₄₁ and ΔV ₄₂ amplified in b are added to obtain the deviation ΔV
₄₁ , ΔV ₄₂ is on standby with the minimum.

The field current detector 13 detects the field current I _f2 supplied to the AC exciter 2 and feeds back a value based on this field current I _f2 to the adders 14a and 14b. At this time, the PI amplifier 7 is added to the adders 14a and 14b.
voltage deviation signals ΔV ₂₁ , ΔV ₂₂ which are output signals of a and 7b
Has been supplied.

As a result, the voltage deviation in the adders 14a and 14b is
Difference signal ΔV_{twenty one}And field current I_f2Deviation from the value based on
V₅₁, ΔV₅₂And the deviation ΔV₅₁, ΔV₅₂The PI
After amplification by the pumps 15a and 15b, the phase control units 8a and 8
Deviation ΔV by supplying to b ₅₁, ΔV₅₂Is small
Field current I_f2Control. Thus, the field current
A minor loop is formed.

The auto-follow circuit 16 realizes shockless switching between AVR IV and V with respect to the field current minor loop, and the configuration itself is similar to that of the auto-follow circuit 10. That is, it has an adder 16a, an amplifier 16b, and an inverting amplifier 16c, and is a field current deviation signal ΔV which is an output signal of the PI amplifiers 15a and 15b.
The deviation ΔV ₇ between ₆₁ and ΔV ₆₂ is calculated, and the deviation ΔV ₇ is controlled to be small. At this time, the contact B ₃ is AV
The contact A ₃ is closed during the operation of R V and during the operation of AVR IV.

As a result, the value based on the deviation ΔV ₇ is added to the adders 14a and 14b of the AVR IV, V at rest, and the deviation ΔV ₇ is kept at the minimum value.

According to this embodiment, since the field current minor loop is added, the responsiveness and stability of the control of the terminal voltage of the synchronous generator 1 can be further improved.

The outputs of the voltage detectors 4a and 4b and the voltage setters 5a and 5b which are at rest are balanced in advance,
Since the field current minor loop is also provided with an auto-follow circuit, it is possible to more reliably switch the operation between AVRIV and V without shock.

FIG. 2 is a block diagram showing a second embodiment of the present invention. In this embodiment, MVR VI using a voltage setting device 5c which is an adjustable resistor replaces AVR V shown in FIG. 1, and a field current minor loop and its auto-following circuit are added to the conventional technique shown in FIG. In addition, the deviation ΔV ₄₁ between the terminal voltage V ₁ which is the output voltage of the voltage detection unit 4a of AVR V and the set voltage V _ref1 which is the output voltage of the voltage setting device 5a is fed back to the input side of the voltage setting device 5a. The deviation ΔV ₄₁ can be held in advance to the minimum.

In FIG. 2, those parts which are the same as those corresponding parts in FIGS. 1 and 5 are designated by the same reference numerals, and a duplicate description will be omitted.

FIG. 3 is a block diagram showing a third embodiment of the present invention. This embodiment is a P of AVR V shown in FIG.
The main circuit portion reaching the rectifier 9b after the I amplifier 15b is A
It has AVR VII and VIII which are shared with those of VRIV.

That is, in this embodiment, while only the voltage measure control system is designed to be duplicated, the parts related to the voltage detection units 4a and 4b, the voltage setters 5a and 5b, etc., which constitute the duplicated voltage comparison unit, are The configuration is similar to that shown in FIG.

In FIG. 3, those parts which are the same as those corresponding parts in FIG. 1 are designated by the same reference numerals, and a duplicate description will be omitted.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention. This embodiment is the P of AVRVI shown in FIG.
The main circuit portion reaching the rectifier 9b after the I amplifier 15b is A
It has the AVR VII and IX shared with the one of the VRIV, and at the same time, replaces the AVRVI shown in FIG. 3 with the MVRIX using the voltage setting device 5c which is an adjustable resistor.

In FIG. 4, those parts which are the same as those corresponding parts in FIGS. 2 and 3 are designated by the same reference numerals, and a duplicate description will be omitted.

[0042]

As described above in detail with the embodiments, according to the present invention, since the deviation between the voltage setting device and the voltage detecting means is fed back to the voltage setting device, the voltage setting device can be tracked. Get faster In addition, the addition of a field current minor loop improves stability and responsiveness.
At this time, automatic follow of AVR with field current minor loop is also possible.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a first embodiment of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a third embodiment of the present invention.

FIG. 4 is a block diagram showing a fourth embodiment of the present invention.

FIG. 5 is a block diagram showing an example of a conventional technique.

FIG. 6 is a block diagram showing another example of the conventional technique.

[Explanation of symbols] IV, V, VII, VIII AVR VI, IX MVR 1 Synchronous generator 1a Field winding 4a, 4b Voltage detector 5a, 5b, 5c Voltage setter 11a, 11b Adder 13 Field current detection Part 16 Auto follow circuit

Claims (4)

[Claims] 1. A two-system voltage comparing section for comparing the set voltage value set in the voltage setter with the output voltage value of the generator detected by the voltage detecting means to obtain the deviation between the two, and this deviation is small. So that the field current of the generator is adjusted and the main circuit shared by the voltage comparison sections of the two systems is used, and the deviation of either one of the voltage comparison sections is selected to adjust the field current. Further, by comparing the voltage deviation signals representing the deviations of the respective voltage comparison sections and feeding back the deviations of the two to the idle voltage comparison section, it is possible to perform shockless switching between the voltage comparison sections. In the automatic voltage regulator described above, the deviation between the output signal of the voltage setting device and the output signal of the voltage detecting means is calculated, and the deviation is fed back to the input side of the voltage setting device to reduce the deviation. And feedback values based on the field current in the road compared to the voltage deviation signal, the automatic voltage regulator, characterized by being configured to control so as to reduce the deviation between. 2. The automatic voltage generator according to claim 1, wherein one of the voltage comparators is replaced by a manual voltage setting device, and the output signal of the manual voltage setting device is one voltage deviation signal. Adjustment device. 3. A voltage comparing section for comparing the set voltage value set in the voltage setting device and the output voltage value of the generator detected by the voltage detecting means to obtain the deviation between the two, and for reducing this deviation. While having a two-system automatic voltage adjustment system including a main circuit for adjusting the field current of the generator, while the adjustment operation of one automatic voltage adjustment system, the adjustment operation of the other automatic voltage adjustment system is suspended, Further, in an automatic voltage adjusting device configured to enable shockless switching between the automatic voltage adjusting systems by comparing the voltage deviation signals representing the deviations of the respective automatic voltage adjusting systems and feeding back the deviations of the two. The deviation between the output signal of the voltage setting device and the output signal of the voltage detecting means is taken, and this deviation is fed back to the input side of the voltage setting device to control the deviation so as to reduce the deviation. In the main circuit of the adjustment system, a value based on the field current is fed back and compared with the voltage deviation signal, and control is performed so as to reduce the deviation between the two, and the voltage deviation signal of each automatic voltage adjustment system is controlled. An automatic voltage adjusting device characterized in that it is configured to enable shockless switching between automatic voltage adjusting systems by comparing field current deviation signals representing the deviations and feeding back the deviations of the two. 4. The automatic voltage generator according to claim 3, wherein one of the voltage comparators is replaced by a manual voltage setting device, and the output signal of the manual voltage setting device is one voltage deviation signal. Adjustment device.