CN211720255U

CN211720255U - Signal machine self-fusing circuit based on fault safety

Info

Publication number: CN211720255U
Application number: CN202020031439.1U
Authority: CN
Inventors: 俞敏; 徐成闻; 周旭东; 吕涛; 凌祝军; 周在福; 管伟新
Original assignee: Unittec Co Ltd
Current assignee: Unittec Co Ltd
Priority date: 2020-01-08
Filing date: 2020-01-08
Publication date: 2020-10-20
Anticipated expiration: 2030-01-08

Abstract

The utility model discloses a semaphore is from fusing circuit based on fail safe, including the semaphore return circuit of lighting a lamp, the semaphore is lighted a lamp the return circuit and is included fuse, solid-state relay, safety relay, solid-state relay and safety relay are used for controlling the break-make in semaphore return circuit of lighting a lamp, still include from fusing circuit, from fusing circuit is used for fusing fuse, and the semaphore is lighted when solid-state relay and/or safety relay contact inefficacy adhesion, and after receiving trigger signal from fusing circuit, fuses from fusing circuit. The utility model discloses a technical scheme, when the relay takes place the adhesion inefficacy, the condition that the semaphore was lighted always, the current loop of semaphore, and easy maintenance can initiatively cut off.

Description

Signal machine self-fusing circuit based on fault safety

Technical Field

The utility model relates to a track traffic technical field, concretely relates to semaphore drive circuit.

Background

The signal machine in the railway signal system is generally an electronic device set beside the rail, and is used for transmitting information such as vehicle running conditions, running equipment states and the like to the running personnel or the system. The signal system generates an interlocking constraint relation among the turnout, the route and the signal machine through the information transmitted by the signal machine, and improves the control and dispatching efficiency on the premise of ensuring the driving and shunting safety.

The signal machine driving circuit can control and reflect the working condition of the signal machine beside the rail, directly influences the driving safety and needs to meet the design principle of failure safety. The full electronic interlocking system adopts the electronic execution unit to drive the annunciator to replace the old relay control unit, thereby greatly reducing the use of relays and cables, avoiding the condition of mixed line/broken line fault of the relay interlocking system and improving the reliability, the availability and the maintainability.

The main control principle of a typical semaphore-driven electronic actuator is shown in fig. 1. In fig. 1, a dashed line frame is an electronic execution unit, and outside the dashed line frame, an alternating current power supply of a signal, other external interfaces, the signal and the like are mainly arranged. The system can design different numbers of signal machine driving circuits according to the number of the driving signal machines, so that only 1 path of signal machine driving circuits are listed, and the driving principle is the same.

During normal work, if the electronic execution unit receives the command of driving the signal machine through other interfaces, then control solid state relay and safety relay actuation and form the current loop: the signal is connected with a fuse from an alternating current power supply L of the signal, then is connected with a current detection circuit in series, and then is connected to the end A of the signal through a solid-state relay and a safety relay switch terminal 1/2; and from the signal B through the safety relay switch terminal 4/3 back to the ac power source N.

The current detection circuit forms two paths of signals which are respectively connected to the terminals 3 of the single-chip microcomputers A and B, and the two single-chip microcomputers can report the recovered current value to the system through other interfaces according to the working condition of the electrofluid signal machine.

This can be achieved by switching off the solid-state relay and the safety relay if the electronic execution unit receives a command to switch off the signaller. The solid-state relay is controlled by terminals 1 of the single chip microcomputer circuit A and the single chip microcomputer circuit B, a port 1 of the single chip microcomputer circuit A outputs a positive level to an end A of the solid-state relay, a port 1 of the single chip microcomputer circuit B outputs a negative level to an end K of the solid-state relay, and the solid-state relay is conducted only when the A and the B are both output. The control principle of the safety relay is the same, but the control is realized through the terminals 2 of the singlechip circuits A and B.

In order to improve the coverage rate of detection, square wave signals A and B are added, and the on-off condition of the relay is detected by respectively connecting normally closed contacts of the safety relay to terminals 4 of the single chip microcomputer circuit A and the single chip microcomputer circuit B.

If the output unit related to safety, such as an electronic execution unit relay driven by a signal machine, is stuck and fails, the situation that the signal machine is always lightened occurs. This situation can lead to safety issues that are not allowed, and a better solution is to cut off the power supply output of the semaphore.

Although the electronic execution unit can detect the occurrence of the fault at this time, there is no way to control the relay regardless of how to cut off the loop of the relay control terminal. It is therefore necessary to design a circuit that will actively shut off the current loop of the annunciator in the event of such a low probability fault condition.

SUMMERY OF THE UTILITY MODEL

The utility model aims to solve the technical problem that an semaphore is from fusing circuit is just provided based on fail safe, when the adhesion became invalid, can initiatively cut off the current loop of semaphore at the relay.

In order to solve the technical problem, the utility model adopts the following technical scheme: signal machine is from fusing circuit based on fail safe, including the signal machine return circuit of lighting a lamp, signal machine return circuit of lighting a lamp includes fuse, solid state relay, safety relay, solid state relay and safety relay are used for controlling the break-make in signal machine return circuit of lighting a lamp, still include from fusing circuit, from fusing circuit is used for fusing the fuse, and the signal machine is lighted when solid state relay and/or safety relay contact inefficacy adhesion, and after receiving trigger signal from fusing circuit, from fusing circuit fusing fuse.

Preferably, the self-fusing circuit comprises a resistor R1, a resistor R2 and a resistor R3 which are connected in series, wherein the resistor R1 and the resistor R2 are used for limiting current, and the resistor R3 is used for protecting the front end of the solid-state relay and improving interference resistance.

Preferably, the I2T parameter of the solid-state relay is more than three times greater than the fusing heat energy value parameter I2T of the fuse.

The utility model discloses a technical scheme, increase the self-fusing circuit who is used for fusing fuse in the circuit of lighting a lamp of semaphore, have following beneficial effect:

when the contacts of the solid-state relay and the safety relay are in failure and adhesion, the annunciator is lightened, and the interlocking system issues a command to trigger the self-fusing circuit to fuse the fuses by short-circuiting the alternating-current power supply L and the alternating-current power supply N.

Therefore, when the relay is stuck and fails and the annunciator is always lightened, the current loop of the annunciator can be actively cut off, and the maintenance is convenient.

The specific technical solution and the advantages of the present invention will be described in detail in the following embodiments.

Drawings

The invention will be further described with reference to the accompanying drawings and specific embodiments:

FIG. 1 is a block diagram of a semaphore drive electronic execution unit;

fig. 2 is a schematic diagram of the application of the self-fusing circuit based on the fail-safe of the present invention;

FIG. 3 is a schematic diagram of a self-fusing circuit implementation;

FIG. 4 is a schematic block diagram of current sensing;

fig. 5 is a current detection circuit diagram.

Detailed Description

The technical solutions of the embodiments of the present invention are explained and illustrated below, but the following embodiments are only preferred embodiments of the present invention, and not all embodiments. Based on the embodiments in the embodiment, other embodiments obtained by those skilled in the art without any creative work belong to the protection scope of the present invention.

The utility model relates to a semaphore electron execution circuit based on fail safe, this circuit can be according to current sampling discernment trouble, triggers the automatic cutout function that realizes external power supply from the fusing circuit through system's order.

As shown in fig. 2, the fail-safe annunciator electronic execution circuit is connected between an annunciator ac power supply and an annunciator, is controlled by an interlock system, and comprises an annunciator lighting loop and a single chip microcomputer, wherein the annunciator lighting loop comprises a fuse, a current detection circuit, a self-fusing circuit, a solid-state relay and a safety relay, the solid-state relay and the safety relay are used for controlling the on-off of the annunciator lighting loop, the current detection circuit is used for detecting the current of the annunciator lighting loop, the self-fusing circuit is used for fusing the fuse, and the single chip microcomputer receives the signal of the current detection circuit; when the contacts of the solid-state relay and/or the safety relay are failed and adhered, the annunciator is lightened, the single chip microcomputer detects current through the current detection circuit, but the interlocking system does not control the output of the relay, the single chip microcomputer judges the adhesion fault of the relay, reports the adhesion fault to the interlocking system through other interfaces, the interlocking system issues a command, the single chip microcomputer sends a control signal, and the self-fusing circuit is triggered to short-circuit and fuse the alternating-current power supply L and the alternating-current power supply N.

As shown in fig. 2, the single chip circuit a or B is connected to the port a of the self-fusing circuit through the port 5, and sends a signal to trigger the self-fusing circuit to operate, as shown by the devices in the block of fig. 3: the end A in the square box is connected with the ports 5 of the singlechip circuits A and B in the figure 2 in parallel, namely the end of the output of the optical couplers U2 and U3 in the figure 3. When the MCU1-IO1 output by the singlechip circuit A is a 3V3_ A signal or the MCU2-IO1 output by the singlechip circuit B is a 3V3_ B signal, the NMOS tube Q2 or Q3 is conducted, at the moment, the U2 or U3 is conducted, the A end of the self-fusing circuit is connected to the GND _ PSU, finally the U1 is conducted, and the fuse F1 is short-circuited at two ends through the boxes B and C.

In fig. 3, at this time, the ac power source is short-circuited through the contacts at the two ends B and C in the box of fig. 3, that is, the U1, the F1 is blown after a certain time of short circuit, and the blowing time is related to the blowing thermal energy value parameter I2T of the selected F1, where it is required to ensure that the I2T parameter of the solid-state relay U1 is several times greater than the parameter of the F1, and to avoid blowing of the U1 before the F1. As shown in FIG. 3, the circuit U1 adopts a Crydom CXE380D5 solid-state relay with the I2T parameter value of 260A²sec, and F1 uses a Littlefuse company 383 series 2A fuse with an I2T parameter value of 17.8A²sec, the difference is about 15 times, and the fuse blowing time is about 200 us-400 us when the fuse is used as a reference for actual test.

Resistors R1 and R2 in the self-fusing circuit are used for limiting current, the front end of the U1 is guaranteed to work in a normal current range, and the resistor R3 is used for protecting the front end of the solid-state relay and improving anti-interference performance.

Fig. 4 is a schematic block diagram of current detection of an ac annunciator, and ac current driven by the annunciator is sampled by a collection resistor, precisely rectified, waveform-amplified, and subjected to integral filtering, and then collected by an ADC.

As shown in fig. 5, the current detection specific implementation circuit has a two-channel current sampling resistor connected in series in the lighting circuit of the traffic signal, and taking channel a as an example, the sampling resistor is 2 power resistors with 0.27 Ω precision of 1% 1/4W. The acquisition interface is connected with four high-voltage-resistant diodes SM4007 in parallel by using bidirectional TVSSMCJ6.5CA, so that transient overvoltage of the current sampling circuit is limited, and a rear-stage operational amplifier is protected.

A precision rectifying circuit is formed by using a double operational amplifier IC SA5532D, a first-stage operational amplifier performs full-wave rectification to rectify a 50Hz sine wave into 100Hz negative half waves, a second-stage operational amplifier forms a proportional amplification and integration circuit, and the proportional amplification factor of a channel A is R358/R350 which is 10. R363/C122 forms low-pass filtering, R367 is a current discharge path, and D55 is used for overvoltage protection. The scale magnification of the channel B is R359/R352-20. R362/C123 forms low-pass filtering, R366 is a current discharge path, D54 is used for overvoltage protection, and channel A and channel B adopt differential processing on the amplification factor, so that the failure of a single channel can be detected in time.

According to the current detection circuit in the figure 5, when the current is collected by the detection circuit and the actual software does not control the output of the relay, the circuit adhesion fault is judged, and at the moment, the software triggers the self-fusing circuit to fuse the fuse, so that the signal lamp is prevented from being lighted to ensure safety.

Non-critical circuits such as the power supply of the amplifier, for example, the current detection circuit using a ± 5V power supply, are not described in detail here.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and those skilled in the art should understand that the present invention includes but is not limited to the contents described in the above specific embodiments. Any modification which does not depart from the functional and structural principles of the present invention is intended to be included within the scope of the claims.

Claims

1. Signal machine is from fusing circuit based on fail safe, including the signal machine return circuit of lighting a lamp, the signal machine return circuit of lighting a lamp includes fuse, solid state relay, safety relay, solid state relay and safety relay are used for controlling the break-make in signal machine return circuit of lighting a lamp, its characterized in that: the fuse protector further comprises a self-fusing circuit, the self-fusing circuit is used for fusing the fuse, the annunciator is lightened when the contacts of the solid-state relay and/or the safety relay are in failure and adhesion, and the fuse is fused by the self-fusing circuit after the self-fusing circuit receives the trigger signal.

2. The fail-safe based annunciator self-fusing circuit of claim 1, wherein: the self-fusing circuit comprises a resistor R1, a resistor R2 and a resistor R3 which are connected in series, wherein the resistor R1 and the resistor R2 are used for limiting current, and the resistor R3 is used for protecting the front end of the solid-state relay and improving the anti-interference performance.

3. The fail-safe based annunciator self-fusing circuit of claim 2, wherein: the I2T parameter of the solid-state relay is more than three times larger than the fusing heat energy value parameter I2T of the fuse.