Stepless dimming LED street lamp intelligent control system

Abstract

The utility model provides an intelligent control system for a stepless dimming LED street lamp. The intelligent control system comprises a remote monitoring unit, a control chip, a direct current power supply, an ambient light detection circuit, a voltage regulation circuit, an LED constant current control circuit and an LED street lamp LED1, the direct-current power supply comprises a rectifying circuit, a front-end circuit and a switch control circuit; actual brightness requirements can be ensured, so that traffic safety is ensured, energy can be saved, the adaptive capacity is high, and the system can adapt to various traffic road sections; and moreover, the working state of each single lamp can be monitored in real time, and early warning can be carried out on the single lamp which does not work, so that maintenance and inspection are facilitated.

Description

Technical Field

[0001] The utility model relates to a street lamp control system, in particular to an intelligent control system for an infinitely dimmable LED street lamp. Background Art

[0002] Due to its own characteristics, such as stability and long service life, LEDs are widely used in traffic street lamps. In existing traffic street lamps, LED street lamps are all controlled by a cluster control method. This method has the following defects: Although cluster control can work according to the set working requirements, that is, work according to the set brightness, this method has poor adaptability and flexibility. Because in traffic sections, the ambient light in different sections is different. At noon, this gap is relatively small because the ambient light brightness is strong at this time and can meet the traffic lighting needs. However, when evening comes, due to the decrease in ambient light and the influence of tall green plants on the roadside, the difference in the actual ambient light of LED street lamps at different section positions is relatively large. If the same brightness is still used for lighting, at this time, if the brightness is too large, it will cause waste of resources, and if the brightness is too small, it cannot meet the lighting needs of some sections.

[0003] Therefore, in order to solve the above technical problems, it is urgent to propose a new technical means. Summary of the Utility Model

[0004] In view of this, the purpose of the utility model is to provide an intelligent control system for an infinitely dimmable LED street lamp, which can adaptively adjust its own lighting brightness according to the actual ambient brightness of the street lamp, can ensure the actual brightness demand, thus ensuring traffic safety, and can also save energy, has strong adaptability, and can adapt to various traffic sections; and can also monitor the working state of each single lamp in real time and give an early warning to the non-working single lamp, thus facilitating maintenance and inspection.

[0005] An intelligent control system for an infinitely dimmable LED street lamp provided by the utility model includes a remote monitoring unit, a control chip, a DC power supply, an ambient light detection circuit, a voltage adjustment circuit, an LED constant current control circuit, and an LED street lamp LED1;

[0006] The DC power supply includes a rectification circuit, a pre-stage circuit, and a switch control circuit; the input end of the rectification circuit is connected to the commercial power, the output end of the rectification circuit is connected to the input end of the pre-stage circuit, the output end of the pre-stage circuit is connected to the input end of the switch control circuit, the output end of the switch control circuit is connected to the input end of the voltage adjustment circuit, the output end of the voltage adjustment circuit is connected to the positive electrode of the LED street lamp LED1, and the negative electrode of the LED street lamp LED1 is connected to the input end of the LED constant current control circuit;

[0007] The ambient light detection circuit is used to detect the ambient light state of the current street lamp. The output end of the ambient light detection circuit is connected to the control chip. The control output end of the control chip is connected to the voltage adjustment circuit. The control chip outputs a PWM control signal corresponding to the current ambient light to the voltage adjustment circuit according to the ambient light state, and the voltage adjustment circuit adjusts the output voltage to the LED street lamp LED1 according to the PWM control signal. The control output end of the control chip is connected to the input end of the switch control circuit, and controls the conduction and cut-off of the switch control circuit according to the ambient light state;

[0008] The brightness sensor of the LED street lamp is used to detect the real-time working brightness of the LED street lamp and output it to the control chip. The control chip is communicatively connected to the remote monitoring unit.

[0009] Further, the LED constant current control circuit includes a digital potentiometer RP, a resistor R12, a resistor R14, an operational amplifier U1, a resistor R15, a resistor R17, a resistor R18, a capacitor C6, and an NMOS transistor Q2;

[0010] The positive power supply end of the digital potentiometer RP is connected to the power supply VCC. The negative power supply end of the digital potentiometer RP is connected to one end of the resistor R14 through the resistor R12. The control input end of the digital potentiometer RP is connected to the control output end of the control chip. The other end of the resistor R14 is grounded. The non-inverting input end of the operational amplifier U1 is connected to the common connection point between the resistor R12 and the resistor R14. The inverting input end of the operational amplifier U1 is connected to the source electrode of the NMOS transistor Q2 through the resistor R17. The source electrode of the NMOS transistor Q2 is grounded through the resistor R18. The inverting input end of the operational amplifier U1 is grounded through the capacitor C6. The output end of the operational amplifier U1 is connected to the gate electrode of the NMOS transistor Q2 through the resistor R15. The drain electrode of the NMOS transistor Q2 is connected to the negative electrode of the LED street lamp LED1.

[0011] Further, the LED constant current control circuit further includes a temperature compensation circuit. The temperature compensation circuit includes a resistor R9, a thermistor NTC, a resistor R10, a resistor R13, a resistor R16, a resistor R19, a capacitor C7, and an NMOS transistor Q3;

[0012] One end of the resistor R9 is connected to the power supply VCC. The other end of the resistor R9 is connected to one end of the thermistor NTC through the resistor R10. The other end of the thermistor NTC is grounded. The common connection point between the resistor R9 and the resistor R10 is connected to the drain of the NMOS transistor Q3. The gate of the NMOS transistor Q3 is connected to the common connection point between the thermistor NTC and the resistor R10 through the resistor R13. The gate of the NMOS transistor Q3 is grounded through the capacitor C7. The source of the NMOS transistor Q3 is connected to one end of the resistor R16. The other end of the resistor R16 is grounded through the resistor R19. The common connection point between the resistor R16 and the resistor R19 is connected to the gate of the NMOS transistor Q2 as the output end of the temperature compensation circuit.

[0013] Further, the ambient light detection circuit includes a resistor R22, a resistor R20, a resistor R21, a photoresistor PR, and an operational amplifier U2;

[0014] One end of the resistor R22 is connected to the power supply VCC. The other end of the resistor R22 is grounded through the photoresistor PR. The common connection point between the resistor R22 and the photoresistor PR is connected to the non-inverting input end of the operational amplifier U2 through the resistor R20. The inverting input end of the operational amplifier U2 is connected to the reference voltage Vref. The non-inverting input end of the operational amplifier U2 is connected to the output end of the operational amplifier U2 through the resistor R21. The output end of the operational amplifier U2 is connected to the control chip as the output end of the ambient light detection circuit.

[0015] Further, the preamplifier circuit includes an R23, a capacitor C8, and an operational amplifier U3;

[0016] One end of the resistor R23 is connected to the positive output end of the rectifier circuit. The other end of the resistor R23 is grounded through the capacitor C8. The common connection point between the resistor R23 and the capacitor C8 is connected to the non-inverting input end of the operational amplifier U3. The inverting input end of the operational amplifier U3 is directly connected to the output end of the operational amplifier U3. The output end of the operational amplifier U3 is used as the output end of the preamplifier circuit.

[0017] Further, the switch control circuit includes an optocoupler OC1, a resistor R24, a diode D5, and a triode Q4;

[0018] The collector of the photosensitive triode of the optocoupler OC1 is used as the input end of the switch control circuit. The emitter of the photosensitive triode of the optocoupler OC1 is used as the output end of the switch control circuit. One end of the resistor R24 is connected to the output end of the preamplifier circuit. The other end of the resistor R24 is connected to the collector of the triode Q4. The emitter of the triode Q4 is connected to the positive electrode of the light-emitting diode of the optocoupler OC1. The negative electrode of the light-emitting diode of the optocoupler OC1 is grounded. The base of the triode Q4 is connected to the negative electrode of the diode D5. The positive electrode of the diode D5 is connected to the control chip as the control input end of the switch control circuit.

[0019] Further, the monitoring unit includes a monitoring host, a touch display, and a timing circuit; the monitoring host is communicatively connected to the control chip, the touch display is connected to the monitoring host, and the timing circuit is connected to the monitoring host.

[0020] Further, a power supply circuit is further included. The power supply circuit includes a first voltage stabilization circuit and a second voltage stabilization circuit. The input end of the first voltage stabilization circuit is connected to the output end of the pre-stage circuit, the input end of the second voltage stabilization circuit is connected to the output end of the first voltage stabilization circuit, the first voltage stabilization circuit also provides the power supply VCC, and the second voltage stabilization circuit supplies power to the control chip;

[0021] Among them, the first voltage stabilization circuit is the SY8501 chip and its peripheral circuits;

[0022] The second voltage stabilization circuit is the MP2451 chip and its peripheral circuits.

[0023] Further, the control chip is the MT32L083 chip.

[0024] The beneficial effects of the present utility model are as follows: It can adaptively adjust its own illumination brightness according to the actual ambient brightness of the street lamp, can ensure the actual brightness requirement, thereby ensuring traffic safety, and can also save energy, has strong adaptability, and can adapt to various traffic sections; moreover, it can also monitor the working states of each single lamp in real time and give early warnings to the non-working single lamps, which is beneficial for maintenance and inspection. Description of the Drawings

[0025] The following further describes the present utility model in conjunction with the drawings and embodiments:

[0026] Figure 1 It is a schematic structural diagram of the present utility model.

[0027] Figure 2 It is a schematic diagram of the LED constant current control circuit of the present utility model.

[0028] Figure 3 It is a schematic diagram of the voltage adjustment circuit and the DC power supply of the present utility model.

[0029] Figure 4 It is a schematic diagram of the ambient light detection circuit of the present utility model. Detailed Embodiment

[0030] The following further elaborates on the present utility model in detail:

[0031] An intelligent control system for a non-polar dimming LED street lamp provided by the present utility model includes a remote monitoring unit, a control chip, a DC power supply, an ambient light detection circuit, a voltage adjustment circuit, an LED constant current control circuit, and an LED street lamp LED1;

[0032] The DC power supply includes a rectifier circuit, a pre-stage circuit, and a switch control circuit; the input end of the rectifier circuit is connected to the mains power supply, the output end of the rectifier circuit is connected to the input end of the pre-stage circuit, the output end of the pre-stage circuit is connected to the input end of the switch control circuit, the output end of the switch control circuit is connected to the input end of the voltage adjustment circuit, the output end of the voltage adjustment circuit is connected to the positive electrode of the LED street lamp LED1, and the negative electrode of the LED street lamp LED1 is connected to the input end of the LED constant current control circuit; among them, the rectifier circuit adopts a full-bridge rectifier circuit Z1 composed of diodes;

[0033] The ambient light detection circuit is used to detect the ambient light state of the current street lamp. The output end of the ambient light detection circuit is connected to the control chip, and the control output end of the control chip is connected to the voltage adjustment circuit. The control chip outputs a PWM control signal corresponding to the current ambient light to the voltage adjustment circuit according to the ambient light state. The voltage adjustment circuit adjusts the output voltage to the LED street lamp LED1 according to the PWM control signal; the control output end of the control chip is connected to the input end of the switch control circuit, and controls the conduction and cut-off of the switch control circuit according to the ambient light state;

[0034] The LED street lamp brightness sensor is used to detect the real-time working brightness of the LED street lamp and output it to the control chip; the control chip is communicatively connected to the remote monitoring unit.

[0035] Among them, the control chip is the MT32L083 chip. Of course, this chip also has corresponding peripheral circuits, which can be built according to its factory specification sheet and will not be elaborated here. The voltage adjustment circuit is the UC3843 chip and its peripheral circuits. Specifically, as Figure 3 shown, the control chip generates PWM control signals with different duty cycles according to the actual situation of the ambient light, and the voltage adjustment circuit works according to the PWM control signal, so as to realize the stepless adjustment of the working voltage of the LED street lamp.

[0036] The ambient light detection circuit is used to detect the ambient light state of the current street lamp. On the one hand, when the ambient light is insufficient, the control chip controls the switch control circuit to conduct, and sets the duty cycle of the PWM control signal of the output value voltage adjustment circuit according to the ambient light, and sets the current of the LED constant current control circuit, so as to ensure the stable operation of the whole system. Moreover, the control chip feeds back the current real-time ambient light state to the monitoring host, and uploads the actual brightness of the real-time LED street lamp. The monitoring host judges whether the street lamp is faulty according to the state of the ambient light and the actual luminous brightness of the street lamp, which is conducive to timely maintenance. Through the above, it can adaptively adjust its own illumination brightness according to the actual ambient brightness of the street lamp, ensure the actual brightness demand, thus ensuring traffic safety, and can also save energy, with strong adaptability, and can adapt to various traffic sections; moreover, it can also monitor the working state of each single lamp in real time and give early warnings to the non-working single lamps, which is conducive to maintenance.

[0037] In this embodiment, the LED constant current control circuit includes a digital potentiometer RP, a resistor R12, a resistor R14, an operational amplifier U1, a resistor R15, a resistor R17, a resistor R18, a capacitor C6, and an NMOS transistor Q2;

[0038] The positive power supply terminal of the digital potentiometer RP is connected to the power supply VCC. The negative power supply terminal of the digital potentiometer RP is connected to one end of the resistor R14 through the resistor R12. The control input terminal of the digital potentiometer RP is connected to the control output terminal of the control chip. The other end of the resistor R14 is grounded. The non-inverting terminal of the operational amplifier U1 is connected to the common connection point between the resistor R12 and the resistor R14. The inverting terminal of the operational amplifier U1 is connected to the source electrode of the NMOS transistor Q2 through the resistor R17. The source electrode of the NMOS transistor Q2 is grounded through the resistor R18. The inverting terminal of the operational amplifier U1 is grounded through the capacitor C6. The output terminal of the operational amplifier U1 is connected to the gate electrode of the NMOS transistor Q2 through the resistor R15. The drain electrode of the NMOS transistor Q2 is connected to the negative electrode of the LED street lamp LED1. Through the above structure, a constant current circuit is formed. The resistor R18 forms a current detection resistor. Current feedback is carried out through the resistor R17, and then the voltage signals of the non-inverting terminal and the inverting terminal of the operational amplifier U1 are compared and controlled, so that Q2 maintains a stable on state. Different on states of Q2 correspond to different on resistances, so that the working current of LED1 can be adjusted. The control chip obtains the actual working voltage and the required working current of the current LED street lamp LED1 according to the current ambient light state. The actual working voltage is realized by the control chip generating a corresponding PWM signal to control the voltage adjustment circuit, while the working current is adjusted by controlling the resistance value of RP. Thus, the operational amplifier controls Q2 to work in the corresponding on state to form a constant working current. The digital potentiometer RP can use an existing digital potentiometer chip, which will not be elaborated here.

[0039] In this embodiment, the LED constant current control circuit further includes a temperature compensation circuit, and the temperature compensation circuit includes a resistor R9, a thermistor NTC, a resistor R10, a resistor R13, a resistor R16, a resistor R19, a capacitor C7, and an NMOS transistor Q3;

[0040] One end of the resistor R9 is connected to the power supply VCC, the other end of the resistor R9 is connected to one end of the thermistor NTC through the resistor R10, the other end of the thermistor NTC is grounded, the common connection point between the resistor R9 and the resistor R10 is connected to the drain of the NMOS transistor Q3, the gate of the NMOS transistor Q3 is connected to the common connection point between the thermistor NTC and the resistor R10 through the resistor R13, the gate of the NMOS transistor Q3 is grounded through the capacitor C7, the source of the NMOS transistor Q3 is connected to one end of the resistor R16, the other end of the resistor R16 is grounded through the resistor R19, and the common connection point between the resistor R16 and the resistor R19 is used as the output end of the temperature compensation circuit and is connected to the gate of the NMOS transistor Q2. During the operation of the MOS transistor, its on-resistance is greatly affected by temperature. The higher the temperature, the greater its on-resistance. If temperature compensation is not performed, the control signal output by the operational amplifier U1 cannot make Q2 reach the target impedance state. Although feedback can be performed through R17, in fact, when U1 adjusts the output, the actual on-resistance of Q2 is larger than the output value corresponding to U1 at this time, so that the entire constant current circuit is in a repeated adjustment process, the current is not stable, and the working brightness of LED1 is also unstable. Therefore, temperature compensation is required. The thermistor NTC is a negative temperature thermistor, which is arranged near the NMOS transistor to collect the temperature of the NMOS transistor Q2. When the temperature rises, the resistance value of the NTC increases, so that the opening degree of the NMOS transistor becomes larger, the flowing current increases, and then the static operating point of the NMOS transistor Q2 is adjusted, so that the NMOS transistor Q2 can maintain the target current required by LED1 when the temperature rises.

[0041] In this embodiment, the ambient light detection circuit includes a resistor R22, a resistor R20, a resistor R21, a photoresistor PR, and an operational amplifier U2;

[0042] One end of the resistor R22 is connected to the power supply VCC, and the other end of the resistor R22 is grounded through the photoresistor PR. The common connection point between the resistor R22 and the photoresistor PR is connected to the non-inverting input terminal of the operational amplifier U2 through the resistor R20. The inverting input terminal of the operational amplifier U2 is connected to the reference voltage Vref (this reference voltage can be set by a resistor voltage division circuit for the voltage of the power supply VCC, which is a prior art). The non-inverting input terminal of the operational amplifier U2 is connected to the output terminal of the operational amplifier U2 through the resistor R21. The output terminal of the operational amplifier U2 is connected to the control chip as the output terminal of the ambient light detection circuit. Among them, R20, R21, and U2 form a subtraction circuit. When the difference between the non-inverting input terminal and the inverting input terminal of U2 is less than 0, it indicates that the current ambient light brightness meets the lighting requirements, the control chip controls the voltage adjustment circuit not to work, and the triode Q4 is cut off. When the difference between the non-inverting input terminal and the inverting input terminal is greater than 0, it indicates that the ambient light intensity does not meet the requirements. The control chip controls the triode Q4 to conduct, and at the same time, the control chip sets the PWM control signal of the output value voltage adjustment circuit according to the difference, so as to set the output voltage value of the voltage adjustment circuit.

[0043] In this embodiment, the pre-stage circuit includes R23, capacitor C8, and operational amplifier U3;

[0044] One end of the resistor R23 is connected to the positive output terminal of the rectification circuit, the other end of the resistor R23 is grounded through the capacitor C8, the common connection point between the resistor R23 and the capacitor C8 is connected to the non-inverting input terminal of the operational amplifier U3, the inverting input terminal of the operational amplifier U3 is directly connected to the output terminal of the operational amplifier U3, and the output terminal of the operational amplifier U3 is used as the output terminal of the pre-stage circuit. Among them, R23 and capacitor C8 form an RC filter circuit and play a role of voltage limiting and buffering. The operational amplifier U3 forms a voltage follower and uses its high input impedance characteristic for isolation to protect the subsequent circuit.

[0045] In this embodiment, the switch control circuit includes optocoupler OC1, resistor R24, diode D5, and triode Q4;

[0046] The collector of the phototransistor of the optocoupler OC1 is used as the input terminal of the switch control circuit, the emitter of the phototransistor of the optocoupler OC1 is used as the output terminal of the switch control circuit. One end of the resistor R24 is connected to the output terminal of the pre-stage circuit, the other end of the resistor R24 is connected to the collector of the triode Q4, the emitter of the triode Q4 is connected to the positive electrode of the light-emitting diode of the optocoupler OC1, the negative electrode of the light-emitting diode of the optocoupler OC1 is grounded, the base of the triode Q4 is connected to the negative electrode of the diode D5, and the positive electrode of the diode D5 is used as the control input terminal of the switch control circuit and is connected to the control chip. Through the above structure, when the ambient light meets the lighting requirements, the voltage adjustment circuit and the subsequent circuit are disconnected, thereby saving energy.

[0047] In this embodiment, the monitoring unit includes a monitoring host, a touch display, and a timing circuit; the monitoring host is communicatively connected to the control chip, the touch display is connected to the monitoring host, and the timing circuit is connected to the monitoring host. Among them, the timing circuit uses a Beidou or GPS timing circuit to determine whether the actual brightness of the current LED street lamp meets the brightness required for the current time period. The touch display is used to display the distribution status of each LED street lamp (each LED street lamp has a corresponding number. If the control chip of a certain street lamp does not feedback monitoring information after exceeding the set time (if the environmental light is sufficient, the control chip will also feedback the current environmental light status), it indicates that the current street lamp has a fault and is displayed through the touch display).

[0048] In this embodiment, a power supply circuit is further included. The power supply circuit includes a first voltage stabilizing circuit and a second voltage stabilizing circuit. The input end of the first voltage stabilizing circuit is connected to the output end of the pre-stage circuit, the input end of the second voltage stabilizing circuit is connected to the output end of the first voltage stabilizing circuit, the first voltage stabilizing circuit also provides the power supply VCC, and the second voltage stabilizing circuit supplies power to the control chip;

[0049] Among them, the first voltage stabilizing circuit is the SY8501 chip and its peripheral circuit;

[0050] The second voltage stabilizing circuit is the MP2451 chip and its peripheral circuit.

[0051] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the technical solutions of the present invention, and they should all be covered by the scope of the claims of the present invention.

Claims

1. An intelligent control system for stepless dimming LED street lights, characterized by: It includes a remote monitoring unit, a control chip, a DC power supply, an ambient light detection circuit, a voltage adjustment circuit, an LED constant current control circuit, an LED street lamp brightness sensor and an LED street lamp LED1; The DC power supply includes a rectifier circuit, a preamplifier circuit and a switch control circuit; the input end of the rectifier circuit is connected to the mains, the output end of the rectifier circuit is connected to the input end of the preamplifier circuit, the output end of the preamplifier circuit is connected to the input end of the switch control circuit, the output end of the switch control circuit is connected to the input end of the voltage adjustment circuit, the output end of the voltage adjustment circuit is connected to the positive electrode of the LED street lamp LED1, and the negative electrode of the LED street lamp LED1 is connected to the input end of the LED constant current control circuit; The ambient light detection circuit is used to detect the ambient light state of the current street lamp. The output end of the ambient light detection circuit is connected to the control chip. The control output end of the control chip is connected to the voltage adjustment circuit. The control chip outputs a PWM control signal corresponding to the current ambient light to the voltage adjustment circuit according to the ambient light state. The voltage adjustment circuit adjusts the output voltage to the LED street lamp LED1 according to the PWM control signal. The control output end of the control chip is connected to the input end of the switch control circuit, and the switch control circuit is controlled to be turned on and off according to the ambient light state. The LED street lamp brightness sensor is used to detect the real-time working brightness of the LED street lamp and output it to the control chip; the control chip is communicatively connected with the remote monitoring unit.

2. According to claim 1, the stepless dimming LED street lamp intelligent control system is characterized in that: The LED constant current control circuit includes a digital potentiometer RP, a resistor R12, a resistor R14, an operational amplifier U1, a resistor R15, a resistor R17, a resistor R18, a capacitor C6 and an NMOS tube Q2; The positive power terminal of the digital potentiometer RP is connected to the power supply VCC, the negative power terminal of the digital potentiometer RP is connected to one end of the resistor R14 through the resistor R12, the control input terminal of the digital potentiometer RP is connected to the control output terminal of the control chip, the other end of the resistor R14 is grounded, the in-phase terminal of the operational amplifier U1 is connected to the common connection point between the resistor R12 and the resistor R14, the inverting terminal of the operational amplifier U1 is connected to the source of the NMOS tube Q2 through the resistor R17, the source of the NMOS tube Q2 is grounded through the resistor R18, the inverting terminal of the operational amplifier U1 is grounded through the capacitor C6, the output terminal of the operational amplifier U1 is connected to the gate of the NMOS tube Q2 through the resistor R15, and the drain of the NMOS tube Q2 is connected to the negative electrode of the LED street lamp LED1.

3. According to claim 2, the stepless dimming LED street lamp intelligent control system is characterized in that: The LED constant current control circuit also includes a temperature compensation circuit, which includes a resistor R9, a thermistor NTC, a resistor R10, a resistor R13, a resistor R16, a resistor R19, a capacitor C7 and an NMOS tube Q3; One end of the resistor R9 is connected to the power supply VCC, the other end of the resistor R9 is connected to one end of the thermistor NTC through the resistor R10, the other end of the thermistor NTC is grounded, the common connection point between the resistor R9 and the resistor R10 is connected to the drain of the NMOS tube Q3, the gate of the NMOS tube Q3 is connected to the common connection point between the thermistor NTC and the resistor R10 through the resistor R13, the gate of the NMOS tube Q3 is grounded through the capacitor C7, the source of the NMOS tube Q3 is connected to one end of the resistor R16, the other end of the resistor R16 is grounded through the resistor R19, and the common connection point of the resistor R16 and the resistor R19 is connected to the gate of the NMOS tube Q2 as the output end of the temperature compensation circuit.

4. According to claim 3, the stepless dimming LED street lamp intelligent control system is characterized in that: The ambient light detection circuit includes a resistor R22, a resistor R20, a resistor R21, a photoresistor PR and an operational amplifier U2; One end of the resistor R22 is connected to the power supply VCC, the other end of the resistor R22 is grounded through the photoresistor PR, the common connection point between the resistor R22 and the photoresistor PR is connected to the in-phase end of the operational amplifier U2 through the resistor R20, the inverting end of the operational amplifier U2 is connected to the reference voltage Vref, the in-phase end of the operational amplifier U2 is connected to the output end of the operational amplifier U2 through the resistor R21, and the output end of the operational amplifier U2 is connected to the control chip as the output end of the ambient light detection circuit.

5. According to claim 4, the stepless dimming LED street lamp intelligent control system is characterized in that: The front circuit includes R23, capacitor C8 and operational amplifier U3; One end of the resistor R23 is connected to the positive output end of the rectifier circuit, and the other end of the resistor R23 is grounded through the capacitor C8. The common connection point between the resistor R23 and the capacitor C8 is connected to the in-phase end of the operational amplifier U3. The inverting end of the operational amplifier U3 is directly connected to the output end of the operational amplifier U3, and the output end of the operational amplifier U3 serves as the output end of the preamplifier circuit.

6. According to claim 5, the stepless dimming LED street lamp intelligent control system is characterized in that: The switch control circuit includes an optical coupler OC1, a resistor R24, a diode D5 and a transistor Q4; The collector of the phototransistor of the optocoupler OC1 serves as the input end of the switch control circuit, the emitter of the phototransistor of the optocoupler OC1 serves as the output end of the switch control circuit, one end of the resistor R24 ​​is connected to the output end of the preamplifier circuit, the other end of the resistor R24 ​​is connected to the collector of the transistor Q4, the emitter of the transistor Q4 is connected to the anode of the light-emitting diode of the optocoupler OC1, the cathode of the light-emitting diode of the optocoupler OC1 is grounded, the base of the transistor Q4 is connected to the cathode of the diode D5, and the anode of the diode D5 serves as the control input end of the switch control circuit and is connected to the control chip.

7. According to claim 6, the stepless dimming LED street lamp intelligent control system is characterized in that: The monitoring unit includes a monitoring host, a touch display and a timing circuit; the monitoring host is communicatively connected to the control chip, the touch display is connected to the monitoring host, and the timing circuit is connected to the monitoring host.

8. The stepless dimming LED street lamp intelligent control system according to claim 2, 3 or 4, characterized in that: It also includes a power supply circuit, which includes a first voltage stabilizing circuit and a second voltage stabilizing circuit, wherein the input end of the first voltage stabilizing circuit is connected to the output end of the preamplifier circuit, the input end of the second voltage stabilizing circuit is connected to the output end of the first voltage stabilizing circuit, the first voltage stabilizing circuit also provides a power supply VCC, and the second voltage stabilizing circuit supplies power to the control chip; Among them, the first voltage stabilizing circuit is the SY8501 chip and its peripheral circuits; The second voltage stabilizing circuit is the MP2451 chip and its peripheral circuits.

9. According to claim 1, the stepless dimming LED street lamp intelligent control system is characterized in that: The control chip is MT32L083 chip.

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