JPH06259155A - Automatic voltage/reactive power controller - Google Patents

Abstract

PURPOSE:To ensure the stable automatic voltage/reactive power control with no divergent nor hunting phenomenon caused between the automatic voltage/ reactive power controllers. CONSTITUTION:A local controller 12 collects and outputs the drive information on the tap switches of each transformer 2 and those information on the voltage, the current, the active power and the reactive power on a power system. Then the controller 12 is prepared for each transformer 2 that has a function to manually operate the tap switch when a general controller 11 is excluded. The controller 11 is used in common to the transformers 2 which perform the general control of each tap switch to secure a cooperative operation among those transformers 2 based on the characteristic data on the generators 1 and each equipment of transformers 2, the central feeding command center information, the tap switch drive information received from each controller 12, and the information on the voltage, the current, the active power and the reactive power respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tap changer (hereinafter referred to as a tap changer) provided in each transformer for system voltage and reactive power of a power system in which a plurality of generators are connected via a plurality of transformers. , LTC) to control within the target range by switching taps, especially stable voltage reactive power control without divergence or hunting phenomenon between the voltage / reactive power control devices. The present invention relates to an automatic voltage / reactive power control device that can be performed.

[0002]

2. Description of the Related Art A conventional voltage / reactive power control device gives a drive command to an LTC provided in a transformer and adjusts a tap of the transformer to thereby obtain a system voltage or reactive power on the secondary side of the transformer. Is controlled within a desired range.

FIG. 2 is a block diagram showing a configuration example of a power system to which this type of voltage / reactive power control device is applied.
The voltage / reactive power control device shown in FIG. 2 is individually provided in each transformer of the power system, and individually controls the LTC of the transformer.

In FIG. 2, a generator 1 is connected to a power system via a transformer 2. The transformer 2 has an LTC (not shown). The voltage and current of the power system, which is the secondary side of the transformer 2, are extracted by an instrument transformer (hereinafter referred to as PT) 3 and an instrument current transformer (hereinafter referred to as CT) 4, respectively. Is input to the transducer 5.

In the transducer 5, the reactive power of the power system is obtained based on the input voltage and current of the power system. The reactive power Q representing the reactive power of the power system is obtained as the system voltage V representing the voltage of the power system. Is output together with. The reactive power Q and the system voltage V are input to the voltage / reactive power control unit 6 as process signals.

When the system voltage V and the reactive power Q deviate from the preset range for a certain time or longer, the voltage / reactive power control unit 6 outputs a command to increase or decrease the LTC tap of the transformer 2 to transform the voltage. The control calculation is performed so that the system voltage V and the reactive power Q on the secondary side of the device 2 are always within the target range. Next, the control operation of the voltage / reactive power control in the voltage / reactive power control unit 6 will be described in detail with reference to FIG.

In FIG. 3, the system voltage signal V and the reactive power signal Q, which are process signals, are input to the dead zone setting section 7. In the dead zone setting section 7, for example, the dead zone is set as shown in FIG. 4, and when the system voltage V and the reactive power Q exist in the shaded area in FIG. 4, the output of the dead zone setting section 7 is zero. . Further, if either or both of the system voltage V and the reactive power Q fluctuate and exist outside the shaded area, a signal of a level proportional to the size outside the shaded area, It is input from the dead zone setting unit 7 to the integrator 8.

The integrator 8 has an inverse time characteristic depending on the magnitude of the output signal of the dead zone setting section 7, that is, the integration time is shortened for an output signal of a large level, and for an output signal of a small level. Then, the obtained positive or negative direction signal is output by increasing the integration time.

When a reset signal is given to the integrator 8, the integrated value is cleared. For example, a timer (not shown) is provided in order to prevent the LTC from being continuously driven when the dead band output is zero or when tap driven by the LTC, and a reset signal supplied from this timer is provided. Locks the integral action. When the time longer than the set time set by the timer has elapsed since the tap of the LTC was driven last time,
The timer counts up, and the reset signal disappears depending on the presence or absence of the dead zone output signal.

On the other hand, when the system voltage V and the reactive power Q exceed the dead zone setting range and the level of the positive direction signal output from the integrator 8 reaches or exceeds the setting value of the increasing direction detection comparator 9, the increasing direction is increased. The detection comparator 9 generates a tap-up command indicating that the tap of the transformer 2 should be raised.

Further, when the level of the negative direction signal output from the integrator 8 reaches or exceeds the set value of the down direction detection comparator 10, the down direction detection comparator 10 indicates that the tap of the transformer 2 should be lowered. Generate a tap down command.

Further, if the output of the dead zone setting section 8 becomes zero before the output of the integrator 8 reaches the operation level of the increasing direction detecting comparator 9 and the decreasing direction detecting comparator 10, the reset signal causes the integrator 8 to operate. Output becomes zero and the control calculation returns to the initial state.

By the way, in the conventional automatic voltage / reactive power control device, the above-mentioned voltage / reactive power control device is individually provided for each transformer, and the LT of the transformer 2 in charge of each is independently provided.
By giving a drive command to C, the system voltage and reactive power on the secondary side of the transformer 2 are controlled.

Therefore, the voltage difference at each system point due to the power system power flow and system impedance distribution, each voltage
Dead band setting error of reactive power control device, PT3, CT
4 and due to detection / conversion errors in the transducer 5, a plurality of voltage / reactive power control devices installed near each other in the power system interfere with each other, and in some cases, divergence or hunting phenomenon occurs and control becomes impossible. May be. FIG. 5 and FIG. 6 are diagrams showing an example in which the divergence phenomenon between the main transformer in the power plant and the transformer in the substation in the voltage reactive power control on the power plant side and the substation side is reproduced by simulation.

[0015]

As described above, in the conventional automatic voltage / reactive power control device, stable voltage / reactive power control cannot be performed due to divergence or hunting phenomenon between the voltage / reactive power control devices. There was a problem.

An object of the present invention is to provide an extremely reliable automatic voltage / reactive power control device capable of performing stable voltage reactive power control without divergence or hunting phenomenon between the voltage / reactive power control devices. To do.

[0017]

In order to achieve the above object, the present invention provides a system voltage and a reactive power of a power system in which a plurality of generators are connected via transformers, respectively.
In the automatic voltage / reactive power control device that controls within the target range by switching the taps of the tap changer installed in each transformer, the drive information of the tap changer and the voltage, current, active power, and reactive power of the power system. A local controller provided for each transformer that has the function of collecting and outputting power information and manually operating the tap changer when the integrated control device is excluded, and device characteristic data of the generator and transformer Based on the information on the central power supply command center and the tap changer drive information from each local control device, voltage, current, active power, and reactive power information, the tap switch operation can be coordinated between the transformers. As is done, it is configured to include an integrated control device that is commonly provided to each transformer that integrally controls each transformer tap changer.

[0018]

Therefore, in the automatic voltage / reactive power control device according to the present invention, one integrated control device is provided in common for a plurality of transformers, and the integrated control device has device characteristic data and control for each generator and transformer. The voltage and current information of the target system, active power calculated from this voltage and current, reactive power information, tap changer drive information, central power supply command center information are concentrated, and the divergence between tap changers of each transformer or By determining the presence or absence of the hunting phenomenon and operating the tap changers in a coordinated manner, stable voltage / reactive power control can be performed.

[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings. FIG. 1 shows an automatic voltage
It is a block diagram which shows the structural example of a reactive power control apparatus. The same elements as those in FIG. 2 are designated by the same reference numerals.

In FIG. 1, a plurality of generators 1 are connected to a power system via a plurality of transformers 2. Each of the transformers 2 has an LTC (not shown),
The LTC is driven by the LTC driver 13 and its L
The TC drive information is transmitted to the local control device 12.

Further, the local control device 12 is provided for each transformer 2, extracts the voltage and current information of the power system which is the control target of the automatic voltage reactive power by PT3 and PT4, respectively, and further extracts this voltage, Based on the current information, the power stored inside and the active power with the reactive power transducer,
Reactive power information is obtained, and each of these pieces of information is output to the LTC drive device 1.
It has a function of outputting to the integrated control device 11 together with the LTC drive information from 3, and a function of manually operating the LTC when the integrated control device 11 is excluded.

Further, the integrated control device 11 is provided with each transformer 2
Common to each of the generators, the device characteristic data of the transformer 2 is input in advance, and the central power feeding command information, and the LTC drive information from each local control device 12, voltage, current, active power, invalid Based on each electric power information, the LTC of each transformer 2 is centrally controlled so as to perform the coordinated LTC operation between each transformer 2. Next, the operation of the automatic voltage / reactive power control device of this embodiment configured as described above will be described.

In FIG. 1, in each local control device 12, the LTCs from the LTC drive devices 13 of the plurality of transformers 2 are connected.
C drive information, power system voltage, current, active power,
Each piece of reactive power information is collected and transmitted to the overall control device 11.

Further, the equipment control device 11 is preliminarily inputted with the respective device characteristic data, and the L of the plurality of transformers 2 is set.
Based on the information of the voltage, current, active power, reactive power of the control target system necessary for the overall control of the TC, the LTC drive information, and the information of the central power supply command center, coordination between the transformers 2 can be achieved. L of each transformer 2 to perform the LTC operation
TC is centrally controlled. As a result, the LT of each transformer 2
Coordinated voltage reactive power control that does not cause divergence or hunting between Cs is performed.

On the other hand, as the coordinated control between the LTCs of the transformers 2, it is LTC how the operation of one LTC affects the control target voltage and the reactive power of the other transformers 2.
If the calculation is performed before the operation and diverging or hunting occurs, the LTC operation is locked. In case of divergence or hunting phenomenon, it is
Judging from the drive information of C, each LTC is locked.

Furthermore, since the local control device 12 has a function of manually operating the LTC when the integrated control device 11 is excluded, sufficient control can be performed manually when the integrated control device 11 is excluded.

As described above, in the automatic voltage / reactive power control device of this embodiment, the voltage and current information of the power system which is the control target of the automatic voltage reactive power is PT3, respectively.
The power and reactive power transducers which are extracted by PT4 and stored internally based on the voltage and current information obtain active power and reactive power information, and these pieces of information are sent to the integrated control device 11 together with the LTC drive information from the LTC drive device 13. A local control device 12 having a function of outputting and a function of manually operating the LTC when the integrated control device 11 is excluded is provided for each transformer 2, and is shared by a plurality of transformers 2 in the vicinity in the power system. One integrated control device 11 is provided, and the LTs in which the transformers 2 are coordinated by the integrated control device 11 are provided.
Since the LTC of each transformer 2 is centrally controlled so as to perform the C operation, it is possible to perform stable voltage / reactive power control without divergence or hunting between the LTCs of each transformer 2. Become.

Further, since the control can be performed only by providing one integrated control device 11 commonly to the plurality of transformers 2, the local control device 12 can have a simple structure.
It is possible to obtain an automatic voltage / reactive power control device which is extremely advantageous from the conventional one.

In the above embodiment, the case where one integrated control device is commonly provided for transformers for a plurality of generators has been described, but not only the transformers for a plurality of generators,
Even if it is used in combination with a transformer for a substation,
It is obvious that the same effect as described above can be obtained.

[0030]

As described above, according to the present invention, the system voltage and reactive power of the power system in which a plurality of generators are respectively connected via transformers are used to switch taps provided in each transformer. In the automatic voltage / reactive power control device that controls within the target range by switching the taps of the switch, the drive information of the tap switch and the voltage, current of the power system,
It collects and outputs each information of active power and reactive power, and has a function to manually operate the tap changer when the integrated control device is excluded, and a local control device provided for each transformer and a generator and a transformer. Coordinated taps between transformers based on device characteristic data, central power supply command station information, tap changer drive information from each local control device, voltage, current, active power, and reactive power information Since it is configured with the integrated control device that is commonly provided to each transformer that integrally controls each transformer tap changer to perform the switch operation, it is possible to prevent divergence or hunting phenomenon between the voltage / reactive power control devices. Extremely reliable automatic voltage that can perform stable voltage reactive power control that does not occur
A reactive power control device can be provided.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an automatic voltage / reactive power control device according to the present invention.

FIG. 2 is a block diagram showing a configuration example of a conventional automatic voltage / reactive power control device.

FIG. 3 is a diagram for explaining a control operation of voltage / reactive power control in the voltage / reactive power control unit of FIG.

FIG. 4 is a diagram for explaining a dead zone setting range in a dead zone setting unit in FIG.

FIG. 5 is a diagram for explaining a divergence phenomenon in conventional automatic voltage reactive power control.

FIG. 6 is a diagram for explaining a divergence phenomenon in conventional automatic voltage reactive power control.

[Explanation of symbols]

1 ... Generator, 2 ... Transformer, 3 ... PT, 4 ... CT, 11 ...
Integrated control device, 12 ... Local control device, 13 ... LTC
Drive.

Continuation of front page (51) Int.Cl. ⁵ Identification number Reference number within the agency FI Technical display location H02J 3/50 A 7319-5G (72) Inventor Takahiro Toyosumi 1-1-1 Shibaura, Minato-ku, Tokyo In Toshiba Head Office (72) Inventor Toshio Kaneko 1-1-1, Shibaura, Minato-ku, Tokyo Inside Toshiba Head Office

Claims (1)

[Claims] 1. A target range of system voltage and reactive power of a power system in which a plurality of generators are respectively connected via transformers by switching taps of a tap changer provided in each transformer. In the automatic voltage / reactive power control device to control in, while collecting and outputting the driving information of the tap changer, and the voltage, current, active power, and reactive power information of the power system, when the integrated control device is excluded. From the local control device provided for each of the transformers having a function of manually operating the tap changer, device characteristic data of the generator and the transformer, central power supply command station information, and the local control devices. Based on each tap changer drive information, voltage, current, active power, and reactive power information, the tap changer operation is coordinated between the transformers. Each transformer automatic voltage and reactive power control device comprising a general control device provided in common to the respective transformer for overall control of the tap changer, in that it comprises an.