JP2597556B2 - Power system information data output device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial application field) The present invention relates to a method of determining the amount of electricity during or after an accident or recovering from an accident when an accident such as a short circuit or ground fault occurs in an electric power system. The present invention relates to an improvement of a device for outputting a function value as digital data.

(Prior Art) Since the digital operation type protective relay device using a computer became practical, the voltage and
2. Description of the Related Art Digital data such as a magnitude of a current, a ranging impedance of a distance relay and a reactance thereof are obtained as an output. However, these data do not make it possible to clarify the phase relationship between the quantities of electricity at multiple electrical stations.

If the power system accident is a simple accident that is limited to one point and the accident situation does not change, and if the accident is interrupted by the correct operation of the protective relay, the phase of multiple electric stations Even if the relationship is not clear, there is generally no problem in analyzing the phenomena at the time of the accident or examining the response of the device.

(Problems to be Solved by the Invention) However, if the accident shows a complicated aspect, for example, (i) an accident occurs at multiple points simultaneously (multiple accidents), (ii) a disconnection and a ground fault accident occur simultaneously (Iii) the number of phases of an accident changes during an accident (evolving accident), and the voltage / current phenomena at the time of the accident in the process of successively shutting down these accidents. When analyzing the response of a protection relay or a protective relay, it is extremely convenient to clarify the phase relationship between a plurality of electrical stations during an accident.

Also, in the case of fault location using the voltage and current of the power system, errors can often be reduced if the phase relationship between the quantities of electricity at a plurality of substations during the accident is clarified. This will be described with reference to the drawings. FIG. 8 is a single-line diagram for explaining the phenomenon at the time of a two-terminal transmission line accident, where L is the transmission line, A and B are the respective terminals, and F is the fault point. Respectively flowing current _A and _B from the terminal A and B current flows _F in the fault point F. The accident point has an accident point resistance _F. Km of transmission line
The impedance per unit is _L , and if the distance between the accident point F and the terminal A is χkm, the impedance between AF will be χ
_L. The voltage at terminal A is represented by _A.

Under the conditions shown, the voltage _A is expressed by the following equation. _{A = A x L + F B} ... (1) In this case the most accurate as it can range finding is to be due to the following principles.

However phi _V is _{angle A} is advanced than _F, phi _I is _{A L}
Is the angle of advance from _F.

FIG. 9 is a vector diagram for explaining this. Current _F
And _A show a state where there is a slight phase difference. Voltage _A is represented by two terms in equation (1), _F is a pure resistance and _L
Since a large impedance of inductance, _{F F} is _F and in phase, _{A L} is 90 ° weak phase advances from _A. (2) each molecule V _A sin [phi _V and denominator _{I A} Z _{L sinφ} I of _formula, represented by the projection for linear Ol of _A and _{A L,} for projection of _A is equal to the projection of _{x A L} (2) The distance x can be accurately measured by the formula.

Features of this principle is the influence of the voltage drop _{F F} at the fault point resistance is erased, it lies in locating precision is possible, knowing the phase of the magnitude and current _A current _B to know current _F There is a need.

FIG. 10 is a diagram for explaining the problem of fault location in a multi-terminal transmission line, and the same parts as in FIG. 8 are indicated by the same symbols. In the figure, C
Is the third terminal of the transmission line L, J is the branch point and the current is
_C flows. The impedance between terminal A and junction J
Indicated by _AJ , the distance between junction J and accident point F is xkm, km
The impedance per hit is indicated by _L.

In this case, to avoid the influence of errors due to voltage drop _{F F} accident point resistor to know the fault point current _F as described above is as abandoning, there is still another problem. In other words, when the fault point F is in the section CJ and the power supply at the terminal C is weak, and when the current _C hardly flows, the distance measurement at the terminal C becomes impossible. In this case, the distance must be measured by a terminal having a large power source behind the terminal and through which a large current flows, for example, terminal A.

In this case, the voltage _A - _{A AJ} indicating the voltage at the branch point J
The _{A - A AJ = (A +} B) x L + F F ...
(3) becomes the same as in the case of the equation (2). However, phi _V 'is _A - _{A AJ} angle proceeding from _F phi _I' is _{(A + B) L} is the current _F assuming _A + _B or _A and in phase where an angle proceeding from _F, fault point current even for orientation without the use of _F, noted it is necessary to calculate the current _a + _B, the current _a
It is necessary to know the phase relationship between _B and _B.

Further, after the recovery from the accident, fluctuations occur in the electric power and the voltage phase difference angle between different points, and in a severe case, a step-out occurs. It is extremely important for the stable operation of the power system to clarify the development. Conventionally, however, analysis has been performed using a computer.
It is only a record of the magnitude of the current. For this reason,
The difference between the analysis and the actual one has not been sufficiently elucidated, and it is necessary to clarify the phase relationship between the voltages of multiple electric stations after the recovery from the accident in order to sufficiently elucidate the difference.

As described above, obtaining data that clarifies the phase relationship between the air amounts at a plurality of electric stations during or after an accident brings various conveniences. However, there has been no suitable means for obtaining this data. Of course, if the instantaneous value waveform of voltage or current is transmitted to a distant place by means such as PCM or frequency modulation, it is possible to know the phase relationship,
This requires a large amount of high-speed information transmission.

The present invention has been made in view of the above, and an object of the present invention is to provide a means for outputting information data capable of easily clarifying a phase relationship between a plurality of electrical stations at work or after an accident with a small amount of information. .

[Configuration of the invention]

(Means for Solving the Problems) The present invention uses a pre-fault voltage (normally, relative earth voltage, inter-phase voltage or positive-sequence voltage) of a power system as a reference voltage _P. A calculation is performed using the sampled value of the subsequent electric quantity (voltage or current for each phase or symmetry), and a plurality of functions that can specify the phase angle θ or the angle of θ with respect to the reference voltage _P of the electric quantity. The value is output as information data.

Such information data and each size of _P E and V _P (e.g. effective value) when the angle is θ example V _P Ecosshita and V _P Esinshita proceeding from _P ... (5) _Ecosθ and Esinθ ... (6) sinθ (or cosθ) and tanθ (or cotθ)…
(7) θ ... (8) Output in various forms. Further, the present invention is not limited to the combination of the shapes of the respective formulas. For example, V _P Ecosθ and V _P Ecosθ and tanθ, etc., the angle of θ is 0 ° ~ 360 ° or-
Various combinations are possible as long as they can be specified in the range of 180 ° to + 180 °.

(Operation) If the phase relationship between the value of each electric quantity during the accident or after the accident and the pre-accident voltage (reference voltage) _P is clarified by such means, each reference voltage at a plurality of electric stations before the accident is obtained.
The phase relationship between _P should be calculated from these values and the constants of the system components, by obtaining information on the system operation status such as voltage, power reactive power, and switching status of the switchgear in the always-on state before the accident. Therefore, it is possible to clarify the phase relationship between the quantities of electricity during or after an accident at a plurality of substations.

(Embodiment) FIG. 1 shows the configuration of an embodiment of the present invention. Power system
a, b, c of each phase voltage _{a, b} and _c and the current _{a, b} and _c are added to each input transducer 1-1 to 1-6,
It is converted into voltages e _{1 to} e ₆ proportional to each input. The input converter is provided with a band-pass filter, and is obtained as an output of the input converter from which the high frequency component and the DC component of the input electric quantity have been removed.

The voltages e _{1 to} e ₆ are respectively set to the sample hold circuits 2-1 to 2-
6, and all voltages are sampled simultaneously, and that voltage is held until just before the next sample is taken. The sampling period is selected to be an integral multiple of the power system frequency, for example, 8, 12, 16, 24 or the like. The voltage of the sample and hold circuits 2-1 to 2-6 applied to the held voltage multiplexer 3 is sequentially applied to an analog-to-digital converter (AD converter) 4 to be converted into digital data. This digital data is stored in a random access memory (RAM) 6 for a predetermined period.

Using the stored data, a microcomputer (MPU) 5 calculates information data according to a procedure stored in a read-only memory (ROM) 7 and outputs required information data to an output device 8. As the output form, various known means such as a display by a counting indicator, printing by a typewriter, or a pulse code modulation (PCM) signal for remote transmission are used.

The processing flow of one embodiment of the present invention will be described with reference to FIG. When started in step S1 it is commanded captures digital data corresponding to the sample value of the voltage e ₁ to e ₆ in step S2 (hereinafter referred to as sample data). The acquired sample data is collectively represented by d _0-1 . Subsequently, in step S3, it is detected whether or not a scheduled time has elapsed after the start, and if it has elapsed, an accident is detected in step S4. Step S5 when no accident detection is performed and before the scheduled time elapses
The shift performs rewriting of the reference voltage data by later of (11), after performing the creation of reference data v ₁ further step S6, the procedure proceeds to step S11.

If an accident is detected in step S4,
In S7, it is determined whether or not there is an output command in a procedure described later. If there is no output command, the process moves to step S10. If there is an output command, the information data is calculated in step S8, and the calculated information data is output in step S9.
Move to S10. In step S10, the reference voltage data is rewritten according to equation (12) described later, and the process proceeds to step S11. In step S11, after rewriting the sample data by the expression (10) described later, the process proceeds to step S2, and the above-described processing is repeated.

Next, the processing in each step will be described. Although each step process differs depending on the sample frequency, a case where the sample frequency is 12 times the system frequency, that is, a case where 12 samples are performed in one cycle of the system frequency will be described as an example.
Hereinafter, this sample period is used unless otherwise specified.

The rewriting of the sample data in step S11 is based on the following equation.

That is, the latest sample value d _0-1 is stored as d _0-2 , and the sample value stored as d _0-2 is stored as d _0-3 . Similarly, the process is shifted to the forward direction, and d _0-11 is stored as d _0-12 . sample data d _0-12 is transferred to d _1-1, data d _1-1 to d _1-11 is stored as d _1-2 to d _1-12 are progressive, data d _1-12 Is rejected.

Reference voltage data v ₁ step S6 is created. This data v ₁ is created from the sample data d _1-12 before being replaced at step S11. That is, when one-phase voltage, for example, voltage _a is used as the reference voltage, data d
_A- phase voltage sample data from _1-12
v ₁ is the difference between the two phases, for example, the difference between the voltages _a and _b .
_a - data calculated the difference between the voltage data of the sample data d _1-12 is data v ₁ When using _b.

The process of rewriting the reference voltage data in step S5 is based on the following equation.

That data v ₁ to v ₁₁ is transferred to v ₂ to v ₁₂ in forward,
v ₁₂ is rejected.

The process of rewriting the reference voltage data in step S10 is based on the following equation.

v ₁ → v ₂ , v ₂ → v ₃ ,... v ₁₁ → v ₁₂ , v ₁₂ → v ₁ ... (12) In this processing, the data v ₁₂ is returned to v ₁ without being rejected.

Thus, the sample data d _{0-1 to} d _0-12 and d _{1-1 to} d _1-12
Indicates one cycle of the system frequency, d _0-1 and d _1-1 , d
_0-2 and d _1-2 and d _0-12 and d _1-12 mean data of one cycle difference. In this sample data, the oldest data d _1-12 is rejected and the latest data d
_0-1 is replenished and updated every sample. Similarly, the reference voltage data v _{1 to} v ₁₂ are data for one cycle. If no accident detection is performed, it is updated every sample, and v _{1 to} v ₁₂ are two cycles before by d _0-1 to d _0-12 , d
_{1-1 to} d _1-12 are data one cycle before. When fault detection is performed updating of the reference voltage data v ₁ to v ₁₂ is stopped, fault detection previous data is held. At this time, the data v _{1 to} v ₁₂ are data that are integer cycles before (but two or more cycles) ahead of the data d _{0-1 to} d _0-12 .

Step S3 is an initialization process. That is, it takes three cycles for the sample data d _{0-1 to} d _1-12 and the reference voltage data v _{1 to} v ₁₂ to be completed. Therefore, during this time, only the data accumulation is performed, and the accident detection process of step S4 is performed only after the scheduled time elapses, that is, when the data accumulation is completed.

The accident detection processing in step S4 is similar to that of a known digital operation type relay. For this detection, for example, a distance relay, an undervoltage relay, a ground fault overvoltage relay (an overvoltage relay responding to a zero-phase voltage), or the like is appropriately used according to a system to which an operation is applied. Examples of these calculation methods are pages 112-114 of the Institute of Electrical Engineers of Japan Lecture Protection Relay Engineering (hereinafter referred to as Reference Document 1) and IEEE Tutorial Course C
omputer Relaying (79EHO148 ・ 7 ・ PWR) (Reference 2)
) On pages 16 to 23, and the description is omitted for simplicity.

The output command in step S7 is for limiting the number of information data outputs to be output to such an extent that the processing capability of printing and data transmission by the typewriter can withstand. In this process, for example, an output command is issued when a predetermined time (for example, one cycle) has elapsed after the detection of an accident. When the accident continues, processing such as issuing an output command every one to several cycles is performed as necessary.

Next, the information data calculation processing in step S8 will be described. This processing can output various forms of information data, such as Expressions (5) to (9), but Expression (5) will be described as an example. (5) the reference voltage data v ₁ to v ₁₂ as data of the reference voltage _P by the formula
Are appropriately used, and sample data d _{0-1 to} d _0-12 are appropriately used as data on the amount of electricity during an accident. Information data V _P Ecosθ and V _P Esinθ is determined for example by the following equation.

However, for the data of d _0-1 and d _0-4 , the above operation is performed for each data corresponding to each of the voltages e _{1 to} e ₆ . Ie
performs the operation on data corresponding to e _1, sequential e _2, e _3,
The above operation is performed using the data of e ₄ , e ₅ and e ₆ .

The operation of the above embodiment will be described. During the normal operation of the power system, the accident detection in step S4 in FIG. 2 is not performed, and the processing flow of steps S2-S3-S4-S5-S6-S11 is repeated.
During this time, the sample data d _{0-1 to} d _1-12 and the reference voltage data v _{1 to} v ₁₂ are constantly updated and stored. No information data is output.

When an accident occurs in the power system, an accident is detected in step S4, and the processing flow first repeats S2-S3-S4-S7-S10-S11. During this time, the sample data d _{0-1 to} d _1-12 are successively updated to the values after the accident. However, the reference voltage data v _{1 to} v
Step ₁₂ is the processing of equation (12), and no new data is taken. In the process known digital processing type relay, fault detection is usually so performed 1 cycle following times after the accident occurs, the reference voltage data v ₁ to v ₁₂ remains storing accident data before.

The process flow from step S7 to S10 once, for example, one cycle after the detection of the accident while the accident continues, is changed to the process flow of steps S7-S8-S9-S10 according to the output command in step S7. This change is made every time there is an output command in step S7. Due to this change, the processing of equations (13) and (14) is performed in step S8, and
_{a, b, c, a,} for all the case of the _b and _c, individually V _P E _COS θ and V _P E _sin θ is calculated. Further, in step S9, these calculated values are output as information data.

Equations (13) and (14) are explained as follows. That is, the value of each data is the instantaneous value of the sinusoidal waveform V _P and E
Given by the effective value of

Here, ω is an angular velocity, t is time, α is an angle determined at the time of sampling, and π is a pi.

Data v ₁ and d _0-1 are data sampled 2 / π after v ₄ and d _0-4, respectively, and data v ₁ and v ₄ are integer multiples of d _0-1 and d _0-4, respectively. Is the data sampled before the cycle of and is given by the above equation.

From equation (15) Therefore _{v 1 d 01 + v 4 d} 04 = 2V P E COS θ ... (17) becomes, the (13) equation is obtained.

Also, from equation (15) Therefore And the equation (14) is obtained.

Since the size of the accident before the reference voltage V _P is generally obtained as the information for the operating conditions at all times of the power system, as long the information is obtained it is possible to calculate the E _COS theta and Esinθ electric quantity The magnitude and the phase angle θ with respect to the reference voltage _P can be calculated.

Further, it calculates the magnitude V _P of the reference voltage by means such as shown in the references shown in the modified example described below, it is easy to output the value as the information data.

(Modification 1: V _P EcosE, calculating means V _P Esinθ) above (13) and (14) is V _P Ecosθ and V _P Esin
It is merely an example of the calculation means of θ, and there are various calculation means.
An example is shown below.

In _{V P Ecosθ = v 1 d 01} -v 2 d 02 + v 3 d 03 ... (20) V P Esinθ = v 1 d 02 -v 2 d 01 ... (21) the above equation, So that From equations (16) and (24) Therefore, the expression (20) is obtained from the expressions (24) and (25).

From equations (15) and (23), Therefore And equation (21) is obtained.

More Besides there are means for calculating the V _P Ecosθ and V _P Esinθ, the present invention is not limited to the calculation means of the embodiment.

(Modification 2: Ecosθ, outputs Esinshita) information data of the invention said V _P Ecosθ and V _P Esinθ
The present invention is not limited to this, and various modifications can be made. These examples will be described one after another.

Computation result of V _P Ecosshita and V _P Esinshita the reference voltage _P
After calculating the size of , The values of Ecos θ and Esin θ can be output as information data. Ecosθ and
Esin indicates the real number and the imaginary number of the electric quantity when the reference voltage is _P, and the phase angle relationship between them can be known.

The magnitude of the reference voltage V _P or a square V _P ² (V _P ² if the Rarere obtained V _P is obtained by calculating the square root) the calculation method seeking References 1 page 112 and references 2 Of 16
Since it is described on pages 23 to 23, the description is omitted for simplicity.

Information data output, after calculating V _P ² by the method of the reference, By performing the calculation of, Ecosθ / V _P and Esin θ / V _P
Value. Even with this information data, V _P Ecosθ
And V _P Esin θ can be used to calculate the magnitude of the quantity of electricity and the phase angle θ with respect to the reference voltage _P in the same manner as when the information data is used.

(Modification 4: sinθ (or cosθ) and tanθ (or c
otθ) is output) The information data output is calculated by calculating the effective value E of the quantity of electricity during the accident by means of the reference shown in Modified Example 2 and dividing equation (28) or (29) to obtain cos θ or sin θ. And the trigonometric functions tan θ and cot θ of the phase angle θ can be calculated by the following equation.

Although both tanθ and cotθ may be output as information data, only one of them can be output by the following means.

(B) When V _P Esin θ ≤ V _P Ecos θ, calculate equation (32) and tap
Output nθ.

(B) When V _P Esinθ> V _P Ecosθ, calculate equation (33) and
Which of tanθ or cotθ that outputs tθ is output can be identified by a sign bit.

By outputting the information data of cos θ (or sin θ) and tan θ (or cot θ) calculated by the above means, the angle θ of the electric quantity with respect to the reference voltage _P can be known.

(Modification 5: Output θ) In the above embodiment, cos θ (or sin θ) and tan θ (or c
otθ), the phase angle θ can be calculated by storing a trigonometric function table in the memory.

(Modification 6: Method for Identifying Command Device) FIG. 3 is a diagram showing a configuration of another embodiment of the present invention.
In the figure, the same parts as those in FIG. 1 are indicated by the same symbols. 9 is an input device, and 10 is a command device. The input device 9 is similar to an input device used in a normal computer, and when receiving a command signal from the outside, causes the computer to execute processing corresponding to the command. The command device 10 is provided externally or remotely. Commands are often sent by the command device 10 via transmission means such as a microwave communication device or an optical communication device, but are omitted for simplicity.

Other configurations are exactly the same as those in FIG. One embodiment of the processing flow of the command device 10 will be described with reference to the drawings. In FIG. 4, the same processing parts as those in FIG. 2 are indicated by the same symbols. Steps S1 and S2 as in FIG.
If the scheduled time has not elapsed since the start, the process proceeds to step S11, and the sample data is rewritten according to the equation (10). If the scheduled time has elapsed after the start, an accident detection process similar to that of FIG. 2 is performed in step S4. If the accident detection is not performed, after performing the accident-free processing of step SG1 shown in detail in FIG. 5, the processing of step S11 is performed. Step SG1 will be described later.

If an accident is detected, an accident detection signal is output in step S12, and it is determined in step S13 whether or not a holding command is stored. If not, a holding command is stored in step S14. Further, a time count (T ₁ ) is performed in step S15. If the hold command is stored, step S13
And the processing of S14 is omitted.

After performing the time counting T ₁ at step S15, the count value T ₁ moves to step S16 to determine whether or not reached a predetermined value, moves to step S11 when not reached the predetermined value. When the count value T ₁ is has reached a predetermined value outputs an output command signal in step S17, further step S18 proceeds to step S11 after resetting the count value T ₁ to 0.
After performing the process of step S11, the process moves to step S2 and the above-described process is repeated. By the above processing, the period of the fault detection is performed fault detection being performed, it outputs the accident detection signal, and also sends an output command signal every time the count T ₁ reaches a predetermined value.

After the accident is recovered, no accident is detected in step S4, and the process proceeds from step S4 to step SG1.
Details of the processing in step SG1 will be described with reference to FIG. First, in step SG1-0, it is determined whether or not the holding command stored in step S14 is stored. Fault detection in step S4 is performed immediately after it is restored, the holding Directive remains stored, outputs the accident detection signal in step SG1-1, performs transfer time count T ₂ in step SG1-2. Further the count value T ₂ is determined whether reaches the predetermined value in step SG1-3, proceeds to step SG1-4 does not reach the predetermined value. Count value T ₃ in step SG1-5 after performing a time count T ₃ in step SG1-4
It is determined whether or not has reached the scheduled value. If the predetermined value has not been reached, the process of step SG-1 ends, and the process proceeds to step S11 in FIG.

If the accident continues to recover, steps S11 and S in FIG.
After the processing of 2, S3 and S4 is performed, step SG-
1 is performed. At this time, the count values T ₂ and T ₃
And T ₃ are both the same process as the re-does not reach the predetermined value is repeated. After this process is repeated, the count value T ₃ reaches the predetermined value. (Count value T ₂
The predetermined value is sufficiently larger than the expected value of the count value T _3). Thus, after processing of step SG1-5, step SG1-6 is performed.
Outputs transfer output command signal to the further resets the count value T ₃ to 0 in step SG1-7. Thus the count value T ₃ in the outputs an output command signal every reach predetermined value. Count value T ₂ is reached predetermined value while repeating this, when it is detected in step SG1-3, further steps S resets the memory of the holding command at step SG1-8
Resets the count value T ₂ in G1-9. When the storage of the hold command is reset, this is detected in the processing of step SG1-1, and no other processing is performed.

As described above, the time count T ₂ after the accident detection is restored
There until time to reach predetermined value, the fault detection signal is output also time count T ₃ output command signal every time to reach predetermined value is output.

The input device 9 shown in FIG. 3 receives the accident detection signal and the output command signal output from the command device 10, and notifies the microcomputer 5 of the signal reception status. The processing of the computer 5 is not based on its own calculation in step S4 of FIG.
The process is the same as the process in FIG. 2 except that the output command in step S7 is processed depending on whether or not the output command signal has been received.

As described above, in this embodiment, the command device is separately provided, the information data output device holds the data of the reference voltage _P by receiving the accident detection signal from the command device, and the information data output device receives the output command signal. Is output. In this embodiment, the period of the information data output during accident Sadamari in time count T _1, the period of the information data output after the accident recovery is determined by the time count T _3. An example of this cycle is 0.0167-0.4 seconds during an accident and 0.1-0.
2 seconds. This corresponds to the fact that an accident is interrupted generally in about 0.1 second or less, and the power fluctuation after the recovery from the accident occurs, for example, every 1 second. As described above, the present embodiment has an advantage that the output period of the information data can be made suitable for each of during and after the accident.

In the processing shown in FIG. 4, the command device sends out both the accident detection signal and the output command signal, but this can be implemented by sending only the accident detection signal. FIG. 6 shows an embodiment of the processing of the command device in such a case.
4 and FIG. 4 are denoted by the same symbols. After the initialization process is completed and the elapse of the scheduled time is detected in step S3, the detection process in step S4 is performed, and if an accident is detected, an accident detection signal is output in step S12. This accident detection signal is stopped as soon as the accident is no longer detected.

FIG. 7 is a diagram showing an example of a processing flow of information data output when the processing of FIG. 6 is used. Figure 2
4 and 5 are denoted by the same symbols,
The differences from the figure will be described. When the elapse of the scheduled time is detected in step S3, the process proceeds to step S19. Here, if no accident detection signal is received, the process proceeds to step S21. Unless the change without color reception there of the fault detection signal is not within the time T _2, the rewriting of the reference voltage data by (11) in step S5, the creation of the reference voltage data v ₁ in step S6,
In step S11 (10) of the sample data by the equation rewritten, the flow returns to step S3 after performing the uptake of sample data d _0-1 at step S2. The above is repeated as long as no accident detection signal is received.

When fault detection signal is received, counting the time T ₁ proceeds from step S19 to step S15. When the count value reaches the predetermined value, the count value of the time T ₁ at step S18 is reset to 0, performs operations similar information data and the case of FIG. 2 at step S8, outputs the calculated value in step S9 I do. Further, when the count value of the time T ₁ is not reached the predetermined value passes to step S20, detects whether trip command output is available to the (0 → 12) vary from no for breaker. If this change is detected, step
The processing of S18 → S8 → S9 is performed in the same manner as described above. If the above detection is not performed in steps S16 and S20, these processes are not performed. If an accident detection signal is received in step S19, regardless of the presence or absence of the processing in steps S18, S8, and S9, step S1 follows the processing.
Move to 0, rewrite the reference voltage data according to equation (12), and then perform steps S11 and S2.
Return to S3. This process is repeated as long as the reception of the accident detection signal continues.

After lost reception of the fault detection signal until after the time T ₂ are, proceeds to processing in step SG1-4 through step S12 from the process of the step S19. Here we perform a counting time T _3, identifies whether or not the count value in step SG1-5 has reached the predetermined value. If the count value has reached the expected value, the count value is reset to 0 in step SG1-7, and the information data is calculated in step S22.
The calculated value is output in step S23. When the count value has not reached the predetermined value of the time T _3, SG1-7, S22 and
The processing of each step of 23 is not performed. In any case, after these processes, the process returns to step S3 after the data rewriting processes in steps S10, S11, and S2.

As described above, in the embodiment of FIG. 7, the rewriting process of the reference voltage data changes from step S5 and S6 to step S10 due to the reception of the accident detection signal, and the data before the reception of the accident detection signal is held for a predetermined period. Become like Thus, the data before the occurrence of the accident is held as the reference voltage data. The retention of the data is performed by the scheduled time T ₂ after the lost reception of fault detection elapses.

In a state where there is a reception of the fault detection signal, for each predetermined value of the time T ₁ Ri count, and instantly information data trip command output is issued to the circuit breaker is output. Also,
When receiving the fault detection signal is lost, until passage of time T ₂ from being lost sends the information data output every predetermined value of the count of time T _3.

As described above, the information data output device is configured to receive an accident detection signal from another without owning the accident detection device, and to hold the sample data of the reference voltage _P by receiving this signal. Even so, the object can be achieved in exactly the same way.

(Modification 7: Reference Voltage _P and Electricity) In the embodiment of FIG. 1, as an example of the voltage used as the reference voltage _P , a voltage relative to a relative ground voltage _a or a-b phase voltage
_The case where _ab was used was shown. However, there are various other voltages that can be used as the reference voltage _P , and other various relative ground voltages, inter-phase voltages, or various voltages obtained by variously combining the respective phase voltages can be used. Before the accident, the voltages are almost balanced in three phases, so there is almost no difference in operation regardless of the voltage used unless a voltage with a very small value such as a negative-phase voltage or a zero-phase voltage is used. .

Generally, the voltage or current of each phase is used as the quantity of electricity. Of course, other electric quantities such as a difference between two-phase voltages or currents and a sum of three-phase voltages or currents (three times as much as zero phase) can be used according to the purpose. Further, when data for stability is particularly required, data of only the positive-phase voltage and the positive-phase current may be output to reduce the amount of output data.

An example of a processing method for outputting data of the positive-phase voltage will be described. An example of a method for determining the quantity of electricity as a positive phase voltage _a1 a-phase reference (5) of V _P V _a1 cos [theta] and V _P V _a1 sin [theta is the computation of the following equation.

d _{0-3 (va1)} and d _{0-6 (va1)} are sample values that would be obtained if the voltage _a1 were directly sampled at the same time as the sample data d _0-3 and d _0-6 , respectively. _{0-1 (vc)} and -d
_{0-4 (vc)} each sample data d _0-1, the voltage _C of the data in d _0-1, d _{0-3 (va)} and d _{0-6 (va)} each sample data d
Data of voltage _a in _0-3 and d _0-6 , d _{0-5 (vb)} and d
_{0-8 (vb)} is the voltage in sample data d _0-5 and d _0-8 , respectively
_b .

The V _P of each data value, V _a, V _b, and when the V _c and each of the effective value, is expressed by the following equation.

Where θ _a , θ _b , θ _c are the phase angles of _a , _b , _c with respect to _P. Becomes Becomes Therefore, From the relationship However, θ _a1 is the phase angle of _a1 with respect to _P.

Becomes Becomes Therefore, from the relationship of equation (41), Becomes

(38) from v ₃ and v ₆ (42) and (45) below the formula Therefore, v ₃ d _{0-3 (va1)} + v ₆ d _0-6va1 = 2V _P V _{a1 cosθ a1} (48) Therefore, v ₃ d _{0-6 (va1)} −v ₆ d _{0-3 (va1)} = 2V _P V _a1 sin θ _a1 (51), and V _P V _a1 cos θ and (35) are calculated by the equations (34) and (35). V _P V _a1 sin θ is calculated.

The positive phase voltage can also be used as the reference voltage _P. In this case, since the data d _0-3va1 obtained by the equation (36) is a sample value of the positive-phase voltage _a1 at the sampling time of the d _0-3 sample data, the data obtained by _{sequentially feeding} this is used as the reference voltage data. based on the positive phase voltage _a1 of before the accident if the voltage _P
Is calculated.

(Modification 8: A voltage that simulates a voltage at a specific point on a transmission line is used as a reference voltage _P. ) In the above-described embodiments, an electric station that acquires information data of electric quantity (referred to as a data acquisition electric station) The voltage itself is used as the reference voltage _P. However, the reference voltage _P can be a voltage that simulates the voltage at a specific point J on the transmission line that is drawn from the data acquisition power station. Such a voltage is simulated by the following equation. _P = _S − _S (52) where _S is the voltage of the data acquisition power station, _S is the current of the power transmission line drawn from the power station, and is the distance between the specific point J on the power transmission line and the power station. This is the transmission line constant.

In the present embodiment, the sample value of the voltage _{P in} the equation (52) is calculated by calculation from the sample values of the voltage _S and the current _S , and the calculated sample value is used as the sample value of the reference voltage _P. .

This embodiment corresponds to step S6 of the embodiment of FIG. 2 or FIG.
Only it is carried out in changing the creation of reference voltage data v ₁ at. Data v ₁ is calculated, for example, by the following equation.

_{v 1 = A r v s (} 1-12) + A i v s (1-9) - (Z r i s (1-12) + Z i i s (1-9)) ... (53) However, A _r , A _i , Z _r and Z _i are a constant and a constant and an imaginary part, respectively, and their relations are expressed by the following equations.

Further, vs _(1-12) , is _(1-12) , vs _(1-9), and is _(1-9) are the voltages _{S1 of the} data _d1-12 and _d1-9 , respectively. And current
_{This is} the data of _S. As the voltage _S and the current _S , those of various phases among the three phases are used. For example a-b interphase voltage _a - _b the current of the current _S also a-b interphase when used as _{s a} - and is _b, the data _{v s (1-12), v s} (1-9), i s _(1-12) and is _(1-9) are each a
It is obtained as a value obtained by calculating the difference between the data of the phase voltage _a and the b-phase voltage _b or the data of the a-phase current _a and the b-phase current _b . In addition, as the voltages _S and _S , for example, a voltage _S and a current _S may be referred to as a-phase voltages _a and a, respectively.
A phase current _a , or a positive phase voltage based on each a phase
_a1, there are various means, such as a positive-phase current _a1. Of these, the sample values of the positive-phase voltages _a1 and _{a1 based on} the a-phase are obtained by adding data at different times, as in the case of Expression (36).

These data v ₁ which is calculated as an example, like the other embodiments shown in FIG. 2 or FIG. 7, step S5
Is rewritten one after another by (11), and the reference voltage _P
Is used as the data.

Next, equation (53) will be described. In the right side of equation (53), the product A _r v
_{s (1-12)} and Z _r i _{s (1-12)} is at the sample time of the data d _1-12 (hereinafter referred to as time 1-12) product A _{r S} and Z _r
Equal to the sample value of _S. Also, the data vs _(1-9) and i
The sampling time of _{s (1-9)} is 90 ° after time 1-12.
Therefore the value of the data v _{s (1-9)} and i _{s (1-9)} is equal to the sampled each voltage j _S and j _s time 1-12. Therefore, the product A _i v _{s (1-9)} and Z _i values of i _{s (1-9)} is equal to each value sample the product jA _{i s} and JZi _s time 1-12.

From the above relationship, (53) where the value of v ₁ = Time - - _{(s s)} 1-sample values in _{[A r s + jA i s (} Z r s + jZ i s) ] Time 1-12 = Sample value at 12 ... (55) Therefore (53) data v ₁ of the formula, (52) equal to at the sample value at time 1-12 reference voltage _P of expression.

It should be noted that a general transmission line in which the influence of the charging current of the transmission line portion can be ignored can be treated as ≒ 1 in many cases.
(53) often calculates data v ₁ as Ar = 1 Ai = 0 in formula.

The effect of using the voltage _P in equation (52) as the reference voltage will be described. Each terminal A, B and C of the transmission line L in FIG.
Consider a case where the present embodiment is provided in an electric station having a location. In this case, at the substation at the terminal A, the voltage _s and the current
_{Let s be} the voltage _A and the current _A of the terminal A, and let the constant be the constant between the terminal A of the transmission line L and the branch point J (for example, let 1 be _AJ ) and apply equation (52) , The reference voltage _P is a voltage that simulates the pre-accident voltage at the branch point J. Similarly, at the terminal B and the terminal C,
By applying equation (52) to simulate the voltage at junction J, the reference voltage simulating the pre-accident voltage at junction J
_P is obtained.

When applied in this manner, the reference voltages _P at the electric stations at the terminals A, B and C are all the same. For this reason, all the information data output from each of the electric stations is data based on the same reference voltage, so that it is possible to obtain information data from which the phase relationship between the electric quantities at different electric stations can be easily known.

In the case of the two-terminal transmission line shown in FIG. 8, by applying this embodiment only to the electric station of one terminal, the reference voltage _P at the electric stations at both ends can be the same voltage. That the substation terminal A of FIG. 8, (52) equation by applying the present embodiment the constant and as a constant between the terminals A-B of the transmission line L, the reference voltage _P of substation terminal A
Is a voltage that simulates the voltage before the accident at the electric station at terminal B.

As described above, in the present embodiment, the sample value of the reference voltage _P is set to the sample value of the voltage simulating the voltage at the specific point J on the transmission line according to the equation (52), so that the arrangement of each terminal of the same transmission line is performed. The reference voltage _P of the substations to be used is the same, and information data based on the same reference voltage can be obtained from each substation.

Also in this case, it is effective to set the sample value of the reference voltage _{P to} the value immediately before the occurrence of the accident, as in the other embodiments. That is, the voltage at the specific point J can be simulated by the equation (52) when the circuit breaker of the transmission line between the specific point J is closed and there is no accident between the specific point J and the transmission line. is there.
With the voltage after the occurrence of the accident, it is often impossible to simulate the voltage at the specific point J because there is an accident with the specific point J or the transmission line is cut off.

〔The invention's effect〕

According to the present invention, the instantaneous value waveform of the voltage or current is output simply by outputting simple information data without using a large amount and high-speed transmission means such as PCM or frequency modulation, and a plurality of waveforms are output during or after an accident in the power system. There is an advantage that information data that can easily clarify the phase relationship between the electric cars of the electric station can be obtained.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of one embodiment of the present invention, FIG. 2 is a diagram showing a processing flow of one embodiment of the present invention, FIG. 3 is a diagram showing a configuration of another embodiment of the present invention, FIG. 4 is a diagram showing a processing flow of another embodiment of the present invention, FIG. 5 is a diagram showing a detailed processing flow of a part of FIG. 4, and FIG. 6 is an accident detection in another embodiment of the present invention. FIG. 7 is a diagram showing a processing flow when only a signal is transmitted, FIG. 7 is a diagram showing an example of a processing flow of information data output when performing the process of FIG. 6, and FIG. 8 is an accident point in a two-terminal transmission line. System diagram for explaining the orientation problem, ninth
The figure is a vector diagram for explaining the problem of fault location in the system of FIG. 8, and FIG. 10 is a system diagram for explaining the problem of fault location in other terminal transmission lines. 1-1 to 1-6 Input converter 2-1 to 2-6 Sample hold circuit 3 Multiplexer 4 Analog to digital converter 5 Microcomputer 6 Random access memory 7 Read Only memory 8 Output device 9 Input device 10 Command device

Claims (4)

(57) [Claims] An information data output device for a power system, which is provided at each of a plurality of electric stations and outputs a value related to an electric amount after detecting an accident in the electric power system as information data, comprising: Means for periodically sampling and inputting, reference voltage data creating means for extracting or creating common reference voltage data at a plurality of electric stations from the received electrical quantity, and reference voltage data from the reference voltage data creating means. A data rewriting means for periodically updating stored data in which electric quantity data from the fetch means is held for a predetermined period; and stopping the update of the reference voltage data after detecting an accident in the power system to retain data before the accident. A reference voltage data holding unit, and using the reference voltage data and the electric quantity data to generate a common reference voltage _P at a plurality of electric stations of the electric quantity. Information data calculating means for calculating a phase angle θ or a plurality of function values capable of specifying the phase angle θ, and a reference voltage _P common to the plurality of electric stations.
Output means for outputting information data calculated by the information data calculation means for obtaining a phase relation between a plurality of electric power station electric quantities from the phase relation of the electric quantity with respect to the electric power system. Output device. 2. The power system information data output device according to claim 1, wherein one of the plurality of functions capable of specifying the phase angle θ includes sin θ and the other includes cos θ. . 3. One of a plurality of functions capable of specifying the phase angle θ is one of cos θ or sin θ, and the other is tan θ or cot θ
The information data output device for a power system according to claim 1, wherein the information data output device includes one of the following. 4. The reference voltage data of a reference voltage _P created by said reference voltage data creating means is a voltage _{S of} an electric station for calculating information data of an electric quantity, a current _{S of} a transmission line drawn from the electric station, and Claims characterized by simulating a voltage at a specific point J of a transmission line between substations according to a transmission line constant between substations, and using the same as reference voltage data at each substation. The information data output device for a power system according to item (1). _P = _S − _S