KR0124977B1 - High frequency resonant type electronic ballast circuit - Google Patents

Abstract

The high frequency resonant electronic ballast circuit comprises: a a power source part to supply power source; a booster circuit to boost the power source from the power source part; a high frequency resonant converter circuit converting the output of the booster circuit to a high AC voltage; a discharge lamp to emit light by receiving the output of the high frequency resonant converter circuit; a rectangular wave generator receiving the output of the booster circuit as an input and generating a rectangular wave; a constant voltage controller supplying a stabilized DC voltage; a driving signal controller driving a main switching device in the high frequency resonant converter circuit; and a zero voltage switching driving circuit to perform zero voltage switching.

Description

High Frequency Resonant Electronic Ballast Circuit for Automotive Discharge Lamps

1 is a block diagram illustrating a power system of a conventional vehicle.

2 is a circuit diagram of a conventional automobile lighting system.

3 is a block diagram of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

4 is a detailed block diagram of a high frequency resonance electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

5 is a detailed circuit diagram of a feedback circuit of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

6 is a comparator output waveform diagram of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

7 is a voltage waveform diagram across the drain and source of the switching element of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

8 is an applied voltage waveform diagram of an inductor in a booster circuit of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

9 is a drain current waveform diagram of a transistor in a booster circuit of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention.

10 is a waveform diagram of a high voltage current in a booster circuit of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

11 is a waveform diagram of a current inductor in the turn-off state of the switching element of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention.

12 is a drive signal waveform diagram of a juice switching element of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention.

13 is a voltage waveform diagram at both ends of the second main switching element in the square wave generator of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention.

14 is a waveform diagram of a high frequency resonance current in a square wave generator of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

15 is a voltage waveform diagram between a center intersection of upper and lower ends of a juice switching element and a center intersection of a DC high voltage distribution capacitor in a square wave generator of a high frequency resonance electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

FIG. 16 shows the voltage across the resonant capacitor and the voltage between both ends of the high voltage discharge lamp in the high frequency resonant circuit of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention.

17 is an equivalent circuit diagram of a high frequency resonant converter including a discharge lamp in a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

100: power supply unit, 200: booster circuit,

300: driving circuit of the juice switching element, 400: high frequency resonant converter circuit,

DL: high voltage discharge lamp, V _S : DC voltage source,

L _B : inductor, Q _B : switching element,

V _BB : DC high voltage, D _B : Diode,

210: feedback circuit, 220: triangle wave generator,

230: comparator, M ₁ , M ₂ : juice switching device,

310: constant voltage controller, 320: square wave generator,

T _D : driving transformer, N ₁ : primary winding,

330: drive signal controller, N ₂ , N ₃ : drive transformer winding,

C _M1 , C _M2 : condenser, C ₁ , C ₂ : condenser,

L _R : resonant inductor, CR: resonant capacitor

410,420: upper and lower switching unit, T ₁ : high voltage insulation transformer,

430: resonant circuit portion, 211: detector,

212: adder, R ₁ , R ₂ , R ₃ , R ₄ , R ₅ , R ₆ : resistance,

OP ₁ : polarity inversion amplifier, V _D : output potential,

f ₁ : cutoff frequency, 213: proportional integrator,

IC ₁ : square wave generating chip, R ₃₃ : resistance,

Q ₃₁ , Q ₃₂ : transistor, D ₃₁ : diode,

C ₀ : condenser, i _R : resonant current

The present invention relates to a discharge lamp of a vehicle, and more specifically, to a high frequency resonant electronic ballast circuit for a vehicle discharge lamp for lighting a discharge lamp having a high Luminous Efficacy of a light source in an automobile system. It is about.

These days, automotive lighting systems use light from high-temperature incandescent radiation such as filament incandescent bulbs and tungsten halogen bulbs, so that the efficiency of light sources per unit power consumption (Luminous Efficacy of Source) is about 16-20. It is much lower than the discharge lamp. In addition, the high temperature filament is not only low reliability due to the vibration of the vehicle but also very short lifespan is required to change frequently.

Increasing the power consumption of various electronic devices of the car is not only directly related to the car engine, but also has a problem of increasing the capacity in selecting a generator and a battery. In addition, considering that the efficiency of converting automobile fuel into electric energy is about 38% or less, the high efficiency of the automotive lighting system is very important not only for saving energy but also for protecting the environment.

Conventionally, the technology related to the discharge lamp of the automobile is Taiwan Patent No. 200626 (Patent application date: April 10, 1991) and United States Patent No. 3969652 (Patent application date: July 13, 1976), No. 4119907 ( Patent application date: October 10, 1978), No. 442229 (Patent application date: July 24, 1979), and No. 4999547 (Patent application date: March 12, 1991).

1 is a block diagram showing a power supply diagram of a conventional automobile, and FIG. 2 is a circuit diagram of a conventional automobile lighting system.

As shown in FIG. 1, a power supply system of a conventional vehicle includes: an engine 1; A generator 2; A regulator and a charger 3; A battery 4; It consists of a lamp 5.

First, when power is applied, fuel is converted into mechanical energy in the engine 1 of the vehicle, and mechanical energy is converted into electrical energy by the vehicle generator 2, and the converted energy is stored by the battery by the regulator and the charger 3. (4) is charged and applied to the lamp. As can be seen from such a structure, the power consumption of the lamp and various electrical appliances is directly related to the automobile engine. Therefore, efficient use of power is important.

As shown in FIG. 2, the circuit of a conventional automotive lighting system operates by applying current to the lamp 8 in series via a switch 7 at a power source 60.

However, as described above, although the configuration of the conventional automotive lighting system is very simple, the optical radiation efficiency of the incandescent lamp is about 10%, which is very low. That is, the visible light emission efficiency of the vehicle fuel is less than about 3%, for example, to obtain the electrical energy of 100W, about 3,300W of fuel is required.

On the other hand, High Intensity Discharge Lamp using visible light emission by discharge in high-pressure gas or steam is a high-brightness light source with a light emission efficiency of about 80lm / w. Not only can it provide brightness, but its lifespan is about eight times longer.

However, the above-described discharge lamp cannot be turned on by the low DC voltage as in a vehicle, and thus cannot be directly applied to a vehicle lighting system (initial discharge start voltage: 2.0 to 30 KV _{P is} required).

Therefore, an object of the present invention is to solve the disadvantages of the related art, and is a high frequency resonant type for directly turning on a high voltage discharge lamp in a high luminous efficiency and long life HID (High Intensity Discharge) lamp in an automobile lighting system. It is to provide a high frequency resonant electronic ballast circuit.

The configuration of the present invention to achieve the above object, the power supply for supplying power; A booster circuit for boosting power from the power supply unit; A zero voltage switching driving circuit for high frequency zero voltage switching operation; A high frequency resonant converter circuit for converting into a high voltage AC voltage using the booster output as an input; It is made of discharge lamp for emitting light.

The booster circuit is characterized in that to boost the applied DC low voltage of 12V or 24V about 2 ~ 30 times.

The booster circuit includes an inductor for accumulating magnetic energy by a switching action of the switching element; A diode for rectifying the accumulated energy to a DC high voltage; A feedback circuit for feeding back a DC high voltage which is an output voltage of the booster; A triangular wave generator for outputting a triangular wave for controlling the booster output; The comparator is configured to compare the output value of the feedback circuit to drive the switching element.

The feedback circuit includes: a detector for detecting the magnitude of the booster output voltage and inverting polarity; An adder which adds a reference voltage and the detector output voltage to output an error voltage; It is characterized in that it is composed of a proportional integrator that is proportional to the booster output voltage and maintains stable operation even in the high frequency switching frequency range by using the error voltage as an input.

The zero voltage switching driving circuit includes: a square wave generator for inputting the booster output voltage and generating a square wave; A constant voltage controller for supplying a stabilized DC voltage; And a drive signal controller for driving the output of the square wave generator to a main switching element in the high frequency resonant converter circuit using an isolation transformer.

The high frequency resonant converter circuit includes the booster output voltage as an input, an upper end of a juice switching element; Juice lowering device bottom; It is characterized by consisting of a high frequency resonant circuit.

The high-frequency resonant circuit is characterized in that the inductor and capacitor for the series resonant operation and the insulating transformer that can sufficiently discharge the high-voltage discharge lamp by adjusting the voltage ratio while electrically insulated in the lighting.

The high frequency resonant converter circuit includes a driving transformer for maintaining a switching operation by the positive feedback action of the resonance current in the high frequency resonant circuit including a discharge lamp, and a ratio of the windings of the driving transformer and the diode in the driving signal controller. By regenerating a predetermined amount of resonant current through the charge in the capacitor in the square wave generator, characterized in that.

When described with reference to the accompanying drawings the most preferred embodiment which can easily implement this invention by the above configuration as follows.

3 is a block diagram of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention, Figure 4 is a detailed circuit diagram of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention. 5 is a detailed circuit diagram of a feedback circuit of a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to an embodiment of the present invention. 6 to 15 are operation waveform diagrams of respective parts of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention. FIG. 16 shows voltages between both ends of the resonant capacitor and both voltages and currents of the high-voltage discharge lamp in the high-frequency resonant circuit of the high-frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention, and FIG. 17 is an embodiment of the present invention. An equivalent circuit diagram of a high frequency resonant converter including a discharge lamp in a high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the present invention.

As shown in Figs. 3 and 4, the configuration of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention includes a DC voltage source (V _S : 100); The output of the inductor L _B to which the output of the DC voltage source V _S 100 is connected is connected to the diode D _B , and its output is proportional to the detector 211 and the proportional integrator 213 of the feedback circuit 210. A booster circuit 200 having a structure connected to the comparator 230 and an output of the triangle wave generator 220 connected to the comparator 230; The output of the booster circuit 200 is connected to a constant voltage controller 310 composed of resistors R ₃₁ , R ₃₂ , R ₃₃ , R ₃₄ , R ₃₅ , a diode D ₃₁ , and a transistor Q ₃₂ , The output is connected to a square wave generator 320 composed of a resistor (R _T ) and a capacitor (C _T ), the output of which is a drive signal controller composed of diodes (D ₁ , R ₂ , R ₃ , D ₄ ) A zero voltage switching driving circuit 300 having a structure connected to the 330; Up and down consisting of juice switching elements (M ₁ , M ₂ ), capacitors (C _M1 , C _M2 ), driving transformer windings (N ₂ , N ₃ ) to which the output of the zero voltage switching driving circuit 300 is connected. The switching units 410 and 420 may include a resonance circuit unit 430 having a structure connected to a resonance circuit unit 430 including a resonance inductor L _R , a resonance capacitor C _R , and a high voltage insulation transformer T ₁ ; The output of the resonant circuit unit 430 is connected and is composed of a capacitor (C ₁ , C ₂ ) for distributing DC high voltage (V _BB ).

Operation of the high frequency resonant electronic ballast circuit for a vehicle discharge lamp according to the embodiment of the present invention by the above configuration is as follows.

First, when power is applied by the automobile user, the operation of the high frequency resonant electronic ballast circuit for the vehicle discharge lamp according to the embodiment of the present invention is started.

When the operation starts, a current is output from the DC voltage source (VS) 100.

The output current is connected to the diode D _B through the inductor L _B , is input to the feedback circuit 210 of the booster circuit 200, the detector 211 and the proportional integrator 213 of the feedback circuit 210. It is input as) and it is output stably.

The output of the feedback circuit 210 and the output of the triangular wave generator 220 are input to the comparator 230.

The output of the booster circuit 200 is connected to a constant voltage controller 310 composed of resistors R ₃₁ , R ₃₂ , R ₃₃ , R ₃₄ , R ₃₅ , a diode D ₃₁ , and a transistor Q ₃₂ , The output is connected to a square wave generator 320 composed of a resistor (R _T ) and a capacitor (C _T ), the output of which is a drive signal controller composed of diodes (D ₁ , D ₂ , D ₃ , D ₄ ) 330 is output.

The output of the zero voltage switching driving circuit 300 is a juice switching device (M ₁ , M ₂ ), the capacitor (CM1, C _M2 ), the upper and lower switching unit consisting of a driving transformer winding (N ₂ , N ₃ ) ( And a resonant inductor (L _R ), a resonant capacitor (C _R ), and a high voltage insulating transformer (T ₁ ).

The output of the resonant circuit unit 430 is input to the capacitors C ₁ and C ₂ for distributing the DC high voltage V _BB to be output.

Detailed operation description of each circuit is as follows.

As shown in Figure 5, the operation of the feedback circuit 210 will be described in detail as follows.

The potential V _C ; V _BB 'of the node C is

The output potential (V _D ) of the polarity inverting amplifier (OP ₁ ) is

The error output potential Δv of the adder 212 that adds and outputs the reference voltage VR that sets the magnitude of the booster output voltage and the detector 211 output voltage V _BB is

Where R ₅ = R ₆

It is expressed as In addition, the proportional integrator 213 is composed of a resistor (R ₇ ), a capacitor (C ₇ ) and an error amplifier (OP ₂ ), the proportional gain (A _P ) and the cutoff frequency (f ₁ ) are as follows.

Therefore, the output V _PI of the proportional integrator 213 is

(Where ω = 2Πfs and fs is the switching frequency.)

The phase delay is 45 ° at the cutoff frequency f ₁ , and the gain of the proportional integrator 213 is maintained at 3 dB or more than the proportional gain A _P so that the output voltage V _PI of the proportional integrator 213 is Stabilizes.

The output voltage V _PI of the proportional integrator 213 and the output voltage V _T of the triangular wave generator 220 generate a signal having a waveform such as (A) and (B) of FIG. 6 through the comparator 230. Will print.

At this time, the comparator output voltage (V _G5 ) is the time (T _ON ) and turn-off time (T _Off ) of the turn of the power switching element (Q _B ) is controlled. 7 shows waveforms of the voltages V _D5 at both ends of the drain D and the source S of the switching element Q _B.

As shown in FIG. 8, the booster circuit 200 is applied with the voltage V _{5 to the} inductor L _B when the switching element Q _B is the turn-on time T _ON , as shown in FIG. As the drain current I _D of the waveform is supplied, magnetic energy is accumulated.

On the other hand, the voltage across the inductor at the turn-off time T _{Off of the} switching element Q _B is | V _BB -V _S |, and the high voltage current diode current I _{DB of the} waveform as shown in FIG. 10 is shown. Charges the capacitor C _B to induce the output voltage V _BB of the booster circuit 200.

Current of the switching device turns on the _{(Q B) (T ON)} , turn-off (T _Off) were showing a current (L _B) waveforms of inductor (L _B) in a state in claim 11 also, the inductor (L _B) ( I _LB ) varies in magnitude and slope as a function of the booster circuit 200 output current I _L. That is, when the booster output voltage V _BB is constant, the magnitude of the booster circuit output current I _L is proportional to the power supplied from the input power source V _S. Here, the inductor current I _LB is in continuous mode when the booster circuit output current I _L is as follows.

Therefore, in the steady state, the inductor current (I _LB ) change is equal, so the booster circuit output voltage (V _BB ) can be expressed as follows.

As can be seen from Equation (10), the DC high voltage V _BB for turning on the high voltage discharge lamp controls the ratio of the turn-on time T _ON and the turn-off time T _Off of the switching element Q _B. As a result, the optimum voltage can be set.

Next, the operation of the zero voltage driving circuit 300 in detail, the constant voltage for supplying a stable DC constant voltage (V _CC ) to the square wave generation chip (IC ₁ ) for the square wave generation having a dead time (t _d ) during the initial operation In operation of the controller 310, the voltage across the capacitor C ₀ is square wave generation chip through the resistor R ₃₃ , the transistor Q ₃₁ , and the diode D ₃₁ using the booster output voltage V _BB as the input voltage. When the rated voltage (V _CC ) of (IC ₁ ) is reached, the potential divided by the resistor (R ₃₄ ) and the resistor (R ₃₅ ) is applied to the base-emitter voltage (V _BE ) of the transistor (Q ₃₂ ). Q ₃₂ ) is turned on.

Thus, transistor Q ₃₁ is turned off by resistor R ₃₁ and resistor R ₃₂ . That is, after the booster 200 operates in the normal state, the DC high voltage V _BB is input to supply the stabilized DC constant voltage source V _CC necessary for the normal operation of the square wave generator 320.

Then, when the constant voltage source V _CC is supplied to the square wave generator 320, the square wave generation chip IC ₁ transmits a square wave output signal having a dead time to the primary winding N ₁ of the driving transformer T _D. Will be supplied. The frequency of the square wave generated at this time may be selected according to the values of the resistor (R _T ) and the capacitor (C _T ).

On the other hand, since the high frequency resonant current i _R as shown in FIG. 14 in the steady state always flows through the driving transformer winding N ₄ , the transformer ratio N ₁ / N to the winding N ₁ . _The electromotive force is induced in the winding N ₁ by ₄ ), and the capacitor C ₀ is charged by the onion rectification of the diodes D ₁ to D ₄ . At this time, the potential V _C0 of the capacitor C ₀ is

When the diode D ₃₁ is turned off, the transistor Q ₃₁ of the constant voltage constant voltage controller 310 for the initial operation of the square wave generation chip IC ₁ is turned off to minimize the loss.

Next, the operation of the high frequency resonant converter circuit 400 will be described in detail. The juice switching elements M ₁ and M ₂ have a dead time t _d as shown in the waveforms (A) and (B) of FIG. 12. ) Is applied by the zero voltage switching driving circuit 300.

Therefore, the capacitors C _M1 and C _M2 for zero voltage switching connected in parallel across the juice switching elements M ₁ and M ₂ during the dead time t _{d may} include a resonance circuit including a discharge lamp DL. The charging and discharging operation is performed by the current i _R of 430. At this time, the voltage V _D5 waveform across the juice switching element M ₂ becomes a trapezoidal shape as shown in FIG. 13. In addition, the resonance current (i _R ) flowing at this time is

The waveform is shown in FIG. Here, the voltage V _AB waveform between the center intersection A of the upper and lower ends 410 and 420 of the juice switching elements M ₁ and M ₂ and the center intersection B of the DC high voltage distribution capacitor C ₁ and C ₂ is As shown in FIG.

Meanwhile, the frequency f _R of the resonant current i _R flowing through the resonant circuit 330 is expressed as follows.

(Where R ₀ is the equivalent resistance value of the high-pressure discharge lamp DL).

FIG. 16 illustrates the voltage V _CR across the resonant capacitor C _R and the voltage V _DL and the current I _DL across the high-voltage discharge lamp DL in the high frequency resonant circuit 330. As shown in FIG. 17, an equivalent circuit of a resonant converter having a voltage V _AB applied to the high frequency resonant circuit 330 as a voltage source is shown in FIG.

Here, it is easy to set the high voltage discharge lamp DL according to the winding ratio N of the primary winding N _P and the secondary winding N ₅ of the high voltage insulation transformer T ₁ .

In order to control the current i _DL flowing through the equivalent resistance R ₀ of the high-pressure discharge lamp DL set as described above to a predetermined value, a design of the following conditions will be required.

On the other hand, the above-described high frequency resonant converter circuit 400 performs the switching operation at the instant when the voltage V _DS of both ends of the juice switching elements M ₁ and M ₂ is zero, so that the switching loss can be ignored. In addition, there is a characteristic that the switching operation can be realized even in the high frequency region above the audible frequency.

Therefore, the method of lighting by discharging the discharge lamp at a high frequency is similar to natural light having almost no phase effect on the irradiated object, so that it can act on the headlight of a high speed vehicle.

As described above, in the embodiment of the present invention, a high frequency resonant electronic ballast circuit having an effect of directly lighting a high voltage discharge lamp in applying a HID lamp having a high luminous efficiency and a long life to an automobile lighting system can be provided. .

Claims (7)

A power supply unit for supplying power; A booster circuit for boosting power from the power supply unit; A high frequency resonant converter circuit for converting the output of the booster circuit into a high voltage AC voltage; A discharge lamp configured to emit light by receiving the output of the high frequency resonant converter circuit; A square wave generator using the output of the booster circuit as an input and generating a square wave, a constant voltage controller for supplying a stabilized DC voltage, and a juice switching element in the high frequency resonant converter circuit using an output transformer of the square wave generator. And a zero voltage switching driving circuit for zero voltage switching. The high frequency resonant electronic ballast circuit of claim 1, wherein the booster circuit boosts the applied DC low voltage of about 12V or 24V by about 2.0 to 30 times. The booster circuit according to claim 1, further comprising: an inductor for accumulating magnetic energy by a switching action of the switching element; A diode for rectifying the accumulated energy to a DC high voltage; A feedback circuit for feeding back a DC high voltage which is an output voltage of the booster; A triangular wave generator for outputting a triangular wave for controlling the booster output; And a comparator configured to compare the output value of the feedback circuit to drive a switching element. 4. The circuit of claim 3, wherein the feedback circuit comprises: a detector for detecting the magnitude of the booster output voltage and inverting polarity; An adder which adds a reference voltage and the detector output voltage to output an error voltage; And a proportional integrator configured to be proportional to a booster output voltage and maintain a stable operation even in a high frequency switching frequency range using the error voltage as an input. The high frequency resonant converter circuit according to claim 1, further comprising: an upper end of a juice switching element having the booster output voltage as an input; Juice lowering device bottom; High frequency resonant electronic ballast circuit characterized by consisting of a high frequency resonant circuit. 2. The high frequency resonant converter circuit of claim 1, wherein the high frequency resonant converter circuit is composed of an insulator, an insulator, and an insulator for setting the voltage ratio arbitrarily while electrically insulating the high voltage discharge lamp in order to turn on the inductor for the series resonance operation. High frequency resonant electronic ballast circuit. The high frequency resonant converter circuit of claim 1, wherein the high frequency resonant converter circuit includes a ratio of a driving transformer, a winding of the driving transformer, to maintain a switching operation by a positive feedback action of a resonance current in a high frequency resonant circuit including a discharge lamp. A high frequency resonant electronic ballast circuit, wherein a capacitor in a square wave generator is charged by regenerating a predetermined amount of resonant current through a diode in a drive signal controller.