Signal lamp electricity taking circuit and intelligent traffic system

Abstract

The utility model discloses a signal lamp electricity taking circuit and an intelligent traffic system. The signal lamp electricity taking circuit is composed of a signal lamp power supply line, an energy storage unit, a first impact current suppression circuit, a second impact current suppression circuit, a sampling circuit, a comparator, a first switch and a second switch. The energy storage unit stores energy based on the signal lamp power supply line and supplies power to the external load, when the working voltage of the external load is low, the comparator outputs a low level, the first switch and the second switch are switched off, and the first impact current suppression circuit suppresses large impact current; when the working voltage of the external load is high, the comparator outputs a high level, and the first switch and the second switch are closed, so that the second impact current suppression circuit is connected to the first impact current suppression circuit in parallel, the suppression impedance is reduced, and suppression of small impact current is realized; based on the above, the power taking circuit can periodically suppress the charging current of the energy storage unit under the condition that the signal lamp flickers, and automatically switch the adaptive suppression circuit, thereby preventing the external load from being damaged by voltage impact, and improving the safety and reliability of the system.

Description

Technical Field

[0001] The utility model relates to the technical field of intelligent transportation, in particular to a power taking circuit for signal lights and an intelligent transportation system. Background Art

[0002] Intelligent transportation is a new mode of transportation development based on the combination of networks such as the Internet and the Internet of Things, with intelligent road networks, intelligent equipment, intelligent travel, and intelligent management as important contents, and having the basic characteristics of information connectivity, real-time monitoring, management collaboration, and integration of people and things.

[0003] In intelligent transportation, due to the high position and good vision of the lamp posts of traffic lights, they are the best positions to install various sensing devices. However, when powering various sensing devices, it is not possible to add a power supply line by breaking the road and threading wires at existing intersections.

[0004] The existing technology is to take power from the existing signal light wires to supply power to various sensing devices. And in order to avoid the problem of power interruption during the flashing of traffic lights, it is necessary to configure a capacitor with a large capacity for energy storage in the power taking circuit, and the capacitor supplies power to the sensing devices during the flashing and power interruption of traffic lights. However, this power supply method still has the following problems: Since the capacitor is used for energy storage to supply power to the sensing devices, an impact current will be generated at the moment of power interruption, and the impact current will damage the external load, and this problem will exist every time there is a power interruption.

[0005] The above information disclosed in this background art is only used to increase the understanding of the background art of this application. Therefore, it may include prior art that is not known to those of ordinary skill in the art. Summary of the Invention

[0006] In view of the problems pointed out in the background art, the utility model provides a power taking circuit for signal lights and an intelligent transportation system, which periodically suppress the charging current of the energy storage unit when the signal lights are flashing, and automatically switch to an adapted suppression circuit according to the size of the external load. The impact current generated during the flashing of the signal lights is suppressed by the suppression circuit, avoiding damage to the external load caused by voltage impact, and improving the safety and reliability of the external load taking power from the signal light power supply line during use.

[0007] To achieve the above-mentioned utility model purpose, the utility model adopts the following technical solutions:

[0008] A power taking circuit for signal lights is provided, including a signal light power supply line and an energy storage unit; the energy storage unit stores energy based on the signal light power supply line, and the stored energy is used to supply power to an external load; it is characterized in that it further includes:

[0009] A first impact current suppression circuit, whose input end is connected to the signal light power supply line, and whose output end is connected to the energy storage unit;

[0010] A second inrush current suppression circuit, connected in parallel with the first inrush current suppression circuit;

[0011] A sampling circuit, configured to collect the output voltage of the energy storage unit;

[0012] A comparator, whose non-inverting input terminal is connected to the output terminal of the sampling circuit, and whose inverting input terminal is connected to a reference voltage;

[0013] A first switch, whose input terminal is connected to the output terminal of the comparator;

[0014] A second switch, whose input terminal is connected to the output terminal of the first switch, and whose output terminal is connected in series to the second inrush current suppression circuit;

[0015] Wherein, the reference voltage is configured such that: when the operating voltage of the external load is lower than a threshold value, the comparator outputs a low level; when the operating voltage of the external load is higher than the threshold value, the comparator outputs a high level.

[0016] Compared with the prior art, the advantages and positive effects of the present utility model are as follows: In the power supply taking circuit of the signal lamp proposed by the present utility model, two inrush current suppression circuits are added between the power supply line of the signal lamp and the energy storage unit, and the sampling circuit samples the output voltage of the energy storage unit; when the operating voltage of the external load is low and the energy storage of the energy storage unit is small, the inrush current generated during the flashing and power-off period of the signal lamp is relatively large. Since the voltage sampled by the sampling circuit is low, the input of the non-inverting terminal of the comparator is lower than the input of the inverting terminal, causing the comparator to output a low level, the first switch cannot be turned on, and the second switch cannot be turned on either. The first inrush current suppression circuit is connected to the circuit to suppress the relatively large inrush current; when the operating voltage of the external load is high and the energy storage of the energy storage unit is large, the inrush current generated during the flashing and power-off period of the signal lamp is relatively small. Since the voltage sampled by the sampling circuit is high, the input of the non-inverting terminal of the comparator is higher than the input of the inverting terminal, causing the comparator to output a high level, the first switch is turned on, making the input of the second switch a high level, and the second switch is also turned on, so that the second inrush current suppression circuit is paralleled to the first inrush current suppression circuit, reducing the suppression impedance, thereby suppressing the relatively small inrush current; in the power supply taking circuit of the signal lamp proposed by the present utility model as described above, the energy storage unit is charged based on the power supply line of the signal lamp, and the charged energy storage supplies power to the external load. Therefore, there is no need to add a new power supply device for the external load, avoiding the situation of breaking roads and threading wires. During the flashing period of the signal lamp, the appropriate suppression circuit can be automatically switched according to the operating voltage of the external load. The inrush current generated during the flashing period of the signal lamp is suppressed by the suppression circuit, avoiding damage to the external load caused by the impact of the inrush current, and improving the safety and reliability of the external load taking power from the power supply line of the signal lamp during use.

[0017] In some embodiments of the present application, the circuit further includes: a rectifier circuit, including a first rectifier bridge, a second rectifier bridge, and a third rectifier bridge; wherein, the first rectifier bridge is used to rectify the output of the power supply line of the red signal lamp, the second rectifier bridge is used to rectify the output of the power supply line of the yellow signal lamp, and the third rectifier bridge is used to rectify the power supply line of the green signal lamp; the outputs of the three rectifier bridges are connected in parallel and then connected to the inputs of the first inrush current suppression circuit and the second inrush current suppression circuit.

[0018] In this embodiment, three rectifier bridge circuits are used to rectify the power supply lines of signal lamps of different colors, and the three rectifier outputs are connected in parallel and then output to the power-taking circuit, ensuring that as long as there is power supply in the power supply line of one color of signal lamp, the normal charging of the energy storage unit and the normal power supply of the external load can be guaranteed.

[0019] In some embodiments of the present application, the circuit further includes: a buck circuit, whose input is connected to the energy storage unit and whose output is connected to the power supply end of the external load.

[0020] The buck circuit is, for example, a voltage conversion chip, which is used to adjust the output voltage of the energy storage unit to the voltage required by the external load, and an isolated or non-isolated type can be selected.

[0021] In some embodiments of the present application, the circuit further includes: a reference voltage circuit, which is composed of a first voltage conversion chip, a first resistor, and a second resistor; wherein, the input of the first voltage conversion chip is connected to the output of the buck circuit, and its output provides the working power supply for the comparator; the first resistor and the second resistor are connected in series, one end is grounded, and the other end is connected to the output of the first voltage conversion chip; the inverting end of the comparator is connected between the first resistor and the second resistor.

[0022] In some embodiments of the present application, the reference voltage circuit further includes: a filter circuit, which is connected in parallel with the circuit in which the first resistor and the second resistor are connected in series.

[0023] The reference voltage circuit takes the output of the buck circuit as the input voltage, and an isolated or non-isolated type can be selected. Its output provides the working voltage for the comparator on the one hand, and provides the reference voltage input to the inverting end of the comparator through the voltage dividing circuit composed of the first resistor and the second resistor on the other hand; this reference voltage needs to meet that when the working voltage of the external load is less than the threshold, the input of the non-inverting end of the comparator is lower than this reference voltage, so that the comparator outputs a low level, and when the working voltage of the external load is higher than the threshold, the input of the non-inverting end of the comparator is higher than this reference voltage, so that the comparator outputs a high level. When the output voltage of the buck circuit is equal to the working voltage required by the comparator and isolation is not required, this reference voltage circuit can be omitted.

[0024] In some embodiments of the present application, the circuit further includes: a second voltage conversion chip, whose input terminal is connected to the output of the buck circuit, and whose output terminal provides a switching power supply for the first switch.

[0025] In some embodiments of the present application, the first switch is an optocoupler, and the output terminal of the comparator is connected to the input terminal of the optocoupler through a third resistor; or, the first switch is an NPN transistor, whose base is the input terminal and whose emitter is the output terminal; its collector is connected to the output of the second voltage conversion chip.

[0026] In some embodiments of the present application, the second switch is an NMOS transistor, whose gate is the input terminal and whose drain is the output terminal; its source is connected to the output of the rectification circuit.

[0027] The second voltage conversion chip, the first switch, and the second switch using an NMOS transistor realize replacing the high-side PMOS transistor with a low-side MOS transistor as a switch, effectively saving the circuit cost, and at the same time replacing the relay, solving the problem of the switch life of the relay.

[0028] In some embodiments of the present application, the second switch is a relay.

[0029] For scenarios where power-off is not frequent, the NMOS transistor can be replaced with a relay to reduce the circuit cost.

[0030] The present utility model also proposes an intelligent transportation system, including a power supply line for red signal lights, a power supply line for green signal lights, a power supply line for yellow signal lights, and a sensing device as an external load, and further including the signal light power-taking circuit as described above.

[0031] In this intelligent transportation system, a storage unit is charged through the power supply circuit of any color signal lamp. The energy stored in the storage unit is used to supply power to the sensing devices serving as external loads. Here, the sensing devices include, for example, sensors for monitoring vehicle flow, sensors for monitoring vehicle speed, etc. The storage unit includes, for example, large-capacity capacitors or rechargeable batteries, etc. During the period when the signal lamp flashes and loses power, the voltage of the storage unit is sampled by the sampling circuit and output to the non-inverting input terminal of the comparator. When the operating voltage of the sensing device is low, the energy stored in the storage unit is less, and the impact current generated during the period when the signal lamp flashes and loses power is relatively large. The voltage sampled by the sampling circuit is lower than the set threshold value, so the input of the non-inverting terminal of the comparator is lower than the input of the inverting terminal, causing the comparator to output a low level. The first switch cannot conduct, and the second switch cannot conduct either, enabling the first impact current suppression circuit to be connected to the circuit to suppress the relatively large impact current. When the operating voltage of the sensing device is high, the energy stored in the storage unit is more, and the impact current generated during the period when the signal lamp flashes and loses power is relatively small. The voltage sampled by the sampling circuit is higher than the set threshold value, so the input of the non-inverting terminal of the comparator is higher than the input of the inverting terminal, causing the comparator to output a high level. The first switch conducts, making the input of the second switch a high level, and the second switch also conducts, so that the second impact current suppression circuit is connected in parallel to the first impact current suppression circuit, reducing the suppression impedance, thereby suppressing the relatively small impact current. Thus, it realizes automatically switching the adapted suppression circuit according to the operating voltage of the sensing device, suppressing the impact current received by the sensing device through the suppression circuit to avoid its damage, improving the safety and reliability of the sensing devices powered from the signal lamp power supply line in the intelligent transportation system, and ensuring the stability of the entire intelligent transportation system.

[0032] After reading the specific embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become clearer. Brief Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the accompanying drawings required for use in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0034] Figure 1 It is a schematic structural diagram of a signal lamp system in the prior art;

[0035] Figure 2 It is a schematic circuit structure diagram of the signal lamp power supply circuit given in this application;

[0036] Figure 3 It is the circuit structure of the signal lamp power supply circuit given in an embodiment of this application;

[0037] Figure 4 The circuit structure of the signal lamp power supply circuit given in an embodiment of the present application;

[0038] Figure 5 The circuit structure of the signal lamp power supply circuit given in an embodiment of the present application;

[0039] Figure 6 The circuit structure of the signal lamp power supply circuit given in an embodiment of the present application;

[0040] Figure 7 The circuit structure of the signal lamp power supply circuit given in an embodiment of the present application;

[0041] Figure 8 The circuit structure of the signal lamp power supply circuit given in an embodiment of the present application;

[0042] Figure 9 The circuit structure of the signal lamp power supply circuit given in an embodiment of the present application;

[0043] Figure 10 The system structure schematic diagram of the intelligent transportation system given in the present application. Detailed implementation manners

[0044] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

[0045] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0046] The terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise specified, the meaning of "plural" is two or more.

[0047] In the description of the present application, it should be noted that unless otherwise clearly specified and defined, the terms "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0048] In the present utility model, unless otherwise clearly specified and defined, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over", and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "below", "beneath", and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0049] The following disclosure provides many different embodiments or examples for implementing different structures of the present utility model. To simplify the disclosure of the present utility model, the components and settings of specific examples are described below. Of course, they are only examples and are not intended to limit the present utility model. In addition, the present utility model may repeat reference numerals and / or reference letters in different examples. This repetition is for the purpose of simplification and clarity, and does not itself indicate the relationship between the various embodiments and / or settings discussed. In addition, the present utility model provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.

[0050] In the present application, the intelligent transportation system, such as Figure 1 As shown, a signal lamp pole and signal lamps are installed at an intersection, which usually include a red signal lamp, a green signal lamp, and a yellow signal lamp, and a signal lamp power supply line (shown as the thick black line in the figure) for supplying power to the signal lamps is laid under the road surface. With the development of intelligent transportation, due to the wide field of vision on the signal lamp pole, sensing devices such as traffic flow monitors and vehicle speed monitors are added to the signal lamp pole. Subsequently, there is a need to supply power to the sensing devices. However, laying new power supply lines to supply power to the sensing devices requires ground-breaking construction, which obviously has the problems of high construction difficulty and high cost. Therefore, it is the most suitable solution to obtain power for the sensing devices from the existing signal lamp power supply line laid under the road surface.

[0051] Based on the above, the present application proposes a signal lamp power acquisition circuit, as Figure 2 shown, including:

[0052] The signal lamp power supply circuit includes one or more of the red signal lamp power supply circuit, the green signal lamp power supply circuit, and the yellow signal lamp power supply circuit.

[0053] The energy storage unit is designed with a large-capacity capacitor or a rechargeable battery. It is connected to the signal lamp power supply circuit and charges based on the signal lamp power supply circuit. The charged energy is used to supply power to external devices.

[0054] The first inrush current suppression circuit is implemented with a power resistor. Its input terminal is connected to the signal lamp power supply circuit, and its output terminal is connected to the energy storage unit.

[0055] The second inrush current suppression circuit is implemented with a power resistor and is connected in parallel with the first inrush current suppression circuit.

[0056] The sampling circuit collects the output voltage of the energy storage unit. The output voltage of the energy storage unit is adapted to the requirements of the external load. When the operating voltage of the external load is low, the energy storage of the energy storage unit is less; when the operating voltage of the external load is high, the energy storage of the energy storage unit is more. The sampling circuit can be designed with a general resistor voltage division circuit.

[0057] Comparator U5, its non-inverting input terminal is connected to the output terminal of the sampling circuit, and its inverting input terminal is connected to the reference voltage V1. The reference voltage V1 is set such that when the operating voltage of the external load is lower than the threshold, the voltage sampled from the energy storage unit is lower than the reference voltage V1, causing the comparator to output a low level; when the operating voltage of the external load is higher than the threshold, the voltage sampled from the energy storage unit is higher than the reference voltage V1, causing the comparator to output a high level.

[0058] The first switch Q1, its input terminal is connected to the output terminal of the comparator. When the comparator outputs a low level, the first switch is disconnected; when the comparator U5 outputs a high level, the first switch Q1 is closed.

[0059] The second switch Q2, its input terminal is connected to the output terminal of the first switch Q1, and its output terminal is connected in series to the second inrush current suppression circuit. When the first switch Q1 is disconnected, the input voltage of the second switch Q2 is zero, and the second switch Q2 remains disconnected without an input voltage. The second inrush current suppression circuit is disconnected by the second switch Q2 and cannot form a parallel circuit with the first inrush current suppression circuit. When the first switch Q1 is closed, the input terminal of the second switch Q2 has a conduction voltage and also closes, enabling the second inrush current suppression circuit to be connected in parallel with the first inrush current suppression circuit.

[0060] When the second inrush current suppression circuit is connected in parallel with the first inrush current suppression circuit, the suppression impedance formed by the parallel circuit is lower than the suppression impedance of the first inrush current suppression circuit. Therefore, the first inrush current suppression circuit can be used to suppress large inrush currents, and the parallel suppression circuit can suppress smaller inrush currents.

[0061] Based on the power-taking circuit of the signal lamp given in the present application above, when the operating voltage of the external load is low and the energy storage of the energy storage unit is small, the impact current generated during the flashing and power-off period of the signal lamp is relatively large. Since the voltage sampled by the sampling circuit is low, the input of the non-inverting terminal of the comparator is lower than the input of the inverting terminal, causing the comparator U5 to output a low level. The first switch Q1 cannot conduct, and the second switch Q2 cannot conduct either. The first impact current suppression circuit is connected to the circuit to suppress the relatively large impact current. When the operating voltage of the external load is high and the energy storage of the energy storage unit is large, the impact current generated during the flashing and power-off period of the signal lamp is relatively small. Since the voltage sampled by the sampling circuit is high, the input of the non-inverting terminal of the comparator U5 is higher than the input of the reverse terminal, causing the comparator U5 to output a high level. The first switch Q1 conducts, making the input of the second switch Q2 a high level, and the second switch Q2 also conducts. As a result, the second impact current suppression circuit is paralleled to the first impact current suppression circuit, reducing the suppression impedance, thereby suppressing the relatively small impact current. In the power-taking circuit of the signal lamp proposed by the present utility model above, the energy storage unit is charged based on the power supply line of the signal lamp, and the charged energy storage supplies power to the external load. Therefore, there is no need to add a new power supply device for the external load, avoiding the situation of breaking the road and threading. During the flashing of the signal lamp, the appropriate suppression circuit can be automatically switched according to the operating voltage of the external load. The impact current generated during the flashing of the signal lamp is suppressed by the suppression circuit, avoiding damage to the external load caused by the impact of the impact current, and improving the safety and reliability of the external load taking power from the signal lamp power supply line during use.

[0062] In an embodiment of the present application, as Figure 3 shown, it further includes a rectification circuit composed of a first rectifier bridge D1, a second rectifier bridge D2, and a third rectifier bridge D3. The first rectifier bridge D1 is used to rectify the output of the power supply line R of the red signal lamp, the second rectifier bridge D2 is used to rectify the output of the power supply line Y of the yellow signal lamp, and the third rectifier bridge D3 is used to rectify the output of the power supply line G of the green signal lamp. The outputs of the three rectifier bridges are connected in parallel and then connected to the inputs of the first impact current suppression circuit and the second impact current suppression circuit.

[0063] In this embodiment, the power supply lines of different color signal lamps are rectified by three rectifier bridge circuits, and the three rectified outputs are connected in parallel to the suppression circuit, which can ensure that as long as there is power supply from the power supply line of one color of the signal lamp, the normal charging of the energy storage unit and the normal power supply of the external load can be guaranteed.

[0064] In an embodiment of the present application, as Figure 4As shown, a buck circuit U4 is connected to the output end of the energy storage unit, which is implemented by using a general voltage conversion chip or an existing buck circuit structure, and is used to adjust the output of the energy storage unit to the voltage required by the external load. The voltage conversion chip can be selected as an isolated type or a non-isolated type according to actual requirements.

[0065] While the output of the buck circuit supplies power to the external load, it can also be used to provide the switching power supply of the first switch Q1 and the operating voltage and reference voltage of the comparator U5.

[0066] In an embodiment of the present application, as Figure 5 shown, the reference voltage V1 of the comparator is provided by a reference voltage circuit, which is composed of a first voltage conversion chip U1, a first resistor R1 and a second resistor R2; wherein, the input of the first voltage conversion chip U1 is connected to the output of the buck circuit U4, and its output provides the operating power supply V2 for the comparator U5; the first resistor R1 and the second resistor R2 are connected in series, one end of the series circuit is grounded, and the other end is connected to the output of the first voltage conversion chip U1; the inverting terminal of the comparator U5 is connected between the first resistor R1 and the second resistor R2. Among them, Figure 5 a resistance voltage division circuit constitutes a sampling circuit therein, and the energy storage unit is designed as a capacitor C1.

[0067] The outputs V+ and V- of the buck circuit U4 provide the input voltage for the first voltage conversion chip U1, and an isolated type or a non-isolated type can be selected, and the selection can be made according to the circuit design requirements; on the one hand, the output of the first voltage conversion chip U1 provides the operating voltage V2 for the comparator U5, and on the other hand, its output is divided by the first resistor R1 and the second resistor R2 and then connected to the inverting terminal of the comparator U5 as the reference voltage V1 of the comparator U5. As shown before, the reference voltage V1 is set such that when the operating voltage of the external load is lower than the threshold, the voltage sampled from the energy storage unit is lower than the reference voltage V1, so that the comparator U5 outputs a low level; when the operating voltage of the external load is higher than the threshold, the voltage sampled from the energy storage unit is higher than the reference voltage, so that the comparator U5 outputs a high level. Therefore, the selection of the output of the first voltage conversion chip U1, the first resistor R1 and the second resistor R2 together determines the configuration of the reference voltage V1.

[0068] When the output voltage V+ of the buck circuit U4 is equal to the operating voltage V2 required by the comparator U5 and isolation is not required, the reference voltage circuit can be omitted.

[0069] In an embodiment of the present application, as Figure 6As shown, the switching power supply of the first switch Q1 can be provided by a separate second voltage conversion chip U3. Of course, it can also be provided by an available power supply existing in other parts of the circuit, which is not specifically limited in this embodiment. In this embodiment, the output of the buck circuit U4 serves as the input of the second voltage conversion chip U3, and the output separately provides a switching power supply for the first switch Q1. The on / off of the first switch Q1 determines the on / off of the second switch Q2. Therefore, the circuit structure composed of the second voltage conversion chip U3, the first switch Q1, and the second switch Q2 can achieve high-side control between the external load and the signal lamp power supply line. Among them, Figure 6 The first inrush current suppression circuit is designed with the first power resistor RW1, and the second inrush current suppression circuit is designed with the second power resistor RW2; in the reference voltage circuit, a filter capacitor is connected in parallel with the circuit in series with the first resistor R1 and the second resistor R2.

[0070] In an embodiment of the present application, as Figure 7 shown, the first switch Q1 is designed with an optocoupler, and the output terminal of the comparator U5 is connected to the input terminal of the optocoupler through the third resistor R3; the second switch Q2 is designed with an NMOS transistor, its gate is the input terminal, and its drain is the output terminal; its source is connected to the output of the signal lamp power supply line. The second voltage conversion chip U3, the first switch Q1, and the NMOS transistor second switch Q2 realize replacing the high-side PMOS transistor with a low-side NMOS transistor as a switch, effectively saving the circuit cost, and at the same time replacing the relay, solving the problem of the switch life of the relay.

[0071] As Figure 8 shown in an embodiment, the first switch Q1 can also be an NPN transistor, its base is the input terminal, and its emitter is the output terminal; its collector is connected to the output of the second voltage conversion chip U3.

[0072] As Figure 9 shown in an embodiment, for the scenario where the signal lamp power supply line does not lose power frequently, the second switch Q2 can be replaced with a relay to reduce the circuit design cost.

[0073] Based on the above-mentioned signal lamp power supply circuit, the present application also proposes an intelligent transportation system applying this signal lamp power supply circuit. As Figure 10 shown, the system includes a red signal lamp power supply line R, a green signal lamp power supply line G, a yellow signal lamp power supply line Y, and a sensing device X as an external load; the red signal lamp power supply line R, the green signal lamp power supply line G, and the yellow signal lamp power supply line Y are the input terminals of the signal lamp power supply circuit, and the output of the signal lamp power supply circuit is connected to the sensing device to provide a working voltage for the sensing device.

[0074] In this intelligent transportation system, the energy storage unit is charged through the power supply circuit of any color signal lamp, and the energy stored in the energy storage unit is used to supply power to the sensing device serving as an external load.

[0075] The sensing devices here are, for example, sensors for monitoring vehicle flow, sensors for monitoring vehicle speed, etc. The energy storage unit is, for example, a large-capacity capacitor or a rechargeable battery, etc.

[0076] During the period when the signal lamp flashes and loses power, the voltage of the energy storage unit is sampled by the sampling circuit and output to the non-inverting input terminal of the comparator U5. When the working voltage of the sensing device X is low, the energy stored in the energy storage unit is small, and the impact current generated during the period when the signal lamp flashes and loses power is relatively large. The voltage sampled by the sampling circuit is lower than the set threshold value, so the input of the non-inverting terminal of the comparator U5 is lower than the input of the inverting terminal, causing the comparator U5 to output a low level. The first switch Q1 cannot conduct, and the second switch Q2 cannot conduct either, enabling the first impact current suppression circuit to be connected to the circuit to suppress the relatively large impact current; when the working voltage of the sensing device X is high, the energy stored in the energy storage unit is large, and the impact current generated during the period when the signal lamp flashes and loses power is small. The voltage sampled by the sampling circuit is higher than the set threshold value, so the input of the non-inverting terminal of the comparator U5 is higher than the input of the inverting terminal, causing the comparator U5 to output a high level. The first switch Q1 conducts, making the input of the second switch Q2 a high level, and the second switch Q2 also conducts, so that the second impact current suppression circuit is paralleled to the first impact current suppression circuit, reducing the suppression impedance, thereby suppressing the relatively small impact current.

[0077] The intelligent transportation system of this application realizes automatically switching the adapted suppression circuit according to the working voltage of the sensing device X, suppresses the impact current received by the sensing device X through the suppression circuit to avoid its damage, improves the safety and reliability of the sensing device that draws power from the signal lamp power supply line in the intelligent transportation system, and ensures the stability of the entire intelligent transportation system.

[0078] In the description of the above embodiments, the specific features, structures, materials or characteristics can be combined in a suitable manner in any one or more embodiments or examples.

[0079] The above is only the specific implementation manner of the present utility model, but the protection scope of the present utility model is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present utility model should be covered within the protection scope of the present utility model. Therefore, the protection scope of the present utility model should be subject to the protection scope of the claims.

Claims

1. A signal light power supply circuit, comprising a signal light power supply circuit and an energy storage unit; the energy storage unit stores energy based on the signal light power supply circuit, and the stored energy is used to supply power to an external load; characterized in that: Also includes: A first surge current suppression circuit, an input end of which is connected to the signal light power supply circuit, and an output end of which is connected to the energy storage unit; A second inrush current suppression circuit, connected in parallel with the first inrush current suppression circuit; A sampling circuit, used for collecting the output voltage of the energy storage unit; A comparator, wherein a non-inverting terminal of the comparator is connected to the output terminal of the sampling circuit, and an inverting terminal of the comparator is connected to a reference voltage; A first switch, an input end of which is connected to the output end of the comparator; A second switch, whose input end is connected to the output end of the first switch, and whose output end is connected in series to the second inrush current suppression circuit; The reference voltage is configured such that: when the operating voltage of the external load is lower than a threshold value, the comparator outputs a low level; when the operating voltage of the external load is higher than the threshold value, the comparator outputs a high level.

2. The signal light power supply circuit according to claim 1, characterized in that: The circuit further comprises: A rectifier circuit includes a first rectifier bridge, a second rectifier bridge and a third rectifier bridge; wherein the first rectifier bridge is used to rectify the output of the red signal light power supply circuit, the second rectifier bridge is used to rectify the output of the yellow signal light power supply circuit, and the third rectifier bridge is used to rectify the green signal light power supply circuit; the outputs of the three rectifier bridges are connected in parallel to the inputs of the first inrush current suppression circuit and the second inrush current suppression circuit.

3. The signal light power supply circuit according to claim 1, characterized in that: The circuit further comprises: The step-down circuit has an input connected to the energy storage unit and an output connected to the power supply end of the external load.

4. The signal light power supply circuit according to claim 3, characterized in that: The circuit further comprises: The reference voltage circuit is composed of a first voltage conversion chip, a first resistor and a second resistor; wherein the input of the first voltage conversion chip is connected to the output of the step-down circuit, and the output of the first voltage conversion chip provides working power for the comparator; the first resistor and the second resistor are connected in series, one end of which is grounded, and the other end is connected to the output of the first voltage conversion chip; the inverting end of the comparator is connected between the first resistor and the second resistor.

5. The signal light power supply circuit according to claim 4, characterized in that: The reference voltage circuit also includes: A filter circuit is connected in parallel with a circuit in which the first resistor and the second resistor are connected in series.

6. The signal light power supply circuit according to claim 3, characterized in that: The circuit further comprises: The second voltage conversion chip has an input end connected to the output of the step-down circuit, and an output end providing a switching power supply for the first switch.

7. The signal light power supply circuit according to claim 6, characterized in that: The first switch is an optical coupler, and the output end of the comparator is connected to the input end of the optical coupler through a third resistor; or, The first switch is an NPN transistor, whose base is the input terminal and whose emitter is the output terminal; and whose collector is connected to the output of the second voltage conversion chip.

8. The signal light power supply circuit according to claim 2, characterized in that: The second switch is an NMOS tube, whose gate is the input end, whose drain is the output end; and whose source is connected to the output of the rectifier circuit.

9. The signal light power supply circuit according to claim 1, characterized in that: The second switch is a relay.

10. An intelligent traffic system, comprising a red signal light power supply circuit, a green signal light power supply circuit, a yellow signal light power supply circuit and a sensing device as an external load, characterized in that: It also includes a signal light power supply circuit as described in any one of claims 1 to 9.

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