JPS58144923A - Controlling method of reactive power - Google Patents

Abstract

PURPOSE:To enable control of reactive power for a highly accurate system with the minimum necessary equipment, by controlling the large-capacity capacitor group and the small-capacity capacitor group with different reactive power controllers, respectively. CONSTITUTION:A reactive power controller 7 works when the delayed reactive power increases after the application is through for all switches 8, 9 and 10 of a capacity having small unit capacity. Then a capacitor 17 of large unit capacity is connected to a bus 4 with application of a capacity switch 11. In this case, if the capacity of the capacitor 17 is larger than the increment of the delayed reactive power of a system, the system has the advanced reactive power. Thus a reactive power controller 6 works. As a result, one of capacitors 14, 15 and 16 of small unit capacity which is equivalent to the advanced reactive power is cut off from the bus 4 when one of the switches 8, 9 and 10 is cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a reactive power adjustment method that enables highly accurate reactive power control in power receiving and transforming systems of general power consumers such as factories.

[Technical background of the invention]

At power consumers, load equipment generally involves delayed reactive power, and this delayed reactive power causes a decrease in the power factor of the grid,
It is necessary to compensate for delayed reactive power because it causes increased power loss, voltage instability, and increased power charges. Figures 1 and 2 show conventional reactive power adjustment to compensate for delayed reactive power. 4 shows an example of the device. In the figure, 1 is a power receiving point, 2 is a voltage transformer, 3 is a voltage transformer, 4 is a bus bar, 5 is a load equipment, I is a reactive power regulator,
8,9゜10 is capacitor switch% 14.15.16
is a capacitor, and 20 is a DC power supply, which is configured as shown in the figure.
Power is supplied to load equipment 5 through 4. Good, mother I! A power capacitor 14 #151711 is connected to the power capacitor 4 through capacitor switches 8 and 9°10. The reactive power regulator 6 receives the system current and voltage signals detected by the calculator current transformer 2 and the instrument transformer 3, calculates reactive power, and compares this with a preset nine reactive power. When it is necessary to compensate for delayed reactive power, one contact of the capacitor switch control relay 61', 62.6:I inside the reactive power regulator 6 is turned on depending on the magnitude of the delayed reactive power, and the capacitor is switched on and off. Closing relay Cx of device 8゜9.10
Operate the capacitor switch Jl t 9 e J
O is turned on, and capacitors 14, 15, and 16 are connected to bus 4. Also, when it is necessary to compensate for advanced reactive force, internal capacitor switch control relay g 1 e 6 J of reactive power regulator G - By turning on the b image point of 6J, the capacitor switch 8*9. Lo is activated and the interrupt relay function is activated to connect the capacitor switch s*s, l.

t and then interrupt the power capacitor 14e15exe. Note that in FIGS. 1 and 2, a case is described in which there are three capacitor control points as a conventional reactive power adjustment device.
The number of capacitor control points varies depending on the type of equipment in the reactive power adjustment device.

[Problems with background technology]

By the way, as the installed capacity of power equipment increases, the amount of reactive power also increases, so when attempting to control it with one reactive power regulator as in the conventional method described above, the capacitance of the unit capacitor is reduced to a smaller tt. If you increase the number of capacitors while keeping them unchanged, capacitors, capacitor switches,
A large number of reactive power regulator capacitor control points are required.

9. Conversely, if you increase the capacity of the unit capacitor and leave the number of capacitors unchanged, the accuracy of reactive power adjustment will deteriorate.

If a capacitor with a large unit capacitance and a capacitor with a small unit capacitance are used together, a sequence circuit having multiple mother turns must be provided externally, resulting in cost savings.

As described above, control using one reactive power regulator has many difficulties.

[Purpose of the invention]

The invention was made in view of the above-mentioned circumstances, and its purpose is to make it possible to perform highly accurate reactive power adjustment with the minimum necessary equipment and to facilitate effective use of equipment during equipment expansion. An object of the present invention is to provide a reactive power adjustment method.

[Summary of the invention]

In order to achieve the above object, the present invention detects the difference between the reactive power in a power facility equipped with a plurality of capacitors and the reactive power scheduled to be compressed, and controls the opening and closing of the capacitor based on this. In a device in which the overall reactive power is adjusted by a reactive regulator, the capacitors are combined into a first capacitor group consisting of capacitors with small unit capacitance and a second capacitor group consisting of capacitors with large unit capacitance. a first control unit configured to separately control the reactive power adjuster and the first and second resistor groups;
, and a second reactive power regulator, and under normal conditions, the first
The first capacitor group is controlled by the reactive power regulator, and the second capacitor group is controlled by the second reactive power regulator only when all the first capacitor groups are in the closed or tripped state. [Embodiment of the invention] Hereinafter, an embodiment of the present invention shown in the drawings will be described.
FIG. 3 shows an example of a system configuration equipped with a reactive power adjustment device according to the present invention, and the same parts as in FIG. The figure shows a system equipped with one more reactive power regulator 1, capacitor switches 11°, 12.13, and capacitors 1F, 1.8', and 19 in addition to the one shown in FIG. Here, the reactive power regulator 7 has the same function as the reactive power regulator 6, and based on the outputs from the instrument current transformer 1 and the instrument transformer 3, the capacitor switch
12 This is a book that controls the opening and closing of the capacitor 14°15mlg connected to the bus bar 4 through e13. The capacitors 14, 15, 16 (first capacitor group) have the same capacity, the capacitors 17゜ismxs (second capacitor group) have the same capacity, and the capacitor 14
．． The capacity of 15.16 is the power capacitor 1 / + 18
119, and the capacitor 14.15-
Figure 4 shows a specific example of the internal connection configuration of the reactive power regulator 6. - capacitor switch control relay 61゜gz, 63 am point inside reactive power regulator 6,
When the b contact is turned on, the content 1i switch 11. g,
io's closing relay CXs and interrupting relay TX i are driven, capacitor switch 8, side, 100 closing relay CX, L
If the connection is lost to activate the interrupt relay TX,
Input status contact 1t1 of capacitor switch 8*9elO,
Only when a series circuit w1 or b contact of the ao advantage of 91°101 is formed, the capacitor switch control relay 11°rx, vs a contact and 111 contact inside the reactive power regulator 7 are turned on. , capacitor switch 11e
12. Connect the closing relays CX, L, and interruption relay TX of 1B to operate.Here, the reactive power adjustment 1jz6 is set to issue a control command when the reactive power is equal to the capacity of the capacitor 14,
The reactive power regulator 1 is set to issue a control command when the reactive power difference is larger than the capacitor 14 and smaller than the capacitor 11.Next, a reactive power regulating method according to the present invention based on this configuration will be described. Reactive energy regulator 6
．． 1 receives system current and voltage signals from the instrument current transformer 2 and instrument transformer 3, calculates reactive power, and sends a control command based on the difference from the preset 9 reactive power.Reactive power In the case of regulator 6, when the difference in reactive power is equal to the capacitor 14ellj*ILIK with the same capacity, the lagging reactive power M9 drives the capacitor switch control relay 61.62.6jl to compensate for the leading reactive power. In other words, in the case of delayed reactive power compensation, the capacitor switch 1t,
9. Jo's closing relay CX is driven to close the capacitor switches 8, 9, and 10, and in the case of compensation for advanced reactive power, the interruption relay TX is driven to cut off the capacitor switches 8, 9, and 10. ), capacitor 1
4゜15*16 is turned on and off from bus 4 to compensate for reactive power.

On the other hand, in the case of reactive power H adjustment *7, capacitor switch 8.
9. ．． 10 is fully closed or suspended, that is, capacitor switch (4) important letter 11 grade J1
1.91e101's A contact or tibm point is satisfied, and when the actual reactive power difference is smaller than the capacitors 171, 18, and 19 of the same capacity and larger than the power capacitor 14), the above reactive power Similar to the regulator 6, capacitor switch control relays 71, 72 .
73 and capacitor 11 * I Jl #
Compensate for reactive power by turning J9 on or off from bus 4.Next, the overall operation will be described. Now, when the delayed reactive power generated by the load equipment 6 increases, the reactive power regulator 6 operates as the delayed reactive power increases, and the capacitor 14elliazr; with a small unit capacity operates as a capacitor switch. 8+9*1o are input in order, and bus 4
This compensates for delayed reactive power.

Then, after all of the capacitor switches 8e9elO have been closed, when the reactive power increases with further delay, the reactive power regulator 1 is activated, and the capacitor 11 with a large unit capacity is connected to the bus bar 4 by closing the capacitor switches 11. At this time, if the capacitance of the capacitor 17 is large compared to the amount of increase in lagging reactive power in the grid, the grid will advance to reactive power, and the reactive power regulator II C will operate, reducing the capacitor 14 with a small unit capacity. .15.16, a portion commensurate with the advanced reactive power is disconnected from the bus 4 when any of the capacitor switches 8, 9, and 100 is interrupted to compensate for the reactive power. Furthermore, when the delayed reactive power increases, the reactive power regulator 6
operates and all capacitors 14, 15, and 16 are connected to bus 4 by closing capacitor switch 8e9e10.
is connected to compensate for delayed reactive power.

Note that when the delayed reactive power increases further, the reactive power regulator 7 operates again in the same manner as described above and the capacitor 18 is turned on, and if the capacitance of the capacitor 18 is larger than the amount of increase in delayed reactive power of the system, the system advances and the reactive power is increased. ), an amount of the capacitor 14.15916 corresponding to the leading reactive power is disconnected from the bus 4 to compensate for the leading reactive power. moreover,
As the delayed reactive power of the system increases, capacitor 14.1
5.16 are all connected to bus 4 to compensate for delayed reactive power in the grid.

Next, when the system's leading reactive power generated by the load equipment 5 decreases, the reactive power regulator 6 operates as the leading reactive power decreases, and the capacitor 14m15a16 with a small unit capacity opens and closes the capacitor. By sequentially shutting off the power converters 11, 9 and 10, the power is disconnected from the bus 4 and proceeds to compensate for the amount of reactive power. And capacitor switch 8゜9.1
0, and as the reactive power increases, the reactive power regulator 7 operates and disconnects the capacitor 17 with a large unit capacity from the bus 4 by interrupting the capacitor switch 11. At this time, if the capacitance of the capacitor 17 is large compared to the amount of increase in reactive power in the system, the system will be delayed in reactive power. Of this, the amount commensurate with the delayed reactive power is the capacitor switch l t
By turning on either of 9 e and 10, it is connected to the bus 4 to compensate for the delayed reactive power.If the reactive power further increases, the reactive power regulator 6 is activated and the power capacitors J4 and J5゜16 are connected. All 1 capacitor switches 8 and 9.10 are cut off (bus line 4) and proceed to compensate for reactive power.In addition, as the reactive power increases further, reactive power adjustment is performed in the same way as above. When the capacitor 7 is activated again and the capacitor 18 is interrupted, and the capacitance of the capacitor 18 is larger than the amount of increase in the reactive power of the system, the system becomes a lagging reactive power, and the capacitors 14, 15, and 16 correspond to the lagging reactive power. is connected to the bus 4 to compensate for the lagging reactive power.Next, when the reactive power of the system further increases, all of the capacitors x4.15゜16 are disconnected from the bus 4 and the system becomes reactive Compensate power. Furthermore, when the leading reactive power of the system increases, the capacitor 19 is disconnected from the bus bar 4, and when the capacitance of the capacitor 19 is larger than the leading reactive power of the system, the system becomes a lagging reactive power, and the capacitors J'4', L, Of S and Jc, an amount commensurate with the delayed reactive power is connected to the bus 4 to compensate for the delayed reactive power. Furthermore, as the system's leading reactive power increases, all power capacitors 14, 15, 16 are disconnected from the bus 4 to compensate for the system's leading reactive power.

In this way, by creating a large capacity capacitor group and a small capacity capacitor group using separate reactive power regulators, it is possible to control the reactive power of the system with high accuracy without unnecessary input or interruption of capacitors. Become.

In this way, the difference between the reactive power in a power facility equipped with multiple capacitors and the preset reactive power is detected, and based on this, the opening and closing of the capacitors is controlled and the reactive power of the entire facility is adjusted. In a device in which the force is adjusted by a device, the above capacitors are divided into a first capacitor group consisting of capacitors 14 to 16 with small unit capacitances and a second capacitor group consisting of capacitors 17 to 19 with large unit capacitances. In addition, the reactive power regulator is configured to have first and second reactive power increases of 6 s F for controlling the first and second capacitor groups respectively, and in normal times, the reactive power regulator is The reactive power regulator C) controls the first capacitor group, and the second reactive power regulator C controls the second capacitor group only when all the capacitor groups Kn are in the closed or tripped state. There are 9 things you can do to control the group.

Therefore, in the conventional reactive power adjustment method, when increasing the total capacitance of the equipment's capacitors, increasing the unit capacitance of the capacitor impairs the accuracy of reactive power control, and in order to increase the precision, the capacitor capacitance is reduced. However, increasing the number of capacitors led to an increase in cost, but this reactive power adjustment method allows much more accurate reactive power control than conventional methods with the minimum amount of equipment required, and also reduces the cost of equipment. During reinforcement, it becomes possible to easily utilize equipment effectively.

In addition, above, we have described the case where the number of manual control points for the capacitor switch of each reactive power regulator is 3 points, but if the number of important points of the reactive power regulator is large, more accurate reactive power adjustment is possible. Become.

In addition, without being limited to the contact circuit of the above embodiment, a reactive power regulator 6 for fine adjustment is also available, aiming at highly accurate reactive power control.
Priority is given to the control of the coarse adjustment reactive power regulator 1,
And as a method, use reactive power for fine adjustment all! The coarse adjustment reactive power regulator 1 can control the adjustment capacitor switches 17 to 19 only when all of the fine adjustment capacitor switches 14 to 16, which are controlled by the device 6, are in the ON or OFF state. [Effects of the Invention] As explained above, according to the present invention, it is possible to achieve high accuracy with the minimum necessary equipment and to easily make effective use of equipment during equipment expansion. We can provide an extremely reliable reactive power adjustment method that can perform reactive power adjustment.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are diagrams showing a conventional reactive power adjustment device, and FIG. a13 and FIG. 4 are configuration diagrams showing an embodiment of the present invention. 1... Power receiving point, 2-- Instrument current transformer, 3... Instrument transformer-4... Bus bar, S-... Load equipment, 6.7...
・Reactive power regulator, 8, 9*10, 11, 12.13・
・・Capacitor switch, i 4 # 15 p 16
p 17 e1B91G-・con, capacitor, 2o...
DC power supply, 61゜62, σJ...Capacitor switch control relay of reactive power regulator 6, 7J, 7j, 7j-...
Reactive power 1111" Capacitor switch control of device-1"
-1ll. 91.101...Capacitor switch 8*9@100 input WIA contact. Applicant's agent Patent attorney Takehiko Suzue 13 Figure 1 i Figure 2 Figure 3-1:

Claims (1)

[Claims] Detects the difference between the reactive power in a power facility equipped with multiple capacitors and a preset reactive power, controls the opening and closing of the capacitors based on this, and adjusts the reactive power of the entire facility using a reactive power regulator. wherein the capacitor is configured to include the capacitor group, and the reactive power adjustment unit 11 is configured by the III, the second capacitor group is controlled separately, 1I11, and the second reactive power unit 111, A reactive power adjustment method in which the capacitor group of the path 1 is controlled by the first reactive power regulator during normal times, and the capacitor group of the second capacitor group is controlled.