CN212137957U - Electronic ballast drive circuit based on triple resonance - Google Patents

Abstract

The utility model discloses an electronic ballast drive circuit based on triple resonance, the drain electrode of Q1 is connected with the positive pole of the direct current power supply, the source electrode is connected with the drain electrode of Q2, and the source electrode of Q2 is connected with the negative pole of the direct current power supply; c1 and C2 are connected in series, and C3 and C4 are connected in series and then are respectively connected between the positive pole and the negative pole of the direct current power supply; the positive electrode of the direct current power supply is connected with the negative electrode of the direct current power supply after being reversely connected with the D1 and the D2; a lead is led out from a connecting line of a Q1 source and a Q2 drain to be connected with L1 and C6, then connected with a LAMP filament of LAMP, then connected with a normally open contact of JD, then connected with the other LAMP filament of LAMP, and then connected with a connecting line of C1 and C2; the connecting line of C3 and C4 is connected with the connecting line of D1 and D2 by a lead wire, then connected with C5 and then connected with the connecting line of L1 and C6. Adopt the utility model discloses a resonance voltage that needs when can producing mercury lamp glow starting during electronic ballast high frequency resonance, nevertheless resonance current descends at double, flows through field effect transistor's electric current greatly reduced, has increased the reliability of switch tube.

Description

Electronic ballast drive circuit based on triple resonance

Technical Field

The utility model relates to an electronic ballast drive circuit.

Background

As shown in fig. 1, field effect transistors Q11 and Q21 are switching transistors of the half-bridge circuit and perform an inversion function, capacitors C11 and C21 are half-bridge capacitors, L11 is a current-limiting inductor and also a resonant inductor, C51 is a resonant capacitor, and L11 and C51 resonate to generate a starting voltage; in fig. 1, the two stages of preheating and starting the lamp tube are a loop, namely a positive half cycle Q11-L11-filament-C51-filament-C21 and a negative half cycle Q21-L11-filament-C51-filament-C11, so that the LC resonance can only be kept at the fundamental frequency of the half-bridge inverter loop, and the LC resonance not only can increase the voltage, but also can increase the current flowing through the switching tubes Q11 and Q21 on the half-bridge inverter circuit; the driving circuit can be used on a mercury lamp with low power, and can not be used for mercury lamps with high power of more than 150W and the like, because the starting voltage of lamp tubes of the mercury lamp with high power is very high, the current flowing through the switching tubes Q11 and Q21 is very large, the switching tubes Q11 and Q21 are easily damaged due to overcurrent at the moment of starting the lamp tubes, and the reliability of products is greatly influenced.

SUMMERY OF THE UTILITY MODEL

The utility model aims at solving the above-mentioned problem that exists among the prior art, provide an electronic ballast drive circuit based on cubic resonance, can produce the resonance voltage that mercury lamp needed when starting luminance when adopting this drive circuit's electronic ballast high frequency resonance, nevertheless resonance current can descend doubly, flows through field effect transistor's electric current greatly reduced, has increased the reliability of switch tube, and mercury lamp no matter how much high power is all very suitable for.

In order to achieve the above object, the technical solution of the present invention is: an electronic ballast drive circuit based on triple resonance comprises a half-bridge inverter circuit and an LC resonance lighting circuit; the half-bridge inverter circuit comprises a half-bridge driving chip IC1, a field effect transistor Q1 and a field effect transistor Q2; the LC resonance lighting circuit comprises capacitors C1, C2, C3, C4, C5 and C6, diodes D1 and D2, a current-limiting inductor L1 and a relay JD; the drain electrode of the field effect transistor Q1 is connected with the positive electrode of the direct current power supply, the source electrode of the field effect transistor Q2 is connected with the drain electrode of the field effect transistor Q2, and the source electrode of the field effect transistor Q2 is connected with the negative electrode of the direct current power supply; the negative electrode of the direct current power supply is connected with the common terminal; the capacitors C1 and C2 are connected in series and then connected between the positive pole and the negative pole of the direct current power supply; the capacitors C3 and C4 are connected in series and then connected between the positive pole and the negative pole of the direct current power supply; the positive pole of the direct current power supply is connected with the negative pole of the direct current power supply after being reversely connected with the diodes D1 and D2 in sequence; a lead is led out from a connecting line of a source electrode of the field effect tube Q1 and a drain electrode of the field effect tube Q2 and is sequentially connected with a current-limiting inductor L1, a capacitor C6, a filament of the mercury LAMP LAMP, a normally open contact JD1B of the relay JD, another filament of the mercury LAMP LAMP, and a connecting line of the capacitors C1 and C2; one end of a coil JD1A of the relay JD is connected with a 12V single-ended flyback power supply, and the other end of the coil JD1A of the relay JD is connected with a public end; the connecting line of the capacitors C3 and C4 and the connecting line of the diodes D1 and D2 are connected by a lead wire and then connected with the capacitor C5 and then connected with the connecting line of the current-limiting inductor L1 and the capacitor C6; the gates of the fets Q1 and Q2 are connected to the high-side driver pin and the low-side driver pin of the half-bridge driver IC1, respectively.

The utility model discloses a half-bridge inverter circuit and LC resonance of electronic ballast circuit turn on a lamp the return circuit, DC power supply comes from the DC power supply after the alternating current rectification filter, and the 12V power comes from a single-ended flyback power supply of electronic ballast.

In the preheating stage of the lamp tube, a coil JD1A of the relay JD is switched on, and a normally open contact JD1B is closed; a preheating loop: when the alternating current power supply of the electronic ballast is in the positive half cycle, the positive pole of the direct current power supply returns to the negative pole of the direct current power supply from Q1-L1-C6-filament of LAMP-closed normally open contact JD 1B-another filament-C2 of LAMP to form a closed loop; when the alternating current power supply of the electronic ballast is in a negative half cycle, the negative electrode of the direct current power supply returns to the positive electrode of the direct current power supply from Q2-L1-C6-filament of LAMP-closed normally open contact JD 1B-another filament-C1 of LAMP to form a closed loop.

In the tube starting stage, the coil JD1A of the relay JD is disconnected, the normally open contact JD1B is disconnected, and the starting loop: when the alternating current power supply of the electronic ballast is in the positive half cycle, the positive pole of the direct current power supply returns to the negative pole of the direct current power supply from Q1-L1-C5-C4// D2 to form a closed loop; when the alternating current power supply of the electronic ballast is in the negative half cycle, the negative pole of the direct current power supply returns to the positive pole of the direct current power supply from Q2-L1-C5-C3// D1 to form a closed loop.

In the normal working stage of the lamp tube, the coil JD1A of the relay JD is disconnected, the normally open contact JD1B of the relay JD is disconnected, and the working circuit: when the alternating current power supply of the electronic ballast is in the positive half cycle, the positive pole of the direct current power supply returns to the negative pole of the direct current power supply from Q1-L1-C6-lamp tube-C2 to form a closed loop; when the alternating current power supply of the electronic ballast is in the negative half cycle, the negative pole of the direct current power supply returns to the positive pole of the direct current power supply from Q2-L1-C6-lamp tube-C1 to form a closed loop.

The utility model discloses a L1 is current-limiting inductance, also be resonant inductance, C5 is resonant capacitance, L1 and C5 resonance produce the voltage of starting luminance, LC resonance is lighted a lamp circuit and is removed C1 and C2 main half-bridge electric capacity outside, supplementary half-bridge electric capacity such as C3// D1 and C4// D2 has been increased, electric capacity C6 and protection relay JD have been increased, make the fluorescent tube preheat the stage, the passageway that fluorescent tube start stage and fluorescent tube normal operating phase were walked is different. Because C5, C3// D1, C4// D2 only participate in the work in the tube glow starting stage, so can adjust the capacitance value properly, for the resonance frequency of LC chooses to resonate at the third frequency point of half-bridge fundamental wave frequency, the high-frequency resonance can produce the same resonance voltage that the mercury lamp needs when starting, but the resonant current will drop by times, thus make the electric current flowing through field effect tube Q1, Q2 reduce greatly, thus increase the reliability of the switch tube, no matter how many high-power mercury lamps are suitable.

Drawings

FIG. 1 is a schematic circuit diagram of a prior art;

fig. 2 is a schematic circuit diagram of the present invention.

Detailed Description

The invention is further described with reference to the accompanying drawings and specific embodiments.

As shown in fig. 2, the present embodiment includes a half-bridge inverter circuit and an LC resonant lighting circuit. The half-bridge inverter circuit comprises a half-bridge driving chip IC1, a field effect transistor Q1 and a field effect transistor Q2; the LC resonant lighting circuit comprises capacitors C1, C2, C3, C4, C5 and C6, diodes D1 and D2, a current-limiting inductor L1 and a relay JD. The drain electrode of the field effect transistor Q1 is connected with the positive electrode of the direct current power supply, the source electrode of the field effect transistor Q2 is connected with the drain electrode of the field effect transistor Q2, and the source electrode of the field effect transistor Q2 is connected with the negative electrode of the direct current power supply; the negative electrode of the direct current power supply is connected with the common terminal; the capacitors C1 and C2 are connected in series and then connected between the positive pole and the negative pole of the direct current power supply; the capacitors C3 and C4 are connected in series and then connected between the positive pole and the negative pole of the direct current power supply; the positive pole of the direct current power supply is connected with the negative pole of the direct current power supply after being reversely connected with the diodes D1 and D2 in sequence; a lead is led out from a connecting line of a source electrode of the field effect tube Q1 and a drain electrode of the field effect tube Q2 and is sequentially connected with a current-limiting inductor L1, a capacitor C6, a filament of the mercury LAMP LAMP, a normally open contact JD1B of the relay JD, another filament of the mercury LAMP LAMP, and a connecting line of the capacitors C1 and C2; one end of a coil JD1A of the relay JD is connected with a 12V single-ended flyback power supply, and the other end of the coil JD1A of the relay JD is connected with a public end; the connecting line of the capacitors C3 and C4 and the connecting line of the diodes D1 and D2 are connected by a lead wire and then connected with the capacitor C5 and then connected with the connecting line of the current-limiting inductor L1 and the capacitor C6; the gates of the fets Q1 and Q2 are connected to the high-side driver pin and the low-side driver pin of the half-bridge driver IC1, respectively.

Naturally, the invention also relates to other embodiments, and those skilled in the art can make corresponding changes and modifications according to the invention without departing from the spirit and substance of the invention, and these corresponding changes and modifications should be considered as improvements in the equivalent technology, and fall within the scope of protection of the claims of the invention.

Claims (1)

1. The utility model provides an electronic ballast drive circuit based on cubic resonance which characterized in that: the circuit comprises a half-bridge inverter circuit and an LC resonance lighting circuit; the half-bridge inverter circuit comprises a half-bridge driving chip IC1, a field effect transistor Q1 and a field effect transistor Q2; the LC resonance lighting circuit comprises capacitors C1, C2, C3, C4, C5 and C6, diodes D1 and D2, a current-limiting inductor L1 and a relay JD; the drain electrode of the field effect transistor Q1 is connected with the positive electrode of the direct current power supply, the source electrode of the field effect transistor Q2 is connected with the drain electrode of the field effect transistor Q2, and the source electrode of the field effect transistor Q2 is connected with the negative electrode of the direct current power supply; the negative electrode of the direct current power supply is connected with the common terminal; the capacitors C1 and C2 are connected in series and then connected between the positive pole and the negative pole of the direct current power supply; the capacitors C3 and C4 are connected in series and then connected between the positive pole and the negative pole of the direct current power supply; the positive pole of the direct current power supply is connected with the negative pole of the direct current power supply after being reversely connected with the diodes D1 and D2 in sequence; a lead is led out from a connecting line of a source electrode of the field effect tube Q1 and a drain electrode of the field effect tube Q2 and is sequentially connected with a current-limiting inductor L1, a capacitor C6, a filament of the mercury LAMP LAMP, a normally open contact JD1B of the relay JD, another filament of the mercury LAMP LAMP, and a connecting line of the capacitors C1 and C2; one end of a coil JD1A of the relay JD is connected with a 12V single-ended flyback power supply, and the other end of the coil JD1A of the relay JD is connected with a public end; the connecting line of the capacitors C3 and C4 and the connecting line of the diodes D1 and D2 are connected by a lead wire and then connected with the capacitor C5 and then connected with the connecting line of the current-limiting inductor L1 and the capacitor C6; the gates of the fets Q1 and Q2 are connected to the high-side driver pin and the low-side driver pin of the half-bridge driver IC1, respectively.

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