CN201210760Y

CN201210760Y - Large power LED lamp soft driving power source comprising over-current protection

Info

Publication number: CN201210760Y
Application number: CNU200820038080XU
Authority: CN
Inventors: 茅建生; 茅颖杰
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-06-12
Filing date: 2008-06-12
Publication date: 2009-03-18
Anticipated expiration: 2018-06-12

Abstract

The utility model relates to a soft driving power supply for a high power LED lamp with over current protection, provides a driving power supply for the high power LED lamp which has over current protection and has soft starting performance capable of effectively avoiding large transient damage such as unloading and cold starting, improves the working reliability of a high power LED lamp system greatly, and is characterized in that the driving power supply comprises an input power supply filter, a rectifier, a power factor boosting circuit and a pulse width modulator. After AC/DC conversion of the pulse width modulator, through the soft starting control and the output of a constant current restrictor, the working reliability of the high power LED lamp system is improved. The power supply is used for an LED illuminating lamp, an LED explosion-proof lamp and an LED lamp for advertising as the type.

Description

The moving power supply of high-powered LED lamp floppy drive that contains overcurrent protection

Technical field

The utility model relates to the great power LED lamp driving power source, is specially the moving power supply of the high-powered LED lamp floppy drive that contains overcurrent protection.

Background technology

In the prior art, with alternating current 220V as the great power LED lamp driving power source of power drives, no matter this driving power be split, one or compact, isolated form and non-isolation type dual mode are all arranged.And all have by filter rectification, power factor and promote and pwm voltage AC/DC conversion formation high-power LED driving power source.As driving power overtension (〉 60V) or environment for use abominable, circuit does not have the preceding buffering that presets of working, and when load accident overcurrent, just inevitably there is the harm of getting rid of load, cold start-up and big transient state and overcurrent operation, cause high-powered LED lamp work unreliable, unstable, even local and even all damages in the lamp, the fault of turning off the light frequently occurs.

Summary of the invention

At getting rid of shortcoming and the problem that load, cold start-up and big transient state and load over-current harm are easily broken down as what the high-powered LED lamp of power drives was subjected to that electric power network and circuit structure cause with alternating current 220V; the utility model provides a kind of moving power supply of the high-powered LED lamp floppy drive soft start performance, that contain overcurrent protection that has, to improve the functional reliability of great power LED lamp system.

The technical scheme that provides according to the utility model, the moving power supply of described floppy drive comprises power filter rectifier, power factor lifter and the pulse width modulator that order is electrically connected, it is characterized in that: the output in pulse width modulator connects soft starting circuit, output at soft starting circuit connects the constant current mode flow restricter, and the output of constant current mode flow restricter connects output filter again.The constant current feature of the constant current device of routine as the restriction of the overcurrent protection under the load faulty condition, is made system's reliability service.

In soft starting circuit, resistance 5R1A that links to each other with integrated circuit 5U1 and 5R1B and 5R2 are the divider resistance of integrated circuit 5U1 output voltage, the electric capacity 5C1 that links to each other with integrated circuit 5U1 is a delay capacitor, the resistance 5R1B that is used for control characteristic is connected between the collector electrode and emitter of triode 5Q1, and described triode 5Q1 is operated in the linear amplification zone.

In power initiation moment because the terminal voltage of the delay electric capacity in the soft start control loop is 0, the effect of control loop makes output only approach 70～80% of operating voltage, along with charging to delay electric capacity, finally make load obtain the operating voltage of LED, make load obtain step-like " soft " voltage operation mode, avoided loaded work piece loop electronic device and loaded on the impact of the operating voltage of the big transient state that is subjected in the start-up course.

The mode of operation that also has the constant current mode current limliting in the utility model high-power driving power supply all is effectively protected electric power loop and circuit load.

The utility model has the advantages that: adopt after the said structure, because the startup of having adopted soft starting mode to avoid load not had buffer starting is impacted high-powered LED lamp under high-voltage operation during (〉 100V) get rid of load, cold start-up and big transient state and overcurrent move equiprobable harm and avoided effectively.Improved the reliability of power-supply system and load running, the cost performance of system is well promoted.

Description of drawings

Fig. 1 is an electric theory diagram of the present utility model.

Fig. 2 is the soft start electrical schematic diagram.

Fig. 3 is a constant current mode current limliting electrical schematic diagram.

Embodiment

See Fig. 1, the moving power supply of described floppy drive comprises power filter rectifier, power factor lifter and the pulse width modulator that order is electrically connected, it is characterized in that: the output in pulse width modulator connects soft starting circuit, output at soft starting circuit connects the constant current mode flow restricter, and the output of constant current mode flow restricter connects output filter again.The constant current feature of the constant current device of routine as the restriction of the overcurrent protection under the load faulty condition, is made system's reliability service.

See Fig. 2, in soft starting circuit, resistance 5R1A that links to each other with integrated circuit 5U1 and 5R1B and 5R2 are the divider resistance of integrated circuit 5U1 output voltage, the electric capacity 5C1 that links to each other with integrated circuit 5U1 is a delay capacitor, the resistance 5R1B that is used for control characteristic is connected between the collector electrode and emitter of triode 5Q1, and described triode 5Q1 is operated in the linear amplification zone.

Power supply front end circuit (AC/DC change-over circuit) has comprised power supply prefilter, rectifier, power factor lifter and pulse width modulator.Realized the conversion of AC/DC by these circuit, offered the great power LED load by soft starting circuit and constant current mode flow restricter and output filter again, with reliable and stable work.

See Fig. 2, soft starting circuit comprises resistance 5R1A, 5R1B, 5R2,5R3,5R4,5R5, electric capacity 5C1,5C2, diode 5D1,5D2, triode 5Q1 and integrated circuit 5U1.Resistance 5R1A and 5R1B and 5R2 are the divider resistance of integrated circuit 5U1 (LM317) output voltage, and output voltage is: V=1.25[1+ (5R1A+5R1B)/5R2].In the moment of energized, the terminal voltage of electric capacity 5C2 (delay capacitor) is 0, triode 5Q1 conducting, and the output voltage of integrated circuit 5U1 is the terminal voltage on the resistance R 2, about 110V (as the operating voltage of load LED).Along with the charging of output voltage to electric capacity 5C2, the terminal voltage of electric capacity 5C2 rises gradually, the base voltage of triode 5Q1 raises gradually, the collector electrode of triode 5Q1 and the resistance between emitter also raise gradually, electric current I ce also reduces gradually, make the dividing potential drop effect of resistance 5R1B reduce gradually, 5Q1 ends until triode.Corresponding therewith, the output voltage on the electric capacity 5C2 also increases thereupon, reaches specified LED driving voltage value.Adjust the fine setting that resistance 5R3 and electric capacity 5C2 value can obtain time of delay.The effect of diode 5D2 is that capacitor C 2 can be passed through load discharge, makes the temporal characteristics that possesses soft start when repeated priming equally.

See Fig. 3, forming constant-current source with integrated circuit 6U1 (LM317) is that the typical case one of uses, and is not under the constant current state of using it under conventional the application in the utility model, but with its constant current feature as the overcurrent limiting under the load faulty condition.Mandatory declaration and attention be when the operating current of integrated circuit 6UI is set, must select just can normally play metering function more than or equal to 120% circuit of loaded work piece electric current.Electric capacity 6C1,6C2,6C3,6C4, resistance 6R2 and diode 6D1 be respectively filtering, decoupling and power protection and buffer action set.

In power initiation moment because the terminal voltage of the delay electric capacity in the soft start control loop is 0, because the effect of control loop makes output only approach 70～80% of operating voltage, along with charging to delay electric capacity, finally make load obtain the operating voltage of LED, make load obtain step-like " soft " voltage operation mode, avoided loaded work piece loop electronic device and loaded on the impact of the operating voltage of the big transient state that is subjected in the start-up course.

With a delay capacitor and be operated in the collector electrode of triode 5Q1 in linear amplification zone and high-power LED driving power source that the Characteristics Control resistance 5R1 between emitter and 5R2 dividing potential drop feature embody as soft start function.The preposition AC/DC circuit of soft start and constant current mode flow restricter is the AC/DC translation circuit that filter rectification, power factor lifter and pulse width modulator are formed.

Claims

1, the moving power supply of high-powered LED lamp floppy drive that contains overcurrent protection; comprise power filter rectifier, power factor lifter and pulse width modulator that order is electrically connected; it is characterized in that: the output in pulse width modulator connects soft starting circuit; output at soft starting circuit connects the constant current mode flow restricter; the output of constant current mode flow restricter connects output filter again; the constant current feature of the constant current device of routine as the restriction of the overcurrent protection under the load faulty condition, is made system's reliability service.

2, the moving power supply of high-powered LED lamp floppy drive that contains overcurrent protection according to claim 1; it is characterized in that: in soft starting circuit; the resistance (5R1A) that links to each other with integrated circuit (5U1) and (5R1B) with (5R2) be the divider resistance of integrated circuit (5U1) output voltage; the electric capacity (5C1) that links to each other with integrated circuit (5U1) is delay capacitor; the resistance (5R1B) that is used for control characteristic is connected between the collector electrode and emitter of triode (5Q1), and described triode (5Q1) is operated in the linear amplification zone.