JPH0311000B2 - - Google Patents

Description

[Detailed description of the invention]

[Technical Field of the Invention] The present invention relates to a system for monitoring and controlling various traffic signal lights. [Prior Art] For example, monitoring and controlling traffic signal lights for railways involves lighting up each of the blue, yellow, and red signal lights individually using an AC power source through relay contacts, as well as connecting a current transformer to the signal light circuit. It is common practice to insert a relay and detect the breakage of a signal light according to its output.Since the relay contacts turn on and off depending on the out-of-synchronization with the power supply, there is a possibility that the contacts may be damaged by inrush current. In addition, there is no method for detecting disconnection of the signal light, resulting in insufficient reliability and fail-safety. In addition, originally, the brightness of the signal light should be increased or decreased depending on the surrounding brightness, but a method of switching the taps of the power transformer has been proposed, but since the control of this is complicated, most In this case, dimming control is not performed, and the brightness becomes higher than necessary at night, making it unsuitable for visual inspection, and also has disadvantages such as consuming excess power and becoming uneconomical. [Summary of the Invention] The present invention has the purpose of fundamentally solving the above drawbacks of the conventional technology, and detects the waveform change point of the AC power source for signal lights, and applies the AC power to the signal lights based on the detected power. In addition to controlling the lighting and dimming of the signal lamp, the system applies AC power to the signal lamp for a short period of time based on the detection power of the waveform change point, and detects the current flowing to the signal lamp at this time. To provide an extremely effective method for monitoring and controlling signal lights, which determines whether there is an abnormality or not, and when it is determined that there is an abnormality, forcibly operates the circuit breaker of the signal light circuit, and also confirms this. It is. [Example] Hereinafter, details of the present invention will be explained with reference to figures showing examples. FIG. 1 is a block diagram showing the configuration. A control unit CNT is provided, each of which is composed of a plurality of control circuits including a processor such as a microprocessor and a memory. and DR are given,
A signal LD is given as a dimming condition signal,
As a control output based on these, gate pulse P _G ,
P _Y and _PR are sent from the control unit CNT. On the other hand, there are signal lights L _G , L _Y , L _R that are lit by an AC power source AC of 50 Hz, 30 V, etc., and switches SW G , SW Y using switching elements such as bidirectional thyristors are connected in series with each of these signal lights L _G , L _Y , L R . , SW _R are inserted into each gate, and each of these gate inputs G
The gate pulses P _G , P _Y , P _R from the control unit CNT are
are given correspondingly to each individual, and gate pulses P _G ,
Since either P _Y or _PR occurs selectively, the corresponding switch is turned on, and the corresponding signal light is accordingly turned on. In addition, signal light L _G via switch SW _G ~ SW _R
~L During the common return path of _R , a current transformer is placed in series with these.
CT and circuit breaker CB are inserted, current transformer
The current detection force of the CT is given to the control unit CNT, and when a serious abnormality is judged based on this, the control unit CNT sends out a gate pulse P _E to forcibly operate the circuit breaker CB. AC power supply
For the purpose of cutting off the application of AC, a resistor Rov is installed in parallel with the signal lights L _G ~ L _R to pass the cutoff current, and in series with this is a switch SW _G ~ SW _R that is turned on by the gate pulse P _E. A switch SW _E similar to the above is inserted, and when the circuit breaker CB is operated by these, the auxiliary contact CB of this turns on,
The control unit CNT checks the operation of the circuit breaker CB, and if it does not operate, restores the relay FLR and turns off its contact FLR ₁ to disconnect the AC power supply AC. In addition, in order to detect the waveform change point of AC power source AC, a phase detector using a zero cross comparator etc.
A PSD is provided, and the control unit CNT determines the sending time and pulse width of the gate pulses P _G to P _R based on the detection power of the PSD.
The time and period of applying AC power to L _G to L _R are set, and their lighting and dimming are controlled. However, in addition to the lighting control described above, the control unit CNT
is periodically lit only for short periods of time when it is impossible to see it.
The alternating current power supply AC is sequentially applied to the signal lights L _G ~L _R , and the current flowing at this time is detected according to the output of the current transformer CT, and thereby the signal lights L _G ~
It is designed to determine a break in L _R or a short circuit involving switches SW _G to SW _R. If a short circuit is determined based on this result, cutoff control is performed as described above. In addition, if only the signal light L _G or L _Y is broken,
When L _G should be lit, L _Y is lit, and when L _Y should be lit, L _R is lit, and the lighting control is performed sequentially to the safe side, and no cut-off control is performed. FIG. 2 is a timing chart showing the waveforms of each part in FIG.
The control unit CNT internally repeats setting and resetting the 1/2 cycle flag c, and counts the cycle T according to the change in this, and calculates the cycle T determined by the frequency of the AC power source AC. For example, every time nT, which corresponds to 200 msec, is counted sequentially, check gate pulses d to f with a pulse width of _t1 are sequentially sent out during the period in which the 1/2 cycle flag c is set. In other cases, a gate pulse with a pulse width of t ₂ or t ₃ is sent out according to the signals HR, DR, and LD.
When the count value reaches 3nT, the count value is cleared and counting is restarted, and the same control is repeated. In addition, since the pulse width _t1 of the check gate pulses d to f is set to approximately 1/4 or less of T/2, it is impossible to visually check the lighting status of the signal lights L _G to L _R. It will be a short period of time. In addition, in Fig. 2, the signal lamp L _G is lit first, and then the signal lamp L _Y is turned on by dimming control, but the gate pulse d changes in synchronization with the zero cross point of the AC power supply a. At the same time, the gate pulse e has a pulse width t ₃ determined according to the amount of light attenuation, and the trailing edge time is determined in synchronization with the zero cross point of the AC power supply a. shall not occur, and switch SW _G ~ _{SW R}
We are trying to protect the In addition, in order to obtain high reliability and fail-safety, the control unit CNT extracts the majority decision of the same logic value from data from multiple control circuits.
Measures such as using data with the same logical value that is the most common are adopted, and if a majority vote cannot be obtained, the relay FLR is restored and the contact FLR ₁ inserted in series with the circuit breaker CB is turned off. And signal light L _G ~
All L and _R lights are turned off. Incidentally, the lighting control in response to the signals HR and DR is performed according to the logical value relationships shown in the table below.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, the lighting control of the signal lamp is synchronized with the AC power supply and the lighting status is checked, so that the inrush current is reduced, and the lighting control is performed to the safe side in response to the breakage. In addition, in the event of a serious abnormality, the AC power supply is forcibly cut off, and dimming control is also possible, achieving high reliability and fail-safe properties, making it a remarkable effect in controlling various signal lights. exhibits.

[Brief explanation of the drawing]

The figures show an embodiment of the present invention; FIG. 1 is a block diagram, FIG. 2 is a timing chart showing waveforms of each part in FIG. It is a flowchart. CNT...Control unit, SW _G ~ SW _E ...Switch,
L _G ~L _R ... Signal light, CT... Current transformer, CB... Circuit breaker, cb... Auxiliary contact, PSD... Phase detector,
FLR...Relay, FLR ₁ ...Contact, AC...Alternating current power supply, HR, DR...Lighting condition signal, LD...Dimming condition signal.

Claims (1)

[Claims] 1. Control unit CNT and a plurality of signal lights L _G , L _Y , L _R
, current transformer CT, circuit breaker CB, phase detector PSD
_{A signal} lamp monitoring and _control system having If it is supplied, the lighting state is visible, but if it is less than that time, the lighting state is not visible.The current transformer CT detects the current flowing in the circuit, and the circuit breaker CB operates. The control unit CNT switches the AC power supply to the signal lights L _G , L Y , based on the detection output of the phase detector PSD in accordance with the lighting signal conditions HR, DR and the dimming condition signal _LD . In addition to controlling the lighting and dimming of the signal light by controlling the point and time applied to L and _R , the phase detector PSD
Based on the detection output of A signal light monitoring and control system characterized by forcibly operating the circuit breaker and confirming the operation of the circuit breaker.