CN111511079B - Strobe-free dimming driver utilizing input valley bottom compensation - Google Patents

Abstract

The present invention discloses a non-flicker dimming driver using input valley compensation, including a fuse module, a rectifier module, a dimming driver module, a valley compensation unit, a filter module, an input current waveform detection circuit, a power supply circuit, an electrolytic filter circuit and a ripple removal circuit. The input AC power supply is connected to the input end of the fuse module, the output end of the fuse module is connected to the rectifier module and the filter module in sequence, the output end of the filter module is connected to the input end of the input current waveform detection circuit, one end of the output end of the input current waveform detection circuit is connected to the input end of the power supply circuit, and the other end outputs a dimming signal to the dimming driver module, the output end of the power supply circuit is connected to the input end of the dimming driver module, the output end of the dimming driver module is connected to the electrolytic filter circuit and the ripple removal circuit in sequence, and the input end of the dimming driver module is also connected to the valley compensation unit. The present invention realizes non-flicker current output, reliable dimming compatibility and low price.

Description

A flicker-free dimming driver using input valley compensation

Technical Field

The invention relates to the technical field of DC power supply and LED driver, and in particular to a flicker-free dimming driver utilizing input valley compensation.

Background Art

LED has the advantages of high luminous efficiency, long service life and good stability, and is widely used in the field of lighting. When using LED lighting or LED backlight, it is often required to be able to adjust the brightness of the LED. However, although LED dimming technology continues to develop, its shortcomings in efficiency, reliability and compatibility have always hindered the service life and popularity of LED lighting systems.

LED thyristor dimming technology is developed by combining traditional thyristor dimmers with emerging LED drive technology, and is mainly used in the replacement LED lamp market. Thyristor dimmers were originally used to dim incandescent lamps and fluorescent lamps. In the process of promoting LED lighting, it is required that the infrastructure of the existing lighting system should not be changed. Therefore, if LED lamps can use thyristor dimmers for dimming, it can greatly reduce the threshold for entering the market and easily replace conventional lamps.

With the country's vigorous promotion of energy-saving products, the market demand for DC power supplies and LED drivers is increasing. Under various changes in demand, the functions and requirements of power supplies and LED drivers are getting higher and higher. In thyristor dimming applications, thyristor dimmers are generally based on 120V American standard, with a lower input voltage. Compared with the European standard of 220-240V, the input current of 120V American standard thyristor dimmers is more than doubled, which has obvious advantages for the maintenance current of thyristor dimmers.

The relative technical difficulty of the 220-240V European standard thyristor dimming on the high-voltage side is relatively large, especially in terms of input current subharmonics, which is difficult to meet the requirements of European certification standards. In addition, since the input voltage of the 220-240V European standard thyristor dimming on the high-voltage side is relatively high and the input current is relatively small, it is difficult to meet the thyristor dimmer's maintenance current requirements, and when the thyristor dimmer is adjusted to a smaller angle, the input current oscillation is prone to zero crossing, causing low-end flicker and other problems.

The common LED segmented constant current drive circuit structure requires the connection of a thyristor dimmer before the rectifier bridge to form a dimming application. Since the thyristor dimmer must have a certain holding current to remain on, the output current can only be generated normally when the input power frequency voltage VAC is greater than the output voltage Vout. Among them, the system has problems such as low driving efficiency and low power factor, and the system power will change with the input voltage. The power supply regulation rate is poor. Due to the influence of multipath and external factors, the test performance is not ideal, which also affects real-time communication.

The initial conduction angle and minimum conduction angle of various dimmers on the market vary greatly. For dimmers with a small initial conduction angle, the initial power at the maximum conduction angle of the dimmer will be much lower than when the dimmer is not connected; while for dimmers with a large minimum conduction angle, the residual power at the minimum conduction angle of the dimmer will be relatively large. On the other hand, when the dimmer is adjusted to the maximum voltage of the input power frequency voltage Vin and the output voltage Vout are close, a slight change in the conduction angle of the dimmer will cause a significant difference in the output current, causing the light to flicker.

Summary of the invention

The present invention aims to overcome the technical problems in the prior art that when a thyristor dimming driver is adjusted to a smaller angle, the input current oscillates and crosses zero easily, causing low-end flicker, and the maintenance current of the thyristor dimming driver is difficult to meet. The present invention provides a flicker-free dimming driver using input valley compensation, adopts a voltage phase cutting method to change the output voltage for adjustment, uses a single-stage thyristor dimming flyback power supply to add a flicker-free ripple removal control circuit and a valley compensation circuit, extracts the input voltage valley signal to control the valley compensation circuit, corrects the input current waveform at the valley of each large cycle, improves the input current waveform to be closer to a sine wave, improves the power factor PF, reduces the total harmonic THD, and the sub-harmonics meet the requirements of European certification standards, reduces the turn-on current peak value at the valley of the input current, reduces the peak oscillation amplitude, and directly raises the zero crossing point in the thyristor dimming state to a certain height, so as to achieve the purpose of preventing the input current oscillation from crossing zero during the thyristor adjustment process, solves the flicker problem under a small maintenance current, and achieves the purpose of current output without frequency flicker.

In order to achieve the above object, the present invention adopts the following technical solutions:

A flicker-free dimming driver using input valley compensation, the driver comprising a fuse module, a rectifier module, a dimming driver module, a valley compensation unit, a filter module, an input current waveform detection circuit, a power supply circuit, an electrolytic filter circuit and a ripple removal circuit, the input AC power supply is connected to the input end of the fuse module, the output end of the fuse module is connected to the rectifier module and the filter module in sequence, the output end of the filter module is connected to the input end of the input current waveform detection circuit, one end of the output end of the input current waveform detection circuit is connected to the input end of the power supply circuit, and the other end outputs a dimming signal to the dimming driver module, the output end of the power supply circuit is connected to the input end of the dimming driver module, the output end of the dimming driver module is connected to the electrolytic filter circuit and the ripple removal circuit in sequence, and the input end of the dimming driver module is also connected to the valley compensation unit.

The present invention utilizes a ripple removal circuit to achieve the purpose of frequency-free flickering current, and utilizes a valley compensation unit to perform input current waveform correction at the valley of each large cycle, so as to improve the input current waveform to be closer to a sine wave, thereby improving the power factor PF, reducing the total harmonic THD, and the sub-harmonics meet the requirements of European certification standards, reduce the turn-on current peak value at the valley of the input current, reduce the peak oscillation amplitude, and directly raise the zero-crossing point in the thyristor dimming state to a certain height, so as to achieve the input current oscillation without passing zero during the thyristor adjustment process, and solve the problem of flickering under a small maintaining current.

Preferably, the ripple removal circuit includes a flicker-free ripple removal chip US51, a resistor RS71A, a resistor RS71B, a resistor RS73A, a resistor RS73B, a resistor RS74A, a resistor RS74B, a resistor RS74C, a resistor RS74D, a resistor RS74E, a capacitor CS71, a capacitor CS72, a capacitor CS73, a capacitor CS74, a voltage regulator diode ZS71, a diode DS71, a MOS tube Q71 and an inductor L42. The VIN pin of the flicker-free ripple removal chip US51 passes through the capacitor CS 71 is connected to the ground, one path is connected to the electrolytic filter circuit through resistors RS71B and RS71A, and another path is connected to the cathode of the voltage stabilizing diode ZS71. The anode of the voltage stabilizing diode ZS71 is connected to the ground. The GND pin of the flicker-free ripple removal chip US51 is directly connected to the ground. The VC pin of the flicker-free ripple removal chip US51 is connected to the ground through capacitor CS72, and the other path is connected to the ground through resistor RS72. The VLMT pin of the flicker-free ripple removal chip US51 is connected to the ground through resistor RS71B and RS71A. 3B is connected to the ground terminal, and the other one is connected to one end of the resistor RS73A. The other end of the resistor RS73A is connected to both the positive electrode of the diode DS71 and the same-name end of the secondary winding of the inductor L42. The negative electrode of the diode DS71 is connected to the electrolytic filter circuit on one side, and the other one is connected to the same-name end of the primary winding of the inductor L42. The opposite-name end of the primary winding of the inductor L42 is connected to the X41A port, and the opposite-name end of the secondary winding of the inductor L42 is connected to the X41A port. The same-name end of the secondary winding of the inductor L42 is also connected to the MOS tube Q7 1, the gate of the MOS tube Q71 is connected to the VG pin of the flicker-free ripple removal chip US51, the VG pin of the flicker-free ripple removal chip US51 is connected to the ground through the capacitor CS74, and a parallel circuit of resistors RS74A, RS74B, RS74C, RS74D and RS74E is connected between the source of the MOS tube Q71 and the ground, and one end of the resistor RS74A and one end of the resistor RS74B are connected as an input end and connected to the VS pin of the flicker-free ripple removal chip US51. The flicker-free ripple removal chip US51 adopts the JW12510 model chip, and detects the low ripple DC signal through the VIN pin, compares the AC ripple with the set reference voltage, and outputs the MOS tube Q71 to follow the amplification working state to output constant current to achieve the ripple removal effect, thereby reducing the low ripple to the flicker-free state.

Preferably, the valley compensation unit includes a valley compensation circuit and an input voltage waveform detection circuit, the valley compensation circuit includes resistor RS54, resistor RS55, resistor RS56, capacitor CS53 and transistor QS53, the input voltage waveform detection circuit includes resistor RS53A, resistor RS53B and resistor RS53C, one end of the resistor RS53A is connected to the VDCBUS end, that is, connected to the rectifier module, the other end of the resistor RS53A is connected to one end of the resistor RS53B, and the other end of the resistor RS53B is connected to One path is connected to the base of the transistor QS53 after passing through the resistor RS54, one path is connected to the ground after passing through the resistor RS53B, and another path is connected to the cathode of the voltage-stabilizing diode ZS53. The anode of the voltage-stabilizing diode ZS53 is connected to the ground, the emitter of the transistor QS53 is connected to the ground, the collector of the transistor QS53 is connected to the power supply VCC terminal after passing through the resistor RS55, one path is connected to the IS terminal after passing through the resistor RS56, and another path is connected to one end of the capacitor CS53, and the other end of the capacitor CS53 is connected to the ground. The input voltage waveform detection circuit extracts the voltage signal of the input voltage valley <3V to control the on and off of the transistor ZS53 in the valley compensation circuit. When the valley voltage is <3V, the transistor is not turned on, and VCC injects a certain current into the peak detection pin of the chip US31 through the valley compensation circuit, so that the duty cycle of the driving main MOS tube Q41 is reduced by about 150us when the US31 chip is in the valley. The current in the middle of the valley becomes flat, making the entire input current waveform closer to a sine wave, thereby effectively improving the input power factor PF, reducing the total harmonic THD and sub-harmonics of the input current, and meeting the requirements of European certification standards.

Preferably, the dimming drive module includes a thyristor dimmer and its peripheral circuit, the thyristor dimmer includes a single-stage thyristor dimming constant current chip US31, the peripheral circuit includes resistors RS35A, RS35B, RS35C, RS34A, RS34B, RS34C, RS32B, RS32A, RS32C, RS32D, RS32E, diode DS31, MOS tube Q41, capacitor C43, capacitor CS61, capacitor CS34, capacitor C61, inductor L43, inductor L44 and inductor L41C, the single-stage thyristor dimming constant current chip The VCC pin of chip US31 is connected to the power supply VCC end, one end of capacitor CS61, one end of capacitor C61, and one end of power supply circuit. The other end of capacitor CS61 is connected to the GND pin of single-stage thyristor dimming constant current chip US31. The GND pin of single-stage thyristor dimming constant current chip US31 is connected to the negative electrode of capacitor C61. The negative electrode of capacitor C61 is connected to the ground. The Output pin of single-stage thyristor dimming constant current chip US31 is connected to one end of resistor RS35A through resistor RS35B. The other end of resistor RS35A is connected to The negative electrode of the diode DS31 is connected to one end of the resistor RS35A, the positive electrode of the diode DS31 is connected to the other end of the resistor RS35A, the drain of the MOS tube Q41 is connected to one end of the inductor L44, and a parallel circuit of resistors RS32A, RS32B, RS32C, RS32D and RS32E is connected between the source of the MOS tube Q41 and both ends of the ground terminal. The Isence foot of the single-stage thyristor dimming constant current chip US31 is connected to one end of the resistor RS32E through the capacitor CS34, and the other end is connected to the resistor RS34 A is connected to one end of the resistor RS34A, one end of the resistor RS34A is connected to the ground through the resistor RS34C and the switch K1, one end is connected to the IS end, that is, connected to the valley compensation unit, and the other end is connected to the source of the MOS tube Q41 through the resistor RS34B. The other end of the resistor RS32E is connected to the drain of the MOS tube Q41 through the capacitor C43. The VIN foot of the single-stage thyristor dimming constant current chip US31 is connected to the input current waveform detection circuit, and the other end of the inductor L44 is connected to the opposite end of the primary winding of the inductor L41C through the inductor L43. The same end of the primary winding of the inductor L41C is connected to the power supply circuit. The single-stage thyristor dimming constant current chip US31 adopts the IW3605 model. In order to achieve dimming power stability, the internal control drive output is set to the input current valley, and the duty cycle of the drive opening time is increased to about 85%, and is about 300 microseconds at the valley.

Preferably, the electrolytic filter circuit includes a rectifier diode D43A, a rectifier diode D43B, a rectifier diode D43C, a capacitor C43A, a capacitor C43B, a capacitor C43C and a capacitor C31A. The opposite ends of the secondary winding of the inductor L41C in the dimming drive module are connected to the positive electrode of the diode D43A, one end is connected to the positive electrode of the diode D43B, and another end is connected to the positive electrode of the diode D43C. The same end of the secondary winding of the inductor L41, the negative electrode of the capacitor C43A, the negative electrode of the capacitor C43B, the negative electrode of the capacitor C43C and the negative electrode of the capacitor C43D are connected, and connected to the ground after passing through the capacitor C31A. After the positive electrode of tube D43B is connected to the positive electrode of diode D43C, one path is connected to the positive electrode of capacitor C43A, one path is connected to the positive electrode of capacitor C43C, one path is connected to the positive electrode of capacitor C43C, and another path is connected to one end of resistor RS71A of the ripple removal circuit. After the positive electrode of capacitor C43A and the positive electrode of capacitor C43B are connected, they are connected to the positive electrode of diode D43A. The positive electrode of capacitor C43C is also connected to the positive electrode of capacitor C43D, and the negative electrode of capacitor C43C is also connected to the negative electrode of capacitor C43D.

Preferably, the rectifier module includes a rectifier circuit, which is composed of four diodes DS11, a diode DS12, a diode DS13 and a diode DS14. The positive electrode of the diode DS13 and the positive electrode of the diode DS14 are connected to the ground, and the negative electrode of the diode DS11 and the negative electrode of the diode DS12 are connected as the output end, one path is connected to one end of the resistor RS53A of the input voltage waveform detection circuit, and the other path is connected to the same end of the inductor L41A of the dimming drive module, and the positive electrode of the DS11 is connected to the negative electrode of the DS14 and is connected to the insurance module as an input end.

Preferably, the filtering module includes a resistor RS21, a resistor RS23, a capacitor C21, a capacitor C22, a capacitor C23, a diode DS21, an inductor L21 and a thermistor VD21, one end of the inductor L21 is connected to one end of the resistor R23 through the capacitor C22, one end of the resistor R23 is also connected to the cathode of the diode DS21, the other end of the resistor R23 is connected to the anode of the diode DS21 in one way, and to the anode of the diode DS14 of the rectifier module in the other way, a capacitor C21 is connected in parallel between the cathode of the diode DS12 of the rectifier module and the anode of the diode DS14, the other end of the inductor L21 is connected to one end of the capacitor C23, the other end of the capacitor C23 is connected to the ground, the two ends of the capacitor C23 are connected in parallel with the thermistor VD21, and the two ends of the inductor L21 are connected in parallel with the resistor RS21.

Preferably, the insurance module comprises a capacitor C11, a insurance resistor R11, an EMI common mode inductor L11, an EMI common mode inductor L12 and a thermistor D11, the opposite end of the primary winding of the EMI common mode inductor L11 is connected to the X11A interface of the input AC power supply, one end of the insurance resistor R11 is connected to the X11B interface of the input AC power supply, the other end of the insurance resistor R11 is connected to the opposite end of the secondary winding of the EMI common mode inductor L11, the same end of the primary winding of the EMI common mode inductor L11 is connected to the opposite end of the primary winding of the EMI common mode inductor L12, and the The like-name end of the secondary winding of the EMI common-mode inductor L11 is connected to the unlike-name end of the secondary winding of the EMI common-mode inductor L12, one end of the thermistor D11 is connected to the like-name end of the primary winding of the EMI common-mode inductor L11, the other end of the thermistor D11 is connected to the like-name end of the secondary winding of the EMI common-mode inductor L11, a capacitor C11 is connected between the like-name end of the primary winding of the EMI common-mode inductor L12 and the like-name end of the secondary winding of the EMI common-mode inductor L12, one end of the capacitor C11 is connected to the positive electrode of the diode DS11 of the rectifier module, and the other end is connected to the negative electrode of the diode DS14.

Preferably, the input current waveform detection circuit includes resistors RS31A, RS31B, RS31C and capacitor CS31, the power supply circuit includes resistors RS62A, RS62B and MOS tube QS62, the drain of the MOS tube QS62 is connected to one end of the resistor RS62A through the resistor RS62B, the other end of the resistor RS62A is connected to the same end of the primary winding of the inductor L41C, and the other end is connected to one end of the inductor L21 in the filter module, the source of the MOS tube QS62 is connected to the VCC pin of the single-stage thyristor dimming constant current chip US31, one end of the resistor RS31A is connected to the VDCBUS end, the other end of the resistor RS31A is connected to one end of the resistor RS31C through the resistor RS31B, the other end of the resistor RS31C is connected to the gate of the MOS tube QS62, and the other end is connected to one end of the capacitor CS33 through the capacitor CS31. The power supply circuit provides the driver with an initial power supply VCC.

The beneficial effects of the present invention are: 1. A ripple removal circuit is used to achieve the purpose of flash-free current output, with reliable dimming compatibility and low price; 2. A valley compensation circuit is used to reduce the turn-on current peak value when the input current is at the valley bottom, reduce the peak oscillation amplitude, and directly raise the zero-crossing point in the thyristor dimming state to a certain height, so as to achieve the input current oscillation without crossing zero during the thyristor adjustment process, and solve the problem of flicker under a small holding current; 3. An input voltage waveform detection circuit is used to extract the input voltage valley signal to control the valley compensation circuit, and perform input current waveform correction at the valley bottom of each large cycle to improve the input current waveform to be closer to a sine wave, thereby improving the power factor PF, reducing the total harmonic THD, and the sub-harmonics meet the requirements of European certification standards.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a circuit principle connection structure block diagram of the present invention.

FIG. 2 is a circuit principle connection diagram of the present invention.

FIG. 3 is another circuit principle connection structure block diagram of the present invention.

FIG. 4 is another circuit principle connection diagram of the present invention.

In the figure, 1. insurance module, 2. rectifier module, 3. dimming drive module, 301. thyristor dimmer, 4. valley compensation unit, 401. input voltage waveform detection circuit, 5. filter module, 6. input current waveform detection circuit, 7. power supply circuit, 8. electrolytic filter circuit, 9. ripple removal circuit.

DETAILED DESCRIPTION

The technical solution of the present invention is further specifically described below through embodiments and in conjunction with the accompanying drawings.

Embodiment 1: A flicker-free dimming driver using input valley compensation in embodiment 1 is shown in Figure 1. The driver includes a fuse module 1, a rectifier module 2, a dimming driver module 3, a valley compensation unit 4, a filter module 5, an input current waveform detection circuit 6, a power supply circuit 7, an electrolytic filter circuit 8 and a ripple removal circuit 9. The input AC power supply is connected to the input end of the fuse module 1, and the output end of the fuse module 1 is connected to the rectifier module 2 and the filter module 5 in sequence. The output end of the filter module 5 is connected to the input end of the input current waveform detection circuit 6. One end of the output end of the input current waveform detection circuit 6 is connected to the input end of the power supply circuit 7, and the other end outputs a dimming signal to the dimming driver module 3. The output end of the power supply circuit 7 is connected to the input end of the dimming driver module 3. The output end of the dimming driver module 3 is connected to the electrolytic filter circuit 8 and the ripple removal circuit 9 in sequence. The input end of the dimming driver module 3 is also connected to the valley compensation unit 4.

As shown in FIG2 , the ripple removal circuit 9 includes a flicker-free ripple removal chip US51, a resistor RS71A, a resistor RS71B, a resistor RS73A, a resistor RS73B, a resistor RS74A, a resistor RS74B, a resistor RS74C, a resistor RS74D, a resistor RS74E, a capacitor CS71, a capacitor CS72, a capacitor CS73, a capacitor CS74, a voltage regulator diode ZS71, a diode DS71, a MOS tube Q71 and an inductor L42. The VIN pin of the flicker-free ripple removal chip US51 is connected to the VIN pin through the inductor L42. The first circuit is connected to the ground after capacitor CS71, and the second circuit is connected to the electrolytic filter circuit 8 after passing through resistors RS71B and RS71A. The third circuit is connected to the cathode of the voltage stabilizing diode ZS71. The anode of the voltage stabilizing diode ZS71 is connected to the ground. The GND pin of the flicker-free ripple removal chip US51 is directly connected to the ground. The VC pin of the flicker-free ripple removal chip US51 is connected to the ground after passing through capacitor CS72, and the other circuit is connected to the ground after passing through resistor RS72. The VLMT pin of the flicker-free ripple removal chip US51 is connected to the ground after passing through resistor RS73B is connected to the ground terminal, and the other end is connected to one end of the resistor RS73A. The other end of the resistor RS73A is connected to both the positive electrode of the diode DS71 and the same-name end of the secondary winding of the inductor L42. The negative electrode of the diode DS71 is connected to the electrolytic filter circuit 8 on one path, and the other end is connected to the same-name end of the primary winding of the inductor L42. The opposite-name end of the primary winding of the inductor L42 is connected to the X41A port, and the opposite-name end of the secondary winding of the inductor L42 is connected to the X41A port. The same-name end of the secondary winding of the inductor L42 is also connected to the MOS tube The drain of Q71 is connected, the gate of the MOS tube Q71 is connected to the VG pin of the flicker-free ripple removal chip US51, the VG pin of the flicker-free ripple removal chip US51 is connected to the ground through the capacitor CS74, and a parallel circuit of resistors RS74A, RS74B, RS74C, RS74D and RS74E is connected between the source of the MOS tube Q71 and the ground, one end of the resistor RS74A and one end of the resistor RS74B are connected as an input end and connected to the VS pin of the flicker-free ripple removal chip US51.

The valley compensation unit 4 includes a valley compensation circuit and an input voltage waveform detection circuit 401. The valley compensation circuit includes a resistor RS54, a resistor RS55, a resistor RS56, a capacitor CS53 and a transistor QS53. The input voltage waveform detection circuit 401 includes a resistor RS53A, a resistor RS53B and a resistor RS53C. One end of the resistor RS53A is connected to the VDCBUS end, that is, connected to the rectifier module 2. The other end of the resistor RS53A is connected to one end of the resistor RS53B. The other end of the resistor RS53B is connected to One path is connected to the base of the transistor QS53 after passing through resistor RS54, one path is connected to the ground after passing through resistor RS53B, and another path is connected to the cathode of the Zener diode ZS53. The anode of the Zener diode ZS53 is connected to the ground, the emitter of the transistor QS53 is connected to the ground, the collector of the transistor QS53 is connected to the power supply VCC terminal after passing through resistor RS55, one path is connected to the IS terminal after passing through resistor RS56, and another path is connected to one end of the capacitor CS53, and the other end of the capacitor CS53 is connected to the ground.

The dimming drive module 3 includes a thyristor dimmer 301 and its peripheral circuits. The thyristor dimmer 301 includes a single-stage thyristor dimming constant current chip US31. The peripheral circuit includes resistors RS35A, RS35B, RS35C, RS34A, RS34B, RS34C, RS32B, RS32A, RS32C, RS32D, RS32E, diode DS31, MOS tube Q41, capacitor C43, capacitor CS61, capacitor CS34, capacitor C61, inductor L43, inductor L44 and inductor L41C. The single-stage thyristor dimming constant current The VCC pin of chip US31 is connected to the power supply VCC terminal, one end of capacitor CS61, one end of capacitor C61, and one end of power supply circuit 7. The other end of capacitor CS61 is connected to the GND pin of single-stage thyristor dimming constant current chip US31. The GND pin of single-stage thyristor dimming constant current chip US31 is connected to the negative electrode of capacitor C61. The negative electrode of capacitor C61 is connected to the ground terminal. The Output pin of single-stage thyristor dimming constant current chip US31 is connected to one end of resistor RS35A through resistor RS35B. The other end of resistor RS35A is connected to The ground terminal is connected to the ground terminal, and the other is connected to the gate of the MOS tube Q41. The cathode of the diode DS31 is connected to one end of the resistor RS35A, the anode of the diode DS31 is connected to the other end of the resistor RS35A, the drain of the MOS tube Q41 is connected to one end of the inductor L44, and a parallel circuit of resistors RS32A, RS32B, RS32C, RS32D and RS32E is connected between the source of the MOS tube Q41 and both ends of the ground terminal. The Isence foot of the single-stage thyristor dimming constant current chip US31 is connected to one end of the resistor RS32E through the capacitor CS34, and the other is connected to the resistor RS34 A is connected to one end of the resistor RS34A, one end of the resistor RS34A is connected to the ground through the resistor RS34C and the switch K1, one end is connected to the IS end, that is, it is connected to the valley compensation unit 4, and the other end is connected to the source of the MOS tube Q41 through the resistor RS34B. The other end of the resistor RS32E is connected to the drain of the MOS tube Q41 through the capacitor C43. The VIN pin of the single-stage thyristor dimming constant current chip US31 is connected to the input current waveform detection circuit 6. The other end of the inductor L44 is connected to the opposite end of the primary winding of the inductor L41C through the inductor L43, and the same end of the primary winding of the inductor L41C is connected to the power supply circuit 7.

The electrolytic filter circuit 8 includes a rectifier diode D43A, a rectifier diode D43B, a rectifier diode D43C, a capacitor C43A, a capacitor C43B, a capacitor C43C and a capacitor C31A. The opposite-name ends of the secondary winding of the inductor L41C in the dimming drive module 3 are connected to the positive electrode of the diode D43A, one is connected to the positive electrode of the diode D43B, and another is connected to the positive electrode of the diode D43C. The same-name end of the secondary winding of the inductor L41, the negative electrode of the capacitor C43A, the negative electrode of the capacitor C43B, the negative electrode of the capacitor C43C and the negative electrode of the capacitor C43D are connected, and connected to the ground through the capacitor C31A. The diode After the positive electrode of D43B is connected to the positive electrode of diode D43C, one path is connected to the positive electrode of capacitor C43A, one path is connected to the positive electrode of capacitor C43C, one path is connected to the positive electrode of capacitor C43C, and another path is connected to one end of resistor RS71A of de-ripple circuit 9. After the positive electrode of capacitor C43A and the positive electrode of capacitor C43B are connected, they are connected to the positive electrode of diode D43A. The positive electrode of capacitor C43C is also connected to the positive electrode of capacitor C43D, and the negative electrode of capacitor C43C is also connected to the negative electrode of capacitor C43D.

The rectifier module 2 includes a rectifier circuit, which consists of four diodes DS11, a diode DS12, a diode DS13 and a diode DS14. The positive electrode of the diode DS13 and the positive electrode of the diode DS14 are connected to the ground terminal, and the negative electrode of the diode DS11 and the negative electrode of the diode DS12 are connected as output terminals. One path is connected to one end of the resistor RS53A of the input voltage waveform detection circuit 401, and the other path is connected to the same-name end of the inductor L41A of the dimming drive module 3. The positive electrode of DS11 is connected to the negative electrode of DS14 and is connected to the insurance module 1 as an input terminal.

The filtering module 5 includes a resistor RS21, a resistor RS23, a capacitor C21, a capacitor C22, a capacitor C23, a diode DS21, an inductor L21 and a thermistor VD21. One end of the inductor L21 is connected to one end of the resistor R23 through the capacitor C22, and one end of the resistor R23 is also connected to the cathode of the diode DS21. The other end of the resistor R23 is connected to the anode of the diode DS21 in one way and to the anode of the diode DS14 of the rectifier module 2 in the other way. The capacitor C21 is connected in parallel between the cathode of the diode DS12 of the rectifier module 2 and the anode of the diode DS14. The other end of the inductor L21 is connected to one end of the capacitor C23, and the other end of the capacitor C23 is connected to the ground. The two ends of the capacitor C23 are connected in parallel with the thermistor VD21, and the two ends of the inductor L21 are connected in parallel with the resistor RS21.

The insurance module 1 includes a capacitor C11, a insurance resistor R11, an EMI common mode inductor L11, an EMI common mode inductor L12 and a thermistor D11. The opposite-name end of the primary winding of the EMI common mode inductor L11 is connected to the X11A interface of the input AC power supply, one end of the insurance resistor R11 is connected to the X11B interface of the input AC power supply, the other end of the insurance resistor R11 is connected to the opposite-name end of the secondary winding of the EMI common mode inductor L11, the same-name end of the primary winding of the EMI common mode inductor L11 is connected to the opposite-name end of the primary winding of the EMI common mode inductor L12, and the EMI common mode inductor The like-name end of the secondary winding of the inductor L11 is connected to the unlike-name end of the secondary winding of the EMI common-mode inductor L12, one end of the thermistor D11 is connected to the like-name end of the primary winding of the EMI common-mode inductor L11, the other end of the thermistor D11 is connected to the like-name end of the secondary winding of the EMI common-mode inductor L11, a capacitor C11 is connected between the like-name end of the primary winding of the EMI common-mode inductor L12 and the like-name end of the secondary winding of the EMI common-mode inductor L12, one end of the capacitor C11 is connected to the positive electrode of the diode DS11 of the rectifier module, and the other end is connected to the negative electrode of the diode DS14.

The input current waveform detection circuit 6 includes a resistor RS31A, a resistor RS31B, a resistor RS31C and a capacitor CS31, and the power supply circuit 7 includes a resistor RS62A, a resistor RS62B and a MOS tube QS62. The drain of the MOS tube QS62 is connected to one end of the resistor RS62A through the resistor RS62B, the other end of the resistor RS62A is connected to the same end of the primary winding of the inductor L41C in one way, and is connected to one end of the inductor L21 in the filter module 5 in another way. The source of the MOS tube QS62 is connected to the VCC pin of the single-stage thyristor dimming constant current chip US31, one end of the resistor RS31A is connected to the VDCBUS end, the other end of the resistor RS31A is connected to one end of the resistor RS31C through the resistor RS31B, the other end of the resistor RS31C is connected to the gate of the MOS tube QS62 in one way, and is connected to one end of the capacitor CS33 in another way after passing through the capacitor CS31.

The working process of this embodiment is as follows: the input AC power first passes through the insurance resistor R11, EMI common mode inductor L11 and EMI common mode inductor L12 of the insurance module 1, and then is rectified by the rectifier diodes DS11, rectifier diodes DS12, rectifier diodes DS13 and rectifier diodes DS14 of the rectifier module 2 and filtered by the capacitors C21 and C23 in the filter module 5. The input current waveform detection circuit composed of the resistor RS31A, the resistor RS31B, the resistor RS31C and the capacitor CS31 provides the input current waveform to the VIN pin of the single-stage thyristor dimming constant current chip US31, and drives the power supply circuit composed of the resistor RS62A, the resistor RS62B and the MOS tube QS62 to provide the initial VCC to the dimming drive module 3.

When the initial VCC of the capacitor C61 reaches 14V, the single-stage thyristor dimming constant current chip US31 starts to work, and the output of the resistor RS35B and the resistor RS35A drives the MOS tube Q41 to turn on. When the MOS tube Q41 is turned on, the MOS tube Q41 stores energy in the flyback inductor L43. When the MOS tube Q41 is turned off, the energy of the inductor L43 is output to the electrolytic filter circuit 8 and rectified by the rectifier diode D43. After the electrolytic filtering by the capacitor C43, a low ripple DC voltage is obtained and superimposed on both ends of the ripple removal circuit.

When the resistors RS71A and RS71B of the ripple removal circuit charge the capacitor CS71 to 9V VDD, the flicker-free ripple removal chip US51 of the ripple removal circuit, i.e., the chip JW12510, starts to work. The chip first provides a low-ripple DC signal to the VIN pin on the chip JW12510 through the resistors RS71A and RS71B for detection, and the AC ripple is compared with the reference voltage set by the capacitor CS72 connected to the VC pin of the chip JW12510, so as to output the drive MOS tube Q71 to follow, so that the driver enters the amplification working state for constant current output, so as to achieve the ripple removal effect and reduce the low ripple to the flicker-free state.

When the input current waveform detection circuit provides an input voltage waveform to the VIN pin of the chip IW3605, and the chip IW3605 recognizes that it is at the bottom of the valley, the chip IW3605 drives the main MOS tube Q41 through the resistors RS35A and RS35B. During this period, the duty cycle of the drive signal is increased to about 85%, and the duration at the bottom of the valley is about 300us. This causes the chip to pull too much current when the input current waveform is at the bottom of the valley, and the bottom of the input current waveform is not smooth, causing the total harmonic THD and the sub-harmonics to completely fail to meet the requirements of the European certification standards.

In order to solve this problem, an input voltage waveform detection circuit composed of resistors RS53A, RS53B and RS53C is used to extract the voltage signal when the input voltage is at the bottom of the valley <3V, and control the transistor QS53 in the valley compensation circuit through resistor RS54. When the input voltage is at the bottom of the valley <3V, transistor QS53 is cut off, and the power supply VCC end injects a certain current into the peak detection pin Isense pin of the chip IW3605 through resistors RS55 and RS56 in the valley compensation circuit, so that the chip IW3605 reduces the amplitude of the drive signal at the bottom of the valley, and reduces the duty cycle of the drive signal to <60% for about 150us, so that the entire input current waveform becomes flat at the bottom of the valley, making the entire input current waveform closer to a sine wave. Effectively improve the input power factor PF, reduce the total harmonic THD and sub-harmonics of the input current, and meet the requirements of European certification standards.

When the thyristor dimmer is connected, the input current waveform detection circuit composed of resistors RS31A, RS31B, RS31C and capacitor CS31 provides a dimming signal to the VIN pin inside the chip IW3605, and the chip IW3605 identifies and determines which dimming working state the thyristor dimmer is in. At this time, the active discharge SNB pin on the chip IW3605 works, and the excess current after the dimmer phase is cut is released through resistors RS62A, RS62B and MOS tube QS62.

The input current waveform becomes distorted after the dimmer switches phase, mainly because there is no input current in the period after the dimmer switches phase, while all required output current is provided during the operation of the dimmer, resulting in a large charging peak current at the moment the dimmer works, which oscillates with the inductance and capacitance inside the driver, causing the input current to oscillate through zero. In order to reduce the instantaneous charging peak current of the dimmer, the resistors RS53A, RS53B and RS53C are used to input the voltage waveform to detect the dimmer, and the compensation time is controlled by the resistor RS54 and the transistor QS53, while the resistors RS55, RS56 and the filter capacitor CS53 provide the compensation size, and then the resistors RS34A and RS34B inject a certain current into the peak detection pin Isense of the chip IW3605, so that the driving duty cycle during the chip opening period is reduced from >85% to about <60%, so that the instantaneous peak value of the dimmer charging is reduced by about 1/3, and the output energy needs to be maintained after opening, so the input current oscillation peak-to-peak amplitude becomes narrower, so that the lower limit mean value of the current oscillation during the entire dimming period is raised above the zero potential, and the oscillation does not exceed zero, thereby maintaining a stable thyristor working process. Solve the problem of flicker under small holding current.

Embodiment 2: Embodiment 2 is a flicker-free dimming driver utilizing input valley compensation, as shown in FIG3 , the driver includes a fuse module 1, a rectifier module 2, a dimming driver module 3 and a valley compensation unit 4, the input AC power supply is connected to the input end of the fuse module 1, the output end of the fuse module 1 is connected to the input end of the rectifier module 2, the output end of the rectifier module 2 is connected to one end of the input end of the dimming driver module 3, the other end of the input end of the dimming driver module 3 is connected to the dimming signal, and the output end of the dimming driver module 3 is connected to the valley compensation unit 4.

As shown in FIG4 , the dimming driving module 3 includes a thyristor dimmer 301 and its peripheral circuits, wherein the peripheral circuits include a capacitor CS61, a resistor RS35A, a resistor RS35B, a resistor RS35C, a resistor RS32A, a resistor RS32C, a resistor RS32D, a resistor RS32E, a diode DS31, a MOS tube Q41 and an inductor L41A, wherein the drain of the MOS tube Q41 is connected to the same-name end of the inductor L41A, the gate of the MOS tube Q41 is connected to the positive electrode of the diode DS31 through the resistor RS35A, and the gate of the MOS tube Q41 is connected to the positive electrode of the diode DS31 through the resistor RS35C. C is directly connected to the ground, and the other path is connected to the thyristor dimmer after passing through resistors RS35A and RS35B. The cathode of the diode DS31 is connected to one end of the resistor 35A. The source of the MOS tube Q41 is connected in parallel with the resistors RS32A, RS32C, RS32D and RS32E between the two ends of the ground respectively. The source of the MOS tube Q41 is connected to the valley compensation unit 4. The drain of the MOS tube Q41 is connected to the opposite end of the inductor L41A, and the same end of the inductor L41A is connected to the valley compensation unit 4.

The thyristor dimmer 301 includes a single-stage thyristor dimming constant current chip US31, wherein one VCC pin of the single-stage thyristor dimming constant current chip US31 is connected to the power supply VCC end, and the other pin is connected to one end of the capacitor CS61, and the other end of the capacitor CS61 is connected to both the GND pin of the single-stage thyristor dimming constant current chip US31 and the valley compensation unit 4, the Output pin of the single-stage thyristor dimming constant current chip US31 is connected to one end of the resistor RS35B, the Isense pin of the single-stage thyristor dimming constant current chip US31 is connected to the valley compensation unit 4, and the VIN pin of the single-stage thyristor dimming constant current chip US31 is connected to the dimming signal.

The valley compensation unit 4 includes a valley compensation circuit, which includes a voltage stabilizing diode ZS53, a resistor RS54, a resistor RS55, a transistor QS53 and a capacitor CS53. The positive electrode of the voltage stabilizing diode ZS53 is connected to the other end of the capacitor CS61 of the dimming driving module 3, one end of the resistor RS53C of the input voltage waveform detection circuit, one end of the ground terminal, and one end of the capacitor CS53. The negative electrode of the voltage stabilizing diode ZS53 is connected to the other end of the resistor RS53C, and the other end is connected to the base of the transistor QS53 through the resistor RS54. The emitter of the transistor QS53 is directly grounded, and the collector of the transistor QS53 is connected to the power supply VCC terminal through the resistor RS55. The collector and emitter of the transistor QS53 are connected in parallel with the capacitor CS53.

The valley compensation circuit also includes resistor RS56, resistor RS34A, resistor RS34B, resistor RS32B and capacitor CS34. One end of resistor RS56 is connected to the collector of transistor QS53, and the other end is connected to one end of resistor RS34A and one end of resistor RS34B. The other end of resistor RS34B is connected to the other end of resistor RS34A after passing through resistor RS32B and capacitor CS34. Both ends of resistor RS32B are connected in parallel with resistor RS32A. The other end of resistor RS34A is connected to the Isense foot of single-stage thyristor dimming constant current chip US31.

The valley compensation unit 4 also includes an input voltage waveform detection circuit, which includes resistors RS53A, RS53B and RS53C. One end of the resistor RS53A is connected to the rectifier module 2, and the other end is connected to the same end of the inductor L41A. The other end of the resistor RS53A is connected to one end of the resistor RS53C through the resistor RS53B, and the other end of the resistor RS53C is connected to the positive electrode of the voltage-stabilizing diode ZS53.

The rectifier module 2 includes a rectifier circuit, which consists of four diodes DS11, a diode DS12, a diode DS13 and a diode DS14. The positive electrode of the diode DS13 and the positive electrode of the diode DS14 are connected to the ground terminal, and the negative electrode of the diode DS11 and the negative electrode of the diode DS12 are connected as the output terminal. One path is connected to one end of the resistor RS53A of the input voltage waveform detection circuit, and the other path is connected to the same end of the inductor L41A of the dimming drive module 3. The positive electrode of DS11 is connected to the negative electrode of DS14 and is connected to the insurance module 1 as an input terminal.

The insurance module 1 includes a capacitor C11, a insurance resistor R11, an EMI common mode inductor L11, an EMI common mode inductor L12 and a thermistor D11. The opposite-name end of the primary winding of the EMI common mode inductor L11 is connected to the X11A interface of the input AC power supply, one end of the insurance resistor R11 is connected to the X11B interface of the input AC power supply, the other end of the insurance resistor R11 is connected to the opposite-name end of the secondary winding of the EMI common mode inductor L11, the same-name end of the primary winding of the EMI common mode inductor L11 is connected to the opposite-name end of the primary winding of the EMI common mode inductor L12, and the EMI common mode inductor The like-name end of the secondary winding of the inductor L11 is connected to the unlike-name end of the secondary winding of the EMI common-mode inductor L12, one end of the thermistor D11 is connected to the like-name end of the primary winding of the EMI common-mode inductor L11, the other end of the thermistor D11 is connected to the like-name end of the secondary winding of the EMI common-mode inductor L11, a capacitor C11 is connected between the like-name end of the primary winding of the EMI common-mode inductor L12 and the like-name end of the secondary winding of the EMI common-mode inductor L12, one end of the capacitor C11 is connected to the positive electrode of the diode DS11 of the rectifier module, and the other end is connected to the negative electrode of the diode DS14.

The working process of this embodiment is as follows: the input AC power first passes through the insurance resistor R11, EMI common mode inductor L11 and EMI common mode inductor L12 of the insurance module 1, and then is rectified by the rectifier diodes DS11, rectifier diodes DS12, rectifier diodes DS13 and rectifier diodes DS14 of the rectifier module 2. When the initial VCC of the capacitor CS61 reaches 14V, the single-stage thyristor dimming constant current chip US31, that is, the chip IW3605 starts to work, and the output of the resistor RS35B and the resistor RS35A drives the MOS tube Q41 to turn on. When the MOS tube Q41 is turned on, the MOS tube Q41 stores energy for the flyback inductor L41A, and the duty cycle of the drive signal is increased to about 85%, and the duration is about 300us at the bottom of the valley. This causes the input current waveform to be pulled too much by the chip at the bottom of the valley, and the input current waveform is not smooth at the bottom of the valley, resulting in the total harmonic THD and the sub-harmonics completely failing to meet the requirements of the European certification standards.

In order to solve this problem, an input voltage waveform detection circuit composed of resistors RS53A, RS53B and RS53C is used to extract the voltage signal when the input voltage is at the bottom of the valley <3V, and control the transistor QS53 in the valley compensation circuit through resistor RS54. When the input voltage is at the bottom of the valley <3V, transistor QS53 is cut off, and the power supply VCC end injects a certain current into the peak detection pin Isense pin of the chip IW3605 through resistors RS55 and RS56 in the valley compensation circuit, so that the chip IW3605 reduces the amplitude of the drive signal at the bottom of the valley, and reduces the duty cycle of the drive signal to <60% for about 150us, so that the entire input current waveform becomes flat at the bottom of the valley, making the entire input current waveform closer to a sine wave. Effectively improve the input power factor PF, reduce the total harmonic THD and sub-harmonics of the input current, and meet the requirements of European certification standards.

The input current waveform becomes distorted after the dimmer switches phase, mainly because there is no input current in the period after the dimmer switches phase, while all required output current is provided during the operation of the dimmer, resulting in a large charging peak current at the moment the dimmer works, which oscillates with the inductance and capacitance inside the driver, causing the input current to oscillate through zero. In order to reduce the instantaneous charging peak current of the dimmer, the resistors RS53A, RS53B and RS53C are used to input the voltage waveform to detect the dimmer, and the compensation time is controlled by the resistor RS54 and the transistor QS53, while the resistors RS55, RS56 and the filter capacitor CS53 provide the compensation size, and then the resistors RS34A and RS34B inject a certain current into the peak detection pin Isense of the chip IW3605, so that the driving duty cycle during the chip opening period is reduced from >85% to about <60%, so that the instantaneous peak value of the dimmer charging is reduced by about 1/3, and the output energy needs to be maintained after opening, so the input current oscillation peak-to-peak amplitude becomes narrower, so that the lower limit mean value of the current oscillation during the entire dimming period is raised above the zero potential, and the oscillation does not exceed zero, thereby maintaining a stable thyristor working process. Solve the problem of flicker under small holding current.

The present invention overcomes the technical problems in the prior art that when the thyristor dimming driver is adjusted to a smaller angle, the input current oscillates and crosses zero easily, causing low-end flicker, and the maintenance current of the thyristor dimming driver is difficult to meet. A ripple removal circuit is used to achieve the purpose of current output without flashing, and the dimming compatibility is reliable and the price is low; a valley compensation circuit is used to reduce the turn-on current peak value when the input current is at the valley bottom, reduce the peak oscillation amplitude, and directly raise the zero crossing point in the thyristor dimming state to a certain height, so that the input current oscillation does not cross zero during the thyristor adjustment process, and solves the flicker problem under a small maintenance current; an input voltage waveform detection circuit is used to extract the input voltage valley signal to control the valley compensation circuit, and the input current waveform is corrected at the valley bottom of each large cycle to improve the input current waveform to be closer to a sine wave, thereby improving the power factor PF, reducing the total harmonic THD, and the sub-harmonics meet the requirements of European certification standards.

The specific embodiments described herein are merely examples of the spirit of the present invention. A person skilled in the art of the present invention may make various modifications or additions to the specific embodiments described or replace them in a similar manner, but this will not deviate from the spirit of the present invention or exceed the scope defined by the appended claims.

Although this article uses terms such as AC power supply, rectifier tube, power supply VCC, compensation current, etc. more frequently, it does not exclude the possibility of using other terms. These terms are used only to more conveniently describe and explain the essence of the present invention.

Claims (7)

1. The stroboscopic-free dimming driver is characterized by comprising an insurance module (1), a rectification module (2), a dimming driving module (3), a valley compensating unit (4), a filtering module (5), an input current waveform detection circuit (6), a power supply circuit (7), an electrolytic filtering circuit (8) and a ripple removing circuit (9), wherein an input AC power supply is connected with the input end of the insurance module (1), the output end of the insurance module (1) is sequentially connected with the rectification module (2) and the filtering module (5), the output end of the filtering module (5) is connected with the input end of the input current waveform detection circuit (6), one end of the output end of the input current waveform detection circuit (6) is connected with the input end of the power supply circuit (7), the other end of the input current waveform detection circuit outputs a dimming signal to the dimming driving module (3), the output end of the power supply circuit (7) is connected with the input end of the dimming driving module (3), the output end of the driving module (3) is sequentially connected with the electrolytic filtering circuit (8) and the ripple removing circuit (9), and the output end of the driving module (3) is sequentially connected with the input end of the valley compensating unit (4);

The ripple removing circuit (9) comprises a strobe-free ripple removing chip US51, a resistor RS71A, a resistor RS71B, a resistor RS73A, a resistor RS73B, a resistor RS74A, a resistor RS74B, a resistor RS74C, a resistor RS74D, a resistor RS74E, a capacitor CS71, a capacitor CS72, a capacitor CS73, a capacitor CS74, a voltage stabilizing diode ZS71, a diode DS71, a MOS tube Q71 and an inductor L42, one path of VIN pin of the strobe-free ripple removing chip US51 is connected with a ground terminal after passing through the capacitor CS71, the other path of VIN pin is connected with an electrolytic filter circuit (8) after passing through the resistor RS71B and the resistor RS71A, the other path of VIN pin is connected with a negative electrode of the voltage stabilizing diode ZS71, the positive electrode of the voltage stabilizing diode ZS71 is connected with a ground terminal, the GND pin of the strobe-free ripple removing chip US51 is directly connected with the ground terminal, one path of VC pin of the strobe-free ripple removing chip US51 is connected with the ground terminal after passing through the capacitor CS72, the other path of VIN pin is connected with the ground terminal after passing through the resistor RS72, the VLMT pin of the non-stroboscopic ripple-removing chip US51 is connected with the ground after passing through a resistor RS73B, the other path is connected with one end of a resistor RS73A, the other end of the resistor RS73A is connected with the positive electrode of a diode DS71 and the same-name end of a secondary winding of an inductor L42, the negative electrode of the diode DS71 is connected with an electrolytic filter circuit (8), the other path is connected with the same-name end of a primary winding of the inductor L42, the different-name end of the primary winding of the inductor L42 is connected with an X41A port, the different-name end of the secondary winding of the inductor L42 is connected with an X41A port, the same-name end of the secondary winding of the inductor L42 is also connected with the drain electrode of a MOS tube Q71, the grid electrode of the MOS tube Q71 is connected with the VG pin of the non-stroboscopic ripple-removing chip US51, the VG pin of the non-stroboscopic ripple-removing chip US51 is connected with the ground after passing through a capacitor CS74, and resistors RS74A and RS74B are connected between the source and the ground, the parallel circuit of a resistor RS74C, a resistor RS74D and a resistor RS74E, wherein one end of the resistor RS74A and one end of the resistor RS74B are connected as an input end and are connected with a VS pin of the strobe-free ripple removing chip US 51;

The valley bottom compensation unit (4) comprises a valley bottom compensation circuit and an input voltage waveform detection circuit (401), the valley bottom compensation circuit comprises a resistor RS54, a resistor RS55, a resistor RS56, a capacitor CS53 and a triode QS53, the input voltage waveform detection circuit (401) comprises a resistor RS53A, a resistor RS53B and a resistor RS53C, one end of the resistor RS53A IS connected with VDCBUS ends, namely connected with a rectifying module (2), the other end of the resistor RS53A IS connected with one end of the resistor RS53B, the other end of the resistor RS53B IS connected with the base electrode of the triode QS53 after passing through the resistor RS54, one end of the other end of the resistor RS53B IS connected with the ground end after passing through the resistor RS53B, the other end of the resistor RS53 IS connected with the negative electrode of the voltage stabilizing diode ZS53, the positive electrode of the triode ZS53 IS connected with the ground end, the collector of the triode QS53 IS connected with the power VCC end after passing through the resistor RS55, the other end of the triode QS53 IS connected with the capacitor CS, and the other end of the triode QS53 IS connected with the ground.

2. The stroboscopic-free dimming driver with input valley compensation according to claim 1, wherein the dimming driving module (3) comprises a silicon controlled rectifier dimmer (301) and a peripheral circuit thereof, the silicon controlled rectifier dimmer (301) comprises a single-stage silicon controlled rectifier dimming constant current chip US31, the peripheral circuit comprises a resistor RS35A, a resistor RS35B, a resistor RS35C, a resistor RS34A, a resistor RS34B, a resistor RS34C, a resistor RS32B, a resistor RS32A, a resistor RS32C, a resistor RS32D, a resistor RS32E, a diode DS31, a MOS transistor Q41, a capacitor C43, a capacitor CS61, a capacitor CS34, a capacitor C61, an inductor L43, an inductor L44 and an inductor L41C, a VCC pin of the single-stage silicon controlled rectifier dimming constant current chip US31 is connected to a power supply terminal, a VCC pin is connected to one terminal of the capacitor CS61, a positive terminal of the capacitor C61, and a VCC pin is connected to a power supply circuit (7), the other end of the capacitor CS61 is connected with the GND pin of the single-stage thyristor dimming constant current chip US31, the GND pin of the single-stage thyristor dimming constant current chip US31 is connected with the negative electrode of the capacitor C61, the negative electrode of the capacitor C61 is connected with the ground end, the Output pin of the single-stage thyristor dimming constant current chip US31 is connected with one end of a resistor RS35A after passing through a resistor RS35B, the other end of the resistor RS35A is connected with the ground end after passing through the resistor RS35C, the other path is connected with the grid electrode of a MOS tube Q41, the negative electrode of the diode DS31 is connected with one end of the resistor RS35A, the positive electrode of the diode DS31 is connected with the other end of the resistor RS35A, the drain electrode of the MOS tube Q41 is connected with one end of an inductor L44, a parallel circuit of the resistor RS32A, the resistor RS32C, the resistor RS32D and the resistor RS32E is connected between the source electrode of the MOS tube Q41 and the two ends, the single-stage thyristor dimming constant current chip US31 comprises a Isence pin, a resistor RS32E, a resistor RS34A, a resistor RS34C, a switch K1, an IS end, a valley compensation unit (4), a MOS transistor Q41, a capacitor CS34, a capacitor C43, a capacitor Q41 drain electrode, a single-stage thyristor dimming constant current chip US31 VIN pin, an input current waveform detection circuit (6), an inductor L44 and a power supply circuit (7), wherein one pin of the single-stage thyristor dimming constant current chip US31 IS connected with one end of the resistor RS32E, the other pin of the single-stage thyristor dimming constant current chip US31 IS connected with one end of the resistor RS34A, the other end of the resistor RS34A IS connected with the ground end through the resistor RS34C and the switch K1, the other pin of the inductor L41C IS connected with the synonym end of the primary winding of the inductor L41C, and the homonym end of the primary winding of the inductor L41C IS connected with the power supply circuit (7).

3. The stroboscopic-free dimming driver with input valley compensation according to claim 2, wherein the electrolytic filter circuit (8) comprises a rectifier diode D43A, a rectifier diode D43B, a rectifier diode D43C, a capacitor C43A, a capacitor C43B, a capacitor C43C and a capacitor C31A, one path of the synonym end of the secondary winding of the inductor L41C in the dimming driving module (3) is connected with the positive electrode of the diode D43A, one path is connected with the positive electrode of the diode D43B, one path is connected with the positive electrode of the diode D43C, the same name end of the secondary winding of the inductor L41, the negative electrode of the capacitor C43A, the negative electrode of the capacitor C43B, the negative electrode of the capacitor C43D are connected with the ground end through the capacitor C31A, one path of the positive electrode of the diode D43B is connected with the positive electrode of the capacitor C43A, one path is connected with the positive electrode of the capacitor C43C 9 of the capacitor C, and one path is connected with the positive electrode of the capacitor C43C of the capacitor C is connected with the positive electrode of the capacitor C43D.

4. A stroboflash-free dimming driver using input valley compensation according to claim 1, wherein the rectifying module (2) comprises a rectifying circuit, the rectifying circuit is composed of four diodes DS11, DS12, DS13 and DS14, the anode of the diode DS13 and the anode of the diode DS14 are connected with the ground, the cathode of the diode DS11 and the cathode of the diode DS12 are connected as output ends, one path is connected with one end of a resistor RS53A of the input voltage waveform detecting circuit (401), the other path is connected with the same name end of an inductor L41A of the dimming driving module (3), and the anode of the DS11 is connected with the cathode of the DS14 and is connected with the safety module (1) as one input end.

5. The stroboscopic-free dimming driver using input valley compensation according to claim 4, wherein the filtering module (5) comprises a resistor RS21, a resistor RS23, a capacitor C21, a capacitor C22, a capacitor C23, a diode DS21, an inductor L21 and a thermistor VD21, one end of the inductor L21 is connected with one end of the resistor R23 after passing through the capacitor C22, one end of the resistor R23 is further connected with a cathode of the diode DS21, one way of the other end of the resistor R23 is connected with an anode of the diode DS21, the other way of the resistor R23 is connected with an anode of the diode DS14 of the rectifying module (2), a capacitor C21 is connected between a cathode of the diode DS12 of the rectifying module (2) and an anode of the diode DS14 in parallel, the other end of the inductor L21 is connected with one end of the capacitor C23, the other end of the capacitor C23 is connected with a ground, both ends of the capacitor C23 are connected with the thermistor VD21 in parallel, and both ends of the inductor L21 are connected with the resistor RS21 in parallel.

6. The stroboscopic dimming driver with input valley compensation according to claim 4, wherein the insurance module (1) comprises a capacitor C11, an insurance resistor R11, an EMI common-mode inductor L12 and a thermistor D11, the nominated end of the primary winding of the EMI common-mode inductor L11 is connected to the X11A interface of the input AC power supply, one end of the insurance resistor R11 is connected to the X11B interface of the input AC power supply, the other end of the insurance resistor R11 is connected to the nominated end of the secondary winding of the EMI common-mode inductor L11, the nominated end of the primary winding of the EMI common-mode inductor L11 is connected to the nominated end of the primary winding of the EMI common-mode inductor L12, one end of the thermistor D11 is connected to the nominated end of the secondary winding of the EMI common-mode inductor L12, the other end of the thermistor D11 is connected to the nominated end of the common-mode inductor L11, and the other end of the common-mode inductor DS of the common-mode inductor L12 is connected to the common-mode winding of the secondary winding of the EMI common-mode inductor L12, and the common-mode diode DS is connected to the other end of the common-mode inductor L11.

7. The strobe-free dimming driver according to claim 2 or 5, wherein the input current waveform detection circuit (6) comprises a resistor RS31A, a resistor RS31B, a resistor RS31C and a capacitor CS31, the power supply circuit (7) comprises a resistor RS62A, a resistor RS62B and a MOS transistor QS62, a drain electrode of the MOS transistor QS62 is connected to one end of the resistor RS62A through the resistor RS62B, one end of the resistor RS62A is connected to a homonymous end of a primary winding of the inductor L41C, the other end of the resistor RS62A is connected to one end of the inductor L21 in the filter module (5), a source electrode of the MOS transistor QS62 is connected to a VCC pin of the single-stage thyristor dimming constant current chip US31, one end of the resistor RS31A is connected to a VDCBUS end, the other end of the resistor RS31A is connected to one end of the resistor RS31C through the resistor RS31B, one end of the other end of the resistor QS 31C is connected to a gate electrode of the MOS transistor RS62, and the other end of the resistor is connected to one end of the capacitor CS33 through the capacitor CS 31.