CN2469655Y - Power source of gas discharge lamp by high-frequency igniting - Google Patents

Abstract

The utility model relates to a power source of gas discharge lamp driven by high-frequency. The utility model is characterized in that a direct current which is calibrated by power factor provides the energy. An inductor and a capacitance are in series connected with the direct current power source, thus producing sine alternating voltage whose basic frequency f is equal to 1/(2pi*), whose feather resistance is *, and whose peak value is 2Ec. Two electronic switches connect in parallel with the two ends of the capacitance. A high-frequency inductance ballast connects in parallel with the two ends of the electronic switch after connecting with the gas discharge lamp in series. The utility model has the advantages of low current wave crest ration (without impact to lamps), continuous lamp current, no frequency flash and no sound resonance.

Description

Power supply for high-frequency driven gas discharge lamp

The utility model relates to the power supply of gas discharge lamp, a kind of specifically power supply for high-frequency driven gas discharge lamp.

High strength, high-power gas charging lamp need up to thousands of volt voltage triggered gas breakdown, and be negative resistance charactertistic, start-up time is long, electric current is big, in power frequency (50-60 He Zhi), have operating current dead between, repeat each second up to a hundred times, produce bigger current wave crest ratio, seriously influenced the useful life of fluorescent tube, in three-phase power supply system, zero line produces big harmonic current, can cause the damage and the disaster hidden-trouble of electric power system to electrical network.At present in order to address the above problem, often take to use electric ballast to start high-voltage gas discharging light, as just provide in the disclosed patent 96119658.0 of Patent Office of the People's Republic of China a kind of permanent power adjustment, High Power Factor, low harmonic content, starting current low, can allow the electronic ballast for high-pressure discharge lamp that open a way for a long time in the high-voltage lamp two ends, short-circuit condition is charged, though the foregoing invention patent solves some above-mentioned problems, but still existence is adopted hard switching technology, circuit complexity, high-frequency harmonic is arranged, is adjusted loaded down with trivial details defective.

The purpose of this utility model provides a kind of characteristics that both had foregoing invention, be again a kind of high frequency sine, low current crest than (lamp is not had impact), lamp current continuously, the power supply for high-frequency driven gas discharge lamp of no stroboscopic, no acoustic resonance, to overcome above-mentioned deficiency.

To achieve these goals, characteristics of the present utility model are connected on the DC power supply Ec by inductor L1 and capacitor C1 series connection for providing energy by a DC power supply Ec through power factor correction, produce dominant frequency and are $f=1/(2\∏\sqrt{L1C1})$ , characteristic impedance is

, to produce peak value at capacitor C1 two ends be the sinusoidal voltage of 2Ec;

Be connected in parallel on capacitor C1 two ends after two electronic switch K1, K2 series connection;

Be parallel with sustained diode 1, D2 on electronic switch K1, the K2 respectively;

Be connected in parallel on electronic switch K2 two ends after one high-frequency inductor ballast L2 being arranged and gaseous discharge lamp G connecting.

Above-mentioned inductor L1 is made of transformer B1, above-mentioned electronic switch K1, K2 are made of switching tube Q1, Q2, above-mentioned high-frequency inductor ballast L2 is made of high frequency transformer B2, the break-make that one control module M control switch pipe Q1, Q2 are arranged, have between the negative temperature coefficient resister NTC of a series connection and capacitance C3 be connected between gaseous discharge lamp G and the DC power supply Ec negative pole, also have between a building-out capacitor C2 one termination two switching tube Q1, Q2, its other end is connected between gaseous discharge lamp G and the negative temperature coefficient resister NTC.

The input of above-mentioned control module M is connected to the secondary n12 of transformer B1 and detects the output signal n32 of the current transformer B3 of capacitor C1, its output has enabling signal a, the b of switching tube Q1, Q2 break-make control signal and gaseous discharge lamp G, this enabling signal a, b insert the secondary n22 of high frequency transformer B2, also are connected with current-limiting resistance R between control module M and the positive level of capacitor C1.

Above-mentioned control module M is made of rectifying and wave-filtering DC power supply, signal amplification circuit, comparison phase discriminator, frequency discrimination phase lock circuitry, level shift circuit, current follower circuit, bistable circuit and start-up circuit.

The utility model because adopt to isolate start, the principle that keeps in the branch source, make the utlity model has that the low current crest is more continuous than (lamp is not had impacts), lamp current, the advantage of no stroboscopic, no acoustic resonance.The utility model circuit is simple, volume is little.

Fig. 1 is circuit topology figure of the present utility model.

Fig. 2 is the utility model embodiment circuit theory diagrams.

Fig. 3 is the utility model control module circuit block diagram.

Further specify the utility model below in conjunction with drawings and Examples.

Resonant network in electric power network after the DC power supply Ec after power factor adjustment and the voltage stabilizing is for inductor L1, a capacitor C1 series connection, (as Fig. 1) produces frequency f=1/L1C1 at capacitor C1 two ends, peak value is the sinusoidal high frequency voltage of 2Ec, the energy of supply gas discharge lamp G behind electronic switch K1, K2 and high-frequency inductor ballast L2 ballast.

The elementary n11 of transformer B1 and capacitor C1 form the dominant frequency resonant network in an embodiment; switching tube Q1, Q2 are controlled switchs; M is the control module of input, processing and switching tube Q1, Q2; n21 among the high frequency transformer B2 is the high frequency ballast inductance; gaseous discharge lamp G is load; negative temperature coefficient resister NTC is the protective resistance of surge current when reducing the lamp startup; capacitor C2 is the rectification building-out electric capacity of gaseous discharge lamp G when starting path and operation, and resistor R is the current-limiting resistance of control module M work primary power when providing.

In the foregoing circuit, when power supply Ec has electricity, power supply Ec charges to capacitor C1, after capacitor C1 electricity is full of, when the charging current of control module M detection capacitor C1 is zero, the secondary n12 no signal of transformer B1 when being zero (be the elementary n11 of transformer B1) simultaneously, control module M is from start-up circuit a, the b end sends lamp starting impulse signal, this pulse signal produces high pressure by high frequency transformer B2 at its elementary n21, by elementary n21, gaseous discharge lamp G and building-out capacitor C2 form the loop, gaseous discharge lamp G is lighted, control module M makes its conducting for switching tube Q1 signal simultaneously, this moment, capacitor C1 discharge was shinny in order to keep gaseous discharge lamp G, this moment high frequency transformer B2 secondary n22 feedback gas discharge lamp G keep current signal; When capacitor C1 discharge off, switching tube Q1 ends, during diode D2 afterflow, control module M makes its conducting for switching tube Q2 signal, it is shinny to continue to keep gaseous discharge lamp G by the energy storage of high frequency ballast inductance n21, when switching tube Q2 ended, control module M made its conducting (this moment, capacitor C1 dashed) for switching tube Q1 signal, finishes one-period.

When gaseous discharge lamp G opened a way, the secondary n22 of high frequency transformer B2 did not have feedback current, the uncontrollable switching tube Q2 of control module M conducting, and the storage of B1 level of transformer n12 noenergy, and entire circuit is in resting state; When gaseous discharge lamp G short circuit, B1 level of transformer n12 feedback quantity is big, and this moment, control module M stopped the work of switching tube Q1, Q2, and circuit also is a dormant state, power consumption hardly (＜1W).The secondary n23 of high frequency transformer B2 is the output winding when making transformer, can make other purposes.

Control module M is an independently comprehensive module, it provides power supply B1 level of transformer n12 the size of electric current to amplify shaping to amplifier A1, amplifier A2 amplifies shaping with size of current and the phase place of capacitor C1, produce above-mentioned two paths of signals through comparator at capacitor C1 two ends, and control electronic switch K1 conducting when capacitor C1 charging finishes behind the phase demodulation; Because the passive parameter (distributed capacitance of the distribution of transformer B2 and active device (switching tube etc.), circuit induction reactance etc.) influenced dominant frequency, so the signal of amplifier A2 amplifies shaping with the load current signal that is detected by the elementary n21 among the high frequency transformer B2 through amplifier A3, after phase demodulation is phase-locked, send electronic switch K2 control signal by follower, through phase demodulation lockin signal control ratio than phase discriminator, because high frequency transformer B2 is a high frequency ballast reactor, it is again accumulator, when energy storage for lamp when a certain amount of, just can make electronic switch K1 conducting (be electronic switch K2 must reliable by); Flip-flop circuit is controlled to thyristor and is sent high-voltage lamp triggering starting impulse, send preferential Continuity signal for simultaneously electronic switch K1, if the normal place in circuit of lamp, transformer B1 just has electric current to pass through, this signal blocks bistable circuit after amplifier A3 amplifies shaping, it is the thyristor Triggerless that its no high voltage control signal is produced, start-up circuit just can not produce high pressure and insert high frequency transformer B2, thereby guarantees the safe operation of device; The working power of control module is taken out through the secondary n12 of transformer B1, supplies with after voltage stabilizing; Level shift circuit can be through external transformer and photoelectricity coupling.

Switching tube Q1 of the present utility model, Q2 can adopt power MOS pipe, IGB power tube, high speed thyristor etc.

The part of not describing in detail more of the present utility model undoubtedly is clearly for those skilled in the art, so need not to describe.

Claims (4)

1, a kind of power supply for high-frequency driven gas discharge lamp is characterized in that: provide energy by a DC power supply Ec through power factor correction, be connected on the DC power supply Ec by inductor L1 and capacitor C1 series connection, the generation dominant frequency is $f=1/(2\∏\sqrt{L1C1})$ , characteristic impedance is

, to give birth to peak value be the sinusoidal voltage of 2Ec;

Be connected in parallel on capacitor C1 two ends after two electronic switch K1, K2 series connection;

Be parallel with sustained diode 1, D2 on electronic switch K1, the K2 respectively;

Be connected in parallel on electronic switch K2 two ends after one high-frequency inductor ballast L2 being arranged and gaseous discharge lamp G connecting.

2, according to the described power supply for high-frequency driven gas discharge lamp of claim 1, it is characterized in that: inductor L1 is made of transformer B1, electronic switch K1, K2 is by switching tube Q1, Q2 constitutes, high-frequency inductor ballast L2 is made of high frequency transformer B2, one control module M control switch pipe Q1 is arranged, the break-make of Q2, have between the negative temperature coefficient resister NTC of a series connection and capacitance C3 be connected between gaseous discharge lamp G and the DC power supply Ec negative pole, also have two switching tube Q1 of a building-out capacitor C2 one termination, between the Q2, its other end is connected between gaseous discharge lamp G and the negative temperature coefficient resister NTC.

3, according to claim 1 or 2 described power supply for high-frequency driven gas discharge lamp, it is characterized in that: the input of control module M is connected to the secondary n12 of transformer B1 and detects the output signal n32 of the current transformer B3 of capacitor C1, its output has enabling signal a, the b of switching tube Q1, Q2 break-make control signal and gaseous discharge lamp G, this enabling signal a, b insert the secondary n22 of high frequency transformer B2, also are connected with current-limiting resistance R between control module M and the positive level of capacitor C1.

4, according to claim 1 or 2 or 3 described power supply for high-frequency driven gas discharge lamp, it is characterized in that: control module M is made of rectifying and wave-filtering DC power supply, signal amplification circuit, comparison phase discriminator, frequency discrimination phase lock circuitry, level shift circuit, current follower circuit and bistable circuit.

Images