CN101925216B - LED street lamp - Google Patents

Abstract

The present invention discloses an LED street lamp, including an LED light source and a power supply, wherein the power supply includes an input filter circuit, a rectifier circuit, a high-frequency control circuit, an output rectifier filter circuit and a detection control circuit, wherein a constant current control circuit is connected between the output end of the output rectifier filter circuit and the detection control circuit; and a power factor adjustment circuit is connected between the output end of the rectifier circuit and the high-frequency control circuit. The product adopts a high-frequency switching constant current power supply, the power factor of which is as high as 0.96 or more, the power utilization rate is high, and lightning strike, overcurrent, overvoltage, and temperature rise protection are also provided; the light source is a 60W LED lamp, the LED lamp has low power consumption, a service life of more than 10 years, and the light source does not need to be replaced for life, while the traditional street lamp is replaced once, saving maintenance costs.

Description

A kind of LED street light

technical field

The invention relates to a street lamp, in particular to an LED street lamp using a high-frequency switch constant-current waterproof power supply.

Background technique

At present, most of the street lamps installed on highways, urban roads, primary/secondary arterial roads, schools, hospitals, and housing estates are high-pressure sodium lamps. The lifespan of the high-pressure sodium lamps circulating in the market today can reach 15,000-20,000 hours under the standard voltage working environment, but due to the large fluctuations in the working voltage relative to the standard voltage, the actual lifespan of the light source is less than 6,000 hours (about 1.5 years). , The average service life of the ballast is about 2.5-3 years, and the service life is relatively short, and the installation and maintenance costs and operating power consumption costs of replacing the sodium lamp light source, ballast and other components are relatively high, which is not energy-saving enough.

Contents of the invention

In view of the above problems, the present invention provides an LED street lamp with long service life, low installation and maintenance cost, and low operation power consumption cost, and adopts a high-frequency switching constant current power supply.

The technical scheme that the present invention adopts for solving its technical problem is:

An LED street lamp includes an LED light source and a power supply. The power supply includes an input filter circuit, a rectification circuit, a high-frequency control circuit, an output rectification filter circuit, and a detection control circuit. The output end of the output rectification filter circuit is connected to the detection control circuit. There is a constant current control circuit; a power factor adjustment circuit is connected between the output terminal of the rectification circuit and the high frequency control circuit.

The beneficial effect of the present invention is: the present invention adopts the high-frequency switching constant current power supply, the power factor of the power supply is as high as 0.96 or more, the utilization rate of electric energy is high, and it is also equipped with lightning strike, overcurrent, overvoltage, and temperature rise protection; the lamp source is 60W LED lights, LED lights do not contain harmful elements such as mercury and sodium, will not pollute the environment, and the color rendering is better than traditional sodium lights, which can create a more comfortable visual environment and improve safety. In addition, LED power consumption is low, And the high-frequency switch constant current waterproof power supply can continuously and stably supply power to the LED lights, so that the LED lights can be used continuously for 50,000 hours, and the service life is more than 10 years. There is no need to replace the light source for life, and the traditional street lamps need to be replaced once, saving maintenance costs.

Description of drawings

The present invention will be further described below in conjunction with accompanying drawing and specific embodiment:

Fig. 1 is the principle block diagram of the power supply of the embodiment of the present invention;

Fig. 2 is the circuit principle diagram of the power supply of the embodiment of the present invention

Fig. 3 is a connection diagram of the embodiment of the present invention.

Detailed ways

With reference to Fig. 1, a kind of LED street lamp, comprises LED light source 2 and power supply 1, and this power supply is the high-frequency switching constant current power supply including input filter circuit 11, rectification circuit 12, high-frequency control circuit 13, output rectification filter circuit 14 and detection The control circuit 15 is characterized in that: a constant current control circuit 16 is connected between the output end of the output rectification filter circuit 14 and the detection control circuit 15; and power factor adjustment circuit 17.

Further referring to Fig. 2, the power supply circuit of the inventive street lamp is directly connected to the input filter circuit 11 by the 220V commercial power through the fuse F1. The other end is connected to one end of capacitor CY2 and then grounded, and the other end of capacitor CY2 is connected to pin 4 of reactance L1. This circuit filters the clutter existing in the power grid and prevents the clutter generated by the machine from being fed back to the public power grid. The filtered power is then input to the rectifier circuit 12; in addition, lightning protection and overvoltage protection resistors R1 and R2 are connected to pins 1 and 3 of the reactance L1, and the resistors R1 and R2 are connected in parallel.

The power supply is filtered and input to the rectification circuit 12 composed of 4 diode D1 bridge stacks, which directly rectifies the alternating current in the power grid into a relatively smooth direct current; in addition, a power factor adjustment circuit 17 is connected after the rectification circuit 12, and the power factor adjustment The circuit 17 is composed of diodes D2, D3, D4 and capacitors C2 and C3; the diode D2 is connected in series with the capacitor C3 to the output end of the rectifier circuit 12, and the diode D4 is connected in series with the capacitor C2 and connected to both ends of the diode D2 and the capacitor C3. The diode D3 is bridged between the capacitor C2 and the diode D2; the current in the circuit passes through the forward and reverse conduction principle of the diodes D2, D3, D4 and the principle of discharging the capacitors C2 and C3, modulating the input current and charging the capacitors C2 and C3 In the rectification period, the charging is completed several times, which reduces the energy concentration caused by one charge, reduces the peak value of the input current, improves the harmonics of the input current, widens the conduction angle, and improves the power factor. Due to the existence of the energy storage smoothing capacitor in the traditional rectifier circuit 2, the input current produces a spike, and the conduction angle of the current is very small, resulting in the disadvantages of low power factor and high harmonics.

The power supply is input to the high-frequency control circuit 13 composed of power adapter J1, switch tube Q1, and transformers HB1 and HB2 through the power factor adjustment circuit 17. This circuit inverts the input DC power into AC power, and then passes through the output rectification filter circuit 14 outputs.

A detection control circuit 15 is connected between the high-frequency control circuit 3 and the output rectification filter circuit 14. The circuit is composed of photocoupler U1, thyristor U2 and other components. comparison, and then control the inverter in the high-frequency control circuit 13 to change its frequency or pulse width to achieve stable output.

A constant current control circuit 16 is connected between the output rectification filter circuit 4 and the detection control circuit 15, and the circuit is composed of a triode Q2, a capacitor C12, and resistors R11 and R12. The collector of the triode Q2 is connected to the detection control circuit 15, and the emitter Connect to the output end of the circuit through resistor R11, the base is connected to the output end of the circuit through capacitor C12 and resistor R12, and the capacitor C12 and resistor R12 are connected in parallel; the current supplied by this circuit to the load LED is consistent, and the output is constant. , the control method adopted is to connect a small resistance resistor R11 in series with the negative electrode of the rectifier output, so that a voltage drop is generated at both ends of the resistor R11, and the transistor Q2 is controlled by the resistor R12 to the base of the transistor Q2, so that the photocoupler U1 The control terminal maintains a stable voltage value and plays a role in controlling the output current.

The power factor of the high-frequency switching constant current power supply manufactured by the above scheme is greater than 0.95, the efficiency is as high as 92%, and the harmonic distortion of the input current waveform is less than 5%, so the output current and voltage are very stable, and it can be used in LED street lamps. to great effect.

The above is a specific description of the preferred implementation of the present invention, but the invention is not limited to the described embodiments, and those skilled in the art can also make various equivalent deformations or replacements without violating the spirit of the present invention. These equivalent modifications or replacements are all within the scope defined by the claims of the present application.

Claims (2)

1. LED street lamp, comprise LED lamp source (2) and power supply (1), power supply (1) comprises input filter circuit (11), rectification circuit (12), high frequency control circuit (13), output rectifier and filter (14) and detects control circuit (15), it is characterized in that: be connected with constant-current control circuit (16) between described output rectifier and filter (14) output and the detection control circuit (15); Be connected with power factor regulation circuit (17) between described rectification circuit (12) output and the high frequency control circuit (13); Wherein, described power factor regulation circuit (17) is comprised of diode D2, D3, D4 and capacitor C 2, C3; Diode D2 and the output that is connected to rectification circuit (12) after capacitor C 3 is connected, diode D4 be attempted by diode D2 and capacitor C 3 two ends after capacitor C 2 is connected, diode D3 bridge joint is between capacitor C 2 and diode D2; Described constant-current control circuit (16) is comprised of triode Q2, capacitor C 12 and resistance R 11, resistance R 12; The collector electrode of triode Q2 is connected to and detects control circuit (15), and emitter is connected to resistance R 12 by resistance R 11, and base stage then is connected to the output of output rectifier and filter (14) by resistance R 12, and capacitor C 12 is connected in parallel on resistance R 12 two ends.

2. a kind of LED street lamp according to claim 1, it is characterized in that: described input filter circuit (11) is comprised of capacitor C Y1, CY2 and reactance L1, the end of capacitor C Y1 links to each other with the output plus terminal of reactance L1, ground connection after the other end links to each other with the end of capacitor C Y2, the other end of capacitor C Y2 links to each other with the output negative terminal of reactance L1; Lightning protection and overvoltage protection resistance R 1, R2 are connected in parallel on the input of reactance L1.

Images