Railway signal LED filament monitoring device and method

Abstract

The invention relates to the technical field of railway signal LED lamps, in particular to a railway signal LED lamp filament monitoring device and method, and the device comprises a direct-current power supply, a direct-current lighting unit and an LED lamp; the direct current power supply, the lightning protection circuit, the filter circuit, the filament conversion relay coil, the main lamp DC / DC circuit and the main LED lamp are sequentially connected together to form a main lamp loop; the direct-current power supply, the lightning protection circuit, the filter circuit, the first filament conversion relay contact, the auxiliary lamp DC / DC circuit and the auxiliary LED lamp are sequentially connected together to form an auxiliary lamp loop; by adopting the filter circuit, the redundancy switching circuit and the power supply adjusting circuit, the bypass alternating current electrified railway traction current interference and the lighting interference of a common mode and a differential mode on the LED lamps can be filtered out, wrong lighting is prevented, the redundancy switching circuit judges the current in a loop, when the main LED lamp is broken, the auxiliary LED lamp is switched to be lightened, and the safety of the main LED lamp is ensured. And the monitoring of the railway signal LED lamp filament is realized.

Description

Technical Field

[0001] The present invention relates to the technical field of railway signal LED lights, and in particular to a railway signal LED filament monitoring device and method. Background Art

[0002] Railway signal fixed signal machine color light signal machines are divided into incandescent lamp signal machines and LED lamp signal machines according to different light sources. The currently widely used LED signal machine light source is an LED lamp panel composed of dot matrix LED diodes. The LED signal machine with dot-type LED as the light source is the product of some manufacturers. The lighting voltage regulating device and the filament breakage monitoring and switching device combined with incandescent lamps, LED panel lights, and dot-type LED light sources outdoors are also called railway signal lighting units.

[0003] Railway signal lighting units are classified into the following types according to the control technology of the filament breakage monitoring and switching device: relay control type, which realizes switch control through relays, has a simple structure but a high maintenance frequency; electronic control type, which uses semiconductor devices (such as transistors and thyristors) to realize contactless control and has higher reliability; intelligent type (microprocessor control), which integrates a microprocessor and supports functions such as status monitoring, fault diagnosis, and remote communication, and can real-time feedback parameters such as current and voltage. Its voltage regulating device is generally an AC transformer. There are many domestic and foreign manufacturers of the above several types of lighting units. The common point is that they are all AC lighting units. The lighting power input end is generally AC110V and AC220V, and usually includes a transformer and an output rectifier circuit.

[0004] Analyzing the AC lighting unit, in order to achieve long-distance lighting of up to dozens of kilometers, using an AC power supply as the lighting power supply has the following disadvantages: there is a capacitive effect on the AC transmission cable. At the same time, in the electrified section, the AC traction current of the rail is as large as 300 - 1000A, and it is laid parallel to the transmission cable for dozens of kilometers, forming common-mode and differential-mode interference. Charge will also accumulate as the current flows. When it reaches a certain level, it will break through the threshold value composed of the rectifier circuit and the light-emitting diode in series, and instantly light up the LED lamp panel composed of light-emitting diodes, resulting in false display.

[0005] There is a capacitive effect between the core wires of the railway signal machine lighting transmission cable and to the ground, which will generate leakage current. The leakage current component formed by long-distance transmission of AC power frequency is much larger than the current value of the LED itself. It is no longer reliable to use the current value as the judgment threshold for the signal machine to light up and turn off in its control and acquisition circuit. It may occur that when the LED is disconnected, the indoor control and acquisition circuit can still collect the leakage current, resulting in incorrect judgment of the interlock and confusion of the system logic; as well as the capacitive effect and common-mode and differential-mode interference of the existing lighting control system transmission channel. Summary of the Invention

[0006] The present invention provides a railway signal LED filament monitoring device and method that can monitor the LED filament and has no capacitive effect, common-mode and differential-mode interference.

[0007] To solve the above problems, one of the technical solutions of the present invention is achieved in the following way: A railway signal LED filament monitoring device includes a DC power supply, a DC lighting unit, and a DC LED lamp; The DC lighting unit includes a lightning protection circuit, a filtering circuit, a redundancy switching circuit, a power adjustment circuit, and a filament status monitoring circuit; the power adjustment circuit includes a main lamp DC / DC circuit and a secondary lamp DC / DC circuit; the DC LED lamp includes a main LED lamp and a secondary LED lamp; the redundancy switching circuit includes a filament conversion relay coil and a first filament conversion relay contact; the filament status monitoring circuit includes a second filament conversion relay contact and a third filament conversion relay contact; Among them, the DC power supply, the lightning protection circuit, the filtering circuit, the filament conversion relay coil, the main lamp DC / DC circuit, and the main LED lamp are sequentially connected together to form a main lamp circuit; Among them, the DC power supply, the lightning protection circuit, the filtering circuit, the first filament conversion relay contact, the secondary lamp DC / DC circuit, and the secondary LED lamp are sequentially connected together to form a secondary lamp circuit.

[0008] The above-mentioned main lamp DC / DC circuit and secondary lamp DC / DC circuit have the same structure. The main lamp DC / DC circuit includes a first capacitor, a second capacitor, a first inductor, and an isolated DC / DC. The two ends of the first capacitor are respectively connected between the positive power supply and the negative power supply. The two ends of the second capacitor are respectively connected between the positive power supply and the negative power supply. A first inductor is connected to the positive power supply at the position before the first capacitor and the second capacitor. An isolated DC / DC is connected between the positive power supply and the negative power supply at the position on one side of the second capacitor.

[0009] The above-mentioned filtering circuit includes a second inductor, a third inductor, a fourth inductor, a third capacitor, and a fourth capacitor; the positive power supply is connected to the second inductor, the negative power supply is connected to the third inductor, the third capacitor is connected in parallel on one side of the second inductor and the third inductor, the third capacitor and the fourth capacitor are connected in parallel together, and a fourth inductor is connected to the positive power supply line at the position between the third capacitor and the fourth capacitor.

[0010] The above-mentioned lightning protection circuit includes a first gas discharge tube, a second gas discharge tube, a first varistor, and a second varistor. One end of the first gas discharge tube is connected to the positive power supply line, and the other end of the first gas discharge tube is connected to the first varistor grounded; one end of the second gas discharge tube is connected to the negative power supply line, and the other end of the second gas discharge tube is connected to the second varistor grounded.

[0011] The second technical solution of the present invention is achieved in the following manner: A method for monitoring the filament of a railway signal LED, comprising: Determine whether the main lamp circuit current value is higher than the current threshold n; In response, the coil of the filament conversion relay picks up, and at the same time, the contacts of the first filament conversion relay disconnect, disconnecting the DC power supply from the secondary lamp circuit, turning on the main LED lamp, and the main LED lamp is normal; In response to no, the coil of the filament conversion relay drops, and at the same time, the contacts of the first filament conversion relay close, connecting the DC power supply to the secondary lamp circuit, turning on the secondary LED lamp, and the main LED lamp is filament - broken.

[0012] The above - mentioned normal main LED lamp includes that when the main lamp circuit current value is higher than the current threshold n, the coil of the filament conversion relay picks up, and at the same time, the contacts of the first filament conversion relay disconnect, the contacts of the second filament conversion relay close, and the contacts of the third filament conversion relay disconnect. The state where the contacts of the second filament conversion relay close or the contacts of the third filament conversion relay disconnect indicates that the main LED lamp is normal.

[0013] The above - mentioned filament - broken main LED lamp includes that when the main lamp circuit current value is lower than the current threshold n, the coil of the filament conversion relay drops, and at the same time, the contacts of the first filament conversion relay close, the contacts of the second filament conversion relay disconnect, and the contacts of the third filament conversion relay close. The state where the contacts of the second filament conversion relay disconnect and the contacts of the third filament conversion relay close indicates that the main LED lamp is filament - broken.

[0014] The present invention has the following advantages compared with the prior art: 1. By adopting a filter circuit, a redundant switching circuit, and a power supply adjustment circuit, the present invention can filter out the interference of the bypass AC electrified railway traction current and the common - mode and differential - mode interference on the DC LED lamp lighting, prevent incorrect lighting, and through the judgment of the current in the circuit by the redundant switching circuit, when the main LED lamp is filament - broken, it switches to the secondary LED lamp to light up, realizing the monitoring of the railway signal LED filament.

[0015] 2. By using a DC power supply at the input end, the present invention has no capacitive effect, small leakage current, small attenuation, and long transmission distance, avoiding the problem that the filament relay does not drop due to the leakage current caused by the cable working capacitance of the industrial frequency alternating current. Brief Description of the Drawings

[0016] The following further describes in detail the specific embodiments of the present invention with reference to the drawings.

[0017] Figure 1 It is a schematic diagram of the device structure of Embodiment 1 of the present invention.

[0018] Figure 2It is a schematic circuit diagram of the redundancy switching circuit in Embodiment 1 of the present invention.

[0019] Figure 3 It is a schematic circuit diagram of the main lamp DC / DC circuit in Embodiment 1 of the present invention.

[0020] Figure 4 It is a schematic circuit diagram of the lightning protection circuit and the filtering circuit in Embodiment 1 of the present invention.

[0021] Figure 5 It is a schematic circuit diagram of the filament state monitoring circuit in Embodiment 1 of the present invention.

[0022] In the figure: 1-main LED lamp, 2-secondary LED lamp, 3-filament conversion relay coil, 4-first filament conversion relay contact, 5-second filament conversion relay contact, 6-third filament conversion relay contact, 7-isolated DC / DC, C1-first capacitor, C2-second capacitor, L1-first inductor, L2-second inductor, L3-third inductor, L4-fourth inductor, C3-third capacitor, C4-fourth capacitor, G1-first gas discharge tube, G2-second gas discharge tube, RV1-first varistor, RV2-second varistor. Specific embodiments

[0023] The present invention is not limited by the following embodiments, and the specific implementation manners can be determined according to the technical solutions of the present invention and the actual situation.

[0024] Embodiment 1: As Figures 1-5 shown, Embodiment 1 of the present invention discloses a railway signal LED filament monitoring device, including a DC power supply, a DC lighting unit and a DC LED lamp; The DC lighting unit includes a lightning protection circuit, a filtering circuit, a redundancy switching circuit, a power supply adjustment circuit and a filament state monitoring circuit; the power supply adjustment circuit includes a main lamp DC / DC circuit and a secondary lamp DC / DC circuit; the DC LED lamp includes a main LED lamp 1 and a secondary LED lamp 2; the redundancy switching circuit includes a filament conversion relay coil 3 and a first filament conversion relay contact 4; the filament state monitoring circuit includes a second filament conversion relay contact 5 and a third filament conversion relay contact 6; Among them, the DC power supply, the lightning protection circuit, the filtering circuit, the filament conversion relay coil 3, the main lamp DC / DC circuit and the main LED lamp 1 are connected in sequence to form a main lamp loop; Among them, the DC power supply, the lightning protection circuit, the filtering circuit, the first filament conversion relay contact 4, the secondary lamp DC / DC circuit and the secondary LED lamp 2 are connected in sequence to form a secondary lamp loop.

[0025] The above DC power supply can be direct current formed by rectifying a conventional AC 100~250V power frequency alternating current power supply, or it can be a DC power supply provided by a signal system power supply panel. The power supply voltage is adjusted according to the transmission distance, transmission voltage loss, and the voltage requirement of the terminal load LED lamp.

[0026] The above redundant switching circuit is mainly implemented by a filament conversion relay, which is a group of current relays connected in series in the main lamp circuit. When the current in the main lamp circuit is higher than the upper threshold (current threshold n) or lower than the upper threshold (current threshold n), the filament conversion relay picks up or drops, thereby realizing the switching between the main LED lamp 1 and the auxiliary LED lamp 2. Specifically: When the current value in the main lamp circuit is higher than the current threshold n, the coil 3 of the filament conversion relay picks up, and at the same time, the contact 4 of the first filament conversion relay disconnects, so that the DC power supply disconnects the connection with the auxiliary lamp circuit, and the main LED lamp 1 lights up, and the main LED lamp 1 is normal; When the current value in the main lamp circuit is lower than the current threshold n, the coil 3 of the filament conversion relay drops, and at the same time, the contact 4 of the first filament conversion relay closes, so that the DC power supply connects with the auxiliary lamp circuit, and the auxiliary LED lamp 2 lights up, and the main LED lamp 1 is filament broken; Thus, after the main LED lamp 1 is filament broken, the DC power supply is connected to the auxiliary lamp circuit, and the purpose of switching to the auxiliary LED lamp 2 lighting is achieved.

[0027] The above DC LED lamp can be a matrix lamp panel or a point light source composed of several point light-emitting bodies. The main differences lie in the different current voltages of the light-emitting body LED lamps and the different thresholds of redundant switching.

[0028] As Figure 3 shown, the main lamp DC / DC circuit and the auxiliary lamp DC / DC circuit have the same structure. The main lamp DC / DC circuit includes a first capacitor C1, a second capacitor C2, a first inductor L1, and an isolated DC / DC 7. The two ends of the first capacitor C1 are respectively connected between the positive power supply and the negative power supply. The two ends of the second capacitor C2 are respectively connected between the positive power supply and the negative power supply. A first inductor L1 is connected to the positive power supply at the position before the first capacitor C1 and the second capacitor C2. An isolated DC / DC 7 is connected between the positive power supply and the negative power supply at the position on one side of the second capacitor C2.

[0029] Through the main lamp DC / DC circuit and the auxiliary lamp DC / DC circuit above, that is, through two groups of main and auxiliary DC / DC isolation step-down circuits, the DC power supply is converted into an AC high-frequency power supply through a DC switching circuit, and after voltage regulation, isolation, rectification and voltage stabilization by the isolated DC / DC7 transformer, a constant voltage DC power supply for lighting the LED lamp is output; thus, by adjusting the frequency of converting DC to high-frequency AC, the voltage transformation ratio can be adjusted to stabilize the output power supply voltage; the switching power supply characteristics of the isolated DC / DC7 enable it to have the ability to block the passage of AC power, which can prevent the interference of AC electrified traction current to the DC lighting unit, and through the isolated DC / DC7 and the capacitors and inductors of the peripheral circuit, the main lamp DC / DC circuit and the auxiliary lamp DC / DC circuit are formed to achieve wide-range DC voltage input and DC voltage output.

[0030] As Figure 4 shown, the filter circuit includes a second inductor L2, a third inductor L3, a fourth inductor L4, a third capacitor C3 and a fourth capacitor C4; the positive pole of the power supply is connected with the second inductor L2, the negative pole of the power supply is connected with the third inductor L3, the third capacitor C3 is connected in parallel on one side of the second inductor L2 and the third inductor L3, the third capacitor C3 and the fourth capacitor C4 are connected in parallel together, and the fourth inductor L4 is connected on the positive pole line of the power supply between the third capacitor C3 and the fourth capacitor C4.

[0031] The above filter circuit is a four-terminal network of a low-pass filter, which has great suppression and bypass for power frequency and above frequencies to resist the AC interference of the electrified traction current to the DC lighting circuit, and has extremely small attenuation for the DC lighting power supply signal. Thus, the common-mode and differential-mode interference signals appearing in the transmission cable are filtered out, and the DC power supply one is converted into the DC power supply two.

[0032] As Figure 4 shown, the lightning protection circuit includes a first gas discharge tube G1, a second gas discharge tube G2, a first varistor RV1 and a second varistor RV2. One end of the first gas discharge tube G1 is connected to the positive pole line of the power supply, and the other end of the first gas discharge tube G1 is connected with the first varistor RV1 grounded; one end of the second gas discharge tube G2 is connected to the negative pole line of the power supply, and the other end of the second gas discharge tube G2 is connected with the second varistor RV2 grounded.

[0033] The above lightning protection circuit is a longitudinal surge protection circuit designed at the entrance end of the DC lighting unit to prevent lightning intrusion.

[0034] In summary, by using a DC power supply at the input end, the present invention has no capacitive effect, small leakage current, small attenuation, long transmission distance, and avoids the problem that the filament relay does not drop due to the leakage current caused by the cable working capacitance of the power frequency alternating current.

[0035] By adopting a filtering circuit, a redundant switching circuit and a power adjustment circuit, the present invention can filter out the interference of the bypass AC electrified railway traction current and the common-mode and differential-mode interference on the lighting of the DC LED lamp, prevent mis-lighting, and through the judgment of the current in the loop by the redundant switching circuit, when the main LED lamp 1 is filament-broken, it switches to the secondary LED lamp 2 to light up, realizing the monitoring of the railway signal LED filament.

[0036] Embodiment 2: The embodiment of the present invention discloses a method for monitoring the filament of a railway signal LED, including: Judging whether the main lamp loop current value is higher than the current threshold n; In response to yes, the coil 3 of the filament conversion relay is energized, and at the same time, the contact 4 of the first filament conversion relay is disconnected, so that the DC power supply disconnects the connection with the secondary lamp loop, and the main LED lamp 1 lights up, and the main LED lamp 1 is normal; In response to no, the coil 3 of the filament conversion relay drops, and at the same time, the contact 4 of the first filament conversion relay closes, so that the DC power supply connects with the secondary lamp loop, and the secondary LED lamp 2 lights up, and the main LED lamp 1 is filament-broken.

[0037] Among them, when the main LED lamp 1 is normal, it includes that when the main lamp loop current value is higher than the current threshold n, the coil 3 of the filament conversion relay is energized, and at the same time, the contact 4 of the first filament conversion relay is disconnected, the contact 5 of the second filament conversion relay closes, and the contact 6 of the third filament conversion relay is disconnected. The closed state of the contact 5 of the second filament conversion relay or the disconnected state of the contact 6 of the third filament conversion relay indicates that the main LED lamp 1 is normal.

[0038] Among them, when the main LED lamp 1 is filament-broken, it includes that when the main lamp loop current value is lower than the current threshold n, the coil 3 of the filament conversion relay drops, and at the same time, the contact 4 of the first filament conversion relay closes, the contact 5 of the second filament conversion relay is disconnected, and the contact 6 of the third filament conversion relay closes. The disconnected state of the contact 5 of the second filament conversion relay and the closed state of the contact 6 of the third filament conversion relay indicate that the main LED lamp 1 is filament-broken.

[0039] Embodiment 3: As Figure 5 shown, the embodiment of the present invention discloses a filament normal / broken alarm device. By connecting the filament state monitoring circuit of the present invention with an external alarm device, that is, connecting the contact 5 of the second filament conversion relay and the contact 6 of the third filament conversion relay with the external alarm device. Thus, the external alarm device collects the contact states of the contact 5 of the second filament conversion relay and the contact 6 of the third filament conversion relay, judges whether there is a filament-broken situation according to the contact states, and outputs and issues an alarm for the judged situation. Specifically: When the current value of the main lamp circuit is higher than the current threshold n, the filament conversion relay coil 3 is pulled up. At the same time, the first filament conversion relay contact 4 is disconnected, the second filament conversion relay contact 5 is closed, and the third filament conversion relay contact 6 is disconnected. The external alarm device collects the state of the second filament conversion relay contact 5 being closed or the third filament conversion relay contact 6 being disconnected to give a normal alarm for the main LED lamp 1. When the current value of the main lamp circuit is lower than the current threshold n, the filament conversion relay coil 3 drops. At the same time, the first filament conversion relay contact 4 is closed, the second filament conversion relay contact 5 is disconnected, and the third filament conversion relay contact 6 is closed. The external alarm device collects the state of the second filament conversion relay contact 5 being disconnected and the third filament conversion relay contact 6 being closed to give a broken filament alarm for the main LED lamp 1.

Claims

1. A railway signal LED filament monitoring device, characterized in that, It includes a DC power supply, a DC lighting unit, and a DC LED lamp; The DC lighting unit includes a lightning protection circuit, a filtering circuit, a redundant switching circuit, a power adjustment circuit, and a filament status monitoring circuit; the power adjustment circuit includes a main lamp DC / DC circuit and a secondary lamp DC / DC circuit; the DC LED lamp includes a main LED lamp and a secondary LED lamp; the redundant switching circuit includes a filament conversion relay coil and a first filament conversion relay contact; the filament status monitoring circuit includes a second filament conversion relay contact and a third filament conversion relay contact; Among them, the DC power supply, the lightning protection circuit, the filtering circuit, the filament conversion relay coil, the main lamp DC / DC circuit, and the main LED lamp are connected in sequence to form a main lamp loop; Among them, the DC power supply, the lightning protection circuit, the filtering circuit, the first filament conversion relay contact, the secondary lamp DC / DC circuit, and the secondary LED lamp are connected in sequence to form a secondary lamp loop.

2. The railway signal LED filament monitoring device according to claim 1, characterized in that, The main lamp DC / DC circuit and the secondary lamp DC / DC circuit have the same structure. The main lamp DC / DC circuit includes a first capacitor, a second capacitor, a first inductor, and an isolated DC / DC. The two ends of the first capacitor are respectively connected between the positive power supply and the negative power supply. The two ends of the second capacitor are respectively connected between the positive power supply and the negative power supply. A first inductor is connected to the positive power supply at the position before the first capacitor and the second capacitor. An isolated DC / DC is connected between the positive power supply and the negative power supply at the position on one side of the second capacitor.

3. The railway signal LED filament monitoring device according to claim 1, characterized in that, The filtering circuit includes a second inductor, a third inductor, a fourth inductor, a third capacitor, and a fourth capacitor; the positive power supply is connected to the second inductor, the negative power supply is connected to the third inductor, the third capacitor is connected in parallel on one side of the second inductor and the third inductor, the third capacitor and the fourth capacitor are connected in parallel together, and a fourth inductor is connected to the positive power supply line at the position between the third capacitor and the fourth capacitor.

4. The railway signal LED filament monitoring device according to claim 1, characterized in that, The lightning protection circuit includes a first gas discharge tube, a second gas discharge tube, a first varistor, and a second varistor. One end of the first gas discharge tube is connected to the positive power supply line, and the other end of the first gas discharge tube is connected to the first varistor grounded; one end of the second gas discharge tube is connected to the negative power supply line, and the other end of the second gas discharge tube is connected to the second varistor grounded.

5. A method for monitoring the filament of a railway signal LED, characterized in that, It includes: Judge whether the current value of the main lamp loop is higher than the current threshold n; In response to yes, the filament conversion relay coil is pulled up, and at the same time, the first filament conversion relay contact is disconnected, so that the DC power supply is disconnected from the secondary lamp loop, the main LED lamp is lit, and the main LED lamp is normal; In response to no, the filament conversion relay coil drops, and at the same time, the first filament conversion relay contact closes, so that the DC power supply is connected to the secondary lamp loop, the secondary LED lamp is lit, and the main LED lamp is filament broken.

6. A method for monitoring the filament of a railway signal LED according to claim 5, characterized in that, The main LED lamp is normal, including, When the current value of the main lamp loop is higher than the current threshold n, the filament conversion relay coil is pulled up, and at the same time, the first filament conversion relay contact is disconnected, the second filament conversion relay contact closes, and the third filament conversion relay contact is disconnected. The state of the second filament conversion relay contact closing or the third filament conversion relay contact disconnecting indicates that the main LED lamp is normal.

7. A method for monitoring the filament of a railway signal LED according to claim 5, characterized in that, The main LED lamp is filament broken, including, When the main lamp circuit current value is lower than the current threshold n, the filament conversion relay coil drops. At the same time, the contacts of the first filament conversion relay close, the contacts of the second filament conversion relay open, and the contacts of the third filament conversion relay close. The state where the contacts of the second filament conversion relay open and the contacts of the third filament conversion relay close indicates that the main LED lamp is filament broken.

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