Traffic signal lamp control circuit

Abstract

The invention relates to a traffic signal lamp control circuit, which comprises an intersection signal lamp system, a control module and a switch module corresponding to each signal lamp in a signal lamp group in the intersection signal lamp system, a first switch and a fuse of the switch module are arranged on a live wire, and a second switch of the switch module is arranged on a zero wire; each switch module is used for controlling the on or off of the first switch and the second switch under the control of the first time sequence of the control module, and normally lightening or extinguishing the corresponding signal lamp when the live wires are lapped between the signal lamps; when the live line and the zero line between the signal lamps are lapped, the fuse is burnt out to quickly cut off a loop to respond to a crosstalk fault between the lines. The signal lamps are controlled to be turned on or turned off through the two switches, a loop is rapidly cut off to respond to an inter-line crosstalk fault when the live line and the null line between the signal lamps are in lap joint, the situation that the signal lamps are turned on mistakenly is avoided, and the problem that traffic is affected due to the fact that the inter-line crosstalk fault cannot be responded in time is solved.

Description

Technical Field

[0001] This application relates to the field of traffic control technology, and particularly to a traffic signal control circuit. Background Art

[0002] Currently, most mainstream traffic signals are controlled by dedicated lines. After the wires led out from the control cabinet are concentrated and converged, they are respectively connected to each signal light at the intersection through buried pipelines to provide power transmission for all signal lights.

[0003] In such a complex wiring situation, crosstalk between wires is inevitable, and wire connection is likely to cause mis-triggering of signal lights, resulting in lights that should not be on being on and lights that should not be off being off. Moreover, such faults are difficult to troubleshoot, and if not responded to and resolved in a timely manner, it will affect traffic.

[0004] In view of the problem in the related technology that faults of crosstalk between wires cannot be responded to in a timely manner, affecting traffic, no effective solution has been proposed yet. Summary of the Invention

[0005] Based on this, in view of the above technical problems, it is necessary to provide a traffic signal control circuit that can respond to crosstalk faults between signal lights in a timely manner.

[0006] In a first aspect, in this embodiment, a traffic signal control circuit is provided, including: an intersection signal light system, a control module, and a switch module corresponding to each signal light in the signal light group of the intersection signal light system; each signal light is connected to the live wire and the neutral wire through the switch module;

[0007] The switch module includes a first switch and a second switch. The first switch and the fuse are arranged on the live wire, and the second switch is arranged on the neutral wire;

[0008] Each switch module is connected to the control module and is used to control the opening or closing of the first switch and the second switch under the control of the first timing of the control module. When there is a connection between the live wires of the signal lights, the corresponding signal lights are normally lit or extinguished;

[0009] When there is a connection between the live wire and the neutral wire of the signal lights, the fuse blows to quickly cut off the circuit to respond to the crosstalk fault.

[0010] In some of the embodiments, the first timing control of the control module includes:

[0011] When first closing the second switch in the switch module and then opening the first switch, the corresponding signal light is lit;

[0012] When first closing the first switch in the switch module and then opening the second switch, the corresponding signal light is extinguished.

[0013] In some of these embodiments, the control module is configured to control the signal lamp states of each signal lamp group in the intersection signal lamp system in a second timing.

[0014] In some of these embodiments, the first switch and the second switch are thyristor switches or relay switches.

[0015] In some of these embodiments, when the first switch has turn-off leakage, the second switch absorbs the leakage of the first switch.

[0016] In some of these embodiments, it further includes: a voltage detection circuit;

[0017] The voltage detection circuit is arranged between the neutral line and the live line and is used to detect abnormal signals of the switch module voltage.

[0018] In some of these embodiments, the voltage detection circuit includes an optocoupler voltage detection circuit, a Hall sensor voltage detection circuit, a capacitor charging type voltage detection circuit, and a metering chip voltage detection circuit.

[0019] In some of these embodiments, it further includes: a current detection circuit;

[0020] The current detection circuit is arranged between the live line and the total output and is used to detect abnormal signals of the switch module current.

[0021] In some of these embodiments, the current detection circuit includes an optocoupler current detection circuit, a Hall sensor current detection circuit, a capacitor charging type current detection circuit, and a metering chip current detection circuit.

[0022] In some of these embodiments, when the abnormal signal is detected, the corresponding signal lamp group is turned off through the control module; and the yellow lamp in the signal lamp group is controlled to flash as a warning.

[0023] Compared with the related art, the traffic signal control circuit provided in this embodiment includes an intersection signal system, a control module, and a switch module corresponding to each signal light in the signal light group of the intersection signal system; each signal light is connected to the live wire and the neutral wire through the switch module; the switch module includes a first switch and a second switch, the first switch and the fuse are arranged on the live wire, and the second switch is arranged on the neutral wire; each switch module is connected to the control module and is used to control the opening or closing of the first switch and the second switch under the control of the first time sequence of the control module, so as to normally light or extinguish the corresponding signal light when there is a connection between the live wires of the signal lights; when there is a connection between the live wire and the neutral wire of the signal lights, the fuse blows to quickly cut off the circuit to respond to the crosstalk fault between the lines. Through this embodiment, a switch is arranged on each of the live wire and the neutral wire, and the lighting or extinguishing of the signal light is controlled by two switches. When there is a connection between the live wires of the signal lights, the state of the signal light is not affected. When there is a connection between the live wire and the neutral wire of the signal lights, the circuit is quickly cut off to respond to the crosstalk fault between the lines, and the situation of mis-lighting of the signal light will not occur, solving the problem that the fault of crosstalk between the lines cannot be responded to in time and affecting the traffic.

[0024] Details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more concise and understandable. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The drawings described herein are used to provide a further understanding of the present application and form a part of the present application. The illustrative embodiments and descriptions of the present application are used to explain the present application and do not constitute an improper limitation of the present application. In the drawings:

[0026] Figure 1 is a schematic diagram of a traffic signal control circuit in the related art;

[0027] Figure 2 is a schematic diagram of a traffic signal control circuit in an embodiment;

[0028] Figure 3 is a schematic diagram of a connection between signal lights in an embodiment;

[0029] Figure 4 is a schematic diagram of the leakage situation when the switch is turned off in an embodiment;

[0030] Figure 5 is a schematic diagram of the circuit of the first switch in an embodiment;

[0031] Figure 6 is a schematic diagram of the circuit of the second switch in an embodiment;

[0032] Figure 7It is a schematic diagram of a voltage detection circuit in an embodiment;

[0033] Figure 8 It is a schematic diagram of a current detection circuit in an embodiment. Detailed implementation manners

[0034] To understand the purpose, technical solution and advantages of the present application more clearly, the present application will be described and illustrated below with reference to the accompanying drawings and embodiments.

[0035] Unless otherwise defined, the technical terms or scientific terms involved in the present application shall have the general meanings understood by those with ordinary skills in the technical field to which the present application belongs. In the present application, words such as "a", "an", "one kind", "the", "these", etc. do not indicate a limitation in quantity, and they can be singular or plural. The terms "include", "comprise", "have" and any variants thereof involved in the present application are intended to cover non-exclusive inclusion; for example, a process, method, system, product or device including a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent in these processes, methods, products or devices. The terms "connected", "coupled" and the like involved in the present application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "plurality" involved in the present application refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Usually, the character " / " indicates that the objects associated before and after are in an "or" relationship. The terms "first", "second", "third", etc. involved in the present application are only used to distinguish similar objects and do not represent a specific sorting for the objects.

[0036] Most of the current mainstream traffic lights are controlled by dedicated lines. After the wires led out from the control cabinet are concentrated and converged, they are respectively connected to each traffic light at the intersection through buried pipelines to provide power transmission for all traffic lights.

[0037] Figure 1 It is a schematic diagram of a traffic light control circuit in the related art. As Figure 1 shown, in the existing solution, only one switch on the live wire N is used to control the traffic light. When the switch is turned on, the traffic light is lit, and when the switch is turned off, the traffic light is extinguished.

[0038] When there is a connection between the live wire and the neutral wire among the signal lights, once power is supplied and a short circuit is formed, the current surges, instantly blowing the fuse and causing the signal lights to go out. Even if there is poor contact, the large current spikes generated in the circuit are easily detected and sensed, enabling a relatively fast response to faults. When there is a connection between the live wires among the signal lights, the leakage current is small and unstable. The signal lights usually have poor contact, flickering on and off, resulting in an increase in false judgments and false alarms. Complex fault detection needs to be carried out by means of the calculation and analysis of the processor. The entire fault response process is also relatively slow. During the detection period, the signal lights that were originally off may be accidentally lit, which is likely to affect traffic.

[0039] Therefore, in such a complex wiring situation, crosstalk between wires is inevitable. The connection of wires is likely to cause false triggering of the signal lights, with lights that should not be on being lit and lights that should not be off being turned off. Moreover, such faults are difficult to troubleshoot. If not responded to and resolved in a timely manner, it will also affect traffic.

[0040] In this embodiment, a traffic signal control circuit is provided. Figure 2 It is a schematic diagram of the traffic signal control circuit in this embodiment, as Figure 2 shown. The traffic signal control circuit includes: an intersection signal light system (not shown in the figure), a control module (not shown in the figure), and a switch module corresponding to each signal light in the signal light group of the intersection signal light system; each signal light is connected to the live wire L and the neutral wire N through the switch module; the switch module includes a first switch and a second switch. The first switch and the fuse fn are arranged on the live wire, and the second switch is arranged on the neutral wire.

[0041] Each switch module is connected to the control module and is used to control the opening or closing of the first switch and the second switch under the control of the first timing of the control module. When there is a connection between the live wires among the signal lights, the corresponding signal lights are normally lit or extinguished; when there is a connection between the live wire and the neutral wire among the signal lights, the fuse blows to quickly cut off the circuit to respond to the crosstalk fault between wires.

[0042] Among them, the intersection signal light system includes signal light groups in different directions at the intersection. Each signal light group includes three signal lights: red, green, and yellow. Each signal light has a corresponding switch module and is connected to the live wire L and the neutral wire N through the corresponding switch module. The switch module includes a first switch and a second switch. The first switch and the second switch are respectively arranged on the live wire and the neutral wire. Each signal light is jointly controlled by the two switches in the corresponding switch module to achieve lighting and extinguishing. When the signal light is lit, the first switch in the corresponding switch module is open and the second switch is closed; when the signal light is extinguished, the first switch in the corresponding switch module is closed and the second switch is open. When the first switch is closed, the second switch connects to the neutral wire. If there is a leakage situation due to crosstalk at this time, the crosstalk leakage will flow into the neutral wire through the second switch.

[0043] Each switch module is connected to a control module, which includes a multi-level controller. The switch module is used to control the first switch and the second switch to turn on or off under the control of the first timing of the control module, so as to light up or extinguish the corresponding signal light and present different signal light states of the signal light group. The first timing is the timing in which the controller in the control module controls the first switch and the second switch to act in a certain timing.

[0044] When the live wire and the neutral wire are overlapped between the signal lights, the original signal light status is not affected, and the corresponding signal light is lit or extinguished normally; when the live wire and the neutral wire are overlapped between the signal lights, the fuse burns out to quickly cut off the loop response line crosstalk fault, which not only responds in time but also makes subsequent fault detection easier.

[0045] Figure 3 Schematic diagram of overlap between signal lights in this embodiment, such as Figure 3 As shown, from top to bottom are the first signal light group, the second signal light group and the third signal light group. When overlap occurs between signal lights in a signal light group, for example, the originally lit red light in the first signal light group overlaps with the originally extinguished green light, it is actually the live wire and the neutral wire that overlap. At the moment of overlap, the current surges, the fuse burns out, and the circuit is cut off. The red light goes out, and the green light does not light up. When overlap occurs between signal lights in multiple signal light groups, for example, the originally lit yellow light in the second signal light group overlaps with the originally extinguished red light in the third signal light group, it is actually the live wire and the neutral wire that overlap. The red light is not affected, and the yellow light is short-circuited and extinguished. When a signal light and the neutral wire overlap, for example, the originally lit green light in the third signal light group overlaps with the neutral wire, the green light is quickly short-circuited and extinguished.

[0046] In this way, the original related technology Figure 1 The overlap fault of the live wire and the live wire between the signal lights can be converted into the overlap fault of the live wire and the neutral wire in this embodiment. Therefore, when the live wire and the neutral wire overlap between the signal lights, the fuse on the live wire burns out and quickly cuts off the circuit response, and quickly extinguishes the originally lit signal lights without accidentally lighting other signal lights. Figure 3 Taking the case where the red light in the first signal light group and the yellow light in the second signal light group overlap, the two lights remain on, so even if there is a live wire overlap between the signal lights, it will not affect the state of the signal lights, and the signal lights will light up or go out normally.

[0047] Through the above traffic signal control circuit, each signal lamp is controlled to turn on and off by the cooperation of two switches respectively arranged on the live wire and the neutral wire. When there is a connection between the live wire and the neutral wire among the signal lamps, the fuse on the live wire burns out to quickly cut off the loop and respond to the crosstalk fault between the lines. When there is a connection between the live wires among the signal lamps, it will not affect the state of the signal lamps, and the corresponding signal lamps will be normally lit or extinguished, and there will be no situation where the signal lamps are mislit, solving the problem of the failure to promptly respond to the crosstalk between the lines and affecting traffic.

[0048] In some of these embodiments, the first timing control of the control module includes:

[0049] When the second switch in the switch module is first turned off and then the first switch is turned on, the corresponding signal lamp is lit;

[0050] When the first switch in the switch module is first turned off and then the second switch is turned on, the corresponding signal lamp is extinguished.

[0051] Specifically, the first timing control can be specifically implemented by a secondary controller in the control module. The secondary controller includes but is not limited to a single-chip microcomputer, etc. The single-chip microcomputer outputs a TTL (Transistor-Transistor Logic) weak electrical signal to control the opening and closing of the first switch and the second switch. The control of the first timing is specifically to first turn off the second switch and then turn on the first switch to control the signal lamp to light up; first turn off the first switch and then turn on the second switch to control the signal lamp to extinguish. Among them, the action times of the first switch and the second switch are also set in the first timing.

[0052] Through the first timing control of the control module in this embodiment, the on and off of the signal lamps can be controlled through the switch module, and the sequential actions of the first switch and the second switch can also avoid short circuits.

[0053] In some of these embodiments, the control module is used to control the signal lamp states of each signal lamp group in the intersection signal lamp system in a second timing.

[0054] Specifically, the control module may further include a main controller. The main controller is responsible for calculating the signal control logic sequence in the intersection signal lamp system, such as the lighting duration and extinguishing duration of each signal lamp, and further obtaining the second timing for controlling the signal lamp states of each signal lamp group according to the signal control logic sequence. Under the control of the main controller for each signal lamp group in the entire intersection signal lamp system, the on and off of each signal lamp in the signal lamp group is further controlled by the first timing of the secondary controller.

[0055] Through the second timing of the control module in this embodiment, a higher-level control of each signal lamp group in the entire intersection signal lamp system can be achieved, ensuring traffic order.

[0056] In some of these embodiments, the first switch and the second switch are thyristor switches or relay switches.

[0057] Specifically, a thyristor is a semiconductor device that regulates its on and off states by controlling the voltage at its gate. When it is on, current can flow freely between the gate and the cathode, and when it is off, the current is cut off. It has advantages such as precise control and fast response speed. A relay is an electromagnetic switch component composed of a coil and a set of contacts. When the coil is energized, the generated magnetic field closes the contacts, thus connecting the circuit; when the power is off, the contacts open, cutting off the circuit.

[0058] However, after the thyristor is turned off, there may be a large amount of leakage current due to different loads. For the control circuit in Figure 1 , when selecting a thyristor switch, the turn-off leakage of the thyristor may cause misjudgment in the fault detection circuit, and even mis-light the signal lamp when the current is large, which will also affect traffic.

[0059] In this embodiment, if a thyristor switch is used, when the first switch has turn-off leakage, the second switch absorbs the leakage of the first switch. Figure 4 is a schematic diagram of the turn-off leakage situation of the switch in this embodiment. As Figure 4 shown, when turning off the red light and the yellow light, first turn off the first switch on the live wire, and then turn on the second switch on the neutral wire. If the first switch has turn-off leakage, the leakage is absorbed by the second switch and will not flow into the wire and the load.

[0060] Through the design of the two switches in the switch module of this embodiment, even if the thyristor switch used has turn-off leakage, the second switch on the neutral wire will absorb the leakage of the first switch on the live wire, so that the leakage will not flow into the load, and thus the signal lamp will not be mis-lit.

[0061] In some of these embodiments, Figure 5 is a schematic circuit diagram of the first switch in this embodiment. As Figure 5 shown, the circuit includes a resistor, a driver, a thyristor, a capacitor, a fuse, a variable resistor, etc.

[0062] Pin 1 of driver U10 is connected to the control signal L_Relay of the control module through resistor R129 (such as the TTL weak electrical signal of a single-chip microcomputer). Pin 2 of driver U10 is grounded. Pin 6 is connected to the live wire terminal L_IN before the switch through resistor R827 and fuses J19 and J20. Pin 4 is connected to the live wire terminal Relay_L after the switch through resistor R828. Among them, the fuse can be a snap-in fuse. Adjustable resistor RV42 is connected in parallel between the live wire terminal L_IN and the live wire terminal Relay_L. Resistor R825 and capacitor C37 are connected in series and then in parallel between the live wire terminal L_IN and the live wire terminal Relay_L. Pin 1 of thyristor Q31 is connected between resistor R828 and the live wire terminal Relay_L. Pin 2 of thyristor Q31 is connected between resistor R827 and the live wire terminal L_IN. Pin 3 of thyristor Q31 is connected to pin 4 of driver U10.

[0063] Among them, the rated current of the signal lamp is generally about 20 mA. Therefore, a 0.5 A fast-blow fuse can be selected to quickly cut off the circuit in case of a short circuit.

[0064] In some of these embodiments, Figure 6 is the circuit schematic diagram of the second switch in this embodiment, as Figure 6 shown. The circuit includes resistors, drivers, thyristors, capacitors, fuses, adjustable resistors, etc.

[0065] Pin 1 of driver U8 is connected to the control signal N_Relay of the control module through resistor R127 (such as the TTL weak electrical signal of a single-chip microcomputer). Pin 2 of driver U8 is grounded. Pin 6 is connected to the live wire terminal Relay_L after the switch through resistor R817. Pin 4 is connected to the neutral wire terminal N_IN before the switch through resistor R818. Adjustable resistor RV40 is connected in parallel between the neutral wire terminal N_IN and the live wire terminal Relay_L. Resistor R816 and capacitor C33 are connected in series and then in parallel between the neutral wire terminal N_IN and the live wire terminal Relay_L. Pin 1 of thyristor Q2 is connected between resistor R818 and the neutral wire terminal N_IN. Pin 2 of thyristor Q31 is connected between resistor R817 and the live wire terminal Relay_L. Pin 3 of thyristor Q31 is connected to pin 4 of driver U8.

[0066] Since the fault of the signal lamp connection in the above embodiments is transformed into the connection of the live wire and the neutral wire, when the live wire and the neutral wire are connected, the fuse burns out to cut off the circuit, which can quickly and obviously find out the location of the fault. There is no need to use a complex detection circuit, and only a simple voltage detection circuit or current detection circuit can be used to achieve fault detection. Even when the fuse does not burn out after the connection occurs, fault detection can also be carried out through voltage detection or current detection to achieve double protection of the circuit.

[0067] In some of these embodiments, the traffic signal control circuit further includes: a voltage detection circuit; the voltage detection circuit is disposed between the neutral line and the live line and is used to detect abnormal signals of the switch module voltage.

[0068] The voltage detection circuit includes an optocoupler voltage detection circuit, a Hall sensor voltage detection circuit, a capacitor charging type voltage detection circuit, and a metering chip voltage detection circuit.

[0069] Specifically, the abnormal signals detected by the voltage detection circuit include two cases: no voltage signal is detected on the signal lamp circuit that should be lit, and a voltage signal is detected on the signal lamp circuit that should be extinguished.

[0070] The optocoupler voltage detection circuit uses an optocoupler (optical coupler) to convert the input electrical signal into an optical signal and then convert the optical signal into an electrical signal for output. The optocoupler internally contains a light-emitting diode and a photosensitive triode (or other photosensitive devices). When the input voltage causes the light-emitting diode to emit light, the photosensitive triode receives the optical signal and generates a corresponding current. By detecting this current or the voltage related to it, the input voltage can be indirectly measured. The optocoupler can achieve electrical isolation between the input and output, effectively avoiding interference and mutual influence between the input-side and output-side circuits, and improving the safety and stability of the circuit.

[0071] The Hall sensor voltage detection circuit is based on the Hall effect. When current passes through a semiconductor wafer placed in a magnetic field, if a voltage is applied in a direction perpendicular to the current and the magnetic field, a Hall voltage proportional to the magnetic field strength and the current magnitude will be generated on both sides of the wafer. By detecting this Hall voltage, physical quantities related to the magnetic field can be measured. In voltage detection, usually the measured voltage is converted into a change in magnetic field strength, and then the Hall voltage is measured to indirectly obtain the measured voltage value.

[0072] The capacitor charging type voltage detection circuit utilizes the charging characteristic of a capacitor. When the capacitor is connected to the measured voltage, the capacitor will be charged within a certain period of time, and the charging current is proportional to the measured voltage. By measuring relevant parameters during the capacitor charging process, such as the charging time, charging current, etc., the value of the measured voltage can be calculated. A common method is to use a constant current source to charge the capacitor and measure the time when the capacitor voltage reaches a certain threshold, and calculate the measured voltage based on the charging time and the constant current source current.

[0073] For the metering chip voltage detection circuit, the metering chip is an integrated circuit specifically used for measuring electrical quantity parameters. It internally integrates functional modules such as analog signal processing, analog-to-digital conversion, and digital signal processing. By converting the measured voltage into a suitable voltage signal through components such as a sampling resistor and inputting it into the metering chip, the chip internally processes and calculates the signal, and finally outputs an accurate voltage measurement value.

[0074] Figure 7 is a schematic diagram of the voltage detection circuit in this embodiment. As Figure 7 shown, the voltage detection circuit includes a resistor, a capacitor, an optocoupler, a diode, a surge protection device, and a rectifier.

[0075] Pin 2 of the rectifier D254 is connected to the live wire terminal Relay_L after the switch through the surge protection device (SPD) D255 and the resistor R782. Pin 3 of the rectifier D254 is connected to the neutral wire terminal N_IN before the switch through the capacitor C793. Pin 1 of the rectifier D254 is connected to pin 1 of the optocoupler U26, and pin 4 of the rectifier D254 is connected to pin 2 of the optocoupler U26. One ends of the capacitor C831, the capacitor C830, and the diode D196 are connected between pin 1 of the rectifier D254 and pin 1 of the optocoupler U26, and the other ends of the capacitor C831, the capacitor C830, and the diode D196 are connected between pin 4 of the rectifier D254 and pin 2 of the optocoupler U26. Pin 4 of the optocoupler U26 is connected to the power supply +3.3V. Pin 3 of the optocoupler U26 is grounded through the resistor R64, and the capacitor C792 is connected in parallel across both ends of the resistor R64. Pin 3 of the optocoupler U26 outputs the detection voltage signal Dect_V.

[0076] In some of these embodiments, the traffic signal control circuit further includes: a current detection circuit; the current detection circuit is disposed between the live wire and the total output for detecting an abnormal signal of the current of the switch module.

[0077] The current detection circuit includes an optocoupler current detection circuit, a Hall sensor current detection circuit, a capacitor charging type current detection circuit, and a metering chip current detection circuit.

[0078] Specifically, the abnormal signals detected by the current detection circuit include two situations: no current signal (square wave signal) is detected on the signal lamp circuit that should be lit, and a current signal is detected on the signal lamp circuit that should be extinguished.

[0079] The optocoupler current detection circuit generally uses a resistor to convert the current into a voltage signal, and then isolates and transmits the signal through an optocoupler. When current flows through the sampling resistor, a voltage drop proportional to the current will be generated across both ends of the resistor. This voltage signal causes the light-emitting diode in the optocoupler to emit light. After the photosensitive device receives the optical signal, it outputs a corresponding electrical signal. By processing and measuring this output electrical signal, the magnitude of the measured current can be indirectly obtained.

[0080] The Hall sensor current detection circuit is based on the Hall effect. When current passes through a wire, a magnetic field is generated. The Hall sensor is placed in this magnetic field, and the Hall element generates a Hall voltage proportional to the magnetic field strength, while the magnetic field strength is proportional to the current in the wire. Therefore, the magnitude of the measured current can be obtained by measuring the Hall voltage. According to different measurement methods, it can be divided into open-loop Hall sensors and closed-loop Hall sensors.

[0081] The capacitor charging type current detection circuit indirectly measures the current by charging a capacitor with the measured current and utilizing the charging characteristics of the capacitor. Within a certain period of time, the voltage change on the capacitor is proportional to the charging current. By measuring the change rate of the capacitor voltage or the time required to reach a certain voltage value, the magnitude of the measured current can be calculated.

[0082] The metering chip current detection circuit integrates a high-precision analog-to-digital converter (ADC), signal processing circuit, etc. inside the metering chip. The measured current is converted into a voltage signal through a sampling resistor and then input into the metering chip. The chip performs digital processing and analysis on this voltage signal and calculates parameters such as the magnitude, effective value, and power of the current using the built-in algorithm.

[0083] Figure 8 is a schematic diagram of the current detection circuit in this embodiment, as Figure 8 shown, the current detection circuit includes resistors, capacitors, optocouplers, and diodes.

[0084] A diode D202 and a diode D204 are connected in series between the live wire terminal Relay_L after the switch and the total output Relay_Out. The cathode of diode D203 is connected to the anode of diode D202, and the anode of diode D203 is connected to the cathode of diode D204. Pin 1 of optocoupler U32 is connected between the live wire terminal Relay_L after the switch and the anode of diode D202 through resistor R819. Pin 2 of optocoupler U32 is connected between diode D204 and the total output Relay_Out. A diode D205 is also connected in parallel between pin 1 and pin 2 of optocoupler U32. Pin 3 of optocoupler U32 is grounded, pin 4 is connected to the power supply +3.3V through resistor R69, and capacitor C797 is connected in parallel across resistor R69. Pin 4 of optocoupler U26 outputs the detection current signal Dect_I.

[0085] In some of these embodiments, when an abnormal signal is detected, the corresponding signal light group is turned off through the control module; and the yellow light in the signal light group is controlled to flash as a warning.

[0086] Specifically, when an abnormal signal is detected, the corresponding signal light group is turned off through the control module, which can achieve double protection in combination with the fuse to prevent the misoperation of the signal lights from affecting traffic. In addition, the yellow lights in the signal light group can be controlled to flash as a warning to remind pedestrians and vehicles that the signal light group is in a fault state and to drive carefully. Specifically, the yellow light flashing warning can be carried out according to different specifications. For example, only the faulty signal light group is controlled to flash the yellow light, all the signal light groups at the intersection are controlled to flash the yellow light, or the yellow light flashes quickly to indicate a fault, etc.

[0087] The following describes and illustrates this embodiment through preferred embodiments.

[0088] As Figure 2 shown, in this embodiment, a traffic signal control circuit is provided. The traffic signal control circuit includes: an intersection signal light system (not shown in the figure), a control module (not shown in the figure), a voltage detection circuit, a current detection circuit, and a switch module corresponding to each signal light in the signal light group of the intersection signal light system; each signal light is connected to the live wire L and the neutral wire N through the switch module; the switch module includes a first switch and a second switch. The first switch and the fuse fn are arranged on the live wire, and the second switch is arranged on the neutral wire.

[0089] Each switch module is connected to the control module and is used to control the opening or closing of the first switch and the second switch under the control of the first timing of the control module. When there is a connection between the live wires of the signal lights, the corresponding signal lights are normally lit or extinguished; when there is a connection between the live wire and the neutral wire of the signal lights, the fuse blows to quickly cut off the circuit to respond to the line-to-line crosstalk fault.

[0090] Among them, the intersection signal light system includes signal light groups in different directions at the intersection. Each signal light group includes three signal lights: red, green, and yellow. Each signal light has a corresponding switch module and is connected to the live wire L and the neutral wire N through the corresponding switch module. The switch module includes a first switch and a second switch. The first switch and the second switch are respectively arranged on the live wire and the neutral wire. Each signal light is jointly controlled by the two switches in the corresponding switch module to achieve lighting and extinguishing. When the signal light is lit, the first switch in the corresponding switch module is open and the second switch is closed; when the signal light is extinguished, the first switch in the corresponding switch module is closed and the second switch is open. When the first switch is closed, the second switch connects to the neutral wire. If there is a leakage situation due to line-to-line crosstalk at this time, the crosstalk leakage will flow into the neutral wire through the second switch.

[0091] Each switch module is connected to the control module, which includes a multi-level controller. The switch module is used to control the first switch and the second switch to open or close under the control of the first timing of the control module to light up or extinguish the corresponding signal light and present different signal light states of the signal light group. The first switch and the second switch are thyristor switches. The first timing control includes: first closing the second switch in the switch module, and then opening the first switch to light up the corresponding signal light; first closing the first switch in the switch module, and then opening the second switch to extinguish the corresponding signal light. The control module can also include a main controller. Under the control of the main controller to each signal light group of the entire intersection signal light system with the second timing, the first timing of the secondary controller is further used to control the on and off of each signal light in the signal light group.

[0092] When the live wire and the neutral wire are overlapped between the signal lights, the original signal light status is not affected, and the corresponding signal light is lit or extinguished normally; when the live wire and the neutral wire are overlapped between the signal lights, the fuse burns out to quickly cut off the loop response line crosstalk fault, which not only responds in time but also makes subsequent fault detection easier.

[0093] like Figure 4 As shown, when turning off the red and yellow lights, first turn off the first switch on the live wire, and then turn on the second switch on the neutral wire. If the first switch has leakage when it is turned off, the leakage will be absorbed by the second switch and will not flow into the wires and loads, which can solve the problem of thyristor leakage when it is turned off.

[0094] like Figure 5 As shown in the circuit diagram of the first switch, the circuit includes a resistor, a driver, a thyristor, a capacitor, a fuse, an adjustable resistor, etc.

[0095] Pin 1 of the driver U10 is connected to the control signal L_Relay (such as the TTL weak current signal of the single-chip microcomputer) of the control module through the resistor R129, pin 2 of the driver U10 is grounded, pin 6 is connected to the live terminal L_IN before the switch through the resistor R827 and the fuses J19 and J20, and pin 4 is connected to the live terminal Relay_L after the switch through the resistor R828. Among them, the fuse can be a snap-on fuse. The adjustable resistor RV42 is connected in parallel between the live terminal L_IN and the live terminal Relay_L, and the resistor R825 and the capacitor C37 are connected in series and then connected in parallel between the live terminal L_IN and the live terminal Relay_L. Pin 1 of the thyristor Q31 is connected between the resistor R828 and the live terminal Relay_L, pin 2 of the thyristor Q31 is connected between the resistor R827 and the live terminal L_IN, and pin 3 of the thyristor Q31 is connected to pin 4 of the driver U10.

[0096] like Figure 6As shown in the circuit schematic diagram of the second switch, the circuit includes a resistor, a driver, a thyristor, a capacitor, a fuse, a variable resistor, etc.

[0097] Pin 1 of driver U8 is connected to the control signal N_Relay of the control module (such as the TTL weak electrical signal of a single-chip microcomputer) through resistor R127. Pin 2 of driver U8 is grounded. Pin 6 is connected to the live wire terminal Relay_L after the switch through resistor R817. Pin 4 is connected to the neutral wire terminal N_IN before the switch through resistor R818. Variable resistor RV40 is connected in parallel between the neutral wire terminal N_IN and the live wire terminal Relay_L. Resistor R816 and capacitor C33 are connected in series and then connected in parallel between the neutral wire terminal N_IN and the live wire terminal Relay_L. Pin 1 of thyristor Q2 is connected between resistor R818 and the neutral wire terminal N_IN. Pin 2 of thyristor Q31 is connected between resistor R817 and the live wire terminal Relay_L. Pin 3 of thyristor Q31 is connected to pin 4 of driver U8.

[0098] In the above embodiments, the fault of the signal lamp connection is converted into the connection of the live wire and the neutral wire. When the live wire and the neutral wire are connected, the fuse is burned out to cut off the circuit, which can quickly and obviously find out the location of the fault. There is no need to use a complex detection circuit, and only a simple voltage detection circuit or current detection circuit can realize the fault detection. Even when the fuse is not burned out after the connection occurs, the fault can also be detected through voltage detection or current detection, realizing double protection of the circuit.

[0099] The voltage detection circuit is arranged between the neutral wire and the live wire and is used to detect the abnormal signal of the switch module voltage; the current detection circuit is arranged between the live wire and the total output and is used to detect the abnormal signal of the switch module current. When an abnormal signal is detected, the corresponding signal lamp group is turned off through the control module; and the yellow lamp in the signal lamp group is controlled to flash for warning.

[0100] It should be understood that the specific embodiments described here are only used to explain this application, rather than to limit it. According to the embodiments provided in this application, all other embodiments obtained by those of ordinary skill in the art without creative work belong to the protection scope of this application.

[0101] Obviously, the drawings are only some examples or embodiments of this application. For those of ordinary skill in the art, this application can also be applied to other similar situations according to these drawings without creative work. In addition, it can be understood that although the work done during the development process may be complex and time-consuming, for those of ordinary skill in the art, some design, manufacturing or production changes based on the technical content disclosed in this application are only conventional technical means and should not be regarded as insufficient disclosure of this application.

[0102] As used in this application, the term "embodiment" means that the specific features, structures, or characteristics described in connection with an embodiment may be included in at least one embodiment of this application. The phrase appears at various locations in the specification and does not necessarily mean the same embodiment, nor does it mean being independent or alternative to other embodiments and mutually exclusive. Those of ordinary skill in the art can clearly or implicitly understand that the embodiments described in this application can be combined with other embodiments without conflict.

[0103] The above-described embodiments merely represent several implementation manners of this application. Their descriptions are relatively specific and detailed, but should not be construed as limiting the scope of patent protection. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can still be made, and these all fall within the protection scope of this application. Therefore, the protection scope of this application shall be subject to the appended claims.

Claims

1. A traffic signal control circuit, characterized in that, Including: An intersection signal lamp system, a control module, and a switch module corresponding to each signal lamp in the signal lamp group of the intersection signal lamp system; each of the signal lamps is connected to the live wire and the neutral wire through the switch module; The switch module includes a first switch and a second switch. The first switch and the fuse are arranged on the live wire, and the second switch is arranged on the neutral wire; Each of the switch modules is connected to the control module and is used to control the opening or closing of the first switch and the second switch under the control of the first timing of the control module, and to normally light or extinguish the corresponding signal lamp when a live wire-to-live wire connection occurs between the signal lamps; When a live wire-to-neutral wire connection occurs between the signal lamps, the fuse blows to quickly cut off the circuit to respond to the crosstalk fault between the lines.

2. The traffic signal control circuit according to claim 1, characterized in that, The first timing control of the control module includes: When first closing the second switch in the switch module and then opening the first switch, the corresponding signal lamp is lit; When first closing the first switch in the switch module and then opening the second switch, the corresponding signal lamp is extinguished.

3. The traffic signal control circuit according to claim 1, characterized in that, The control module is used to control the signal lamp states of each signal lamp group in the intersection signal lamp system with a second timing.

4. The traffic signal control circuit according to claim 1, characterized in that, The first switch and the second switch are thyristor switches or relay switches.

5. The traffic signal lamp control circuit according to claim 1, wherein When the first switch has a turn-off leakage, the second switch absorbs the leakage of the first switch.

6. The traffic signal control circuit according to claim 1, wherein Further including: A voltage detection circuit; The voltage detection circuit is arranged between the neutral wire and the live wire and is used to detect the abnormal signal of the voltage of the switch module.

7. The traffic signal control circuit according to claim 6, wherein The voltage detection circuit includes an optocoupler voltage detection circuit, a Hall sensor voltage detection circuit, a capacitor charging type voltage detection circuit, and a metering chip voltage detection circuit.

8. The traffic signal control circuit according to claim 1, characterized in that Further including: A current detection circuit; The current detection circuit is arranged between the live wire and the total output and is used to detect the abnormal signal of the current of the switch module.

9. The traffic signal control circuit according to claim 8, characterized in that, The current detection circuit includes an optocoupler current detection circuit, a Hall sensor current detection circuit, a capacitor charging type current detection circuit, and a metering chip current detection circuit.

10. The traffic signal lamp control circuit according to any one of claims 6 to 9, wherein When the abnormal signal is detected, the corresponding signal lamp group is turned off through the control module; and the yellow lamp in the signal lamp group is controlled to flash for warning.

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