CN1879455A - The apparatus and method for synchronous lighting by one ballast with two bulb - Google Patents

Abstract

This invention discloses an apparatus and method for simultaneously lighting two lamps using a single ballast. To allow one ballast, rather than two, to control two bulbs or a left and right lamp in an M (High Intensity Discharge) system used as vehicle headlights, the apparatus comprises: an inverter with sensing function; a step-down circuit breaker for controlling an unbalanced load between the two bulbs; and an exciter including a double-layer foil with a capacitor layer shape, thereby controlling the unbalanced load between the two lamps or bulbs, making it possible to simultaneously light two lamps or a left and right lamp using a single ballast.

Description

Device and method for simultaneously lighting two light bulbs with one ballast

technical field

The present invention relates to a device for lighting two bulbs with one ballast and its control method, more particularly, to a device for lighting two bulbs with one ballast and its control method, wherein in order to allow one ballast to control Two bulbs or left and right lamps, provided with two inverters, a step-down circuit breaker and an exciter comprising a double foil in the shape of a capacitive layer to control the flow between the two bulbs or left and right lamps Unbalance the load to light both bulbs or left and right lights at the same time.

Background technique

The ballast usually provides the high starting voltage needed to start the lamp and limits the current in the lamp to a predetermined value after the lamp is switched on. Therefore, it is necessary for the ballast to provide a high-voltage excitation pulse for lighting the lamp, and provide an instantaneous current and a cut-off voltage suitable for switching the discharge state after excitation, thereby further suitable for quickly turning on the lamp in the case of a cold start. lighting control. In addition, uniform (consistent) power must be supplied to the lamp to obtain a stable light output and long lifetime under steady state conditions. However, it is difficult to control such lamp power and design a controller because the lamp's bulb voltage varies greatly from lamp to lamp and rises as the lamp continues to operate.

In the prior art, in order to run the two HID (High Intensity Discharge, high-intensity discharge) lamps on the vehicle as the imbalance control target as described below, two ballasts are used to control the operation of the two HID lamps respectively. . However, since it is difficult to leave a space for installing two ballasts in the vehicle, and since two exciters for generating high voltage are provided at different positions, manufacturing costs increase and there are safety problems.

In addition, the left lamp and the right lamp installed in the front portion of the vehicle are under different conditions, so it is difficult for the uniformity of the internal bulb voltages of the bulbs to be precisely unified with each other. Therefore, in order to operate conventional HID lamps on a vehicle, each lamp needs to have a ballast, and the ballasts need to be controlled individually. In this case, there is a problem in the structure of the vehicle lamp, the up lamp and the down lamp of the vehicle are constructed together, and the up lamp and the down lamp are composed of conventional halogen lamps and HID lamps, respectively.

Contents of the invention

Therefore, the present invention has been made in view of the above-mentioned problems. The object of the present invention is to provide a device for simultaneously lighting two independent light bulbs or left and right lamps with one ballast, which is used in the HID (High Intensity Discharge) system of automobile headlights, wherein, Two inverters, a step-down circuit breaker, and an exciter including a double-layer foil in the shape of a capacitive layer are provided to control unbalanced loads between two bulbs or left and right lamps, simultaneously lighting both Light bulb or left light and right light.

According to an aspect of the present invention, the above and other objects of the present invention can be achieved by providing a device for simultaneously lighting two lamps with one ballast. The device includes: a flyback converter; a power supply unit; a PWM controller; a first and a second gate driver; a full-bridge inverter including a first inverter and a second inverter, the first inverter The 5th, 7th, 8th, and 11th sense resistors coupled to one side of the full-bridge inverter detect and sense the output voltage and output current output when the left lamp is operating, the second The inverter detects and senses the output voltage and output current output when the right lamp operates through the 12th, 14th, 15th, and 16th sense resistors; the controller, for receiving the input voltage from the power supply unit, receives The input current through the 10th resistor to maintain the output power at a uniform level, thereby stabilizing the power supplied to each load, and is used to detect the output voltage and output when the first and second inverters are operating current to control the unbalanced load between the two lamps; a step-down circuit breaker, connected to one side of the controller, which first regulates power to the bulb with the higher impedance of the two bulbs to the reference After power, control the voltage of the other bulb with lower impedance among the two bulbs, so as to control the unbalanced load generated when the two lamps are initially operated; the exciter, connected to one side of the first and second inverters, so The igniter described above is capable of applying a high voltage pulse to both the left and right lamps simultaneously, thereby energizing both lamps in cold start or hot start state with one high voltage energy.

According to another aspect of the present invention, there is provided a method of simultaneously lighting two lamps with one ballast, comprising the steps of: a) performing voltage control by measuring the values of the input and output voltages, and then enabling the flyback conversion The load rate at the ballast is maximized and a high voltage is applied to the secondary side of the transformer until the lamp starts to ignite so that the lamp cannot start to ignite for a period of time after power is supplied to the ballast inside, run the igniter; b) allow the first and second gate drivers to simultaneously light two independent lamps or lamps with two bulbs in a single body under the control of the controller; c) perform current control to allowing the ballast to flow a large amount of current with free movement of charge during the lamp ignition start period and the lamp transition period, thereby stabilizing DC operation; and d) performing power control to allow the ballast The controller measures the input voltage and current and the output voltage and current until the lamp enters a steady state after the switching period to control all voltages and currents to keep the lamp in a normal lit state.

Description of drawings

The above and other objects, features and advantages of the present invention will be more clearly understood by understanding the following detailed description with reference to the accompanying drawings, wherein:

Fig. 1 is a circuit diagram showing a device for lighting two bulbs simultaneously with one ballast according to the present invention;

Fig. 2 is a graph showing the operation of a device for lighting two bulbs simultaneously with one ballast according to the present invention;

Figure 3 illustrates the operation of a flyback converter when performing voltage control according to one embodiment of the present invention;

Figure 4 illustrates the operation of a flyback converter when current control is performed according to one embodiment of the present invention;

Figure 5 shows an exciter with a "Π" coil structure according to an embodiment of the present invention;

Figure 6 shows an exciter with a double-layer coil structure according to an embodiment of the present invention;

Figure 7 shows an exciter with a string coil structure according to one embodiment of the present invention;

Figure 8 shows a flow chart of a method for simultaneously lighting two bulbs with one ballast according to the present invention; and

FIG. 9 shows a detailed flow chart of the simultaneous lighting control method in the method of using one ballast to simultaneously light two bulbs according to the present invention.

Detailed ways

Now, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a circuit diagram showing a device for simultaneously lighting two bulbs using one rectifier according to the present invention. As shown, the device includes a flyback converter 10, a full bridge inverter 20/30, a controller 40, a PWM (Pulse Width Modulation) controller 16, a buck circuit breaker 15, gate drivers 23 and 33, and igniter 70 .

Specifically, in order to simultaneously turn on the left lamp 50 and the right lamp 60 of the vehicle, the full-bridge inverters 20/30 include a first half-bridge inverter 20 for operating the left lamp 50 and a second half-bridge inverter for operating the right lamp 60. Two half-bridge inverters 30 .

The structures and operations of the PWM controller 16 and the gate circuits 23 and 33 are well known in the art, so their detailed descriptions are omitted here.

The flyback converter 10 is connected to an input voltage detector 12, an input current detector 13, a transformer T1, and diodes D1, D2, D3 and D4. The input voltage detector 12 is connected to the circuit on the side of the flyback converter 10 to detect the input voltage input from the battery and the generator as the vehicle power source based on the predetermined resistivity between the register R3 and the register R4. The input current detector 13 is connected to the circuit on one side of the input voltage detector 12 to detect the input current input to the switching transistors S3 and S4, which are turned on/on by the control signal of the PWM controller 16 during the initial operation. cut-off (on/off). Transformer T1 is connected to the circuit on top of it, stepping up and outputting battery and generator voltage V+ and V- with switching transistors S3 and S4 on/off. Diodes D1 and D2 rectify the high voltage of 1500 volts from transformer T1 and provide this voltage to exciter 70 . The diodes D3 and D4 rectify the DC voltage output from the transformer T1 (which varies with the lighting state of the lamp), and supply the DC voltage to the first and second inverters 20 and 30 . An electrolytic capacitor C5, resistors R6 and R11, and an electrolytic capacitor C6 are connected in parallel between the ground and the cathode of the diode D3. Similarly, an electrolytic capacitor C8, resistors R13 and R16, and an electrolytic capacitor C9 are connected in parallel between the ground and the cathode of the diode D4.

The input voltage detector 12 detects whether a uniform voltage of 12 volts is supplied to each load. By using the sense resistor R10 , the input current detector 13 detects whether a uniform current flows in the transformer T1 according to the current command provided by the controller 40 .

The first inverter 20 includes a sense resistor coupled to a portion of the flyback converter 10 so as to have the sensing function of controlling either of two independent lamps or lamps with two bulbs. Any one bulb works as the left lamp 50 . As shown in FIG. 1, the first inverter 20 includes sense resistors R5, R7, and R8, an electrolytic capacitor C7, and a sense resistor R11. The first inverter 20 is connected to an output voltage detector 22, an output current detector 21, and switching transistors S1, S2, S5, and S6. The output voltage detector 22 is connected between the two sense resistors R7 and R8 to detect the output voltage of the left lamp 50 when it is operated. By using the sense resistor R11, the output current detector 21 detects the DC current flowing into the lamp through the igniter 70 when the lamp is initially operated. The switching transistors S1 , S2 , S5 and S6 are turned on/off according to a driving signal output from the gate driver 23 .

The second inverter 30 includes a sense resistor coupled to a portion of the flyback converter 10 so as to have the sensing function of controlling either of two independent lamps or lamps with two bulbs. One light bulb works as the right light 60 . As shown in FIG. 1 , the second inverter 30 includes sense resistors R12 , R14 , and R15 , an electrolytic capacitor C10 , and a sense resistor R16 . The second inverter 30 is connected to the output voltage detector 32, the output current detector 31, and the switching transistors S7, S8, S9, and S10. The output voltage detector 32 is connected between the two sensing resistors R14 and R15 to detect the voltage output from the right lamp 60 when it operates. By using the sense resistor R16, the output current detector 31 detects the DC current flowing into the lamp through the igniter 70 when the lamp is initially operated. The switching transistors S1 , S2 , S5 , and S6 are turned on/off according to a driving signal output from the gate driver 33 .

The characteristic of the controller 40 is to include a PWM generator, a lamp regulated power supply, a lamp temperature compensator, and an overall protection circuit. The controller 40 receives the input voltage from the power supply unit, and controls the voltage supplied to each load by maintaining the input current at a consistent or constant level through the resistor R10 during the initial operation stage. In addition, the controller 40 controls the unbalanced load between the two lamps or light bulbs by detecting the output current and output voltage generated when the first and second inverters 20 and 30 operate.

As shown in FIG. 1 , the controller 40 is connected to the input voltage detector 12 , the input current detector 13 , the output current detector 21 , the output voltage detectors 22 and 32 , the PWM controller 16 , and the gate driver 23 . The input voltage detector 12 is used to regulate the initial voltage to a uniform or constant voltage of 12 volts. The input current detector 13 is connected to one side of the input voltage detector 12 to obtain a uniform voltage according to a current command value provided by the controller 40 . The output current detector 21 is used to control the DC current in the igniter 70 which varies according to the energized state of the lamp. The output voltage detectors 22 and 32 detect output voltages output when both the left lamp and the right lamp are operated, respectively. The PWM controller 16 allows the flyback converter 10 to output a predetermined level of DC voltage and a DC voltage that varies according to the firing state of the lamp. The gate driver 23 provides a gate signal as a control signal to allow the first and second inverters 20 and 30 to output a rectangular AC voltage.

The step-down circuit breaker 15, which is a buck converter, is connected to the controller 40, and operates in the following manner. In order to control the unbalanced load that occurs when the lamp is initially operated, the step-down circuit breaker 15 first regulates the power of the lamp with the higher impedance among the two lamps to the reference power, and then controls the lamp voltage of the other lamp with the lower impedance, Thereby keeping the power of the two bulbs consistent.

According to the present invention, the exciter 70 has a main stage in the form of a capacitive layer and two secondary parts on one side of the main stage, and the two secondary parts are connected to the left lamp 50 and the right lamp 60, respectively.

Specifically, the exciter 70 with one primary coil and two secondary coils is based on the following coil pattern. As shown in FIG. 5 , the primary portion 71 is formed on one side of the exciter 70, and two secondary portions 72 and 73 are vertically arranged on one side of the primary portion 71, so that the primary portion and the two secondary portions have "Π" shape. Alternatively, as shown in FIG. 6 , the primary portion 71 is formed on one side of the exciter 70, and two secondary portions 72 and 73 form a double layer on one side of the primary portion 71, so that the secondary portion 72 One of them is arranged on the inside, the other secondary part 73 is arranged on the outside. Further, alternatively, as shown in FIG. 7 , the primary portion 71 is formed on one side of the exciter 70 , and the two secondary portions 72 and 73 are continuously arranged in a row on the side of the primary portion 71 .

One of the two secondary parts configured in the form described above is connected to the left lamp 50 and the other to the right lamp 60, so that either of the two lamps or either of the left and right lamps can be controlled by only one lamp. ballast control without the need for two ballasts.

Preferably, a coil made of aluminum foil with high thermal and electrical conductivity and high corrosion resistance in air is used.

Similar to the device in the prior art that uses two ballasts to light two lamps at the same time, the device that uses one ballast to light two lamps according to the present invention includes: a flyback converter 10, a full-bridge inverter 20 /30, the power supply unit 11, the PWM controller 16 and the gate drivers 23 and 33 are as described above and have the following features. The flyback converter 10 includes an input voltage detector 12 , an input current detector 13 , a buck circuit breaker 15 and output current detectors 21 and 31 . The full bridge inverters 20 / 30 include a first inverter 20 with a sensing function for operating the left lamp 50 and a second inverter 30 with a sensing function for operating the right lamp 60 . In addition, the foil-shaped exciter 70 in the device comprises two secondary parts 72 and 73 formed as a double layer in the shape of a capacitive layer so as to connect the exciter to the left lamp 50 and the right lamp 60 .

Now, the operation of the apparatus according to the present invention for simultaneously lighting two lamps with one ballast will be described.

As shown in Figure 2, the working state of the lamp is divided into: the breakdown time period when the discharge starts, the glow discharge time period when the glow discharge occurs due to ion collision, and the light-arc time period when the lamp changes from the glow discharge state to the arc discharge state. A transition time period, and an arcing time period in which arcing is induced by thermionic emission.

First, during the breakdown period at the beginning of the discharge, a high voltage pulse for excitation is applied across the two electrodes of the lamp to break the internal insulating state of the lamp. In order to break the internal insulation state, in the case of cold start (initial excitation), a voltage of 2KV is required, and in the case of hot start (re-excitation), a voltage of 25KV is required. The lamp needs to be cooled to avoid the necessity of applying a high excitation voltage in case of a hot start, but it typically takes 10 minutes or more to return the lamp to the cold state under natural cooling conditions. Therefore, the present invention employs an exciter 70 capable of outputting a voltage of 25KV or higher.

Next, in a glow discharge period in which discharge occurs due to ion collision, a voltage for maintaining a glow discharge state is applied to the lamp after the lamp is energized. In the present invention, before the lamp is ignited, a voltage of about 600V is applied to the lamp, so that the lamp remains in a glowing state after ignited.

Again, a take-over current circuit is provided for the glow-to-arc transition period when the lamp is switched from the glow discharge state to the arc discharge state after the lamp is ignited. The lamp will not light unless sufficient take-over current is supplied to the lamp. This is because, immediately after the lamp has been switched to the arcing state, the lamp voltage is reduced while the lamp is kept in the arcing state by means of the current supplied by the ballast. Therefore, in the present invention, the takeover current circuit allows current to flow to the lamp until sufficient current is supplied to the lamp by the ballast.

Again, during the arc discharge period in which thermionic emission induces arc discharge, after the lamp has transitioned from the glow discharge state to the arc discharge state, the temperature and pressure inside the lamp increase due to the power supplied by the ballast . At this point, the voltage and optical output of the lamp also increased to a steady state. Since the current supply in this working period determines the heating time of the lamp and determines the optical output response characteristics of the lamp in the switching state, so under the control of the controller of the present invention, the power of the lamp is adjusted to the desired required power.

Finally, in order to achieve a predetermined optical output in a steady state, the power supplied to the lamp is uniformly controlled to a rated value, thereby avoiding lamp flicker and reduction of lamp life.

Referring to the above description of the operation of the device, the operation of the controller 40, the step-down circuit breaker 15, the first and second inverters 20 and 30, and the exciter 70 in the device according to the present invention will be described in detail below.

First, referring to FIG. 1, the operation of the controller 40 is described. The controller 40 features a PWM generator, lamp power stabilizer, lamp temperature compensator, and overall fault protection circuitry. The controller 40 receives input voltage and input current from the battery and the generator, respectively, and maintains the output power at a uniform level to control the power supplied to each load and to control the power supplied to the first and second inverters 20 and 30. output voltage and output current. Particularly, when the left lamp 50 and the right lamp 60 work, the controller allows the output voltage detectors 22 and 32 to detect the output voltage between the sensing resistors R7 and R8 and the output voltage between the sensing resistors R14 and R15 . If it is detected that the unbalanced load in one of the two lamps has increased, the controller 40 increases the system short capacity to maintain the output voltage at a uniform level and control the unbalanced load.

In addition, when the step-down circuit breaker 15 works, the controller 40 generates a control signal to control the uniform level of input voltage and input current input to the step-down circuit breaker 15, so as to control the voltage between the two lamps when the lamps initially work. resulting in an unbalanced load.

Further, the controller 40 controls the gate driver 23 of the first inverter 20 and the gate driver 33 of the second inverter 30 to simultaneously turn on the left lamp and the right lamp (50 and 60).

The first inverter 20 is now described. Using four switches S1, S2, S5, and S6, the first inverter 20 is operated by alternately repeating switching a pair of switches. That is, from the operating waveform of the switch, it can be seen that the switch has the same voltage as the input voltage, but from the prime voltage waveform of the transformer, the maximum value is twice the maximum value of the half bridge. times. This means that the output voltage is doubled and it is possible to obtain twice the output of the half-bridge under the same conditions. That is to say, since the voltage is inversely proportional to the current, the input current becomes the switch current, so the intensity of the output current of the inverter is half of the intensity of the switch current under the same output conditions.

The current in the first inverter 20 circuit is given by the following equation:

Equation 1

$\mathrm{<span\; class="notranslate">\; I</span>}<span\; class="notranslate">\; =</span><span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; V</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}\frac{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; T</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&tau;</span>}}}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; T</span>}}{\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&tau;</span>}}}}\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; t</span>}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; V</span>}}{\mathrm{<span\; class="notranslate">\; R</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; e</span>}}^{\frac{<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; t</span>}}{\mathrm{<span\; class="notranslate">\; \&tau;</span>}}}<span\; class="notranslate">\; )</span>$

The switching operation of the circuit is performed in the sequence (S1, S6) and (S2, S5), the signal has a rectangular waveform.

In this way, the first inverter 20 receives the DC voltage of 20-100V output by the flyback converter 10 and converts the DC voltage into a rectangular AC voltage of 150-200 Hz. The first inverter 20 has a sense resistor coupled to one side thereof, thereby providing a sensing function, allowing either one of two independent lamps or one bulb in an integral lamp composed of two bulbs to act as the left Lamp 50 works. That is, when the lamp is on, the first inverter 20 senses a voltage of 50V at a predetermined ratio through the sense resistors R5, R7, and R8 and the sense resistor R11, and passes it through the gate driver 23 The current supplied to the left lamp 50 or from the activator 70 to the sense resistor R11 is reduced as the lamp impedance increases, thereby reducing the sensed intensity to control the unbalanced load between the two lamps.

Here, the output voltage detector 22 detects the output voltage between the sensing resistor R7 and the sensing resistor R8, and the driving signal output by the gate driver 23 turns on/off the transistors S1, S2, S5, and S6 to light the left lamp 50.

Next, the operation of the first inverter 20 is described below. In the same manner as the first inverter 20, the second inverter 30 receives the 20-100V DC voltage output by the flyback converter 10, and converts the DC voltage into a rectangular AC voltage of 150-200 Hz. The second switch 30 has a sense resistor coupled to one side thereof, thereby having a sensing function, allowing either of the two independent lamps or a lamp integral with two bulbs to operate as the right lamp 60 . That is, when the lamp is operating, the second inverter 30 senses an output voltage of 50V at a predetermined ratio across the sensing resistors R12, R14 and R15 and the sensing resistor R16, and applies it through the gate driver 33. to the right lamp 60, or reduce the current flowing from the energizer 70 to the sense resistor R16 as the lamp impedance increases, thereby reducing the sensed intensity to control the unbalanced load between the two lamps.

Here, the output voltage detector 32 detects the output voltage between the sensing resistor R14 and the sensing resistor R15, and the driving signal output by the gate driver 33 turns on/off the transistors S7, S8, S9, and S10 to Turn on the right lamp 60 .

Next, the operations of the energizer 70 and the step-down circuit breaker 15 are described below.

When the voltage supplied by the power supply unit reaches a predetermined voltage of 400V˜600V, the voltage is supplied to the exciter 70 through a self-transferred electronic spark gap. The igniter 70 then initiates the discharge of the lamp by generating the discharge current required to cause the lamp to initially glow discharge. At this time, the inverter opens a current channel in one direction to continuously provide power, and the two secondary parts according to the present invention are respectively connected to the two lamps to provide the voltage required for discharge.

However, since the voltage at that time (before the inverter) plateaus is constant, the bulb with the lower impedance draws more current and the bulb with higher impedance draws less, so unbalanced power needs to be supplied to the bulbs .

In order to avoid unbalanced power, the invention equalizes the power supplied to the two bulbs through the step-down circuit breaker 15, which controls the bulb with the lower impedance after regulating the power to the bulb with the higher impedance to the reference power. The voltage of the bulb, thus making it possible to achieve the rated value.

That is, the controller 40 transmits a control signal through the PWM controller 16 when a power imbalance occurs between the two lamps when the lamps are initially operated. The control signal from the PWM controller is used to control the predetermined level of input current and input voltage input to the step-down circuit breaker 15 to control the lamp with lower impedance after adjusting the power of the lamp with higher impedance to the reference power. Lamp voltage, thereby controlling the unbalanced load formed between the two lamps.

Referring to FIG. 8 , a control method for simultaneously lighting two lamps with one ballast according to the present invention will be described.

First, in order to enable the exciter to operate during the period of time when the lamp is not started after power is supplied to the ballast, the controller performs voltage control operations in such a way that it measures the values of the input and output voltages, and then converts To maximize the load rate at the transformer, a high voltage is applied to the secondary side of the transformer until the lamp starts ("voltage control step" S110).

In one embodiment of the present invention, as shown in FIG. 3 , the 12V supply voltage of a battery used as a vehicle power supply is increased and stabilized at a flyback converter. At this time, if the PWM controller control signal output by the controller 40 turns off the transistors S3 and S4, the input current flowing into the primary side of the transformer can no longer flow, so that no magnetic field is induced in the core. On the secondary side of the transformer, the polarity of the electromotive force Es is reversed while the output diode D is biased in the forward direction. At this time, the energy induced on the secondary side of the transformer core conversely induces a voltage on the secondary side according to the turns ratio of the primary coil and the secondary coil. The reflected voltage V _fb is called "flyback voltage" and can be obtained by the following equation:

Equation two

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; fb</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; S</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; S</span>}}}{\mathrm{<span\; class="notranslate">\; E.</span>}}_{\mathrm{<span\; class="notranslate">\; S</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; P</span>}}}{{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; S</span>}}}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; out</span>}}<span\; class="notranslate">\; +</span>{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; f</span>}}<span\; class="notranslate">\; )</span>$

Here, when the transistors S3 and S4 are turned off, the voltage V _fb is applied between the drain and the source, the withstanding voltage is determined, and the duty ratio is maximized to perform voltage control, thereby turning the high voltage applied to the secondary side of the transformer.

Next, under the control of the controller, the gate drivers 23 and 33 simultaneously light up two independent lamps or a lamp having two bulbs in a single body (S120).

As mentioned above, the device according to the invention comprises: two inverters, a step-down circuit breaker for controlling the unbalanced load between the two lamps, an exciter comprising a double foil in the shape of a capacitive layer, so that it is possible to utilize a The ballast lights both bulbs simultaneously or a left lamp and a right separate lamp.

In an embodiment of the present invention, as shown in FIG. 9, the vibration of the power supplied from the power supply unit is checked (S200), and then the condition of the bulb is checked whether it is a hot start condition or a cold start condition (S210). If the condition of the bulb is a hot start condition, the full-bridge converter duty ratio D ₂ can be determined by the following equation ( S220 ).

Equation 3

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; out</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 2</span>}}}{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

Among them, D ₂ represents the load rate of the full-bridge converter under the condition of hot start.

On the other hand, if the lamp condition is a cold start condition, then the full-bridge converter duty rate D ₁ can be determined by the following equation (S230).

Equation 4

${\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; out</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; (</span>\frac{{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; D.</span>}}_{\mathrm{<span\; class="notranslate">\; 1</span>}}}{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; ,</span>$

Among them, D ₁ represents the load rate of the full-bridge converter under the condition of cold start.

The duty ratios _D1 and _D2 determined in this manner are added to determine an optimum duty ratio to provide a DC voltage in the range of 400V to 600V for operation of the first and second inverters (S240).

The DC voltage generated in this way is automatically supplied to the exciter via the electronic spark gap. As the DC voltage is supplied to the exciter, a voltage required for an initial glow discharge is generated, and the discharge is started (S250). Thus, the bulbs are turned on at the same time (S260).

At this time, if an unbalanced load occurs between the two bulbs, the powers of the left and right lamps are compared with each other (S270).

If one of the left and right lamps has high power, the controller controls the step-down circuit breaker to operate so that after the power of the bulb with higher impedance is first adjusted to the reference power, the power on the bulb with lower impedance The voltage is controlled so that the power of the two lamps is equal (S290). The first inverter detects the output voltage and output current output when the left lamp is operating, and senses the output voltage and output current through sense resistors R5, R7, and R8 and sense resistor R11, however, the second The inverter detects the output voltage and output current output when the right lamp operates, and senses the output voltage and output current through the sense resistors R12, R14, and R15 and the sense resistor R16, thereby performing the first and second Alternate control between inverters (S300).

If one of the left lamp and the right lamp has small power, alternate control between the inverters as described above is performed in the above-mentioned manner (S280) to keep both lamps lit with uniform constant power (S310).

Next, the ballast causes a large amount of current to flow with free movement of charges during the bulb lighting start period and the bulb transition period, thereby stabilizing the DC operation ("current control step" S130).

In one embodiment of the present invention, as shown in FIG. 4, if the transistors S3 and S4 are turned on, V _in is directly provided to the primary side of the transformer with an inductance L _p . Here, assuming that the input voltage is an ideal DC voltage, the conduction time of the transistors S3 and S4 is equal to the duty factor D of the switching period T. At that time, the input voltage increases to the value given by the following equation:

Equation 5

${\mathrm{<span\; class="notranslate">\; i</span>}}_{\mathrm{<span\; class="notranslate">\; i</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; L</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}}}{<span\; class="notranslate">\; \&Integral;</span>}_{\mathrm{<span\; class="notranslate">\; 0</span>}}^{\mathrm{<span\; class="notranslate">\; t</span>}}{\mathrm{<span\; class="notranslate">\; V</span>}}_{\mathrm{<span\; class="notranslate">\; L</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; dt</span>}$

In this equation, as the input current i _in (t) increases, the magnetic energy of the transformer increases. If a changing input current i _in (t) flows through the main coil of the transformer, a magnetic flux Φ(t) is generated in the transformer core, and according to Faraday's law, the electromotive force induced at both ends of each coil can be obtained by the following equation :

Equation 6

${\mathrm{<span\; class="notranslate">\; E.</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; p</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; the\; s</span>}}\frac{\mathrm{<span\; class="notranslate">\; d\&Phi;</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; t</span>}<span\; class="notranslate">\; )</span>}{\mathrm{<span\; class="notranslate">\; dt</span>}}$

That is, if an electromotive force E _p is induced on the primary side, an electromotive force E _s of opposite polarity is induced thereon, so that the output diode D is reverse biased. Therefore, the energy of the input voltage is only accumulated in the core without being transferred to the secondary side, and only the energy of the output capacitor is supplied to the load.

The input current increases in such a way that when the input current does not increase any more (t=DT), the input current has a maximum value so that DC operation can be stabilized.

Then, after the switching period until entering a steady state, the ballast measures the input voltage and current and the output voltage and current, and controls all voltages and currents so that the lamp is kept on normally ("power control step" S140).

In one embodiment of the present invention, if power is supplied to the first inverter 20, and the left lamp 50 is normally lit, then the first inverter 20 passes through sense resistors R5, R7, and R8 and The sense resistor R11 detects and senses the output voltage and output current generated by the high voltage of the igniter, which varies with the energized state of the left lamp 50 .

At this time, in order to keep the left lamp normally lit through the step-down circuit breaker 15, the controller 40 compares the value of the output current of the transformer T1 with the predetermined current value, and if the comparison value is not in the predetermined range, then controls the PWM control signal. frequency and pulse width, so that the output current of transformer T1 remains uniform.

In the same manner as the first inverter 20, if energy is supplied to the second inverter 30, the second inverter 30 detects and Sensing the output voltage and output current generated by the high voltage of the igniter, wherein the high voltage of the igniter varies with the energizing state of the right lamp 60 .

At this time, in order to keep the right lamp normally lit through the step-down circuit breaker 15, the controller 40 compares the output current value of the transformer T1 with the predetermined current value, and if the comparison value is not within the predetermined range, then controls the PWM control signal. Frequency and pulse width, so that the output current of transformer T1 remains uniform.

As mentioned above, the device according to the invention comprises: two converters, a step-down circuit breaker, and an exciter comprising a double layer foil in the shape of a capacitor layer, thereby effectively controlling two light bulbs and two left and right lamps. The unbalanced load between lamps makes it possible to simultaneously light two bulbs or left and right lamps with one ballast.

Industrial Applicability

From the above, it can be understood that the apparatus for simultaneously lighting two lamps using one ballast and the control method thereof according to the present invention have the following advantages. Compared with the conventional device for separately controlling the HID lamp as the unbalance control target with two ballasts on the vehicle and the control method thereof, the present invention can reduce the product cost, control the unbalanced load, and further realize size reduction and weight reduction. Relief, simplified circuit structure, thereby improving reliability.

Although the preferred embodiments of the present invention have been described for illustrative purposes, those skilled in the art will understand that various changes, additions and and permutations are possible.

Claims (9)

1. A device for simultaneously lighting two bulbs with one ballast, comprising: flyback converter; power supply unit; PWM controller; first and second gate drivers; a full-bridge inverter comprising a first inverter and a second inverter, the first inverter sensing The resistor and the 11th sense resistor detect and sense the output voltage and output current output when the left lamp is operating, and the second inverter passes through the 12th, 14th, 15th, and 16th sense resistors Detect and sense the output current and output voltage output when the right lamp is working; a controller for receiving an input voltage from the power supply unit and an input current through the 10th resistor to maintain the output power at a consistent level, thereby stabilizing the power supplied to each load, and for detecting the an output voltage and an output current output by the first and second inverters in operation to control an unbalanced load between said two bulbs; a step-down circuit breaker connected to one side of the controller, the step-down circuit breaker controlling the bulb with the lower impedance after first regulating the power of the bulb with the higher impedance of the two bulbs to a reference power the bulb voltage of the bulbs to equalize the wattage of the two bulbs to control unbalanced loads caused when the two bulbs are initially operated; and an exciter connected to one side of the first and second inverters, the exciter is capable of simultaneously applying a high voltage pulse to the left lamp and the right lamp so that the two lamps are cold-started or These two lamps are ignited with high voltage electricity during hot start. 2. The apparatus of claim 1, wherein the first inverter is connected to a first output voltage detector located between the 7th and 8th sense resistors , used to detect the output voltage when the left lamp is working, Wherein, the first inverter is also connected to a first output current detector, and the first output current detector is used to detect the DC current flowing through the exciter when the left lamp initially operates, and Wherein, the first inverter is also connected to the first, second, fifth, and sixth switching transistors, and these transistors are turned on/off by the driving signal output by the first gate driver. 3. The apparatus of claim 1, wherein the second inverter is connected to a second output voltage detector located between the 14th and 15th sense resistors interval, used to detect the output voltage of the right lamp when it is working, Wherein, the second converter is also connected to a second output current detector, and the second output current detector is used to detect the DC current flowing through the exciter when the right lamp initially works, and Wherein, the second converter is also connected to the seventh, eighth, ninth, and tenth switching transistors, and the transistors are turned on/off by the driving signal output by the second gate driver. 4. The apparatus of claim 1, wherein the controller is connected to an input voltage detector, an input current detector, the PWM controller, first and second output current detectors, and the first and the second gate driver. 5. The device according to claim 1, wherein the exciter includes a primary portion formed on one side thereof, and two secondary portions vertically arranged on one side of the primary portion, so that the primary stage section and the secondary section has shaped shape. 6. The device according to claim 1, wherein the exciter includes a primary portion formed on one side thereof, and two secondary portions forming a double layer on one side of the primary portion, so that the secondary One of the stages is on the inside and the other is on the outside. 7. The device according to claim 1, wherein the exciter includes a first part formed on one side thereof, and two second parts formed continuously in a row in a row on one side of the first part. 8. A method for simultaneously lighting two bulbs with one ballast, comprising the following steps: a) By measuring the values of the input and output voltages, performing voltage control, and then maximizing the load rate at the flyback converter, a high voltage is applied to the secondary side of the transformer until the light bulb starts to glow, so that the igniter operating during a period when the bulb does not start to emit light after power is supplied to the ballast; b) allow the first and second door drivers to simultaneously light two independent bulbs or a lamp with two bulbs in a single body under the control of the controller; c) performing a current control operation to allow the ballast to allow a large amount of current to flow with free movement of charges during the lighting start period of the bulb and the transition period of the bulb, thereby stabilizing the DC operation; and d) Perform power control operations to allow the ballast to measure input voltage and current and output voltage and current until the ballast enters a steady state after a transition period, then control all voltages and currents to The bulb remains in a normally lit state. 9. The method according to claim 8, wherein said step b) comprises the steps of: b-1) Check the vibration of the power supplied by the power supply unit; b-2) Check if the bulb is in a hot start condition or a cold start condition; b-3) If the light bulb is under the hot start condition, then determine the load rate of the first full-bridge converter; b-4) If the light bulb is under the cold start condition, then determine the load rate of the second full-bridge converter; b-5) determining an optimum duty ratio by adding the first and second duty ratios, and then applying a DC voltage in the range of 400V to 600V suitable for operation of the first and second inverters; and b-6) allowing said DC voltage to be supplied to said exciter so that said exciter generates the voltage required for an initial glow discharge, thereby initiating said discharge; b-7) Simultaneously lighting the light bulb by ignition of the igniter; b-8) When the corresponding light bulbs are lit at the same time, compare the corresponding power of the left lamp and the right lamp; b-9) If one of the left and right lamps has a small power, then allow the first inverter to sense and sensing the output voltage and output current output when the left lamp is in operation, and allowing the second inverter to detect and sense all output voltage and output current output when the right lamp is in operation, thereby performing alternate control between the first and second inverters; b-10) If one of the left lamp and the right lamp has high power, the controller is allowed to control the step-down circuit breaker to work, so that the power of the bulb with the larger impedance among the two bulbs is first adjusted to After the power is referenced, the bulb voltage of another bulb with a smaller impedance is controlled, so that the power of the two bulbs is consistent; b-11) performing alternate control between the first and second inverters after completing the control of the step-down circuit breaker; and b-12) Keep both bulbs lit at consistent constant power.

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