JP3272905B2 - Inspection test equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a phase test apparatus for performing a phase test of a polyphase AC such as a three-phase AC between electric power stations.

[0002]

2. Description of the Related Art An electric power transmission system is composed of a plurality of power stations, substations and the like (hereinafter collectively referred to as "electric stations") and transmission lines connecting the electric stations.

A power plant is provided with a generator, and a substation is provided with a transformer as a main engine. In addition, in order to send more stable and high-quality electricity to the power grid with these main engines,
Protection relay device, measurement and monitoring device as protection and security equipment,
An instrument transformer and an instrument current transformer for installing a circuit breaker, etc., and converting and applying the transmission voltage and transmission current to a low level suitable for measurement by protective relays and measuring / monitoring devices. Is installed.

[0004] By the way, when new construction or repair work of an electric substation or transmission line is performed, a transmission line connecting between electric substations at the final stage of the completion inspection, an electric plant where new construction or repair work is performed (hereinafter referred to as "new electric substation"). In all cases, including the main engine and protection / security equipment, the three-phase AC circuits related to the main circuit of power transmission (hereinafter referred to as “transmission line”) are connected in accordance with the correct phase order and polarity. A test (hereinafter, referred to as a “phase check test”) is carried out for confirmation.

[0005] Conventionally, during a phase detection test between devices installed in one new electric substation, since the connection between the devices is limited to the substation, the device that becomes the reference side of the measurement and the device to be measured are connected. Input each voltage (secondary voltage of the instrument transformer) or current (secondary current of the instrument current transformer) of one set of equipment to a set of measuring equipment and compare the measured values to perform the test. However, for the phase test between electric stations located at remote points from each other (hereinafter referred to as "phase test between electric stations"), the electric station on the reference side (hereinafter referred to as "existing electric station") It was difficult to compare and test the voltage of the device at the new electric station on the measured side.

In this case, while making a telephone call between the two substations, the existing substation switches the connection of the power transmission terminals of the three-phase AC transmission line to transmit power to the new substation on a phase-by-phase basis. At the same time, the secondary voltage of the measuring transformer in the local station of the transmitting phase is measured, and at the new electric power station, which phase of the three-phase AC transmission line is receiving the power including the corresponding phase is included. A qualitative method has been adopted in which all the phases are checked by measuring the secondary voltage of the in-house instrument transformer, and this is repeated for the three phases of the existing electric station.

However, in this method, the transmission voltage of the existing electric station (secondary voltage of the transformer for the instrument) is directly compared with the receiving voltage of the new electric station (secondary voltage of the transformer for the instrument),
It is impossible to measure the phase difference and the difference voltage, and it takes time and effort to switch the three-phase AC transmission line for each phase and to confirm by telephone, and also to perform erroneous operation by the operator. In order to prevent erroneous test results from being output due to miscommunication, misjudgment, miscalculation of measurement data, etc., each work requires extra caution.
The disadvantage is that it takes a long time to test.

[0008] In particular, for the above-described one-phase power transmission to the new electric power station, the operator first opens the circuit breaker, confirms that the power transmission line is not charged, and then climbs to a high place to open the power transmission terminal. In addition, the work of switching the connection, turning on the circuit breaker again, and transmitting power to another phase is repeated at least three times for one three-phase circuit. There was a danger in power detection work and the like.

[0009] In recent years, as the linkage of the transmission system becomes more complicated, a faster, safer, more reliable and more reliable quantitative phase test is also indispensable in the phase test between substations. Become. Also, from the viewpoint of stable supply of high-quality electricity, there should be no power outage accidents due to test errors, and it is necessary to establish a quantitative test method that can perform tests easily and quickly and that has high reliability of test results. Have been.

[0010]

SUMMARY OF THE INVENTION An object of the present invention is to provide a phase detection test apparatus which can perform a test easily, quickly and safely and has high reliability of test results. Another object of the present invention is to provide a phase detection test apparatus that can achieve the above object without using advanced technology.

[0011]

This and other objects are achieved by the present invention which is defined below as (1) to (11).

(1) Regarding the multi-phase alternating current between the transmission power station and the receiving power station located at remote points from each other, the first secondary voltage of the polyphase alternating current in the instrument transformer installed in the transmission power station and the above A phase detection test apparatus that performs a phase detection test based on a second secondary voltage of polyphase alternating current in an instrument transformer installed at a receiving power station, wherein the first secondary voltage is transmitted to the transmission power Transmission means for transmitting to the power receiving station for each phase using a communication cable having a known electrical characteristic between the power receiving station and the power receiving station,
Measuring means for measuring the transmitted first secondary voltage and the corresponding second secondary voltage, and correcting means for correcting changes in voltage and phase due to electrical characteristics of the communication cable. The correction means treats the communication line as an infinite-length line by terminating a receiving end of the communication line in the receiving power station with a characteristic impedance, and Using a formula for calculating the voltage attenuation and phase rotation on the communication cable with the length as a variable, the first secondary voltage is compared to the communication cable for the first secondary voltage at the receiving end. The first secondary voltage applied to the transmitting end of the power transmission substation of the working line is determined by performing a correction in consideration of the amount of attenuation of the voltage attenuated according to the length of the voltage, and transmitted to the receiving end. Was done A second secondary voltage of the power receiving substation measured using the secondary voltage of 1 as a phase reference, and a phase value of the voltage at which the first secondary voltage is generated according to the length of the communication cable. A phase detection test apparatus for performing a correction in consideration of rotation to obtain a phase difference between a first secondary voltage at the transmitting end and a second secondary voltage at the power receiving substation.

(2) The correction means further includes a first secondary voltage at the transmitting end or the receiving end, the phase difference, and a second secondary voltage measured at the power receiving substation. The phase detection test device according to the above (1), wherein a difference voltage between a first secondary voltage of the transmission power station and a second secondary voltage of the power reception power station is obtained from the following.

(3) The measuring means is for obtaining a difference voltage and / or a phase difference between the first secondary voltage and the second secondary voltage from the first secondary voltage and the second secondary voltage. A phase detection test apparatus according to item 1.

(4) The detection method according to any one of (1) to (3), wherein the transmission means sequentially transmits the voltage of each phase and the line between the polyphase alternating currents in a predetermined order. Phase test equipment.

(5) The detection device according to any one of (1) to (4), wherein the transmission means transmits the first secondary voltage using one line of the communication cable. Phase test equipment.

(6) The transmission means has a step-down means, and the step-down means transmits the first secondary voltage by lowering the voltage so as to match a rated use voltage of the communication cable. The phase detection test device according to 5).

(7) The phase detection test apparatus according to (6), wherein the step-down means is an insulation type transformer.

(8) The first transmission from the transmission substation
The phase detection test device according to any one of the above (1) to (7), further comprising identification means for identifying a phase of the secondary voltage and a phase of the first secondary voltage transmitted at the power receiving substation. .

(9) The identification means includes a phase selection means for selecting a phase of the first secondary voltage to be transmitted or a combination thereof, and a phase selection command means for transmitting a phase selection command signal to the phase selection means. And the phase selecting means is configured to select the phase or a combination thereof in accordance with the input command signal.

(10) The phase detector according to (9), wherein transmission of the command signal to the phase selection means and transmission of the first secondary voltage to the power receiving substation are performed on the same line. Testing equipment.

(11) The phase detection test apparatus according to the above (10), further comprising a discriminating means for discriminating the command signal and the first secondary voltage.

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

In general, a transformer for an instrument is installed in an electric substation, and the transmission voltage (primary voltage) of the three-phase AC transmission line is 63.5 V or 110 V (effective value) by the instrument transformer.
The measurement and monitoring are performed for the purpose of protection and security by using the lowered three-phase AC low voltage (secondary voltage).

In the present invention, when conducting a phase detection test between substations,
At the transmission substation (existing substation) that is both the transmission side of the transmission line and the reference side of the measurement, the voltage of the transmission line is stepped down by an instrument transformer and the first secondary voltage (reference voltage) of three-phase AC is reduced. ) On the other hand, at the receiving substation (new substation) which is both the receiving side and the measured side of the transmission line,
The voltage of the transmission line is stepped down by an instrument transformer to obtain a second secondary voltage of three-phase AC, and the transmission means transmits the first secondary voltage for each phase to a receiving power station. The transmitted first secondary voltage and the second secondary voltage are measured by measuring means provided at the place, and the difference voltage and the phase difference between these are measured. In this case, a phase detection test is performed with the power transmission system between the power transmission power station and the power receiving power station connected to all three-phase AC phases.

Transmission of the first secondary voltage to the receiving power station is as follows:
Although a dedicated line installed separately may be used, it is performed using the existing communication cable (cable installed for voice and electrical information communication) that connects the power transmission station and the power receiving station. Is preferred. In this case, the first secondary voltage of each phase of the three-phase alternating current can be transmitted through a plurality of lines each having a different communication cable. However, from the viewpoint of effective use of the lines, one line (one round trip pair) is used. It is preferable to use the above-mentioned electric wire. That is, one line is used to sequentially transmit three phases and their line voltages (total of six types) at different times (time sequential transmission method).

In order to adopt such a time-sequential transmission method between a transmitting power station and a receiving power station at remote points,
It is preferable to provide an identification means for identifying a phase of the first secondary voltage transmitted from the transmission power station and a phase of the first secondary voltage transmitted at the power reception power station. Measuring the phase of the obtained first secondary voltage and the phase of the second secondary voltage obtained at the receiving substation accurately
Can be compared.

The identification means includes a phase selection means for selecting a phase of the first secondary voltage to be transmitted or a combination thereof (hereinafter, these are collectively referred to as a “phase”), and a phase selection means for the phase selection means. Preferably, it is constituted by phase selection command means for outputting a command signal. When a command signal for selecting a predetermined phase is output from the phase selection command means, and the command signal is input to the phase selection means, the phase selection means selects a phase corresponding to the command signal. Then, the first secondary voltage of the selected phase is transmitted to the receiving power station via the communication cable.

In the identification means having such a configuration, it is preferable that the phase selection means be installed on the power transmission substation side and the phase selection command means be installed on the power reception substation side, and output from the phase selection command means. It is preferable that the transmission of the command signal to the phase selecting means is also performed by using the same line as the line for transmitting the first secondary voltage of the communication cable. Thereby, the line can be more effectively used.

In this case, because of the difference in the frequency band between the command signal and the first secondary voltage, as a discriminating means, for example, by providing a filter that passes a high band or a low band at these input portions or output portions, Since both can be separated and discriminated, there is no inconvenience due to the dual use of the line.

When transmitting the first secondary voltage to the receiving power station using a communication cable, if the first secondary voltage to be transmitted is equal to or lower than the rated working voltage of the communication cable, the transmission may be performed as it is. However, if the transmitted first secondary voltage exceeds or is likely to exceed the rated working voltage of the communication cable, the transmitted first secondary voltage is reduced by step-down means such as an auxiliary instrument transformer or a voltage divider. It is preferable that the secondary voltage is transmitted after being reduced to a level that matches the rated working voltage of the communication cable. As a result, damage and failure of the communication cable and related equipment can be prevented, and more accurate measurement can be performed.

In this case, it is preferable to use an insulation type transformer as the step-down means, since even if the communication cable or the circuit constituting the transmission means is grounded, it does not affect the power transmission system.

In general, when an AC voltage is transmitted over a communication cable having a finite length, attenuation of the voltage amplitude and rotation of the voltage phase occur due to the electrical characteristics inherent to the communication cable.
Since voltage reflection occurs, an error occurs in the first secondary voltage and the like measured at the receiving power station. In the present invention, in order to eliminate such an error, it is preferable to provide a correction means for correcting a change in voltage and phase due to the electrical characteristics of the communication cable. The details of this correction means are as follows.

The primary and secondary constants of a communication cable are known according to the standard, and the characteristic that the receiving end of a communication line having a finite length at a receiving power station is one of the secondary constants of the communication cable. By terminating with impedance, it can be treated equivalent to an infinite length line,
Therefore, there can be no voltage reflection.

Then, the length of the communication cable (laying distance)
Is used as a variable, a calculation formula for calculating the voltage attenuation and the phase rotation on the communication cable is created, and this calculation formula is stored in advance in a memory of a microprocessor provided in the measuring means, for example. On the other hand, the power receiving station is provided with input means for inputting variables required for calculation, and data (variable x) relating to the length of the communication cable is input from the input means.
Based on the above formula, the first secondary voltage is compared with the amplitude measurement value (V _x ) of the first secondary voltage actually measured at the receiving end of the receiving substation by the length (x) of the communication cable. The first secondary voltage (V ₁ ) applied to the transmission end of the line used in the power transmission substation is obtained by performing a correction in consideration of the amount of voltage attenuated in accordance with the following equation.

The phase value (Φ _x2 ) of the second secondary voltage of the power receiving station measured using the first secondary voltage transmitted to the receiving end of the power receiving station as a phase reference, The secondary voltage of 1 is corrected in consideration of the rotation of the phase of the voltage generated according to the length (x) of the communication cable, and power is received for the _first secondary voltage (V ₁ ) at the transmission end of the power transmission substation. The phase difference (Φ ₁₂ ) of the second secondary voltage (V ₂ ) at the electric station is determined.

Further, the first secondary voltage (V ₁ ) obtained by the correction calculation (or the measured value of the receiving end of the first secondary voltage (V _x )) may be obtained by the same correction calculation. From the phase difference (Φ ₁₂ ) and the second secondary voltage (V ₂ ) measured at the receiving power station, a first secondary voltage at the transmitting power station and a second secondary voltage at the receiving power station are obtained. The difference voltage (V ₁₂ ) from the next voltage is obtained.

By performing the above calculations, it is possible to quantitatively measure the difference voltage and the phase difference by measuring the AC voltage in the phase detection test between substations, and to transmit the first secondary voltage. Since a correction is made to cancel the accompanying change in voltage and phase, the reliability of the measured value is improved, and a more appropriate phase detection test result is obtained.

At the power transmission station, the first secondary voltages of the phases selected one by one are transmitted to the power receiving station via a communication cable based on a command signal from the power receiving station. On the other hand, at the receiving power station, the first secondary voltage for each phase (corrected) transmitted from the transmitting power station and the second secondary voltage of each phase obtained at the receiving power station are used. Measure each,
In addition, by comparing these in a predetermined combination, it is possible to obtain the first secondary voltage and the second secondary voltage of each phase, and also to obtain their difference voltage and phase difference.

The obtained data is displayed on the display means,
Output to the printer as needed. From these data, it is possible to detect the presence or absence of an incorrect connection between the two electric stations (whether or not the three-phase AC circuit is connected according to the correct phase sequence and polarity), and the like. The pattern can also be specified.

[0047]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram showing a preferred embodiment of a phase test apparatus according to the present invention.

FIG. 1 is a circuit diagram showing an embodiment of a phase detection test apparatus according to the present invention. As shown in FIG. 1, a phase detection test apparatus 100 of the present invention is a three-phase alternating current phase test apparatus installed and used between a power transmission station 101 and a power receiving station 102 located at remote points from each other. is there. In this case, the transmission power station 101 is an existing power station, and the power receiving power station 102 is
For example, it is an electric station where new construction, renovation, etc. are performed.

In the power transmission substation 101, circuit breakers CB _1A , C
B _1B and CB _1C are installed. In addition, each phase A, B, C
In the transmission line branching off from the transmission line of
Protective relay device via the 03, the measuring and monitoring device, the protection and safety equipment PRY ₁ circuit breaker or the like is installed. The instrument transformer 103 reduces the transmission voltage (primary voltage) of the power transmission substation 101 to approximately 63.5 V (phase voltage) or 110 V (line voltage), and the first two-phase AC of this stepped-down three-phase AC. Measurement and monitoring are performed using the secondary voltage.

On the other hand, in the receiving power station 102, the circuit breakers CB are respectively connected to the transmission lines of the phases A, B, and C of the three-phase alternating current.
_2A , CB _2B and CB _2C are installed. In addition, each phase A,
In the transmission line branched from the transmission lines B and C, protection and protection devices PRY ₂ such as a protection relay device, a measurement / monitoring device, and a circuit breaker are installed via an instrument transformer 104. The instrument transformer 104 steps down the receiving voltage (primary voltage) of the receiving power station 102 at the same ratio as that of the instrument transformer 103, and measures / reduces the voltage using the reduced secondary voltage of the three-phase alternating current. We are monitoring.

Transmission power station 101 and power reception station 102
During the corresponding phase A, B, C of the transmission line, each transmission line TL _A, TL _B, are connected by TL _C. Further, between the power transmission terminals T _{A1 and} T _A2 provided on the power transmission
Between _B1 -T _B2, between T _C1 -T _C2, when performing Kensho test,
Both are connected.

The phase detection test apparatus 100 of the present invention uses a first secondary voltage (hereinafter simply referred to as a “first secondary voltage”) in an instrument transformer 103 of a transmission power plant 101 as a reference voltage for measurement. This voltage is transmitted to the receiving power station 102 through a predetermined line of the communication cable 20. At the receiving power station 102, the second secondary voltage (hereinafter simply referred to as “second The voltage is measured and compared with the transmitted first secondary voltage (matched).

As shown in FIG.
The transmission means 85 for transmitting the first secondary voltage of the instrument transformer 103 to the receiving power station 102 for each phase, and the first secondary voltage installed and transmitted at the receiving power station 102 and Measuring means 90 for measuring and comparing the second secondary voltage of the instrument transformer 104 corresponding thereto, the phase of the first secondary voltage transmitted from the transmission power station 101, and the transmission at the receiving power station 102 Identification means 80 for identifying the phase of the first secondary voltage thus determined.

The identification means 80 is used to transmit the instrument transformer 1
Phase selecting means 81 for selecting the phase of the first secondary voltage 03
And a phase selection command means 82 for transmitting a phase selection command signal (phase selection information) to the phase selection means 81. These configurations will be described later in detail.

The transmission means 85 steps down the first secondary voltage of the phase selected by the phase selection means 81 as desired and outputs it.
The power is transmitted to the power receiving electricity station 102 via the communication cable 20. In this embodiment, one line (a pair of reciprocating electric wires) of the communication cable 20 is used for transmitting the first secondary voltage. Further, the line (hereinafter referred to as “used line”) of the communication cable 20 is connected to the power receiving electric station 102 of the first secondary voltage.
And transmission of the phase selection command signal to the phase selection means 81. Regarding the configuration of the transmission means 85,
Details will be described later.

The receiving end (termination) of the line used by the communication cable 20 at the power receiving station 102 will be described later as a means for compensating for a change in voltage and phase due to the electrical characteristics of the communication cable. The characteristic impedance 83 is connected.

The measuring means 90 measures a first secondary voltage, a second secondary voltage, a difference voltage and a phase difference between the first secondary voltage and the second secondary voltage, and data of these measurements. (Correction, totalization, etc.), control of phase selection of the second secondary voltage, control of a phase selection command signal transmitted from the phase selection command means 82, display means 106 and a printer The drive control of 107 is performed. This measuring means 90
It has a microprocessor (CPU) 91, and the microprocessor 91 has a built-in arithmetic unit that performs the correction calculation and the like as a component of the correction unit.
The configuration of the measuring means 90 will be described later in detail.

As described above, in the present invention, both electric stations 1
Like actual transmission time of between 01,102, transmission terminal T _A1
-P _A2 , T _B1 -T _B2 , T _C1 -T _C2 can be used to perform a phase detection test while connected, eliminating the need for switching work for power transmission terminals that involves a great deal of labor and danger as in the past. So
The work efficiency and safety of the test are significantly improved.

Hereinafter, the configurations of the phase selection means 81 and the phase selection command means 82 will be described in detail. Phase selection means 81
Is the A of the three-phase alternating current on the secondary side of the instrument transformer 103.
Phase, B-phase, and C-phase voltages, AB, BC, and C
One of a total of six types of phase (line) voltages including the three line voltages of -A is selected. On the other hand, the phase selection instructing means 82 generates a signal indicating that a predetermined phase is selected from the six types of phases, and modulates the carrier with this signal (for example, F
M modulated) and transmits the modulated wave (phase selection command signal) to the phase selection means via the communication cable 20. The phase selecting means 81 demodulates and reproduces an information signal relating to a phase to be selected from the modulated wave received via the communication cable 20, further performs a separate processing on the information signal as six types of phase selection information. By the signal processed separately,
Driving the relay that actually takes charge of the phase selection.

FIG. 2 is a block diagram showing a configuration example of the identification means (phase selection means and phase selection instruction means) in the present invention, and FIG. 3 is a signal waveform diagram in each part of the identification means shown in FIG. Note that the reference numerals in the # symbol column in FIG.
Corresponds to the symbols in the middle. Hereinafter, description will be made based on these drawings.

As shown in FIG. 2, the phase selection instructing means 82
Has a clock pulse generator 1 whose terminal 2
A clock pulse is constantly output as a count pulse of the preset counter 9 (# 2 in FIG. 3). Also, from the terminal 4 of the clock pulse generator 1, a phase designation data setting unit 5
Pulse signal is sent at predetermined time intervals T ₁ to.

The phase specification data setting unit 5 stores data (hereinafter, referred to as “phase specification data”) N _A , N _B , N _C , N _AB , and N _BC relating to the specification of the phase corresponding to the six types of phase voltages _. , N
_CA is stored in advance, and the phase designation data setting unit 5
Are synchronized with the pulse signal from the clock pulse generator 1 to store the stored phase designation data N _A , N _B , N _C , N
_AB, reproduces the N _BC, N _CA, sequentially outputs at intervals of time T ₁ to the terminal 6 (# 6 in Fig. 3). When the control signal for starting the phase selection command (starting the measurement) is transmitted by the phase selection control circuit 94 of the measuring means 90, the phase designation data setting device 5 synchronizes with the pulse signal from the clock pulse generator 1, Phase designation data N _A , N _B , N _C , N _AB , N _BC , N _CA
Is sequentially executed at intervals of time T ₁ , and this sequence operation is performed by changing the phase designation data N _A to N
_The self-stop is automatically performed when the circuit has completed one round to the _CA.
When the control signal for stopping the phase selection command (measurement stop) is sent by 4, the sequence operation is controlled to be stopped.

When the time t ₁ has elapsed since the predetermined phase designating data was output to the terminal 6 of the phase designating data setter 5, the preset pulse is output from the terminal 3 of the clock pulse generator 1 at a constant time interval T ₁ . Then, the phase designation data output to the terminal 6 of the phase designation data setting device 5 is preset in the preset counter 9 (# 3 in FIG. 3). At the same time, the flip-flop 11 is set and its terminal 12
Turn on the output of.

The ON signal at the terminal 12 of the flip-flop 11 becomes a gate signal, and a pulse signal synchronized with the clock pulse # 2 is output to the terminal 8 of the AND gate 7 (# 8 in FIG. 3). This pulse signal is input to the preset counter 9 as a count pulse, and the preset counter 9 starts counting down.

When the data of the preset counter 9 is # in FIG.
As shown in Fig. 9, it decreases and finally reaches "0".
A zero signal is output from the terminal 10 and the flip-flop 11
Is reset, and the output of the terminal 12 is turned off. That is, the phase designation data N _A preset in the preset counter 9 is provided to the terminal 12 of the flip-flop 11.
A square wave having a time length corresponding to N _B , N _C , N _AB , N _BC , and N _CA is output (# 12 in FIG. 3). This square wave is amplified by the buffer amplifier 13 and input to the modulator 16 as a modulation signal which is an information signal for specifying a phase in the phase selecting means 81.

On the other hand, a carrier wave of, for example, about 450 kHz is constantly output from the terminal 15 of the carrier wave transmitter 14 (# 15 in FIG. 3) and input to the modulator 16. From the terminal 17 of the modulator 16, for example, a modulated wave that has been subjected to FM modulation according to the modulation signal is output (# 17 in FIG. 3). The modulated wave is amplified by the amplifier 18, passes through the high-pass filter 19, and is transmitted from the phase selection command unit 82 to the phase selection unit 81 through the use line of the communication cable 20.

The modulated wave transmitted to the phase selecting means 81 is
A demodulated signal, that is, a signal demodulated as a phase designation information signal, is output from a terminal 25 via a band pass filter 21, an amplifier 22, a demodulator 23, and an amplifier 24 (# in FIG. 3).
25), this signal becomes the gate signal of the AND gate 28.

On the other hand, terminal 2 of clock pulse generator 26
7 always output a clock pulse (# 2 in FIG. 3).
7), input to AND gate 28; When the demodulated information signal is input to the AND gate 28, while the information signal is being input, the terminal 29 of the AND gate 28
A pulse signal synchronized with the clock pulse # 27 is output (# 29 in FIG. 3), the input of this pulse signal causes the up counter 30 to start counting up, and the count data output to the terminal 31 becomes # 31 in FIG. Go up as shown.

[0069] The count data as input to one terminal of the comparator 32, while the data (1-p) N _A that is stored in the data memory 33 and outputted from the terminal 34, the other terminal of the comparator 32 Input to.
The comparator 32 constantly compares the two data. When the data N ₁ ′ at the terminal 31 of the up counter 30 matches the data (1-p) N _{A at} the terminal 34 of the data memory 33, the terminal 35 of the comparator 32 Outputs a match signal. In response to the input of the coincidence signal, the flip-flop 36 is set and the terminal 37 is turned on.
The signal indicated by “a” is output.

The coincidence signal output to the terminal 35 of the comparator 32 is also input to the data memory 33,
The output data of the terminal 34 from _{(1-p) N A (} 1-p)
To update to N _B.

The ON output signal of the terminal 37 of the flip-flop 36 is input to the terminal a of the logic circuit 63, while
The signal is input to the AND gate 39 via the delay element 38. The purpose of installing the delay element 38 is as follows.
Is updated from (1-p) N _A to (1-p) N _B , the signal at the output terminal 37 of the flip-flop 36 is changed to the AND gate 39 until the coincidence signal at the terminal 35 of the comparator 32 disappears. To prevent typing and delay.

[0072] In this _{case, (1-p) N A} , (1-p)
_{N B, (1-p)} N C, (1-p) N AB, (1-p) N
_{BC, (1-p) N} (1-p) in each of _{the CA,}
N _A , N _B , N _C , N _AB , N _BC , and N _CA are modulated, transmitted, and demodulated, and the number of pulses is increased due to the asynchronous operation of the clock pulse # 2 in FIG. 3 and the clock pulse # 27 in FIG. It is a coefficient of less than 1 in consideration of the missing, so that even if the number of pulses is at most p × 100%, N _A , N
_B , N _C , N _AB , N _BC and N _CA can be detected.

[0073] In order to secure the discrimination phase specified data, N _A and _{(1-p) N B,} N B and (1-p) N _C,
Between N _C and (1-p) N _AB , N _AB and (1-p) N _BC , and N _BC and (1-p) N _CA , N _A <(1-
p) N _B , N _B <(1-p) N _C , N _C <(1-p) N
_{AB, N AB <(1-} p) N BC, the relationship _{N BC <(1-p)} N CA is kept as established.

[0074] As described above, when the output data of the terminal 31 of the up-counter 30 becomes (1-p) N _A,
Coincidence signal to the terminal 35 of the comparator 32 is output, as well as sets the flip-flop 36, the data terminal 34 of the data memory 33 is updated to (1-p) N _B. Moreover, the (1-p) match signal terminal 35 of the comparator 32 in the N _A is also input to the terminal 73 of the pulse timer 72. Pulse timer 72 generates the phase information read signal to the terminal 70 from obtaining the match signal after a time T ₂ (# 70 in FIG. 3). When the logic circuit (logic and memory circuit) 63 receives the phase information read signal, the phase information signals A, B, C, AB,
Either BC or CA is connected to the corresponding terminal 64, 6
5, 66, 67, 68 and 69 are output. The outputs of these phase information signals are associated with the input information a, b, c, d, e, and f of the logic circuit 63 in the logic circuit 63 using the respective logical expressions shown in the following Expression 1.

[0075]

(Equation 1)

Next, the operation after the AND gate 28 will be described for the case where the phase designation data is N _A. Since the phase designation data is N _A , the AND gate 28 is connected to # 2 in FIG.
T _A shown in 5 'time, it opens the gate to the pulse shape, the up-counter 30 to obtain the pulse signal, N _A 0'
Count up to (the number corresponding to N _A ). Until the count value of the up counter 30 reaches N _A ′, when the count value reaches (1−p) N _A , the comparator 32
Of the flip-flop 36
Is set, and the terminal 37 is turned ON. At the same time, the coincidence signal starts the timer of the pulse timer 72.
Further, this coincidence signal is input to the data memory 33, and the output data of the terminal 34 of the data memory 33 is (1).
-P) is updated from N _A (in 1-p) N _B. By updating this data, the coincidence signal at the terminal 35 of the comparator 32 disappears.

The ON signal of the terminal 37 of the flip-flop 36 is input to the terminal a of the logic circuit 63,
After a predetermined time delay by the delay element 38, the AND gate 39
To one of the input terminals. At this time, the signal to the other input terminal of the AND gate 39, that is, the coincidence signal at the terminal 35 of the comparator 32 has already disappeared.
The state of the terminal 40 of the ND gate 39 does not change at all.

Thereafter, the count value of the up counter 30 becomes
Although it increases to N _A ′, it does not reach (1-p) N _B , so that no coincidence signal is generated at the terminal 35 of the comparator 32 thereafter. Therefore, while only the flip-flop 36 is set, the other flip-flops 41, 4
6, 51, 56 and 61 remain in the reset state.

When a time T ₂ elapses after the internal timer of the pulse timer 72 is started by the coincidence signal at the terminal 35 of the comparator 32, a phase information read signal shown at # 70 in FIG. , To the terminal R of the logic circuit 63. At this time, in the terminals a to f of the logic circuit 63, there is an input to the terminal a, and the logic expression # 64 in FIG. Outputs the phase information signal _A to drive the relay KA for selecting the A phase. Thus, the phase designation data N _A relating to the phase A designated by the phase selection command means 82 and the phase _A selected by the phase selection means 81 are identified.

Thereafter, when a time T ₃ (> T ₂ ) elapses after the internal timer of the pulse timer 72 starts, a reset pulse is output to the terminal 71 of the pulse timer 72 (# in FIG. 3). 71), up-counter 30, comparator 32, data memory 33, flip-flop 36,
41, 46, 51, 56 and 61 are reset, respectively. As a result, the phase information signal A is turned off, the relay K _A also returns, and waits for the input of the next phase information signal.

The time (T ₃ −T ₂ ) during which the phase information signal A is output, that is, the time during which the first secondary voltage related to the phase A is output from the power transmission station 101, is preferably 1. It is about 5 to 6 seconds, more preferably about 1.5 to 2 seconds. The same applies to the other phases described below.

[0082] Then, the phase data specified briefly described for the case of N _B. Up counter 30 is 0 initially counting up from, when the count value reaches (1-p) N _A, as described above, the first match signal is outputted to the terminal 35 of the comparator 32, thereby, the flip The ON signal of the terminal 37 by the setting of the loop 36 is input to the terminal a of the logic circuit 63, the timer inside the pulse timer 72 is started, and the output data of the terminal 34 of the data memory 33 becomes (1-p) N It is updated from _a to (1-p) N _B.

[0083] After the output data of the terminal 34 is updated to (1-p) N _B, continues the count value of the up counter 30 is counted up N _B 'incrementally, during which the count value is (1 -p) upon reaching the N _B, the terminal 35 of the comparator 32, and outputs a match signal again. At this time, since the flip-flop 36 has already been set, the coincidence signal does not change the state, but the AND gate 39 receives the ON signal from the terminal 37 of the flip-flop 36 at one input terminal. Therefore, when this match signal is input to the other input terminal of the AND gate 39, the match signal is output to the terminal 40 and the flip-flop 4
1 is set, and the terminal 42 is turned on. The ON signal is input to the terminal b of the logic circuit 63 and is input to one input terminal of the AND gate 44 after being delayed by the delay element 43 for a predetermined time.

The coincidence signal at the terminal 35 of the comparator 32 is further input to the data memory 33,
Updating the output data of the terminal 34 of the memory 33 (1-p) from the N _B to (1-p) N _C. By updating this data, the coincidence signal at the terminal 35 of the comparator 32 disappears.

Thereafter, the count value of the up counter 30 becomes
Increases to N _B ', but since the (1-p) does not reach the N _C, to the terminal 35 of the comparator 32, subsequent match signal is not generated. Therefore, while the flip-flops 36 and 41 are set, the other flip-flops 46 and 5 are set.
1, 56 and 61 continue to be in a reset state.

Thereafter, when the time T ₂ elapses after the internal timer of the pulse timer 72 is started by the first coincidence signal of the terminal 35 of the comparator 32, the terminal 70 of FIG.
The information reading signal shown at 70 is output and input to the terminal R of the logic circuit 63. At this time, the logic circuit 63
The terminals a to f have inputs to the terminals a and b. In the logic circuit 63, the logic expression # 65 in FIG. and outputs the signal B, and drives the relay K _B to select the B-phase. Thus, B-phase and selected by a phase-specifying data N _B to phase selecting unit 81 about the B-phase specified in the phase selecting command means 82 are identified.

Thereafter, when the time T ₃ has been reached, a reset pulse is output to the terminal 71 of the pulse timer 72 (FIG. 3).
# 71), up counter 30, comparator 3
2, data memory 33, flip-flops 36, 4
1, 46, 51, 56 and 61 are reset, respectively.
As a result, the phase information signal B is turned off, and the relay K _B
Also returns, and waits for the input of the next phase information signal.

When the phase designation data is N _C , N _AB , N _BC , and N _CA , the same operation as in the case of N _B is performed. That is, when the phase designation data is N _C , the data at the terminal 31 of the up counter 30 is stored in the terminal 35 of the comparator 32 as (1-p) N _A , (1-p).
N _B, (1-p) each match signal in N _C outputs, there is the input of the set of flip-flops 36,41,46 terminal a of the logic circuit 63, b, to c, the terminal 66 of the logic circuit 63 the logical output of the logical expression shown in # 66 of FIG. 3, i.e. to obtain phase information signal C, to drive the relay K _C to select the C phase.

When the phase designation data is N _AB , the terminal 35 of the comparator 32 is connected to the terminal 3 of the up counter 30.
1 data _{(1-p) N A,} (1-p) N B, (1-
p) N _C and (1-p) N _AB respectively output coincidence signals, and there are inputs to the terminals a, b, c and d of the logic circuit 63 by setting flip-flops 36, 41, 46 and 51, The terminal # 67 of FIG.
67, that is, a phase information signal AB
And drives the relay K _AB for selecting the AB phase (the line voltage between _AB ).

When the phase designation data is N _BC , the terminal 35 of the up-
1 data _{(1-p) N A,} (1-p) N B, (1-
A coincidence signal is output in each of p) N _C , (1-p) N _AB , and (1-p) N _BC , and flip-flops 36, 4
The logic circuit 63 is set by the set of 1, 46, 51 and 56.
Of the logic circuit 63, ie, a phase output signal BC, ie, a phase information signal BC, is obtained at a terminal 68 of the logic circuit 63. The relay _KBC for selecting the line voltage) is driven.

[0091] When phase designation data of N _CA is in the terminal 35 of the comparator 32, the terminal 3 of the up counter 30
1 data _{(1-p) N A,} (1-p) N B, (1-
p) N _C , (1-p) N _AB , (1-p) N _BC , (1-
p) output by each match signal in N _CA, terminal a of the logic circuit 63 by any of a set of flip-flops 36,41,46,51,56,61, b, c, d,
e and f, and a logic output indicated by # 69 in FIG.
And drives the relay KCA for selecting the CA phase (line voltage of _CA ).

Since the phase detection test device is used at a test site such as an electric substation, it must have improved functionality and measurement accuracy, and be simple in configuration, small in size and light in weight, and easy to maintain. Excellent long-term performance stability,
Low cost is required.

In the present invention, for example, it is possible to assign a different carrier frequency to each signal corresponding to the above-mentioned six types of phase voltages and install six sets of carrier wave transmission circuits and tuning circuits. Although a method of converting the selection command signal or the transmitted phase voltage itself into a digital signal and transmitting the digital signal can be used, in particular, in the phase detection test apparatus 100 according to the present embodiment, the phase to the phase selection means 81 by a single carrier wave. A command signal for selection can be generated and transmitted, and its regeneration, phase selection thereby, discrimination from the first secondary voltage, and the like can be performed by a circuit having a simple configuration. Less
The manufacturing cost of the device is also low, and the above requirements can be sufficiently satisfied.

FIG. 4 is a block diagram showing a configuration example of the transmission means 85 in the present invention. As shown in the figure, the transmission means 85 selects an input section 87 for inputting a first secondary voltage of the instrument transformer 103 and a phase of the first secondary voltage input to the input section 87. Switch circuit 88 and step-down means 8
6 and a low-pass filter 89. The switch circuit 88, the switch S1 is a contact of the relay _{K A ~K CA, S2, S3} , S4, S5, S6, S7, S8
, S9, S10, S11 and S12 are provided.

[0095] When the relay K _A is activated, only the switches S1 and S7 are first secondary voltage of the A-phase is obtained by closing, when the relay K _B is actuated, B phase only switches S2 and S8 are closed A first secondary voltage of
When the relay K _C is activated, the switches S3 and S
When only the switch 9 is closed and the first secondary voltage of phase C is obtained and the relay K _AB is activated, only the switches S4 and S10 are closed and the first secondary voltage of phase AB is obtained and the relay K _BC is obtained _.
Operates, only the switches S5 and S11 are closed to obtain the first secondary voltage of the BC phase. When the relay _KCA is operated, only the switches S6 and S12 are closed and the first secondary voltage of the CA phase is obtained. A voltage is obtained.

The first secondary voltage of each phase output from the switch circuit 88 by driving the relays K _{A to} K _CA is 1 / k by the step-down means 86 (transformation ratio k = about 3 to 6). After passing through a low-pass filter 89, the voltage is applied to the transmission end of the communication cable 20 and transmitted to the measuring means 90 of the receiving power station 102 via the communication cable 20.
Note that k may be constant or variable.

The communication cable 20 has a rated working voltage (standard value), and the first secondary voltage (63.5 V or 110 V) exceeding the rated working voltage cannot be directly applied. The secondary voltage is stepped down by the step-down means 86 to a voltage lower than the rated operating voltage and applied to the transmission end of the communication cable 20.

As the step-down means 86, for example, a transformer or a voltage divider can be used, but an insulated transformer in which the primary side and the secondary side are insulated, especially an auxiliary insulated instrument transformer is used. It is preferably used. Thereby, even if the first secondary voltage causes grounding in the communication cable or the present device, the first secondary voltage does not affect the instrument transformer 103 and other power transmission systems, and the safety is high.

The phase selection command signal transmitted to the transmission power station 101 via the communication cable 20, that is, the modulated wave or the carrier wave has a high frequency (about 450 kHz).
Therefore, the signal is cut by the low-pass filter 89, and is prevented from entering the instrument transformer 103. Similarly,
The phase selection command signal (modulated wave or carrier wave) output from the phase selection command means 82 is cut by low-pass filters 95 and 97 provided in the measuring means 90 described later, and enters the measuring means 90 side. Is blocked.

The first secondary voltage transmitted to the receiving power station 102 by the communication cable 20 is input to the measuring means 90 via the command signal output section of the phase selecting command means 82. Since the secondary voltage of 1 is lower in frequency (50 or 60 Hz) than the command signal, it is cut by the high-pass filter 19 installed in the command signal output unit.
The entry into the phase selection instructing means 82 is prevented.

Similarly, the first secondary voltage output from the transmission unit 85 and output to the communication cable 20 via the phase selection command signal input unit of the phase selection unit 81 is output from the phase selection unit 81. Is cut off by the band-pass filter 21 provided on the side, and is prevented from entering the phase selecting means 81 side.

Such low-pass filters 89, 95,
97, band-pass filter 21 and high-pass filter 1
9 constitutes discriminating means for discriminating the phase selection command signal from the first secondary voltage. In the present invention, the method of discrimination by the discriminating means is not limited to the method based on the difference between the two bands. For example, the method using another signal extraction method or the method using different transmission timings may be used. You may.

As described above, the first secondary voltage of the phase selected by the phase selecting means 81 is
0 is transmitted in the opposite direction to the phase selection command signal by the same line that transmitted the phase selection command signal, but the transmitted first secondary voltage is the second secondary voltage. Since it is a reference for comparison measurement (matching measurement) with the next voltage, it is preferable that the signal be transmitted faithfully in order to perform high-precision measurement.

In general, in a transmission line of a finite length such as a communication cable, voltage attenuation and phase rotation occur due to electric characteristics inherent to the communication cable, and reflected waves are generated. It is difficult to faithfully transmit and reproduce, causing errors in the measured voltages and phases.
Therefore, in the phase detection test apparatus 100 of the present embodiment, a correction unit for correcting such an error is provided. Hereinafter, the principle of the correction by the correction means will be described.

The communication cables used in the power system are usually standardized to a certain standard product, so that the primary and secondary constants of the communication cable can be treated as known constants. Can be handled as a known number.

On the other hand, according to the distributed constant circuit theory of the transmission line, in the infinite length line, since only a traveling wave exists on the transmission line and no reflected wave exists, the voltage (at a distance x on the transmission line) Vector) V _x and current (vector)
I _x is represented by a simple transmission equation (1) using the distance x shown in the following equation 2 as a variable.

[0107]

(Equation 2)

From the above equation (1), the voltage magnitude V _x and the phase rotation Φ _{x at} the distance x are expressed by the following equation (2).

[0109]

(Equation 3)

Although the actual communication cable 20 is a finite length line, according to the theory of the distributed constant circuit, the end of the finite length line is closed by the characteristic impedance which is one of the quadratic constants of the line. When the impedance matching is performed by using the impedance equation, the transmission equation matches the transmission equation of the infinite length line, and the handling becomes very simple.

In the present invention, attention is paid to this point, and in the comparative measurement between the first secondary voltage and the second secondary voltage in the phase detection test between the electric stations at two remote points, the laying distance is known. In addition, a communication cable for a tele-converter, in which the type and characteristics of the cable are constant, is used as a transmission line, and the transmission substation 101 uses the first secondary voltage, which is a reference for measurement, at the beginning (transmission) of the communication cable. End of the cable, the characteristic impedance 83 is connected to the end (reception end) of the cable to achieve impedance matching, so that the used line of the communication cable is treated as equivalent to an infinite length line. Can be.

The length of the transmission line, that is, the communication cable 2
The laying distance of 0 is a known variable and the communication cable 20
Is a known constant, the voltage applied to the starting end of the communication cable 20 at the transmission power station 101 is transmitted over the communication cable 20 and
The voltage attenuated and the phase rotated while appearing between the terminals of the characteristic impedance 83 connected to the end of the communication cable 20 in can be determined by applying the transmission equation of the infinite length line.

Therefore, the voltage appearing between the terminals of the characteristic impedance 83 connected to the end of the communication cable 20 at the receiving power station 102 is measured, and the first secondary voltage applied to the start end of the communication cable 20 is measured from this voltage. Can be calculated and calculated, and the second of the power receiving station 102 measured with reference to the phase of the voltage appearing at the end of the communication cable 20 of the power receiving station 102.
Is corrected by calculation to the phase difference of the secondary voltage of the communication cable 20 from the beginning to the end of the communication cable 20, so that the power receiving station 102 with respect to the first secondary voltage of the power transmitting station 101 The phase difference of the second secondary voltage can be obtained.

Further, the phase difference between the first secondary voltage of the power transmission station 101 and the second secondary voltage of the power receiving station 102 with respect to the first secondary voltage, obtained by the correction calculation,
From the measured value of the second secondary voltage of the receiving power station 102 and the first secondary voltage of the transmitting power station 101,
02 can be obtained by vector calculation with respect to the second secondary voltage.

Next, the above will be specifically described. The transmission equation of the infinite line is arranged based on the above equations (1) and (2). Here, the communication cable 20 has a standard value of a rated working voltage, and it is impossible to directly apply a first secondary voltage (63.5 V or 110 V) exceeding the rated working voltage. It is assumed that the first secondary voltage of 103 is reduced to 1 / k by the step-down means (auxiliary instrument transformer or voltage divider) 86 and applied to the start end of the communication cable 20.

X: length of transmission line (communication cable) V ₁ : first secondary voltage of instrument transformer at transmission substation k: transformation ratio of auxiliary instrument transformer or voltage dividing ratio of voltage divider V ₁ / K: applied voltage at the beginning of the transmission line (communication cable) V _x : measured voltage at the end of the transmission line (communication cable) V ₂ : measured value of the second secondary voltage of the instrument transformer at the receiving power station Φ _1x : rotation phase angle of V _x with respect to V ₁ / k Φ _x2 : measured value of phase difference of V ₂ with respect to V _x Φ ₁₂ : phase difference of V ₂ with respect to V ₁ V ₁₂ : difference voltage α between V ₁ and V ₂ : Attenuation constant of transmission line (communication cable) β: Phase constant of transmission line (communication cable) Equation (3) for calculating attenuation of voltage amplitude and phase rotation on communication cable 20 expressed by the following equation (4) Is obtained.

[0117]

(Equation 4)

The phase difference and the difference voltage between the first secondary voltage at the power transmitting station 101 and the second secondary voltage at the power receiving station 102 are expressed by the following equation (4).

[0119]

(Equation 5)

From the above equations (3) and (4),
Equation (5) is obtained.

[0121]

(Equation 6)

When the first secondary voltage V ₁ of the transmission power station 101 is transmitted to the power receiving power station 102 by using the communication cable 20 of the laying distance x as the transmission line, the following equation (5) is used.
The measured value V _x in the power receiving substation 102 of the transmission voltage, the second measured also in the power receiving electric station 102
Measurement of the first secondary voltage V _{1 at} the remote transmission power station 101 at the power receiving power station 102 from the measured secondary voltage V ₂ and the measured phase difference Φ _x2 between V _x and V ₂ , And the difference voltage V ₁₂ and the phase difference Φ between the first secondary voltage of the power transmission station 101 and the second secondary voltage of the power receiving station 102.
_Twelve measurements can be made.

The phase detection test apparatus of the present invention has a configuration in which a mode in which correction is performed by the above-described correction means and a mode in which correction is not performed (or a mode in which simpler correction is performed) can be selected. The transmission of the phase selection command signal and the transmission of the first secondary voltage can be performed by the communication cable 2.
It is also possible to adopt a configuration in which a mode that is shared by the same line 0 and a mode that uses different lines can be selected.

FIG. 5 is a block diagram showing a configuration example of the measuring means 90 in the present invention. As shown in the figure, the measuring means 90 includes a microprocessor (CPU) 91 and an input unit 9 for inputting a second secondary voltage of the instrument transformer 104.
2, a phase selection circuit 93 for selecting the phase of the second secondary voltage input to the input unit 92, and a phase selection control circuit 94 for controlling the phase designation data setting device 5 of the phase selection command means 82. . The phase selection circuit 93 has a circuit having the same configuration as that of the switch circuit 88.

The microprocessor 91 has a phase selection circuit 9
3 and the first secondary voltage of the phase specified by the phase selection command means 82 by the operation of the phase selection control circuit 94, ie, the measuring means 90 via the communication cable 20. The first secondary voltage transmitted to the first and second secondary voltages is synchronously input, and the six types of the second secondary voltage and the six types of the first secondary voltage are preset. Phase selection circuit 93 and phase selection control circuit 9 so that a predetermined combination is obtained.
4 is controlled.

The microprocessor 91 has input means 105 for inputting predetermined information and display means 106.
And the printer 107 are connected. Input means 10
Reference numeral 5 denotes, for example, an operation panel on which keys and switches are arranged. For example, information on a communication cable length x, an attenuation constant α, a phase constant β, a transformation ratio k, etc., and various conditions regarding operation of the device (For example, setting of various modes, measurement items, number of measurements, display conditions, printing conditions), various conditions related to the phase detection test (for example, information on the electric station to be tested, cable laying distance, test date and time, test environment conditions), etc. Can be entered manually or automatically. At the time of the phase detection test, necessary information among them is input in advance. The input information is stored in a memory built in the microprocessor 91.

The display means 106 is constituted by, for example, an LCD (liquid crystal display element) and its driving circuit.
As a result of the determination, it is possible to display information relating to a test and information relating to the present apparatus, such as a pattern in the case where there is an incorrect connection, an operation state of the apparatus, and the like. The display means 106 is not limited to one using an LCD, and may be, for example, a CRT or the like.

The printer 107 can print out the content displayed on the display means 106 and the result of the tally.

The first secondary voltage V _x transmitted to the receiving end (termination) of the communication cable 20 and appearing between the terminals of the characteristic impedance 83 passes through the low-pass filter 95 and is amplified by the amplifier 96. Thereafter, the signal passes through a low-pass filter 97, is converted into a digital signal by an A / D converter 981, and is input to the microprocessor 91. Note that the first secondary voltage Vx is _supplied to the low-pass filters 95 and 97.
, The superimposed phase selection command signal (modulated wave or carrier wave) is removed.

On the other hand, the second secondary voltage V ₂ is input from the input section 92 to the phase selection circuit 93, and a predetermined phase is selected by the phase selection circuit 93 and output. The second secondary voltage V ₂ output from the phase selection circuit 93 is amplified by the amplifier 99, converted to a digital signal by the A / D converter 983, and input to the microprocessor 91.

The first secondary voltage V _x passed through the low-pass filter 97 and the second secondary voltage V _x passed through the amplifier 99
₂ is also input to the A / D converter 982, and the phase difference Φ _x2 obtained _therefrom is converted into a digital signal and input to the microprocessor 91.

The arithmetic unit of the microprocessor 91 is programmed to perform the operation according to the above equation (5) (or the above equation (4)), and each of the input values (V _x , V ₂ ,
Φ _x2 ) is substituted into the above equation (5) (or the above equation (4)) and subjected to a correction operation to obtain the first secondary voltage V ₁ , the difference voltage V ₁₂ and the phase difference Φ ₁₂ . .

The first secondary voltage V ₁ , the second secondary voltage V ₂ , the difference voltage V ₁₂ and the phase difference Φ ₁₂ are
All the predetermined combinations of the six types of phases on one side and the six types of phases on the power receiving substation 102 side are obtained and totaled. The obtained individual data and the tabulated data are displayed on the display means 106 and output to the printer 105 as necessary.

Next, the phase detection test apparatus of the present invention will be described in more detail based on specific examples.

Example 1 A phase test was conducted by using the phase test apparatus 100 of the present invention described above, using existing substations operated as a real system.

[0136] Transmission substation 101 were subjected to this test, a transmission line TL _A between receiving substation 102, TL _B, connection TL _C is a normal connection state shown in FIG. 6, the power transmission substation 10
The power transmission terminal of each power transmission line installed in No. 1 was tested with all three phases connected (power transmission enabled state). The nominal laying distance of the communication cable installed between the electric stations 101 and 102 was 11.1 km.

The values of the attenuation constant α, the phase constant β, and the transformation ratio k are stored in advance in a memory built in the microprocessor 91 of the phase detection test apparatus 100. The length x = 11.1 km of the used line of the communication cable was input from the input means 105.

In this state, the phase detector 100 is operated,
By the measuring means 90, the first secondary voltage of the instrument transformer 103 of the transmission power station 101, the second secondary voltage of the instrument transformer 104 of the power receiving station 102, their difference voltage and phase difference are determined. Each measurement was made, the measured data was totaled and displayed on a display means (LCD) 106, and the displayed contents were printed out by a dot printer 107.
The results are shown in Tables 1 to 5 below.

[0139] As supplementary data, the power transmission
In Table 1 and Table 2, the values (sending-side voltages) of the first secondary voltage of the instrument transformer 103 actually measured by the voltmeter in Table 1 are shown in Tables 1 and 2. Table 4 shows the values (the sending-side phase) of the first secondary voltages actually measured by the phase meter.

[0140]

[Table 1]

[0141]

[Table 2]

[0142]

[Table 3]

[0143]

[Table 4]

[0144]

[Table 5]

As shown in Tables 1 to 5, the phase voltage, the line voltage, the difference voltage, the sending-side phase and the phase difference are all normal values, and the connection between the two electric stations 101 and 102 is normal. Was confirmed to be normal.

(Embodiment 2) Next, the electric stations 101 and 102
Transmission line TL _A connecting the, TL _B, the connection of the TL _C creates connections in erroneous changed as shown in FIG. 7, was measured similar using the same test phase test device 100 as in Example 1 .
The results are shown in Tables 6 to 10 below. The supplementary data similar to the above is shown in Tables 6, 7, and 9, respectively.

[0147]

[Table 6]

[0148]

[Table 7]

[0149]

[Table 8]

[0150]

[Table 9]

[0151]

[Table 10]

As shown in Tables 6 to 10, the phase voltage, the line voltage, and the sending-side phase relating to the first secondary voltage all show normal values. A difference voltage between the 1A phase and the 1B phase of the first secondary voltage phase (the same applies hereinafter) and the 2A phase and the 2B phase of the test side phase (corresponding to the second secondary voltage phase and the same hereinafter); That is, 1A-2
A, the differential voltage between 1A-2B, 1B-2A and 1B-2B, and the phase difference between the reference side phases 1A, 1B and 1C in Table 10 and the test side phases 2A and 2B, ie 1A -2A, 1A-2B, 1B-2A, 1B-2B,
The phase difference between 1C-2A and 1C-2B was clearly abnormal, and it was confirmed that there were misconnections between the AB phases and between the BA phases between the electric stations 101 and 102.

(Embodiment 3) Next, the electric stations 101 and 102
Transmission line TL _A connecting the, TL _B, the connection of the TL _C creates connections in erroneous changed as shown in FIG. 8, was measured similar using the same test phase test device 100 as in Example 1 .
The results are shown in Tables 11 to 15 below. In addition, the supplementary data similar to the above are shown in Tables 11, 12 and 1, respectively.
It is shown in FIG.

[0154]

[Table 11]

[0155]

[Table 12]

[0156]

[Table 13]

[0157]

[Table 14]

[0158]

[Table 15]

As shown in Tables 11 to 15, the phase voltage, the line voltage, and the sending-side phase relating to the first secondary voltage all show normal values. 1B phase and 1C phase and 2B phase and 2C of test side phase
Phase difference voltage, ie, 1B-2B, 1B-2C, 1C-2
B and 1C-2C, and the phase difference between the reference side phases 1A, 1B and 1C and the test side phases 2B and 2C in Table 15, ie 1A-2B, 1A-2C,
1B-2B, 1B-2C, 1C-2B and 1C-2C
The phase difference between the two substations 101,
It was confirmed that there were misconnections between the BC phases between 102 and between the CB phases.

(Embodiment 4) Next, the electric stations 101 and 102
Transmission line TL _A connecting the, TL _B, the connection of the TL _C creates connections in erroneous changed as shown in FIG. 9, was measured similar using the same test phase test device 100 as in Example 1 .
The results are shown in Tables 16 to 20 below. In addition, the supplementary data similar to the above are shown in Tables 16, 17 and 1, respectively.
It is shown in FIG.

[0161]

[Table 16]

[0162]

[Table 17]

[0163]

[Table 18]

[0164]

[Table 19]

[0165]

[Table 20]

As shown in Tables 16 to 20, the phase voltage, the line voltage, and the sending-side phase relating to the first secondary voltage all show normal values. 1A phase and 1C phase and 2A phase and 2C of test side phase
Phase difference voltage, ie, 1A-2A, 1A-2C, 1C-2
A and 1C-2C differential voltage, and the phase difference between the reference side phase 1A phase, 1B phase and 1C phase and the test side phase 2A phase and 2C phase in Table 20, that is, 1A-2A, 1A-2C,
1B-2A, 1B-2C, 1C-2A and 1C-2C
The phase difference between the two substations 101,
It was confirmed that there were misconnections between the AC phases and between the CA phases 102.

(Embodiment 5) Next, the electric stations 101 and 102
Transmission line TL _A connecting the, TL _B, the connection of TL _C 10
And the same measurement was performed using the same phase detection test apparatus 100 as in Example 1. The results are shown in Tables 21 to 25 below. In addition, supplementary data similar to the above are shown in Table 21, Table 22, and Table 24, respectively.

[0168]

[Table 21]

[0169]

[Table 22]

[0170]

[Table 23]

[0171]

[Table 24]

[0172]

[Table 25]

As shown in Tables 21 to 25, the phase voltage, the line voltage, and the sending-side phase related to the first secondary voltage all show normal values. 1A phase, 1B phase and 1C phase and 2A phase of test side phase,
The difference voltage between the 2B phase and the 2C phase, that is, 1A-2A, 1A
-2B, 1B-2B, 1B-2C, 1C-2A and 1
C-2C differential voltage and 1A of reference side phase in Table 25
Phase, 1B phase and 1C phase and the phase difference between the test side phase 2A phase, 2B phase and 2C phase, that is, 1A-2A, 1A-2B,
1A-2C, 1B-2A, 1B-2B, 1B-2C, 1
For all phase differences of C-2A, 1C-2B, 1C-2C,
There is a clear abnormality, and A between the two substations 101 and 102
It was confirmed that there were misconnections between the B phases, between the BC phases, and between the CA phases.

(Embodiment 6) Next, the electric stations 101 and 102
Transmission line TL _A connecting the, TL _B, the connection of TL _C 11
And the same measurement was performed using the same phase detection test apparatus 100 as in Example 1. The results are shown in Tables 26 to 30 below. The supplementary data similar to the above is shown in Tables 26, 27 and 29, respectively.

[0175]

[Table 26]

[0176]

[Table 27]

[0177]

[Table 28]

[0178]

[Table 29]

[0179]

[Table 30]

As shown in Tables 26 to 30, the phase voltage, the line voltage and the sending-side phase relating to the first secondary voltage all show normal values. 1A phase, 1B phase and 1C phase and 2A phase of test side phase,
The difference voltage between the 2B phase and the 2C phase, that is, 1A-2A, 1A
-2C, 1B-2A, 1B-2B, 1C-2B and 1
C-2C differential voltage and 1A of reference side phase in Table 30
Phase, 1B phase and 1C phase and the phase difference between the test side phase 2A phase, 2B phase and 2C phase, that is, 1A-2A, 1A-2B,
1A-2C, 1B-2A, 1B-2B, 1B-2C, 1
For all phase differences of C-2A, 1C-2B, 1C-2C,
There is a clear abnormality, and A between the two substations 101 and 102
It was confirmed that there were misconnections between the C phases, between the BA phases, and between the CB phases.

In the above Examples 2 to 6, it is also possible to specify the erroneous connection patterns shown in FIGS. 7 to 11 from combinations of data indicating abnormal values (matrix shown in the table).

(Embodiment 7) The above-described Embodiments 1 to 6 except that the transmission power station 101 was changed to a closer place (x = 4.1 km).
A phase detection test was performed in the same manner as in the above, and the same results were obtained in all cases.

(Embodiment 8) The above-mentioned Embodiments 1 to 1 were carried out except that the power transmission substation 101 was changed to a farther place (x = 15.2 km).
A phase detection test was performed in the same manner as in Example 6, and the same results were obtained in all cases.

[Discussion] The following was confirmed by the above test.

1. The transmission of the phase selection information between the two electric stations and the function operation of the phase selection based on the information were properly performed.

[0186] 2. By the action of the correcting means, an appropriate measurement value is obtained in consideration of the voltage attenuation and the phase rotation in the transmission of the first secondary voltage, and without digitizing the secondary voltage at each of the two remote electric stations. , It was possible to measure at the same time in real time at the same place with the analog amount.

[0187] 3. Automatic processing and tabulation of measurement data became possible, making work easier and increasing the reliability of test results. As a result, the safety was significantly improved without causing a great influence (for example, a power failure) on the power system due to a measurement error or a measurement data error.

4. In the conventional phase test, the work required five man hours per power receiving substation. However, according to the present invention, the measurement and the accompanying work are easy, so the time required is less than one man hour. In this case, the work efficiency is greatly reduced to 1/5 or less of that of the prior art.

[0189] 5. Since measurement can be performed with all three phases connected on the power transmission side and the power reception side, it is troublesome and risky to switch measurement phases and the connection of measuring instruments as in the conventional phase detection test. It is no longer necessary to perform the test, and the work efficiency has been improved, and the safety of the test has been significantly improved.

As described above, the phase detection test apparatus of the present invention has been described with reference to the illustrated embodiment, but the present invention is not limited to this. For example, the transmission means, the measurement means, the identification means, the correction means, the discrimination means, and the like in the phase detection test apparatus of the present invention are not limited to the configurations of the above-described embodiments, but have any configuration that exhibits the same function. Can be replaced by

In the present invention, the measurement items include some of the items (for example, the first secondary voltage and the second secondary voltage, their difference voltage and phase difference) Either one of them) may be added, and other measurement items and inspection items may be added.

[0192]

As described above, according to the phase detection test apparatus of the present invention, the first secondary voltage and the second secondary voltage can be directly compared at one place, and the conventional measurement can be performed. Measurement of difference voltage and phase difference, especially quantitative measurement,
Moreover, since the measurement data can be automatically processed and tabulated, the reliability of the test results is high, and the measurement operation and the like are extremely simple.
In particular, when the phase of the first secondary voltage to be transmitted is identified, or when the correction is performed in consideration of the change in the voltage and phase accompanying the transmission of the first secondary voltage, the reliability of the measurement data is low. And more appropriate test results are obtained. As a result, the safety is remarkably improved without greatly affecting the power system, and stable power supply can be achieved.

Further, according to the present invention, since the test can be performed in a state where all phases are connected to the power transmission system, measurement which requires a great deal of labor and time and is dangerous, such as a conventional phase detection test, is possible. The phase switching and associated work are not required, and the work efficiency and safety during the phase detection test are dramatically improved.

Further, since the phase detection test apparatus of the present invention has a simple configuration, there are few failures, maintenance is easy, and the production cost is low. Further, in the present invention, when the transmission of the first secondary voltage and the transmission of the information for identifying the phase are performed by one line of the communication cable, the line can be effectively used.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing an embodiment of a phase detection test apparatus according to the present invention.

FIG. 2 is a block diagram showing a configuration of an identification unit in the phase detection test apparatus shown in FIG.

FIG. 3 is a waveform chart of an output signal in each section of the identification means shown in FIG. 2;

FIG. 4 is a block diagram showing a configuration of a transmission unit in the phase detection test apparatus shown in FIG.

FIG. 5 is a block diagram showing a configuration of a measuring means in the phase detection test apparatus shown in FIG.

FIG. 6 is a circuit diagram schematically illustrating a connection state (normal) of a transmission line between electric stations.

FIG. 7 is a simplified circuit configuration diagram showing a connection state (abnormality) of a transmission line between electric stations.

FIG. 8 is a circuit diagram schematically illustrating a connection state (abnormality) of a transmission line between electric stations.

FIG. 9 is a circuit diagram schematically illustrating a connection state (abnormality) of a transmission line between electric stations.

FIG. 10: Connection state of transmission lines between electric stations (abnormal)
FIG. 2 is a simplified circuit configuration diagram showing FIG.

FIG. 11 is a connection state of a transmission line between electric stations (abnormal).
FIG. 2 is a simplified circuit configuration diagram showing FIG.

[Explanation of symbols]

 Reference Signs List 1 clock pulse generator 2 to 4 terminal 5 phase designation data setting device 6 terminal 7 AND gate 8 terminal 9 preset counter 10 terminal 11 flip-flop 12 terminal 13 amplifier 14 carrier wave transmitter 15 terminal 16 modulator 17 terminal 18 amplifier 19 high band Pass filter 20 Communication cable 21 Bandpass filter 22 Amplifier 23 Demodulator 24 Amplifier 25 Terminal 26 Clock pulse generator 27 Terminal 28 AND gate 29 Terminal 30 Up counter 31 Terminal 32 Comparator 33 Data memory 34, 35 terminal 36 Flip-flop 37 Terminal 38 delay element 39 AND gate 40 terminal 41 flip-flop 42 terminal 43 delay element 44 AND gate 45 terminal 46 flip-flop 47 terminal 48 delay element 49 AND gate 0 terminal 51 flip-flop 52 terminal 53 delay element 54 AND gate 55 terminal 56 flip-flop 57 terminal 58 delay element 59 AND gate 60 terminal 61 flip-flop 62 terminal 63 logic circuit 64 to 71 terminal 72 pulse timer 73 terminal 80 identification means 81 Phase selection means 82 Phase selection command means 83 Characteristic impedance 85 Transmission means 86 Step-down means 87 Input unit 88 Switch circuit 89 Low-pass filter 90 Measurement means 91 Microprocessor 92 Input unit 93 Phase selection circuit 94 Phase selection control circuit 95 Low-pass Filter 96 Amplifier 97 Low-pass filter 981 to 983 A / D converter 99 Amplifier 100 Phase detection test device 101 Power transmission station 102 Power reception station 103, 104 Transformer for instrument 105 Input means 10 Display means 107 printer

────────────────────────────────────────────────── ─── Continuing on the front page (72) Koji Tamoto, Inventor Kansai Electric Power Co., Inc. 3-2-2 Nakanoshima, Kita-ku, Osaka-shi, Osaka (72) Inventor Masato Nagai 3-chome, Nakanoshima, Kita-ku, Osaka, Osaka No. 22 Kansai Electric Power Co., Inc. (72) Inventor Seiichi Murano 3-22 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Within Kansai Electric Power Co., Ltd. (72) Inventor Takeichi Onodera 1-26 Higashi-Rokugo, Ota-ku, Tokyo No. 8 Inside Keihin Denso Co., Ltd. (72) Inventor Masayuki Aiba 1-26-8 Higashirokugo, Ota-ku, Tokyo Inside 72nd Keihin Denso Co., Ltd. (72) Inventor Yuhei Chiyama Ota-ku, Tokyo 1-26-8 Higashi-rokugo Inside Keihin Denki Sokki Co., Ltd. (56) References JP-A-60-253881 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) G01R 29 / 18 G01R 31/02 H02J 3/00

Claims (11)

(57) [Claims] 1. A multi-phase alternating current between a transmission power station and a receiving power station located at remote points from each other, wherein a first secondary voltage of the polyphase alternating current in an instrument transformer installed in the transmission power station and the power reception. A phase detection test device that performs a phase detection test based on a polyphase alternating current second secondary voltage in an instrument transformer installed in an electric station, wherein the first secondary voltage is transmitted to the power transmission station. And transmission means for transmitting to each of the power receiving stations for each phase using a communication cable having a known electrical characteristic connecting the power receiving stations, and the first secondary transmitted at the power receiving station. Measuring means for measuring a voltage and the second secondary voltage corresponding thereto; and correcting means for correcting a change in voltage and phase due to electrical characteristics of the communication cable, wherein the correcting means comprises: The above-mentioned power reception of the line using the communication cable By terminating the receiving end in the air place with a characteristic impedance, the used line is treated equivalent to an infinite length line, and the voltage attenuation and phase rotation on the communication cable using the length of the communication cable as a variable. Using a calculation formula for calculating the following equation, the first secondary voltage at the receiving end is corrected in consideration of the amount of voltage attenuation in which the first secondary voltage attenuates according to the length of the communication cable. Performing a first secondary voltage applied to a transmitting end of the transmission line at the power transmission substation of the working line, and measuring the first secondary voltage transmitted to the receiving end as a phase reference. The phase value of the second secondary voltage at the receiving power station is corrected in consideration of the rotation of the phase of the voltage generated by the first secondary voltage according to the length of the communication cable, and the correction is performed at the transmitting end. The receiving power for a first secondary voltage A phase detection test apparatus for determining a phase difference of a second secondary voltage of an air place. 2. The method according to claim 1, wherein the correcting unit further includes: a first secondary voltage at the transmitting end or the receiving end;
From the second secondary voltage measured at the receiving substation, a first secondary voltage of the transmitting substation and a second secondary voltage of the receiving substation are calculated.
2. The phase detection test device according to claim 1, wherein a difference voltage from the secondary voltage is obtained. 3. The detection method according to claim 1, wherein the measuring unit is configured to determine a difference voltage and / or a phase difference between the first secondary voltage and the second secondary voltage. Phase test equipment. 4. The phase detection test apparatus according to claim 1, wherein said transmission means sequentially transmits a voltage of each phase and a line voltage of the polyphase alternating current in a predetermined order. 5. The phase detection test apparatus according to claim 1, wherein the transmission unit transmits the first secondary voltage using one line of the communication cable. 6. The transmission means has a step-down means, and the step-down means transmits the first secondary voltage after stepping down the voltage so as to match a rated working voltage of the communication cable. A phase detection test apparatus according to item 1. 7. The phase detection test device according to claim 6, wherein the step-down unit is an insulation type transformer. 8. An identification means for identifying a phase of a first secondary voltage transmitted from the transmission power station and a phase of a first secondary voltage transmitted at the power reception power station. 8. The phase detection test apparatus according to any one of 7. 9. The phase selecting means for selecting a phase of the first secondary voltage to be transmitted or a combination thereof,
Phase selection command means for transmitting a phase selection command signal to the phase selection means, wherein the phase selection means is configured to select the phase or a combination thereof in accordance with the input command signal. A phase detector according to claim 8. 10. The phase detection test apparatus according to claim 9, wherein the transmission of the command signal to the phase selection means and the transmission of the first secondary voltage to the power receiving substation are performed on the same line. . 11. The phase detection test apparatus according to claim 10, further comprising a discriminating means for discriminating between the command signal and the first secondary voltage.