JPS5961433A - Voltage reactive power control system - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] Does this invention apply to both voltage and reactive power? The present invention relates to a voltage/reactive power control method that correlates and adjusts control within a predetermined range.

As the use of electric power increases and becomes more diverse and sophisticated, social demands for a stable supply of electric power are becoming increasingly strong.

On the other hand, due to the difficulty in locating power grid facilities to expand the scale of the power system, the power system is becoming more densely packed, causing problems in system operation.

In other words, remote power sources, unevenly distributed power transmission lines with static voltage, large capacity, long distances, underground cables, or heavy #1 flow? It is showing itself.

In order to operate such a system stably and economically, system type 8E
As a result, there is a desire to improve the functionality of voltage-reactive power control.

Is this the system reference voltage? To maintain this, Ichida and reactive power adjustment equipment are controlling sound and adjusting to grid type IEf'.

That is, more than 90% of the total number of on-load tap switching generators for W1+E adjustment are present, and the capacity of the stator converter and shunt reactor for reactive power adjustment has reached nearly 10 times the approved capacity of the transformer.

There are two methods for operating and controlling voltage and non-electric power that are widely used in systems equipped with such regulating equipment:

(a) Individual control method: Each electric station individually controls and adjusts the voltage and reactive power adjustment equipment of its own electric station, which maintains all the reference values given in advance.

(b) Combined control system B: Monitors main points of the system, centralizes online information such as voltage and power flow, and sends it from the computer at the central power dispatch center to the individual control equipment at each electrical station. Issues direct operation commands to control and adjust the sound of voltage and reactive power adjustment equipment.

The above two methods can be implemented in combination or alone, but
In this invention, the above items can be purchased individually or wholesale! We will study your method C and try to improve its characteristics.

Before going into detailed explanation of the present invention, an outline of the above-mentioned control system will be explained.

The configuration of both individual side types is shown in Figure 1.

In Figure 1, is 1 (0) the upper or lower power system? The transformer to be interconnected, (1) is the transmission line of the upper system that is connected to the transformer (0), (2) is the transmission line of the lower system,
(3) is also a power transmission line in the lower system, and has a slightly lower melting chamber pressure class and capacity than power transmission line (2). (4) is a transformer (O) VC
Attached on-load tap changer (hereinafter abbreviated as LTC)
is the winding to which t' is connected, and (b) is the control device (hereinafter abbreviated as LRA) of the switching mechanism. Similarly, in Figure 1, (5) is the shunt reactor with the lower system 8 (/C connection), the can υ is its switching breaker, and (611-j is a static capacitor (or synchronous harmonic machine)).・+611
is the opening/closing breaker. Reference numeral (7) denotes an electronic/null force control device (hereinafter abbreviated as vQC), which issues opening/closing or adjustment commands to the control device 0υ and the circuit breaker f51+16υ. [+1121] C11l is the power transmission line (1) (21+31 electricity 1? Transforming PT (DJ/
02' (a) and 0 are CTs that transform the currents of the power transmission lines +11421 and +3), respectively.

The operation of the conventional method with the above configuration is to maintain the voltage at the bus line C20) voltage VkeVQC (71, and the voltage and current kVQC+7 of the father system). Then, the changes ΔV and ΔQy are detected, and it is determined by IVQc whether ΔV and ΔQ satisfy the predetermined relationship f′, and L RA (41), S 11 R1511, Se
This is a command to raise and lower t6u yc, or to open or close it.

The measurement and judgment of these ΔV-ΔQ is normally carried out by comparing it with the standard established by Gakuen et al. Some adjustments are being made in stages.

However, due to changes in thread line conditions and load, △V-ΔQ
Is this because the key goal 8 is changeable? As a result of operating the system as a constant, in some cases, the blasphemy/nullity adjustment device may operate frequently or become impossible to adjust.

This is it'□ll! In order to avoid this, it is also practiced to operate the equipment after a certain period of time after the judgment result of △V - MQ, but this is to prevent malfunction due to temporary variable IVC. However, it is ineffective and ineffective against intermittent fluctuations and large-scale fluctuations in system conditions.

The present invention provides a system that completely eliminates these deficiencies.

Before going into the detailed description of the present invention, the basics of the present invention will first be explained.

FIG. 8 shows the system and its various quantities to be considered in the invention.

That is, the upper system (1) l'c! Power is supplied to the lower system +2) via J actance X+ Vc! J Actan 7X? Assume that the electric power modules V, , V, to which the loads are respectively connected through, are connected.

Transformer (0) Ic has tag change width and turns ratio n
Only △l] changes. Also, there is a harmonization facility attached to the Hen 1 King, and only the reactive power qkΔq is fathered.
,ru.

As a practical goal, the voltage that should be adjusted on the F511 side is the bus line (4
)), the city 1 king V, the simultaneous VC, and the passing reactive power Q. In general, (8-2) holds true.

Coconi ΔV8. ΔV, l't primary and secondary system flux actance X, +X, voltage fluctuation behind.

△V, ΔQ (1) The relational expression is derived from the above relational expression △Q−-
Nishireshih-e.

8, +Xs XI +X, -(8-
4) If Δq = O in the above equation, °, ΔQ, -1=・ΔV ・・
・(8-5) Also, if Δn=o in the above formula, then MuQ... 1 ・Δ■
...+8-6)1 Therefore, if the change is fL shown in Figure 7, in other words, on the ΔV-ΔQ plane, one side of the tap n of the LTC or the reactive power supply q of the phase adjustment equipment is fully connected. Change pregnancy・each△n・
Δq? ! If l-occurs, the change in V and Q at that time 1
/c, there is the above-mentioned relationship.

That is, ΔQ−ΔVO) represents the value of X (r) of the slope kick actance of linear change (X2).

In other words, the change in △Q-Δ■ causes the actance XI
r You can know XQke.

In other words, harmonic equipment for a very short period of time (about 10 seconds or less)? Operation and change? Changes in detection, system voltage, and reactance can be ignored, so actance XI +
X2 can be identified. This is because mn.△q is an adjustment example number for printing regulations from VQC at our site, and this value can be easily determined.

That is, Δn, Δq'r are catalytically exfoliated and ΔV,
Eri reactance Xll can be easily calculated by measuring ΔQ.
X2 is calculated and you can get pregnant.

Next, use this reactance xt + x4 and get a little! ∆V until the time when the equipment in the facility is not controlled.

(1) Monitor changes.

When the system is operated, Haru V becomes slightly larger, so f'L
? Detection of V and Q's hardness is measured by 09Δq==QΔV=−−V+□ΔV ・・・(8-7)x,
+x! I"xt+xg' If we follow the above equation 6V and -ΔV9vc, we get M■t, M■.

I understand.

To keep △V and △Q within the target price from above 1', △n.

How much Δq should be manipulated can be calculated from the inverse animal-superior equation.

A detailed description of the invention will now be entered.

The configuration of an embodiment of the present invention is shown in FIG. 4 yc.

In FIG. 4, (0) to (6) αO to t611 are the same as in FIG.

Although the input and output of VQC (7) are similar to those shown in FIG. 1, the internal configuration consists of 1dvl)-4 and is essentially different from the conventional VC shown in FIG.

In addition, there is a potion ytba/harmonizing equipment + fil (al 151
116υ is a so-called static non-active power adjustment device with a built-in semiconductor device rather than a conventional device, which is a feature of the present invention? It is preferable to keep it alive.

VQ, Cf7) 1 individual element that forms 1
7ff ~ (731 is a converter for reactive power/voltage, H is a converter for system @[mo/electric 1 mo, (c) is a CPU that receives input from the converter, measures and processes it, and is marked with an input/output part, calculation/judgment part, and storage part. General PC
A commercially available microcomputer is sufficient for practical use, but this will be described later.

Qη is a signal insertion device (CD T, TT) used by the control center of this electrical station to install the upper @electrodeposition and exchange information.

It is an interface part with Sv, TM), etc., and is used in response to external requests.

Q■ (791 is the part that issues a control output to the L A A (40) and the reactive power adjustment device f5116+1511βυ in its own facility, and its command is given from the CPU controller.

CPU Kan's 111 works will be discussed later.

Next, regarding the K CPU i7d, as mentioned above, the output of the CPU's f-i conversion Mi+1 to ri0 is the output of the tuning fork. It has analog input multiplexer & U A/D converter, and digital pin) parallel input ports. Also CPUσ~V
In addition to the so-called central processing unit, c also includes memory (RA).
M, RQM). Furthermore, inter 7 earth FRS G Chemi ff9+ 7j on the output side of KCPH;
There is this interface part (2) l-ic
PUσ9) Level amplify the bit signal from the digital output port. L interrupter (5
1116110) Control t [rer road? It is something that energizes.

These hardware configurations are very common for digital type professionals, and their performance is generally available and there is no problem in practical use, so they are publicly known.
I don't dare to give any detailed explanations, especially regarding its speed, which is currently available on the market.The memory capacity is also about the same as that normally achieved as a one-chip processor.

Next, the operation of the embodiment of the present invention will be explained in detail. Figure 5 shows the flow of the process. When the trench is not controlled, the scratch memory is cleared at the start of this control operation, and the voltage and reactive power which are the reference values set separately (usually given as input from the interface 77 when given externally) are cleared. Set the reference setting value.

Next VC changes Δn (i.e. the tap of the tap changer) by an amount given in advance γ, and the voltage changes? give.

As a result, new voltage values and reactive power values will be obtained based on the relationships described in the principle section, but we will move on to measurement after confirming the relationship described in (2).

Although the measured value may not be large depending on the value of Δn, it is possible to measure Erivi'# with a highly accurate input circuit. This value? ! 17(aV)n, (△Q)n from this measured value ΔV, △Q -"△andL1...+8-9)
x9 (xV).

Calculate. Since this value is the system flux actance, it is the leakage reactance that arises from the capacity of the transformer, etc.
A range of reasonable values within a certain range can be set in advance.

Check whether this value is within an appropriate range given in advance.

Next, by the operation given in advance by 1, the harmonic equipment +51 +6
1'i operation to generate a change in reactive power Δq.

This yc also causes a sudden change in the voltage, but the change is about one order of magnitude lower than when operating Δn. Similarly, ΔV
, MuQ? It is difficult to measure the values of aV)q and (ΔQ)Q, but if the reactance Xs is small, the electron perturbation itself is small, so as long as VQCfz is applied, the reactance x1 must be larger than a certain level? It's good to have one.

Similarly, is the value obtained here also on the power supply side? Since it is the observed systematic glue actance, it has an appropriate size @r, and its validity can be checked in the same way as described above.

Furthermore, looking at the change in ΔV, △QO') obtained by the above two operations, it is 3°v)"" X4 +y,, - °°33
°11)... (8-12) (ΔQ,)==,-,,,,there is a relation of 6°, so is there a relation? It is possible to check using rTr.

Using Xl + Xq obtained from the above one process, Δn
, △q change, sensitivity coefficient tt +2 While calculating, are there no sudden changes in △V and ΔQ? Confirm/identify? 8-1) (3-2)
The coefficient of each term in the equation is determined.

In an actual system, there are fluctuations in external system voltages such as ΔvI and ΔVg, but reliable results can be obtained by taking seven appropriate samples and performing measurements multiple times over short periods of time.

In that case, Δn and Δq are directly known, and Δv8. Δv,.

You can also consider ΔV, ΔQ x, +x, and VC, find several sets of X1+X2 values, and take the average.

Above, Eri△n・Δq, Δ■8. The sensitivity coefficient for ΔV is determined.

One-man identification routine? The process ends and moves to the normal measurement control routine.

This routine starts on time, but as with the identification, ΔV
, the measurement of muQ is calculated using the procedure described in m1
Voltage fluctuation of the back power supply from Δ■1. MuV.

seek.

At this time, there is no sudden change in V, and n means no system operation, so after confirming with Bluenan that there is a sudden change in ■ (8-1
, (8-4) is solved to obtain Δn.

Find Δq.

Here, we use L T C (
4) and output to harmonization equipment 5.6.

In this case, all equipment operations are being performed, so there is aV in the home.

ΔQ strange! A sudden change in l/cv should have occurred before R1m occurs. After confirming this, I updated it with a new rori・△Q
? measure.

0) △V, △Qij above formula (8, 8), (8-4
)', so it should be equal and opposite in sign to Taikihata.

If this value has not changed, it means that it has returned to the appropriate standard price, so it can be said that the voltage increase, η adjustment, and reactive power adjustment were successful.

Also, if this one city is significantly different from the initial planned △V and △Q values, V as shown in equations 1-j (8-1) and (3-2).
Since changes have occurred in the C upper and lower systems, new Δn is again given to new Δ■, ΔV.

It takes a lot of effort to find and operate Δq meetings.

That is, if a certain amount of time is allowed for checking the ratios of ΔV and ΔQ performed in (a), it is not necessary to perform this equipment operation frequently.

With this, the normal measurement and control routine started at regular time intervals is completed.

While executing this routine repeatedly, the value of ・X1 + In the event of a movement such as output, the control logic is such that the process moves to the above-mentioned identification routine and identifies XI xs at the same time.

As mentioned above, the amount of equipment operation required for VR and engineering of the present invention is based on the system identification results. Because the operation is performed after direct swarming, it is highly accurate and responds quickly to changes in system status.・S・1+XgI
You can add t.

Even if the transmission equipment is rarely used, the individual open side 1
Since it is possible to perform the optimum operation at the same time, controllability is significantly improved compared to the conventional method, and unnecessary operations of equipment can be avoided.

[Brief explanation of the drawing]

Fig. 1 is a system connection diagram showing general individual wholesale 1 @ system γ, Fig. 2 is a system connection diagram for explaining the details of this invention, and Fig. 8 is a system connection diagram for explaining the details of this invention, △V and △Q. FIG. 4 is a system connection diagram of an embodiment of the present invention, and FIG. 5 is a flowchart for explaining the entire operation sequence of the fourth I-1 (J). Figure VC5? (0) is the transformer, (1) vi upper system transmission line, +2) (3) lower system transmission line, (5
19′i shunt reactor, (6) is the capacitor, Oυ is the control device for the on-load tag switch, fall tell is the LO disconnector, (7) (d V Q C, Qllila is the reactive power/voltage converter, 4 is the grid/voltage exchanger,
4. Appropriate the current position of the on-load tap changer.ME
l: E K f converter, (71QCPU, (
7η(y21 +9) is an interface section. The same reference numerals in the two figures indicate the same or corresponding parts. Agent Makoto Kuzuno - Ward faction Figure 2 Figure 3 Figure 1 (0) Figure 2 (b)

Claims (1)

[Claims] In a system that controls and adjusts both the WE and reactive power of the grid within a predetermined range, the voltage and reactive power are controlled near the equipment that adjusts the voltage and reactive power, and the power supply and reactive power are controlled on the load side. Is it possible to identify all impedances and immediately respond to changes in the source and load, correlate the voltage and reactive power, and control/adjust them within a predetermined range? Characteristic electric power/reactive power charge system.