TW200934075A - Inverter with variable resonance gain - Google Patents

Abstract

The invention provides an inverter with variable resonance gain. The inverter includes a pulse width modulation unit, a change-over switch unit, a resonance unit, a transformer and a frequency control unit. The switching button unit receives a DC power. The pulse width modulation unit generates a working cycle signal for driving the change-over switch unit to convert the DC power into a pulse power. The resonance unit converts the pulse power into a driving power, which is then converted by the transformer into an output power. It is characterized in that the resonance unit provides a starting voltage gain and a working voltage gain respectively at a starting frequency and a working frequency higher than the starting frequency, wherein the starting voltage gain is higher than the working voltage gain. As a result, a larger starting voltage gain is employed to generate an output power of higher voltage, so as to smoothly start the lamp tube set.

Description

200934075 IX. Description of the invention: [Technical field to which the invention pertains] A variable resonance gain converter is applied to an inverter that drives a lamp tube and adjusts a driving voltage by changing a resonance frequency. [Prior Art] The most important components of the liquid crystal display that are popular today are the polarizer and the backlight module. The backlight module must generate uniform light, and then pass through the polarizer to generate dialysis of different colors of light.

In order to enable the backlight module to achieve uniform light generation, the backlight module must have a plurality of lamps having a long life and an inverter for providing output power of the lamps, which can be adjusted by using the adjustment. The output power of the flow device is used to adjust the brightness of the lamp; and the conventional converter structure is as shown in FIG. 1 , including a power source i, a dimming signal source 6, a pulse width modulation unit 3, and a a switch unit 2, a vibration unit 4, a transformer 5, and a feedback unit 7, the power source 1 providing -DC power, the pulse width modulation unit 3 generating a duty cycle signal to drive the switch unit 2, The switching of the DC power through the switching unit 2 will form a pulsed power, and the resonant unit 4 obtains the pulsed power and converts it into a driving power through the resonance and converts the driving power by the transformer 5 to output an output power driving. a lamp group 9, and the dimming signal source 6 generates a dimming signal for the pulse width modulation unit 3 to adjust the duty cycle signal, and a duty eye to control the output power. The feedback unit 7 is sent to the pulse width adjusting element 3 on the secondary side of the transformer 5 to improve the function of the saga. The most basic knowledge of the contact is the follow-up test. Shouting duty ^duty (duty cycle) to determine the size of the output power; most of the customary use of the road to use as a driving circuit for the county module (four) full Lc-type vibration circuit, - general: circuit ^ most The base weight equivalent electric scale parameter _ , where % is the equivalent of _ word = vibration is the input voltage, LS is the vibration inductance, Cp is the spectral vibration capacitance, and the input voltage pulse power, W the two ends of the lamp Voltage 'the input voltage and the output voltage

//—1... j^c„ 200934075 Get it after finishing \ijco) vAja>) ^Ιαι/ψ风 • (1-2) ==, ^ίύηφ V&WKmplh^p)^ jed,s + RlM/t To simplify the above calculation, the other parameters are defined as follows

(1-3) Formula ❹ where Q is defined as the series resonance quality factor.

Where Z is the characteristic impedance of the vibration circuits. • (1-4) The formula (1-3) and (1-4) can be simplified as follows:

..... (1-5) and the transfer function gain curve of the LC resonant circuit is shown in Fig. 2_2; the conventional resonant circuit operates in a fixed frequency mode to form a fixed voltage gain through which the pulse width is applied. Modification grass · yuan 3 changes the duty cycle of the duty cycle signal (duty cyde) to adjust the brightness of the lamp group 9, the previous creation of the LC-type spectrum circuit, such as the Republic of China patent certificate No. 129〇7〇7 "Multi-lamp parallel drive circuit for liquid crystal display and its current sharing control method", in the prior art of FIG. 3 t 'variable (four) Ί 1 - the secondary side can be seen as an occupational inductance (Lr) and a resonant capacitance (Cr), and The spectral oscillator (Lr) and the proof capacitor (Cr) are used to generate a sine wave to convert power through the transformer T1; however, the above-mentioned dragon control by controlling the working cycle to control the brightness of the 200934075 causes the following defects: The duty dynasty (duty eyde) will guide the switch of the inverter to change the working state of _ (_ voltage switehing), resulting in additional losses. 2. Restricted by the switching factor of the switching unit, the duty cycle ratio of the rainbow duty signal has a limitation. Therefore, the inverter that drives the backlight module still needs to improve the above-mentioned lack. SUMMARY OF THE INVENTION In view of the above-described lack of inverters, the primary object of the present invention is to improve the provision of a modification that improves the mode of resonance, thereby achieving a characteristic of having a larger dimming system and coin switching. An inverter of the invention is a variable-hybrid converter, the converter comprising a pulse width modulation unit, a switching switch unit, a resonance unit, a transformer, a fresh control unit and a feedback unit. The switch unit obtains the DC power from the power source, and the pulse width modulation unit generates a duty cycle signal to drive the switch unit to convert the DC power into a pulse power, and the resonant unit converts the pulse power into a Driving power for converting the transformer into an output power to drive the lamp group connected to the inverter, wherein the pulse power is respectively at a starting frequency and an operating frequency higher than the starting frequency Forming a starting voltage gain and an operating voltage gain, wherein the starting voltage gain is greater than the working electric grinding gain, © to generate a higher voltage output power by a larger starting voltage gain to smoothly start the lamp group, and can borrow The resonant unit generates a different voltage gain by controlling the frequency of the pulsed power, and the pulse width adjustment is further adapted to the characteristics of the resonant unit. The frequency of the pulse power is adjusted by changing the frequency of the exclamation mark of the working cycle, and the frequency control unit can determine a reference voltage by acquiring the dimming signal and obtaining a feedback signal from the feedback element. a signal, the pulse width modulation unit determines the frequency of the duty cycle signal according to the reference voltage signal, and further enables the pulse power to have a starting frequency and an operating frequency higher than the starting frequency to achieve the effect of adjusting the brightness of the lamp group 8 [Embodiment] The detailed description and technical content of the present invention will now be described as follows: 200934075 ❹ Please refer to FIG. 3, which shows that the converter of the variable resonance gain has a pulse. Wide modulation unit 3, - switching unit 2, - vibration unit *, - = stream 5, - feedback order 7G 7 and - fresh control list; ^ 8, the pulse width modulation unit 3 generates - period signal Driving the switch unit 2, the switch unit 2 is driven by the power of the reading, and is driven by the reading and giving the DC power to the harmonized element 4 'Lin Xianyuan 4 the pulse electricity The conversion voltage H 5 is converted into an output power to drive the lamp group 9 , the frequency control unit 8 is connected to a dimming signal source 6 and the feedback unit 7 , the feedback unit 7 A feedback signal is obtained from the primary side of the transformer 5, and the dimming signal source 6 provides a dimming signal, and the frequency control unit = 8. And adjusting the frequency of the duty cycle signal according to the reference frequency signal, and adjusting the frequency of the pulse power according to the simple light reduction and the visual enchantment-reference fresh gift, wherein the resonant unit 4 Having a characteristic of resonance, wherein the frequency of the pulse power affects the voltage gain of the spectral power unit 4 to convert the driving power, and the pulse power is at a starting frequency and an operating frequency that is always the starting frequency, the requesting unit 4 Forming a starting voltage gain and an operating voltage gain corresponding to one of a starting frequency and an operating frequency, wherein the starting voltage gain is greater than the operating voltage gain to provide a higher voltage to activate the lamp group 9 to achieve the characteristic circuit As shown in FIG. 3, the resonant unit 4 includes a first damped inductor (Lr) 42, a second oscillating inductor (Lm) 43 and a resonant capacitor (Cs). The inductor 42 and the resonant capacitor 41 are connected in series with the primary side coil of the transformer 5, and the first resonant inductor 43 is connected to both ends of the primary side coil to make the first resonant inductor 42 The two-spectrum oscillator 43 forms a parallel configuration from the primary side coil; the transfer function of the above-mentioned resonant unit 4 is derived as follows:

The value of A is the ratio of the first resonant inductor (Lr) 42 to the second resonant inductor (Lm) 43. · (2-1) L - Lm This is the series equivalent inductance of the resonant unit 4 . . . (2-2) 200934075 0 Ws This is the resonant frequency, .,. (2_3) 1 Q 1 {cs * · · (2-4) D ^lamp ^iamp (2-5)

Z〇 ~ COL This is the impedance of the element of the face unit. Q = ^〇C, Rlamp = This is the series resonance quality factor.... (1+4

+J

Q

A_ 〇> „ l~A This is the transfer function of the resonance unit 4 ... (2_6 type)

This is the gain value of (2_6 type)... (2_7 type) When the converter wants to start the tube group 9, the tube group 9 has the same equivalent at the initial start and has a relatively equivalent a resistor (Rlamp), and no current flows in the spectroscopic unit 4 when the converter is not in operation, and the pulse width modulation unit 3 can generate a duty cycle signal of a preset starting frequency to make the resonating unit 4 is activated at the starting frequency, and thus has a starting voltage gain corresponding to the starting frequency. Therefore, the resonant unit 4 can have a higher voltage gain to smoothly start the tube group 9, and the tube group 9 will have a current after starting. Circulates on the secondary side of the transformer 5, so that the return Φ Φ 200934075 can be obtained by the unit 7 to be sent to the ship width varying unit 3 to make the red at the preset operating frequency, and the resonant unit 4 is based on the pulsed power. Corresponding to the working frequency: as shown in FIG. 4, when the lamp group 9 is activated, the resonating unit 4 operates at the starting voltage point P1, and the lamp group 9 works after being operated normally. The working frequency of the higher frequency (4) is the benefit point P2, therefore, the spectral unit 4 can When the lamp group 9 is started and during normal operation, the voltage increase is continued in the start leg tube group 9, and the field lamp is made to be 9 normal Wang Zuo milk "4 can provide corresponding power according to the frequency of the pulse power _ Benefits, to achieve the effect of controlling the brightness of the lamp ^ 9; and the implementation of the above-mentioned circuit paste vibrating unit * paved in Figure 5, where Pin is the power input to the converter, FS is the touch-sensitive table towel ^ 1 column six shots It is known that when the vibration unit 4 HH is lower, the higher lamp (Vl_) can be generated, and the higher lamp (4) pressure (=P) is beneficial to start the tube group 9, and the lamp group 9 is normally operated, etc. The effective resistance il drops 'fresh rises to a higher operating frequency, and the voltage 婵== rate of the resonant unit 4 becomes smaller and the lamp tube cage (ν~) decreases, and the figure can be confirmed by the value Fresh Element 4 Paste - Job Series 42, 2's = The circuit structure of the resonant capacitor 41 can change its output power = voltage by controlling the operating frequency to achieve the effect of adjusting the brightness of the tube group 9. , 'Electric j 郷 郷 杂 杂 杂 杂 杂 杂 郷 郷 郷 郷 43 43 43 43 43 43 43 « « « « « « « « « « « « « « « « « « « « « « « « « « « « « « « More movements and retouchings should be covered in the present invention: === Please apply for patents. As described in the application of the smuggling of the smuggling ship, the present invention is more customary than the legally-increased legal patent requirements for the circuit, and it is legally required to comply with the patent application of the novelty. Creation, to the sense of i will go to k Shen Shen, I ask you to approve this article issued 200934075 [Simple diagram of the diagram] Figure 1 is the converter structure diagram of the conventional drive lamp. 2-1 is a diagram of a conventional resonant unit architecture of the inverter of FIG. 1. Figure 2-2 shows the gain curve of the transfer function of Figure 2-1. 3 is a circuit diagram of the present invention. 4 is a graph showing the gain function of the conversion function of FIG. Figure 5 is a table of measured values of the circuit shown in Figure 3. [Main component symbol description] 1 .......Power source 2 .......Switch unit

3 ....... pulse width modulation unit 4 .... resonance unit 41 ... resonance capacitor 42 .... first resonance inductance 43 .... ...the second vibrational inductance 5 ....the transformer 6 .......the dimming signal source 7 .......the feedback unit 8 ....frequency control Unit 9 .......Lamp tube group P1.......Start voltage gain point P2.......Working voltage gain point 11

Claims (1)

200934075 X. Patent application scope: 1.-, variable hybrid slave inverter 'The converter includes - pulse width modulation unit, - switch soap 70, - resonance unit and - converter, the converter The device is connected to a power source to obtain the DC power, and the pulse width modulation unit generates a duty cycle signal to drive the switching switch unit to convert the DC power into a pulse power and the resonant unit converts the pulse power into a driving power The cage H is converted into a turn-over power to drive the lamp set connected to the prison, characterized in that: the pulse power is at a start frequency and an operating frequency higher than the start frequency, the resonance single 7G The corresponding start-up speech and the vocabulary of the __ start voltage gain and a working power I gain respectively are generated, and the start voltage gain is greater than the guard voltage to activate the lamp set. 2. The commutation of the variable spectral gain of the patent application is as follows: wherein the spectral unit has 3 " white oscillator inductance, a second resonant inductor and a resonant capacitor, wherein the first resonant inductor and The damper capacitor is connected in series with the primary side coil of the transformer, and the second oscillating inductance is connected to the two ends of the second side coil, so that the _ spectral inductance and the second impurity inductance are from the primary side line The view forms a parallel configuration. 3. The converter of the variable gain according to the second aspect of the invention, wherein the first resonant inductor and the second resonant inductor have different sensitivities. 4. The variable resonant gain converter of claim 2, wherein the ratio of the two sensed inductances of the spectral unit is less than 10:1. 5. The converter of claim 5, wherein the converter further comprises a feedback unit, a dimming signal source, and a frequency control unit, wherein the dimming signal source Generating a dimming signal. The feedback unit obtains a feedback signal from the secondary side of the transformer, and the frequency control unit determines a reference frequency signal for the pulse width modulation unit according to the dimming signal and the feedback signal. The frequency of the duty cycle signal. 12