CN112770452A

CN112770452A - Wide voltage isolation AC-DC multichannel driver and LED lighting equipment

Info

Publication number: CN112770452A
Application number: CN202110114152.4A
Authority: CN
Inventors: 胡炎申
Original assignee: Moso Power Supply Technology Co ltd
Current assignee: Moso Power Supply Technology Co ltd
Priority date: 2021-01-27
Filing date: 2021-01-27
Publication date: 2021-05-07

Abstract

The application discloses a wide voltage isolation AC-DC multichannel driver and LED lighting equipment, wherein the wide voltage isolation AC-DC multichannel driver comprises an isolation PFC main converter and a plurality of DC-DC auxiliary converters; the isolated PFC main converter comprises a PFC power conversion unit, a voltage converter and a main output port, wherein the voltage converter comprises a first main winding, a second main winding, a first auxiliary winding and a second auxiliary winding; the DC-DC auxiliary converter comprises an auxiliary input port and an auxiliary output port; the output end of the PFC power conversion unit is connected with the first main winding; the first auxiliary winding is connected with the main output port; the second auxiliary winding is respectively connected with the auxiliary input ports of the plurality of DC-DC auxiliary converters; and the auxiliary output ports of the DC-DC auxiliary converters are connected with the main output port in series to form a plurality of total output ports. And part of electric energy provided by the alternating current power supply is transmitted to the load in a single-stage conversion mode, and part of electric energy is transmitted to the load in a two-stage conversion mode. The power consumption is reduced, and the overall conversion efficiency is improved.

Description

Wide voltage isolation AC-DC multichannel driver and LED lighting equipment

Technical Field

The present disclosure relates to circuit technologies, and particularly to a wide voltage isolation type alternating current-direct current (AC-DC) constant current driver and a Light Emitting Diode (LED) lighting device.

Background

The LED is applied to lighting devices, and has the advantages of wide color gamut, high brightness, large viewing angle, low power consumption, long service life, and the like, so that the LED lighting devices are widely applied to various lighting display fields. Such as the common stock exchange and financial information display, airport flight dynamic information display, port and station passenger guidance information display, stadium information display, road traffic information display, electric power scheduling, vehicle dynamic tracking and other scheduling command center information display, market shopping center and other service fields business propaganda information display, advertising media products and the like.

Generally, the LED lighting device needs a driving power supply for driving when working normally, and the driving power supply is generally a constant current driver. The current constant current driver comprises a single stage and a plurality of stages. Although the single-stage constant-current driver has a simple structure and low cost, the single-stage constant-current driver cannot simultaneously give consideration to input high power factor and output low ripple, and even the power tube still has overhigh voltage or current stress. Therefore, a multi-stage constant current driver is generally selected in the industry, wherein two stages are common, and in the two-stage constant current driver, a front-stage PFC converter is used for adjusting an input power factor and balancing input and output energy; and the rear-stage direct current (DC-DC) auxiliary converter is used for adjusting the output voltage and reducing the output ripple voltage or current.

However, when the two-stage constant current driver is applied to independent dimming of multi-channel loads, a plurality of rear-stage DC-DC converters and a front-stage PFC converter are required to be cascaded, and the ac output of each channel can be converted into a total output after two-stage full power conversion, which causes a large power consumption and a low overall conversion rate.

Disclosure of Invention

The application aims to provide a wide voltage isolation AC-DC multi-channel driver and an LED lighting device, power consumption is reduced, and overall conversion efficiency is improved.

A first aspect of the application provides a wide voltage isolation AC-DC multi-channel driver comprising: isolating the PFC main converter and the plurality of DC-DC auxiliary converters; the isolated PFC main converter comprises a PFC power conversion unit, a voltage converter and a main output port, wherein the voltage converter comprises a first main winding, a second main winding, a first auxiliary winding and a second auxiliary winding; the first main winding and the first auxiliary winding are mutually induced, and the second main winding and the second auxiliary winding are mutually induced; the DC-DC auxiliary converter comprises an auxiliary input port and an auxiliary output port; the output end of the PFC power conversion unit is connected with the first main winding; the first auxiliary winding is connected with the main output port; the second auxiliary winding is respectively connected with the auxiliary input ports of the plurality of DC-DC auxiliary converters; the auxiliary output ports of the DC-DC auxiliary converters are respectively connected with the main output port in series to form a plurality of total output ports; the PFC power conversion unit converts the received alternating current into direct current and outputs the direct current to the voltage converter; after receiving direct current, the voltage converter converts main voltage through the first main winding and the first auxiliary winding, outputs the main voltage to a main output port, and the main output port transmits the main voltage to a main output port; converting an auxiliary voltage through the second main winding and the second auxiliary winding, and respectively outputting the auxiliary voltage to auxiliary input ports of the plurality of DC-DC auxiliary converters; the DC-DC auxiliary converter receives the auxiliary voltage from the auxiliary input port, processes the auxiliary voltage and outputs the auxiliary voltage to the auxiliary output port, the auxiliary output port transmits the auxiliary voltage to the main output port, and the main output port receives the main voltage and the auxiliary voltage and outputs the main voltage.

In one embodiment, the wide voltage isolation AC-DC multi-channel driver further comprises: a PFC controller; the isolated PFC main converter further comprises: a main power switch tube; the main power switch tube is connected with the first main winding; the PFC controller comprises a main feedback port, a first main acquisition port, a main control port, a main reference voltage port and a main reference sawtooth wave signal port; the main feedback port is connected with the auxiliary output port, the first main acquisition port is connected with the second main winding, and the main control port is connected with the control end of the main power switch tube; the auxiliary output port transmits the auxiliary voltage to the main feedback port, and the PFC controller receives the auxiliary voltage from the main feedback port, the voltage of the second main winding from the first main acquisition port, the main reference voltage from the main reference voltage port and the main reference sawtooth wave signal from the main reference sawtooth wave signal port; comparing the auxiliary voltage with the main reference voltage to form a voltage error signal; comparing the voltage error signal with the main reference sawtooth wave signal to form a stop pulse signal; forming a start pulse signal based on the voltage of the second main winding; and controlling the on and off of the main power switch tube by using the stop pulse signal and the start pulse signal.

In one embodiment, the PFC controller further comprises a second primary acquisition port; the second main acquisition port is connected with the main power switch tube; the PFC controller also receives the voltage of a main power switch tube from the second main acquisition port; comparing the voltage error signal with the main reference sawtooth wave signal to form a stop pulse signal includes: and comparing the voltage error signal with the voltage of the main power switch tube to form a comparison result, and comparing the main reference sawtooth wave signal with the comparison result to form a stop pulse signal.

In one embodiment, a PFC controller includes a main reference voltage source, a main reference sawtooth signal source, a first main comparator, a second main comparator, a third main comparator, and a flip-flop; the trigger is provided with an S port, a Q port and an R port; the negative input end of the first main comparator is connected with the main feedback port, the positive input end of the first main comparator is connected with a main reference voltage source through a main reference voltage port, and the output end of the first main comparator is connected with the positive input end of the second main comparator; the negative input end of the second main comparator is connected with the second main acquisition port, and the output end of the second main comparator is connected with the positive input end of the third main comparator; the negative input end of the third main comparator is connected with the main reference sawtooth wave signal source through a main reference sawtooth wave signal port, and the output end of the third main comparator is connected with the R port; the Q port is connected with the main control port, and the S port is connected with the first main acquisition port; the first master comparator is to: comparing the auxiliary voltage with the main reference voltage to form a voltage error signal; the second master comparator is to: comparing the voltage error signal with the voltage of the main power switch tube to form a comparison result; the third master comparator is to: comparing the main reference sawtooth wave signal with the comparison result to form a stop pulse signal; the trigger is used for: forming a start pulse signal based on the voltage of the second main winding; and controlling the on and off of the main power switch tube by using the stop pulse signal and the start pulse signal.

In one embodiment, the wide voltage isolation AC-DC multi-channel driver further comprises: a DC-DC controller; the DC-DC auxiliary converter further includes: an auxiliary power switch tube; the DC-DC controller comprises an auxiliary feedback port, an auxiliary control port, an auxiliary reference current port and an auxiliary reference sawtooth wave signal port; the auxiliary feedback port is connected with the auxiliary output port, and the auxiliary control port is connected with the control end of the auxiliary power switch tube; the main output port receives the main voltage and the auxiliary voltage and then outputs a total current; the total current is transmitted to the auxiliary feedback port; after the DC-DC controller receives the total current from the auxiliary feedback port, the auxiliary reference current from the auxiliary reference current port and the auxiliary reference sawtooth wave signal from the auxiliary reference sawtooth wave signal port, comparing the total current with the auxiliary reference current to form a voltage error signal; and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal, and transmitting the control signal to the control end of the auxiliary power switch tube.

In one embodiment, the DC-DC controller further comprises: a PWM digital dimming signal port; the DC-DC controller also receives a PWM digital dimming signal from a PWM digital dimming signal port; the step of comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal comprises: and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal, and forming a control signal based on the comparison signal and the PWM digital dimming signal.

In one embodiment, a DC-DC controller includes: the circuit comprises a first auxiliary comparator, a second auxiliary comparator, an AND gate circuit, an auxiliary reference current source, an auxiliary reference sawtooth wave signal source and a PWM digital dimming signal source; the negative input end of the first auxiliary comparator is connected with the auxiliary feedback port, the positive input end of the first auxiliary comparator is connected with the auxiliary reference current source through the auxiliary reference current port, and the output end of the first auxiliary comparator is connected with the positive input end of the second auxiliary comparator; the negative input end of the second auxiliary comparator is connected with the auxiliary reference sawtooth wave signal source through an auxiliary reference sawtooth wave signal port, the output end of the second auxiliary comparator is connected with one input end of the AND gate circuit, and the other input end of the AND gate circuit is connected with the PWM digital dimming signal source through a PWM digital dimming signal port; the output end of the AND gate circuit is connected with the auxiliary control port; the first auxiliary comparator is for: comparing the total current with the auxiliary reference current to form a voltage error signal; comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal; the second auxiliary comparator is for: comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal; and the AND gate circuit is used for: and (4) carrying out AND calculation on the comparison signal and the PWM digital dimming signal to form a control signal, and transmitting the control signal to the control end of the auxiliary power switch tube.

In one embodiment, the isolated PFC main converter comprises a flyback converter or a forward converter.

In one embodiment, the DC-DC auxiliary converter includes one of a buck converter, a boost converter, a buck-boost converter, a flyback converter, a forward converter, a buck-boost converter, a.

A second aspect of the application provides an LED lighting device comprising the wide voltage isolated AC-DC multi-channel driver of any one of the first aspects of the application.

The wide-voltage isolation AC-DC multi-channel driver provided by the application utilizes four windings to form an isolation structure, and a plurality of total output port connections are formed in the driver of the isolation structure and can be connected with a plurality of loads, so that a plurality of channels are proved, and in each channel, the output power of a PFC power conversion unit to the load part is only subjected to single-stage conversion. The DC-DC auxiliary converter provides partial power for the load to undergo two-stage conversion, namely only partial power undergoes two-stage conversion as a whole, so that compared with a mode that all output power of each channel is converted twice, the mode that only partial power undergoes two-stage conversion in each channel can reduce power consumption. Therefore, even if a multi-channel load is connected, the overall efficiency is high. Therefore, the power consumption is reduced, and the overall conversion efficiency is improved.

Drawings

In order to more clearly illustrate the technical solution of the present application, the drawings needed to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic diagram of a wide voltage isolation AC-DC multichannel driver provided by one embodiment of the present application;

FIG. 2 is a schematic diagram of a wide voltage isolation AC-DC multichannel driver provided by another embodiment of the present application;

FIG. 3 is a schematic diagram of a wide voltage isolation AC-DC multichannel driver provided by another embodiment of the present application;

FIG. 4 is a schematic diagram of a wide voltage isolation AC-DC multichannel driver provided by another embodiment of the present application;

FIG. 5 is a schematic diagram of a DC-DC auxiliary converter provided in an alternative embodiment of the present application;

FIG. 6 is a schematic diagram of a DC-DC auxiliary converter provided in an alternative embodiment of the present application;

FIG. 7 is a schematic diagram of a DC-DC auxiliary converter provided in an alternative embodiment of the present application;

fig. 8 is a schematic diagram of a DC-DC auxiliary converter provided in an alternative embodiment of the present application.

Description of reference numerals:

the isolated PFC controller comprises an isolated PFC main converter 10, a PFC power conversion unit 11, a voltage converter 12, a first main winding 121, a first auxiliary winding 122, a second main winding 123, a second auxiliary winding 124, a DC-DC auxiliary converter 20, a PFC controller 30, a DC-DC controller 40, an alternating current power supply 50, a load 60,

main input ports

1 and 2,

main output ports

3 and 4,

auxiliary input ports

5 and 6 and

auxiliary output ports

7 and 8.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application.

Referring to fig. 1 to 8, an embodiment of the present application provides a wide voltage isolation AC-DC multichannel driver, which includes an isolation PFC main converter 10 and a plurality of DC-DC auxiliary converters 20. Plural here means two or more.

The isolated PFC main converter 10 comprises a PFC power conversion unit 11, a voltage converter 12 and a main output port, wherein the voltage converter 12 comprises a first main winding 121, a second main winding 123, a first auxiliary winding 122 and a second auxiliary winding 124; the first main winding 121 and the first auxiliary winding 122 mutually induce, and the second main winding 123 and the second auxiliary winding 124 mutually induce; the DC-DC auxiliary converter 20 includes an auxiliary input port and an auxiliary output port. The voltage converter 12 may be a transformer or inductor T1 of the dual winding type having a primary winding and a secondary winding.

Specifically, the output end of the PFC power conversion unit 11 is connected to one end of the first main winding 121; the first auxiliary winding 122 is connected to the main output port; the auxiliary windings are respectively connected with the auxiliary input ports of the plurality of DC-DC auxiliary converters 20; the auxiliary output ports of the plurality of DC-DC auxiliary converters 20 are respectively connected in series with the main output port to form a plurality of total output ports.

After the PFC power conversion unit 11 converts the received ac power into dc power, the main voltage is converted by the first main winding 121 and the first auxiliary winding 122, and is output to the main output port, which transmits the main voltage to the main output port; the auxiliary voltage is converted by the second main winding 123 and the second auxiliary winding 124, and is respectively output to the auxiliary input ports of the plurality of DC-DC auxiliary converters 20; the DC-DC auxiliary converter 20 receives the auxiliary voltage from the auxiliary input port, processes the auxiliary voltage, and outputs the processed auxiliary voltage to the auxiliary output port, the auxiliary output port transmits the auxiliary voltage to the main output port, and the main output port receives the main voltage and the auxiliary voltage and outputs the main voltage.

It will be appreciated that the isolated PFC main converter 10 also includes a main input port. In application, the main input port is connected to an ac power source 50, and each of the main output ports is connected to a load 60. Of course, the load 60 may be any device that needs to be powered, and in the embodiment of the present application, a string of LEDs is used as the load 60. The main output port provides the main voltage to the load 60 and the auxiliary output port provides the auxiliary voltage to the load 60, so that the total voltage of the load 60 is the sum of the main voltage and the auxiliary voltage. The main output port forms a direct current bus.

Specifically, n DC-DC auxiliary converters 20 are included to form n total output ports, where n is a positive integer greater than or equal to 2. The main input port of the isolated PFC main converter 10 outputs a main voltage Vo, the auxiliary output ports of the n DC-DC auxiliary converters 20 output n auxiliary voltages Vo21 to Vo2n, respectively, the total voltages of the n total output ports are Vo + Vo21 to Vo + Vo2n, respectively, and the total currents of the n total output ports are Io1 to Ion, respectively. The n total output ports are respectively connected with the n LED lamp strings LED1 to LEDn.

As can be seen from the above, in the present embodiment, how many total output ports are formed, how many loads 60 can be correspondingly connected, and the total voltage of each load 60 is the sum of the main voltage and the auxiliary voltage connected to each load. That is, the main voltage supplied to each load 60 is converted by only a single stage, and the auxiliary voltage supplied to each load 60 is converted by two stages, one stage and two stages.

Therefore, the PFC power conversion unit 11 only performs a single-stage conversion on the partial output power to the load 60. The DC-DC auxiliary converter 20 provides part of the power to the load 60, and although the power provided by the DC-DC auxiliary converter 20 is converted by two stages, part of the power is converted by two stages as a whole, so that compared with a mode in which all the output power is converted by two stages, the mode in which part of the power is converted by two stages can reduce power consumption and improve conversion efficiency.

In an alternative embodiment, in which the resistances of the first main winding 121 and the second main winding 123 are equal, the resistance of the first auxiliary winding 122 is smaller than that of the second auxiliary winding 124, so that the main voltage is larger than the auxiliary voltage and the output power of the main output port is larger than that of the auxiliary output port in the same channel under the condition of the same current. Therefore, less part of output power is converted by two stages, so that the power consumption can be reduced, and the conversion efficiency can be improved.

Specifically, assume that the conversion efficiency of the isolated PFC main converter 10 is η_PFCThe conversion efficiency of each DC-DC auxiliary converter 20 is eta_DC-DC，P_PFC、P_DC-DC、P_outFor the output power of the isolated PFC main converter 10, the output power of the DC-DC auxiliary converter 20, and the overall output power, respectively, the overall efficiency is:

let P_DC-DC＝％xP_outAnd then:

is additionally provided with eta_DC-DC90%, the overall conversion efficiency η_total＝98.9％xη_PFC。

As can be seen from the above, if the output power ratio of the DC-DC auxiliary converter 20 is 10%, even if the conversion efficiency of the DC-DC auxiliary converter 20 is as low as 90%, the overall efficiency η is_totalClose to 99%, very close to the conversion efficiency of a pure single stage converter directly provided to the LED string. Even if a plurality of DC-DC auxiliary converters 20 are present, the overall efficiency is still relatively high, and for example, the overall efficiency can reach 99% by 99% with two DC-DC auxiliary converters 20. Therefore, the wide voltage isolation AC-DC multichannel driver provided by the embodiment of the application has lower power loss and can improve the overall efficiency.

In the embodiment of the application, most of the electric energy provided by the ac power supply 50 is transmitted to the LED light string through single conversion, and a small part of the electric energy is transmitted to the LED light string through primary and secondary conversion. Therefore, the power consumption is reduced, and the overall conversion efficiency is improved. In addition, because the DC-DC auxiliary converter 20 only converts a small part of electric energy, the voltage and current stress of the internal devices is also small, and the cost of the components can be reduced.

In one embodiment, referring to fig. 2 and 3, the wide voltage isolation AC-DC multi-channel driver further includes a PFC controller 30; the isolated PFC main converter 10 further includes a main power switch Q1. The main power switch Q1 is connected to the first main winding 121.

The PFC controller 30 comprises a main feedback port a1, a first main acquisition port a2, a main control port a3, a main reference voltage port a5 and a main reference sawtooth signal port a 4; the main feedback port a1 is connected with the auxiliary output port, the first main acquisition port a2 is connected with the second main winding 123, and the main control port a3 is connected with the control end of the main power switch tube Q1.

The auxiliary output port transmits the auxiliary voltage to the main feedback port a1, and the PFC controller 30 receives the auxiliary voltage from the main feedback port a1, the voltage from the second main winding 123 of the first main acquisition port a2, the main reference voltage from the main reference voltage port a5, and the main reference sawtooth signal from the main reference sawtooth signal port a 4. Comparing the auxiliary voltage with the main reference voltage to form a voltage error signal; comparing the voltage error signal with the main reference sawtooth wave signal to form a stop pulse signal; forming a start pulse signal based on the voltage of the second main winding 123; the stop pulse signal and the start pulse signal are used to control the on and off of the main power switch tube Q1.

The stop pulse signal and the start pulse signal may form a Pulse Width Modulation (PWM) signal, which is used to control the main power switch Q1.

That is, the auxiliary voltage of the auxiliary output port is fed back to the PFC controller 30 through the main feedback port a1, the main reference voltage is supplied to the PFC controller 30 through the main reference voltage port a5, and the PFC controller 30 compares the auxiliary voltage and the main reference voltage and then forms a voltage error signal. Then, the PFC controller 30 compares the voltage error signal with the main reference sawtooth signal to generate a stop pulse signal; the PFC controller 30 may then control the turn off of the main power switch Q1 using the stop pulse signal.

The voltage of the second main winding 123 is fed back to the PFC controller 30 through the first main collecting port a2, and the PFC controller 30 generates a start pulse signal by using the voltage of the second main winding 123; the PFC controller 30 then uses the start pulse signal to control the turn-on of the main power switch Q1.

The control mode can control the auxiliary voltage in a closed loop mode, and can also realize that the input current and the output voltage are sine waves with the same frequency and the same phase so as to achieve power factor correction and better power factor and realize zero pollution to a power grid.

In one embodiment, the PFC controller 30 further includes a second primary acquisition port a 6; the second primary collection port a6 is connected to the primary power switch Q1. The PFC controller 30 also receives the voltage from the main power switch Q1 of the second main acquisition port a 6. Comparing the voltage error signal with the main reference sawtooth wave signal to form a stop pulse signal includes: and comparing the voltage error signal with the voltage of the main power switch tube Q1 to form a comparison result, and comparing the main reference sawtooth wave signal with the comparison result to form a stop pulse signal.

That is, the PFC controller 30 compares the voltage error signal with the voltage of the main power switch Q1 before comparing the main reference sawtooth signal with the voltage error signal, and then compares the comparison result with the main reference sawtooth signal. The peak current of the main power switch Q1 can thus be controlled.

In an alternative embodiment, referring to fig. 4, the isolated PFC main converter 10 further includes a first main acquisition unit and a second main acquisition unit; the second primary pick-up is connected to the primary power switch Q1 and the first primary pick-up is connected between the first primary pick-up port a2 and the second primary winding 123. The second main collecting port a6 collects the voltage of the main power switch tube Q1 through the second main collecting piece, and the first main collecting port a2 collects the voltage of the second main winding 123 through the first main collecting piece. Optionally, the first main collecting element and the second main collecting element may be a resistor Rdem and a resistor Ri, respectively.

The first main collecting part and the second main collecting part are arranged, so that the PFC can control and accurately collect required signals, and the precision of the PFC in controlling the main power switch tube Q1 is improved.

In one embodiment, the PFC controller 30 includes a main reference voltage source, a main reference sawtooth signal source, a first main comparator U1, a second main comparator U2, a third main comparator U3, and a flip-flop U4; flip-flop U4 has an S port, a Q port, and an R port.

Specifically, the negative input terminal of the first main comparator U1 is connected to the main feedback port a1, the positive input terminal of the first main comparator U1 is connected to a main reference voltage source through the main reference voltage port a5, and the output terminal of the first main comparator U1 is connected to the positive input terminal of the second main comparator U2; the negative input end of the second main comparator U2 is connected with the second main acquisition port a6, and the output end of the second main comparator U2 is connected with the positive input end of the third main comparator U3; the negative input end of the third main comparator U3 is connected with a main reference sawtooth wave signal source through a main reference sawtooth wave signal port a4, and the output end of the third main comparator U3 is connected with an R port; the Q port is connected to the primary control port a3 and the S port is connected to the first primary acquisition port a 2.

The first master comparator U1 is configured to: comparing the auxiliary voltage with the main reference voltage to form a voltage error signal; the second master comparator U2 is configured to: comparing the voltage error signal with the voltage of the main power switch tube Q1 to form a comparison result; the third master comparator U3 is configured to: comparing the main reference sawtooth wave signal with the comparison result to form a stop pulse signal; the flip-flop U4 is used to: forming a start pulse signal based on the voltage of the second main winding 123; the stop pulse signal and the start pulse signal are used to control the on and off of the main power switch tube Q1.

In detail, after the first comparator receives the auxiliary voltage and the main reference voltage of the main output port, the auxiliary voltage and the main reference voltage of the main output port are compared, and then a voltage error signal is output to the second comparator. The second comparator receives the voltage error signal and the voltage of the main power switch tube Q1, controls the peak current of the main power switch tube Q1, compares the voltage error signal with the voltage of the main power switch tube Q1, and outputs the comparison result to the third comparator. After receiving the comparison result and the main reference sawtooth wave signal, the third comparator compares the comparison result with the main reference sawtooth wave signal and outputs a signal to the R end of the contactor; the contactor generates a stop pulse signal according to the one signal, and the stop pulse signal is output to the control end of the main power switch tube Q1 through the Q end of the contactor so as to control the turn-off of the main power switch tube Q1. After receiving the voltage of the second main winding 123 through the S terminal, the contactor generates a start pulse signal by using the voltage of the second main winding 123; then, the start pulse signal is output to the control terminal of the main power switch Q1 through the Q terminal to control the main power switch Q1 to be turned on.

By using the PFC controller 30 with the above structure, the isolated PFC main converter 10 can be precisely controlled, and the isolated PFC main converter is simple to manufacture, low in cost and high in control precision.

In one embodiment, the wide voltage isolation AC-DC multi-channel driver further comprises: a DC-DC controller 40; the DC-DC auxiliary converter 20 further includes an auxiliary power switch Q2; the DC-DC controller 40 includes an auxiliary feedback port b1, an auxiliary control port b2, an auxiliary reference current port b3, and an auxiliary reference sawtooth signal port b 4; the auxiliary feedback port b1 is connected with the auxiliary output port, and the auxiliary control port b2 is connected with the control end of the auxiliary power switch tube Q2.

The main output port receives the main voltage and the auxiliary voltage and then outputs a total current; the total current is transmitted to the secondary feedback port b 1; after the DC-DC controller 40 receives the total current from the auxiliary feedback port b1, the auxiliary reference current from the auxiliary reference current port b3, and the auxiliary reference sawtooth signal from the auxiliary reference sawtooth signal port b4, the total current and the auxiliary reference current are compared to form a voltage error signal; and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal, and transmitting the control signal to the control end of the auxiliary power switch tube Q2. The control strategy can realize closed-loop control of the current of the LED lamp string. The control signal of the auxiliary power switch Q2 is a Pulse Width Modulation (PWM) control signal.

In addition, the control strategy of the PFC controller 30 and the control strategy of the DC-DC controller 40 are combined, so that the main voltage of the main output port and the auxiliary voltage ripple of the auxiliary output port are reversely superimposed and offset, and the ripple of the total output voltage Vo is reduced, thereby reducing the ripple of the current of the LED string.

In detail, the main voltage Vo1 and the auxiliary voltage Vo2 have the purpose of reverse superposition of ripples to reduce or cancel power frequency ripples. The main voltage Vo1 of the main output port has a power frequency ripple, but is connected in series with the auxiliary voltage Vo2 of the auxiliary output port, and the reference signal in the current feedback loop of the DC-DC controller 40 of the DC-DC auxiliary converter 20 is an auxiliary reference current Iref, which is a direct current reference signal.

In addition, the switching frequency of the DC-DC auxiliary converter 20 is much higher than the switching frequency of the isolated PFC main converter 10, so the dynamic response speed of the DC-DC auxiliary converter 20 is very fast, and theoretically, the total current io of the total output port formed by connecting the auxiliary output port and the main output port in series can be equal to Iref in real time, so the total current io is also infinitely close to a direct current value. Meanwhile, the main output port and the auxiliary output port are in series connection, so that the total current of the total output port formed by the series connection of the auxiliary output port and the main output port is equal to the current of the auxiliary output port, and the current of the auxiliary output port is a direct current value, so that the total current is also a direct current value, which is equivalent to the cancellation of power frequency ripples output by the main output port.

As can be seen from the above, the DC-DC auxiliary converter 20 is controlled by a fast loop, and the isolated PFC main converter 10 is controlled by a slow loop. In the application, in order to eliminate the power frequency ripple of the main output port, the main output port and the auxiliary output port are connected in series, so that the current of the main output port, the current of the auxiliary output port and the total current are equal.

The DC-DC controller 40 controls only the output current Ios, and the main voltage Vo1 or the total voltage Vo is controlled by the PFC controller 30. The reason for this is that if the amplitude of the total voltage output is smaller than the amplitude of the voltage for maintaining the normal operation of the load LED, the output DC current required by the load cannot be maintained by controlling the DC-DC controller 40 alone, so that on the one hand, the output voltage required by the load is high enough; on the other hand, when the total output voltage amplitude meets the load requirement, the DC-DC controller 40 maintains an output DC current required by the load, and the fast feedback loop of the DC-DC controller 40 makes the output current infinitely approach the DC value without the power frequency ripple. Therefore, the requirements of load working voltage and current can be met, and power frequency ripples can be eliminated.

In addition, the wide voltage isolation AC-DC multi-channel driver, the control strategy of the PFC controller 30 and the control strategy of the DC-DC controller 40 are combined, wherein the auxiliary voltage output by the auxiliary output module is fed back to the PFC controller 30, and the PFC controller 30 controls the isolation PFC main converter 10 based on the fed-back auxiliary voltage, thereby realizing the closed-loop control of the auxiliary voltage. Wherein the total current of the total output port is fed back to the DC-DC controller 40, and the DC-DC controller 40 controls the DC-DC converter based on the fed-back total current, thereby realizing a closed-loop control of the total current.

In summary, the auxiliary voltage is controlled to be a constant value by the PFC controller 30 in a closed-loop manner, and the total current is also controlled to be a constant value by the DC-DC controller 40 in a constant-current manner, so that the PFC controller 30 can indirectly adjust the magnitude of the main voltage under the condition of maintaining the total current to be constant, thereby widening the range of the total voltage. And because the main voltage is single-stage conversion, only the auxiliary voltage needs to be subjected to double-stage conversion, so that the number of required components is reduced, the heating degree is reduced, the cost is reduced, and the resources are saved.

The auxiliary voltage is controlled to be a fixed value through the PFC controller 30 in a closed loop manner, and the total current is also controlled to be a fixed value through the DC-DC controller 40 in a constant current manner, so that the PFC controller 30 can indirectly adjust the magnitude of the main voltage under the condition of maintaining the total current to be constant, thereby enabling the range of the total voltage to be wide. And because the main voltage is single-stage conversion, only the auxiliary voltage needs to be subjected to double-stage conversion, so that the number of required components is reduced, the heating degree is reduced, the cost is reduced, and the resources are saved.

In addition, the DC-DC controller 40 may also implement independent dimming of the multi-channel LED string. Specifically, each LED string corresponds to one DC-DC auxiliary converter 20, and each DC-DC auxiliary converter 20 correspondingly includes one auxiliary reference current port b3, so that an analog dimming manner can be implemented by adjusting the magnitude of the auxiliary reference current provided to the auxiliary reference current port b3, thereby implementing independent dimming of each LED string.

In one embodiment, the DC-DC controller 40 further includes a PWM digital dimming signal port. The DC-DC controller 40 also receives a PWM digital dimming signal from the PWM digital dimming signal port. The step of comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal comprises: and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal, and performing AND calculation on the comparison signal and the PWM digital dimming signal to form a control signal.

In this embodiment, a PWM digital dimming signal port is provided in each DC-DC controller 40 to increase the PWM digital dimming signal port to provide a PWM digital dimming signal, so that the independent dimming of the multi-channel LED light string can be realized by automatically adjusting the light of the LED light string connected to each DC-DC controller 40 through the respective PWM digital dimming signal port of each DC-DC controller 40 while realizing the closed-loop control.

In one embodiment, referring to fig. 4, the DC-DC auxiliary converter 20 further includes an auxiliary collecting member; the auxiliary acquisition element is connected between the auxiliary output port and the auxiliary feedback port b 1. The auxiliary output port collects voltage provided by the auxiliary output port and the main output port after being connected in series through the auxiliary collecting piece. Optionally, the auxiliary collecting element may be a resistor R3. The secondary collection element may convert the current of the LED string to a voltage that is provided to secondary feedback port b 1.

In one embodiment, the DC-DC controller 40 includes: the circuit comprises a first auxiliary comparator U5, a second auxiliary comparator U6, an AND gate circuit U7, an auxiliary reference current source, an auxiliary reference sawtooth wave signal source and a PWM digital dimming signal source.

Specifically, the negative input end of the first auxiliary comparator U5 is connected to the auxiliary feedback port b1, the positive input end of the first auxiliary comparator U5 is connected to the auxiliary reference current source through the auxiliary reference current port b3, and the output end of the first auxiliary comparator U5 is connected to the positive input end of the second auxiliary comparator U6; the negative input end of the second auxiliary comparator U6 is connected with an auxiliary reference sawtooth wave signal source through an auxiliary reference sawtooth wave signal port b4, the output end of the second auxiliary comparator U6 is connected with one input end of an AND gate circuit U7, and the other input end of the AND gate circuit U7 is connected with the PWM digital dimming signal source through a PWM digital dimming signal port; the output of the and circuit U7 is connected to the secondary control port b 2.

The first auxiliary comparator U5 is configured to: comparing the total current with the auxiliary reference current to form a voltage error signal; and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal. The second auxiliary comparator U6 is used to: comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal; and gate U7 is used to: and (4) forming a control signal after the comparison signal and the PWM digital dimming signal are subjected to AND calculation, and transmitting the control signal to the control end of the auxiliary power switch tube Q2.

Specifically, the first auxiliary comparator U5 receives the auxiliary reference current from the auxiliary reference current port b3 and the total current from the auxiliary feedback port b1, then compares the total current with the auxiliary reference current to form a voltage error signal, and outputs the voltage error signal to the second auxiliary comparator U6; the second auxiliary comparator U6 compares the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal and outputs the comparison signal to the and circuit U7 after receiving the voltage error signal and the auxiliary reference sawtooth wave signal, the and circuit U7 performs and calculation on the comparison signal and the PWM digital dimming signal after receiving the PWM digital dimming signal and the comparison signal to generate a control signal of the auxiliary power switch Q2, and outputs the control signal to the control terminal of the auxiliary power switch Q2 to control the on and off of the auxiliary power switch Q2. The DC-DC controller 40 with the structure has the advantages of simple structure, higher control precision and lower cost.

It will be understood by those skilled in the art that fig. 1 shows a case of having a plurality of DC-DC auxiliary converters 20, and fig. 3 shows a case of having a plurality of DC-DC auxiliary converters 20 and DC-DC controllers 40 corresponding to the plurality of DC-DC auxiliary converters 20 one by one. Fig. 2 and 4 are examples of the structure and connection of one of the DC-DC auxiliary converter 20 and the DC-DC controller 40, and the structures and connection relationships of the other DC-DC auxiliary converter 20 and the DC-DC controller 40 are the same as those shown in fig. 2 and 4.

Specifically, the system comprises n DC-DC auxiliary converters 20 and n corresponding DC-DC controllers 40, which form n total output ports, where n is a positive integer greater than or equal to 2. The main input port of the isolated PFC main converter 10 outputs a main voltage Vo, the auxiliary output ports of the n DC-DC auxiliary converters 20 output n auxiliary voltages Vo21 to Vo2n, respectively, the total voltages of the n total output ports are Vo + Vo21 to Vo + Vo2n, respectively, and the total currents of the n total output ports are Io1 to Ion, respectively. The n total output ports are respectively connected with the n LED lamp strings LED1 to LEDn.

When the main output port and the n auxiliary output ports are connected in series, n filter capacitors Co1 to Con are correspondingly arranged one by one. n filter capacitors Cb1 to Cbn are provided in one-to-one correspondence to the auxiliary input ports of the n DC-DC auxiliary converters 20, and n filter capacitors Co21 to Co2n are provided in one-to-one correspondence to the auxiliary output ports of the n DC-DC auxiliary converters 20. The PFC controller 30 is connected to the n auxiliary output ports in a one-to-one correspondence through n rectifier diodes Ds1 to Dsn. The n DC-DC controllers 40 are respectively connected to n PWM digital dimming signal sources Dim1 to Dimn.

In an alternative embodiment, the isolated PFC main converter 10 comprises a flyback converter or a forward converter; the DC-DC auxiliary converter 20 includes one of a buck converter, a boost converter, a buck-boost converter, a flyback converter, a forward converter, a buck converter, a single-ended primary inductive converter, and a zero-voltage switching converter.

The isolated PFC main converter 10 includes a PFC power conversion unit 11, a rectifier diode D5, a rectifier diode Db, a voltage converter 12, and a main power switching tube Q1. The several units may constitute an isolated PFC main converter 10 of the type buck converter, boost converter and buck-boost converter. The main power switch tube Q1 also has a body diode D_Q1. The main input ports include main input port 1 and main input port 2. The main output port includes a main output port 3 and a main output port 4.

Specifically, referring to fig. 4, the PFC power conversion unit 11 may include an LC filter circuit, a diode full-bridge rectifier circuit, and a filter capacitor Cin. The LC filter circuit comprises a capacitor Cf and an inductor Lf, and two half-bridge circuits of a diode full-bridge rectifying circuit, wherein one half-bridge circuit is formed by connecting diodes D1 and D3 in series, the other half-bridge circuit is formed by connecting diodes D2 and D4 in series, D1 and D2 are located on the upper portion, and D3 and D4 are located on the lower portion. There is a first node between D1 and D3 and a second node between D2 and D4. One end of the inductor Lf is connected with one pole of the alternating current power supply 50 through the main input port 1, and the other end is connected with the first node; one end of the capacitor Cf is connected to the other end of the inductor Lf, and the other end of the capacitor Cf and the second node are both connected to the other pole of the ac power supply 50 through the main input port 2. The filter capacitors Cin and D2 are connected in parallel with the half bridge formed by D4. In addition, the two half bridges and the filter capacitor Cin are connected in parallel and then grounded.

Referring to fig. 4, the following details the structure of the isolated PFC main converter 10 of the flyback converter type:

the first main winding 121, the main power switch Q1 and the resistor Ri are connected in series and then connected in parallel with the filter capacitor Cin. The drain of the main power switch Q1 is connected to the first main winding 121, the source of the main power switch Q1 is connected to the resistor Ri, and the gate of the main power switch Q1 is connected to the Q terminal of the flip-flop U4 via the second main sampling port a 6. A rectifier diode D5 is connected between the first auxiliary winding 122 and the main output port. The second main winding 123 is connected to the first main acquisition port through a resistor Rdem; the rectifier diode Db is connected between the second auxiliary winding 124 and the auxiliary input port 5.

The DC-DC auxiliary converter 20 includes an auxiliary power switch Q2, an inductor L2 (or transformer T2), and a rectifier diode D7. Wherein the auxiliary input ports comprise an auxiliary input port 5 and an auxiliary input port 6. The auxiliary output ports include an auxiliary output port 7 and an auxiliary output port 8. The auxiliary power switch tube Q2 also has a body diode D_Q2。

Referring to fig. 4, the construction of the buck converter type DC-DC auxiliary converter 20 is described in detail below:

the source of the auxiliary power switch Q2 is connected to one end of the inductor L2, the drain is connected to the auxiliary input port 5, and the gate is connected to the output of the second auxiliary comparator U6. The other end of the inductor L2 is connected to the auxiliary output port 7, one end of the rectifier diode D7 is connected between the source of the auxiliary power switch Q2 and one end of the inductor L2, and the other end of the rectifier diode D7 is connected between the auxiliary input port 6 and the auxiliary output port 8.

Referring to fig. 5, the constitution of the boost converter type DC-DC auxiliary converter 20 is described in detail below:

one end of the inductor L2 is connected to the auxiliary input port 5, and the other end is connected to one end of the rectifier diode D7. The other end of the rectifying diode D7 is connected to the auxiliary output port 7. The source of the auxiliary power switch Q2 is connected between the auxiliary input port 6 and the auxiliary output port 8, the drain is connected between the inductor L2 and the rectifier diode D7, and the gate is connected to the output of the second auxiliary comparator U6.

Referring to fig. 6, the following details the structure of the buck-boost converter type DC-DC auxiliary converter 20:

the source of the auxiliary power switch Q2 is connected to the auxiliary output port 8, the drain is connected to the auxiliary input port 5, and the gate is connected to the output of the second auxiliary comparator U6. The rectifier diode D7 is connected between the auxiliary input port 6 and the auxiliary output port 7. One end of the inductor L2 is connected between the source of the auxiliary power switch Q2 and the auxiliary output port 8, and the other end of the inductor L2 is connected between the auxiliary input port 6 and the rectifier diode D7.

Referring to fig. 7, the construction of the negative buck converter type DC-DC auxiliary converter 20 is described in detail below:

the source of the auxiliary power switch Q2 is connected to one end of the inductor L2, the drain is connected to the auxiliary input port 5, and the gate is connected to the output of the second auxiliary comparator U6. The other end of the inductor L2 is connected to the auxiliary output port 7. One end of the rectifier diode is connected between the auxiliary input port 6 and the auxiliary output port 8, and the other end is connected between the source of the auxiliary power switch tube Q2 and one end of the inductor L2.

Referring to fig. 8, the following details the configuration of the flyback converter type DC-DC auxiliary converter 20:

the transformer T2 comprises a first winding and a second winding, wherein one end of the first winding is connected with the auxiliary input port 5, and the other end of the first winding is connected with the drain electrode of the auxiliary power switch tube Q2; the source electrode of the auxiliary power switch tube Q2 is connected with the auxiliary input port 6, and the grid electrode of the auxiliary power switch tube Q2 is connected with the output end of the second auxiliary comparator U6; one end of the second winding of the transformer T2 is connected to the rectifier diode D7, the other end of the rectifier diode D7 is connected to the auxiliary output port 7, and the other end of the second winding is connected to the auxiliary output port 8.

In addition, the circuit is also provided with filter capacitors Co1, Cb and Co2, wherein the filter capacitor Co1 is connected between the

main input ports

3 and 4 for filtering the output voltage of the main input ports. The filter capacitor Cb is connected between the

auxiliary input ports

5 and 6, and filters the input voltage at the auxiliary input ports. The filter capacitor Co2 is connected between the

auxiliary output ports

7 and 8 to filter the output voltage at the auxiliary output ports.

Embodiments of the present application also provide an LED lighting device including the wide voltage isolation AC-DC multi-channel driver provided in any of the alternative embodiments of the present application.

The embodiments of the present application have been described in detail, and specific embodiments thereof have been presented in the context of illustrating the principles and implementations of the present application.

Claims

1. A wide voltage isolation AC-DC multichannel driver, comprising: isolating the PFC main converter and the plurality of DC-DC auxiliary converters;

the isolated PFC main converter comprises a PFC power conversion unit, a voltage converter and a main output port, wherein the voltage converter comprises a first main winding, a second main winding, a first auxiliary winding and a second auxiliary winding; the first main winding and the first auxiliary winding are mutually induced, and the second main winding and the second auxiliary winding are mutually induced; the DC-DC auxiliary converter comprises an auxiliary input port and an auxiliary output port;

the output end of the PFC power conversion unit is connected with the first main winding; the first auxiliary winding is connected with the main output port; the second auxiliary windings are respectively connected with the auxiliary input ports of the plurality of DC-DC auxiliary converters; the auxiliary output ports of the plurality of DC-DC auxiliary converters are respectively connected with the main output port in series to form a plurality of total output ports;

the PFC power conversion unit converts the received alternating current into direct current and outputs the direct current to the voltage converter; after receiving the direct current, the voltage converter converts a main voltage through the first main winding and the first auxiliary winding, outputs the main voltage to the main output port, and the main output port transmits the main voltage to the main output port; converting an auxiliary voltage through the second main winding and the second auxiliary winding, and outputting the auxiliary voltage to the auxiliary input ports of the plurality of DC-DC auxiliary converters respectively; the DC-DC auxiliary converter receives the auxiliary voltage from the auxiliary input port, processes the auxiliary voltage and outputs the auxiliary voltage to the auxiliary output port, the auxiliary output port transmits the auxiliary voltage to the main output port, and the main output port receives the main voltage and the auxiliary voltage and outputs the main voltage.

2. The wide voltage isolation AC-DC multichannel driver of claim 1, wherein the wide voltage isolation AC-DC multichannel driver further comprises: a PFC controller; the isolated PFC main converter further includes: a main power switch tube;

the main power switch tube is connected with the first main winding;

the PFC controller comprises a main feedback port, a first main acquisition port, a main control port, a main reference voltage port and a main reference sawtooth wave signal port; the main feedback port is connected with the auxiliary output port, the first main acquisition port is connected with the second main winding, and the main control port is connected with the control end of the main power switch tube;

the auxiliary output port transmits the auxiliary voltage to the main feedback port, and the PFC controller receives the auxiliary voltage from the main feedback port, the voltage of the second main winding from the first main acquisition port, the main reference voltage from the main reference voltage port, and a main reference sawtooth signal from the main reference sawtooth signal port; comparing the auxiliary voltage with the main reference voltage to form a voltage error signal; comparing the voltage error signal with the main reference sawtooth wave signal to form a stop pulse signal; forming a start pulse signal based on a voltage of the second main winding; and controlling the on and off of the main power switch tube by using the stop pulse signal and the start pulse signal.

3. The wide voltage isolation AC-DC multi-channel driver of claim 2, wherein the PFC controller further comprises a second primary acquisition port; the second main acquisition port is connected with the main power switch tube;

the PFC controller also receives the voltage of the main power switch tube from the second main acquisition port;

the comparing the voltage error signal and the main reference sawtooth wave signal to form a stop pulse signal includes: and comparing the voltage error signal with the voltage of the main power switch tube to form a comparison result, and comparing the main reference sawtooth wave signal with the comparison result to form a stop pulse signal.

4. The wide voltage isolation AC-DC multichannel driver of claim 3, wherein the PFC controller includes a master reference voltage source, a master reference sawtooth signal source, a first master comparator, a second master comparator, a third master comparator, and a flip-flop; the flip-flop is provided with an S port, a Q port and an R port;

a negative input terminal of the first master comparator is connected to the master feedback port, a positive input terminal of the first master comparator is connected to the master reference voltage source through the master reference voltage port, and an output terminal of the first master comparator is connected to a positive input terminal of the second master comparator; the negative input end of the second main comparator is connected with the second main acquisition port, and the output end of the second main comparator is connected with the positive input end of the third main comparator; the negative input end of the third main comparator is connected with the main reference sawtooth wave signal source through the main reference sawtooth wave signal port, and the output end of the third main comparator is connected with the R port; the Q port is connected with the main control port, and the S port is connected with the first main acquisition port;

the first master comparator is to: comparing the auxiliary voltage with the main reference voltage to form a voltage error signal; the second master comparator is to: comparing the voltage error signal with the voltage of the main power switch tube to form a comparison result; the third master comparator is to: comparing the main reference sawtooth wave signal with the comparison result to form a stop pulse signal; the trigger is used for: forming a start pulse signal based on a voltage of the second main winding; and controlling the on and off of the main power switch tube by using the stop pulse signal and the start pulse signal.

5. The wide voltage isolation AC-DC multichannel driver of claim 1, wherein the wide voltage isolation AC-DC multichannel driver further comprises: a DC-DC controller; the DC-DC auxiliary converter further includes: an auxiliary power switch tube;

the DC-DC controller comprises an auxiliary feedback port, an auxiliary control port, an auxiliary reference current port and an auxiliary reference sawtooth wave signal port; the auxiliary feedback port is connected with the auxiliary output port, and the auxiliary control port is connected with the control end of the auxiliary power switch tube;

the total output port receives the main voltage and the auxiliary voltage and then outputs total current; the total current is transmitted to the secondary feedback port; after the DC-DC controller receives the total current from the auxiliary feedback port, the auxiliary reference current from the auxiliary reference current port and the auxiliary reference sawtooth wave signal from the auxiliary reference sawtooth wave signal port, comparing the total current with the auxiliary reference current to form a voltage error signal; and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal, and transmitting the control signal to the control end of the auxiliary power switch tube.

6. The wide voltage isolation AC-DC multichannel driver according to claim 5, wherein the DC-DC controller further comprises: a PWM digital dimming signal port;

the DC-DC controller also receives a PWM digital dimming signal from the PWM digital dimming signal port;

the comparing the voltage error signal and the auxiliary reference sawtooth wave signal to form a control signal comprises: and comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal, and forming a control signal based on the comparison signal and the PWM digital dimming signal.

7. The wide voltage isolation AC-DC multichannel driver according to claim 6, characterized in that the DC-DC controller comprises: the circuit comprises a first auxiliary comparator, a second auxiliary comparator, an AND gate circuit, an auxiliary reference current source, an auxiliary reference sawtooth wave signal source and a PWM digital dimming signal source;

the negative input end of the first auxiliary comparator is connected with the auxiliary feedback port, the positive input end of the first auxiliary comparator is connected with the auxiliary reference current source through the auxiliary reference current port, and the output end of the first auxiliary comparator is connected with the positive input end of the second auxiliary comparator; the negative input end of the second auxiliary comparator is connected with the auxiliary reference sawtooth wave signal source through the auxiliary reference sawtooth wave signal port, the output end of the second auxiliary comparator is connected with one input end of the AND gate circuit, and the other input end of the AND gate circuit is connected with the PWM digital dimming signal source through the PWM digital dimming signal port; the output end of the AND gate circuit is connected with the auxiliary control port;

the first auxiliary comparator is to: comparing the total current with the auxiliary reference current to form a voltage error signal; comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a control signal; the second auxiliary comparator is to: comparing the voltage error signal with the auxiliary reference sawtooth wave signal to form a comparison signal; the AND gate circuit is used for: and performing AND calculation on the comparison signal and the PWM digital dimming signal to form a control signal, and transmitting the control signal to a control end of the auxiliary power switch tube.

8. The wide voltage isolation AC-DC multichannel driver according to any of claims 1 to 7, characterized in that the isolation PFC main converter comprises a flyback converter or a forward converter.

9. The wide voltage isolation AC-DC multichannel driver according to any of claims 1 to 7, wherein the DC-DC auxiliary converter comprises one of a buck converter, a boost converter, a buck-boost converter, a flyback converter, a forward converter, a Cuk converter, a single ended primary inductive converter, and a zero voltage switching converter.

10. An LED lighting device comprising the wide voltage isolation AC-DC multi-channel driver of any one of claims 1 to 9.