JPS6062247A - Slave station answer transmitter receiver of distribution line carrier control system - Google Patents

Abstract

PURPOSE:To perform stable transmission while reducing variation in signal current transmission ratio equivalently by transmitting an answer signal from the answer transmitter of a slave station to be controlled to the receiver of a control station by utilizing frequency components which are properly distant from each other. CONSTITUTION:The answer signal is received through a current transformer 7 and an auxiliary transformer 10 coupled with a high voltage circuit 9 and inputted to a current voltage converter. The output of a transformer 11 is inputted to an LC filter 12 having a passing frequency f1 and an LC filter 13 having a passing frequency f2. The outputs of the filters 12 and 13 are amplified 14 and 15 and filtered through mechanical filters 16 and 17 having passing frequencies f1 and f2. Their outputs are amplified 18 and 19 and detected 20 and 21. The output waveforms of the detectors 20 and 21 are summed and amplified 22 to obtain an equivalently large answer signal by summing the components of frequencies f1 and f2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a slave station response transmitting/receiving device in a distribution line carrier control system.

FIG. 1 is a general conceptual diagram of a distribution line transmission control system. A control command (for example, consisting of the address of the controlled slave station, type of control, etc.) for controlling the high voltage automatic switch 3 is issued from the power distribution command console 1 of the control station (power generation/substation) to the controlled slave station 2. Then, the control command is injected into the signal injection device (Rinnor control) 4, a high voltage distribution line (bus bar) 5K, and a command signal in which the control command is encoded. This command signal is transmitted to the controlled element 82 via the pole transformer 6. The controlled slave station 2 decodes the command contents of the received command signal, determines whether its own station has been called, whether the control command is input or released, etc., and if its own station has been called, controls it. Executes commands and sends response signals. The response signal is inputted to the response signal receiving device 8 via the current transformer 7. The response signal reception wave (, thys) separates only the frequency of the response signal and sends it to the power distribution control console I.

In such a distribution line transport control system, the receiving point (
The signal current transmission ratio, expressed as the ratio of the received signal current at a substation, etc.) to the transmitted signal current at a signal injection point (slave station), varies greatly depending on the condition of the distribution line and the signal frequency. For example, the second
Figure 1l-i Relationship between line span length and signal current transmission ratio in a distribution line at two different frequencies f1. An example of measurement for f2 is shown in Figure 3, which shows the frequency fI at a specific location.
, f2 shows an example of a time change in the signal current transmission ratio.

As is clear from Figure 2, the signal current transmission ratio changes significantly depending on the line span length, that is, the impedance of the distribution line, and as shown in Figure 3, the signal current transmission ratio changes as the load on the distribution line changes with time. changes. moreover,
It can be seen that the signal current transmission ratio changes not only depending on the condition of the power distribution line but also depending on the signal frequency used.

In conventional distribution line carrier control systems, signals are transmitted using a single carrier frequency, but as mentioned above, the signal current transmission ratio fluctuates significantly depending on the condition of the distribution line, so it is difficult to maintain a sufficient signal current transmission ratio. However, there are cases in which the system is not reliable, and there is a drawback that the reliability of the system is lowered due to transmission errors.

An object of the present invention is to provide a slave station response transmitting/receiving device that eliminates such conventional drawbacks.

In order to achieve this object, the present invention is directed to FIGS.
As shown in the figure, two frequencies f+
, :b are complementary to each other, such that when one becomes low, the other becomes high, and this relationship is utilized.

That is, the present invention provides a distribution line transportation control system that includes:
The controlled slave station response transmitter t is configured to simultaneously transmit signal currents of two frequencies intermittently according to the same signal code, and the receiving device of the control station of the power generation/substation etc. The system is characterized in that a slave station response is significantly detected by analog addition or logical sum of the signals detected and demodulated from the signal received on the secondary side of the current transformer coupled to the line.

The principles and embodiments of the present invention will be explained in detail below with reference to the drawings.

The distribution line carrier control system is shown in the conceptual diagram of FIG. 1, and the present invention is characterized in that the response transmitter in the controlled slave station 2 includes two frequency components in the response signal. Therefore, the answer transmitter of the controlled slave station 2 includes two frequency components as an answer signal by turning on and off the commercial current waveform limited by the current limiting resistor at appropriate intervals as shown in FIG. Constructed so that it can be cut. Figure 4 shows a current waveform with a commercial frequency of 60 Hz and an electrical angle of 442-5 Hz.
FIG. 5 shows an example of a waveform obtained as a result of repeating off and on cycles at intervals of 80 degrees, and the results of frequency analysis of this waveform are shown in FIG. As can be seen from FIG. 5, 442.
There is no frequency component of 5 Hz at all, and from this 60 H
z lower 382.5Hz and 60Hz higher 502.5
Two frequencies of Hz are output. These two frequencies are used as response signal frequencies.

FIG. 6 shows an example of a circuit for obtaining the waveform shown in FIG. A series circuit consisting of a current-limiting resistor R and a transistor Q is connected between the other pair of terminals of the same circuit, and a diode D5 is connected to the base of the transistor Q. Also, the pace is 4
A signal with a frequency of 42.5 Hz is applied to control the on/off of the current ID in the series circuit. The waveform of the current IA flowing on the AC side of the circuit shown in FIG. 6 is as shown in FIG.

FIG. 7 shows another example of a circuit for obtaining an external waveform as shown in FIG. 4, in which a current-limiting resistor RI%
Auxiliary resistor R2, commutation capacitor C1 main thyristor SC
This configuration uses a circuit consisting of R and an auxiliary Zyrister 5CR2. A trigger pulse P shown in FIG. 8 is applied to the control electrode of the main thyristor SCR, and a trigger pulse P1 is applied to the control electrode of the auxiliary thyristor 5CR2.
By applying the signal P2 at an interval corresponding to 1800 electrical angles of 442.5 Hz, the waveform of the current ■□ becomes as shown in FIG.

The circuit shown in FIG. 7 is more practical than the circuit shown in FIG. 6 in terms of product reliability and production cost.

The two frequencies must be selected so that they are less affected by noise components f≧. FIG. 9 shows an example of frequency component analysis results of high voltage distribution line current. As is clear from the figure, the noise component includes many harmonic components of the commercial frequency (60 Hz), and among these, relatively low-order odd harmonic components are large. Therefore, considering this noise component, it is better to select a relatively high frequency, but on the other hand, as the frequency increases, the signal current transmission ratio generally decreases, and the variation in the signal current transmission ratio also increases, which is not preferable.

Therefore, a certain range exists as the optimal frequency for the response signal frequency, and as a selection criterion, the range between the odd harmonics and the even harmonics is divided into three, and the frequency at the trough of the even harmonics is 60 Hz.
In the case of , the hundred is 20 Hz, and even harmonics ±2
The most desirable answer signal frequency is around 0 Hz.

Specifically, since a commercially available mechanical filter is used in the response receiving device, a mechanical filter with a frequency close to this is selected. For example, 380Hz as frequency f1
When selecting a frequency near 500 Hz as Xf2, frequency 11 should be 382.5 Hz, frequency J'2 k502.
Select 5 Hz.

The slave station response signal has two carrier frequencies f1 and f as described above.
2 are transmitted intermittently according to the same data series request. That is, the denotal serial code is transmitted by sending f+ and f2 at the "pa mark" of the denotal code, and not sending fl and f2 at the "wave mark".

FIG. 10 is a diagram showing an example of a response signal receiving device according to the present invention, and FIG. 11 is a diagram showing waveforms of each part. The response signal is received via a current transformer 7 and an auxiliary current transformer 10 coupled to a high voltage line 9 and is input to a current-voltage converter 11 .

The output of the current-voltage converter 11 has a first frequency f+=382
．． The signal is input to the LC filter 12 that passes 5 Hz, and the LC filter 13 that passes the second frequency f2=502.5 Hz f. As shown in the waveform (A) of FIG. 11, the output of the current-voltage converter 11 has a fundamental wave (60H7,
), it also includes harmonic components, response signal components, noise, etc. The waveform (b) that passed through the LC filter 12 is 3
The 8.2.5 Hz component is the largest, but other noise components are also included. Similarly, the waveform (c) that has passed through the LC filter 13 includes a 502.5 Hz component and a noise component. The outputs of LC filters 12 and 13 are amplified by amplifiers 14 and 15, respectively, and then converted into P waves by mechanical filters 16 and 17. The mechanical filter 16 has a characteristic of passing 382.5Hz'((), and its output waveform is: (82.5Hz
, and other noise components have been removed. Similarly, the output waveform (g) of the mechanical filter 17 having an F-wave frequency at 502.5 Hz has only a 502.5 Hz component. These output waveforms (H) and (H) are amplified by amplifiers 18 and 19, and then detected by detectors 20 and 21, respectively. The output waveforms (1) and (IJ) of the detectors 20 and 21, respectively, are summed by the summing amplifier 22, and therefore at 382.5 Hz.
By adding the respective components of

As shown in Figure 2 or Figure 3, two frequencies have a mutually complementary relationship such that when the signal current transmission ratio of one frequency becomes low, the signal current transmission ratio of the other frequency increases. is used, the sum of the amplitudes (peak values) of the two frequency signals, that is, the amplitude level of the response signal waveform (nu), is relatively stable against fluctuations in the impedance of the distribution line and the load on the distribution line +Jf line, and the system This is very effective in improving reliability.

The output of the summing amplifier 22 is Konno'? The signal is compared with a reference voltage by the rake 2' and 3, and only the signal exceeding this reference voltage is outputted as a rectangular wave with a constant amplitude, and the reception relay 24 is driven. When the receiving relay 24 is driven according to the response signal in this way, the on/off signal is transmitted to the power distribution control console 1 (
(Fig. 1).

As described above in detail, the present invention transmits the response signal in the distribution line carrier control system using two appropriately separated frequency components, so that fluctuations in the signal current transmission ratio are equivalently reduced. This provides the advantage of achieving stable transmission power and greatly improving system reliability. In addition, since the signal current containing two frequency components can be constructed so that the commercial frequency current is cut by the control signal of the reference frequency (442.5 Hz in the above example), the device configuration can be realized relatively easily. can do.

[Brief explanation of the drawing]

FIG. 1 is a general conceptual diagram of a distribution line carrier control system, FIG. 2 is a diagram showing an example of the relationship between line span length and signal current transmission ratio, and FIG. 3 is a diagram showing the frequency f1. A diagram showing an example of a time change in the signal current transmission ratio of the f2 signal, FIG. 4 is a diagram showing an example of a signal transmission waveform including two frequency components according to the present invention, and FIG. 5 is a frequency analysis of the waveform in FIG. Figure 6 is a diagram showing an example of a circuit for obtaining the waveform shown in Figure 4. Figure 7 is a diagram showing another example of a circuit for obtaining the waveform shown in Figure 4. Applying voltage to the control electrode of the thyristor in Figure 7.
Fig. 9 is a diagram showing the frequency component analysis results of the high-voltage distribution line current, Fig. 10 is a block diagram showing an example of the response signal receiving device in the present invention, and Fig. 11 is the waveform of the signals of each part. It is a diagram. 1. Power distribution control console, 2.. Controlled slave station, 3.. High voltage automatic switch, 4.. Signal injection device, 5.. Bus bar,
6...Pole transformer, 7.10...Current transformer, 8...
-Answer signal receiving device, 11...Current voltage converter, 12
113...LC filter, 1.4 + 15 + 1
8 + 19...Amplifier, 16.17...Mechanical filter, 2o. Patent Applicant Kyushu Denki Seizo Co., Ltd. Agent Hisashi Hoshino Shiiwa Noboru - Figure 1 Figure 2 Figure 3 Jiken Figure 4 Figure 5 100 2C Gen 300 Kiku 0 Tsu O (I) 0700
■Luck 900 → 凯波系 8th figure J

Claims (1)

[Claims] In the WJJ carrier control system, there is a slave station response transmitter that transmits intermittent response signals according to serial codes in which two carrier frequencies with different frequencies are organized in the same time series, and a slave station response transmitter. After receiving the answer signal transmitted via the power distribution line, extracting and rectifying the two carrier frequency components included in the answer signal,
A slave station response transmitting/receiving device comprising: a response signal receiving device that significantly detects a slave station response by modifying the detected waveform of each frequency component.