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CN-116528426-B - Soft-switch multipath dimmable LED driver and driving method thereof

CN116528426BCN 116528426 BCN116528426 BCN 116528426BCN-116528426-B

Abstract

The invention discloses a soft-switching multipath dimmable LED driver, which comprises a direct-current power supply V in , a switching tube S 1 , a switching tube S 2 , a resonant capacitor C r1 , a resonant capacitor C r2 , a common inductor L s , a first full-wave rectification double-path current-sharing unit and a second full-wave rectification double-path current-sharing unit. The invention also discloses a soft switch multipath dimmable LED driving method, which adopts a common inductor as the resonant inductance of the two resonant cavities, and has no transformer, reduced number of magnetic elements and improved power density. The switching tube can realize zero-voltage switching, so that the switching loss is greatly reduced, and the efficiency is high. Four paths of current output can be realized, and dimming is realized by two paths as a group, so that the LED lamp is suitable for occasions of multicolor lighting application.

Inventors

  • ZHANG JIE
  • Xie Weichong
  • JIANG LU
  • WU YUHENG
  • ZHOU WEI
  • CHEN YIFEI
  • SHEN SHIJIE

Assignees

  • 湖北工业大学

Dates

Publication Date
20260512
Application Date
20230518

Claims (9)

  1. 1. A soft-switching multipath dimmable LED driver comprises a direct-current power supply V in and is characterized by further comprising a switching tube S 1 , a switching tube S 2 , a resonant capacitor C r1 , Resonant capacitor C r2 , common inductance L s , The positive electrode of the direct current input power supply V in is respectively connected with the drain electrode of the switch tube S 1 and the positive electrode of the resonant capacitor C r1 , the negative electrode of the resonant capacitor C r1 is connected with the positive electrode interface of the first full-wave rectification double-circuit current equalizing unit, the source electrode of the switch tube S 1 and the drain electrode of the switch tube S 2 are both connected with the positive electrode of the common inductor L s , the negative electrode of the common inductor L s is respectively connected with the negative electrode interface of the first full-wave rectification double-circuit current equalizing unit and the positive electrode interface of the second full-wave rectification double-circuit current equalizing unit, the source electrode of the switch tube S 2 is respectively connected with the negative electrode of the direct current input power supply V in and the negative electrode of the resonant capacitor C r2 , and the positive electrode of the resonant capacitor C r2 is connected with the negative electrode interface of the second full-wave rectification double-circuit current equalizing unit.
  2. 2. The soft-switching multi-path dimmable LED driver of claim 1, wherein said first full-wave rectified two-path current sharing unit comprises a freewheeling diode D 1 , a freewheeling diode D 2 , a freewheeling diode D 3 , a freewheeling diode D 4 , a filter capacitance C o1 , a filter capacitance C o2 , an output load LED 1 , and an output load LED 2 , The positive electrode interface of the first full-wave rectification double-path current equalizing unit is respectively connected with the cathode of a freewheeling diode D 1 and the anode of a freewheeling diode D 2 , the cathode of a freewheeling diode D 2 is connected with the anode of an output load LED 1 , the cathode of an output load LED 1 , the anode of a freewheeling diode D 4 and the cathode of an output load LED 2 are respectively connected with the anode of a freewheeling diode D 1 , the anode of an output load LED 2 is connected with the cathode of the freewheeling diode D 3 , the anode of a freewheeling diode D 3 and the cathode of the freewheeling diode D 4 are respectively connected with the negative electrode interface of the first full-wave rectification double-path current equalizing unit, the anode and the cathode of an output load LED 1 are connected with a filter capacitance C o1 in parallel, and the anode and the cathode of the output load LED 2 are connected with the filter capacitance C o2 in parallel.
  3. 3. The soft-switching multi-path dimmable LED driver of claim 2, wherein said second full-wave rectified two-path current sharing unit comprises a freewheeling diode D 5 , a freewheeling diode D 6 , a freewheeling diode D 7 , a freewheeling diode D 8 , a filter capacitance C o3 , a filter capacitance C o4 , an output load LED 3 , and an output load LED 4 , The negative electrode interface of the second full-wave rectification double-path current sharing unit is respectively connected with the cathode of a freewheeling diode D 7 and the anode of a freewheeling diode D 8 , the cathode of a freewheeling diode D 8 is connected with the anode of an output load LED 4 , the cathode of an output load LED 4 , the anode of a freewheeling diode D 7 and the cathode of an output load LED 3 are respectively connected with the anode of a freewheeling diode D 6 , the anode of an output load LED 3 is connected with the cathode of the freewheeling diode D 5 , the anode of a freewheeling diode D 5 and the cathode of the freewheeling diode D 6 are respectively connected with the positive electrode interface of the second full-wave rectification double-path current sharing unit, the anode and the cathode of an output load LED 3 are connected with a filter capacitance value C o3 in parallel, and the anode and the cathode of the output load LED 4 are connected with the filter capacitance value C o4 in parallel.
  4. 4. A method of driving a soft-switching multi-channel dimmable LED using a soft-switching multi-channel dimmable LED driver according to claim 3, comprising the following modes in one switching cycle: Mode 1, the starting and ending moments of mode 1 are t 0 and t 1 , when the switch tube S 1 is turned on, mode 1 starts from time t 0 , the switch tube S 2 is turned off, the drain-source voltage of the switch tube S 2 is the input power V in , the instantaneous current I Ls of the common inductor Ls is linearly increased by bearing the forward voltage, and freewheels through the body diode of the switch tube S 1 , so that the drain-source voltage of the switch tube S 1 is zero, zero voltage turn-on is provided for the switch tube S 1 , the resonance current I cr1 on the resonance capacitor C r1 and the resonance current I cr2 on the resonance capacitor C r2 resonate to zero, the freewheel diode D 2 、D 4 、D 6 , And D 8 is on, freewheeling diodes D 1 、D 3 、D 5 , and D 7 achieve zero current turn-off, entering mode 2 when the instantaneous current i Ls of common inductor L s rises to 0.
  5. 5. The method of driving a soft-switching multi-channel dimmable LED of claim 4, further comprising the following modes: Mode 2, the beginning and ending times of mode 2 are t 1 and t 2 ,i Ls 、i cr1 , respectively, and i cr2 are defined as the common inductance L s , a resonant capacitor C r1 , And the instantaneous current flowing through the resonant capacitor C r2 , when i Ls =0,i Cr1 =0,i Cr2 =0, the mode 2 starts at time t 1 , the drain-source voltage of the switching tube S 2 is the input power V in , the instantaneous current i Ls of the common inductor L s linearly rises, the resonant capacitor C r2 starts to be charged, the resonant capacitor C r1 slowly discharges the input power V in , the freewheeling diodes D 5 and D 7 are turned on, and the freewheeling diode D 1 、D 2 、D 3 、D 4 、D 6 , And D 8 reverse cut-off, into modality 3.
  6. 6. The method of driving a soft-switching multi-channel dimmable LED of claim 5, further comprising the following modes: Mode 3, the starting and ending times of mode 3 are t 2 and t 3 , at time t 2 , the instantaneous current i Ls of the common inductor L s rises to a peak value, the instantaneous current i Ls of the common inductor L s slowly charges the parasitic capacitance and resonant capacitance C r2 of the switching tube S 1 before the switching tube S 2 is turned on, the instantaneous current i Ls of the common inductor L s begins to discharge the parasitic capacitance and resonant capacitance C r1 of the switching tube S 2 , the freewheeling diode D 1 、D 3 、D 5 , And D 7 is turned on, the freewheeling diode D 2 、D 4 、D 6 and D 8 are turned off in reverse, and when the drain-source voltage of the switching tube S 2 drops to zero, the body diode of the switching tube S 2 is turned on and enters mode 4.
  7. 7. The method of driving a soft-switching multi-channel dimmable LED of claim 6, further comprising the following modes: Modality 4, the starting and ending moments of modality 4 are t 3 and t 4 , when the switching tube S 2 is turned on, modality 4 starts from time t 3 , the instantaneous current I Ls of the common inductor L s is subjected to reverse voltage and linearly drops, and freewheels through the body diode of the switching tube S 2 , so that the drain-source voltage of the switching tube S 2 is zero, zero voltage on is provided for the switching tube S 2 , the resonant current I cr1 on the resonant capacitor C r1 and the resonant current I cr2 on the resonant capacitor C r2 resonate to zero, the freewheeling diode D 1 、D 3 、D 5 and D 7 are turned on, the freewheeling diode D 2 、D 4 、D 6 and D 8 realize zero current off, and modality 5 is entered.
  8. 8. The method of driving a soft-switching multi-channel dimmable LED of claim 7, further comprising the following modes: Mode 5, the starting and ending moments of mode 5 are t 4 and t 5 , when the instantaneous current i Ls =0,i Cr1 =0,i Cr2 =0 of the common inductor L s , mode 5 starts at time t 4 , the drain-source voltage of the switch tube S 1 is the input power V in , the instantaneous current i Ls of the common inductor L s is negative after time t 3 , the resonance capacitor C r2 is linearly reduced to charge the common inductor L s , the input power V in is slowly charging the resonance capacitor C r1 , the freewheeling diodes D 6 and D 8 are turned on, the freewheeling diode D 1 、D 2 、D 3 、D 4 、D 5 is, And D 7 is turned off in the reverse direction, and mode 5 ends when the instantaneous current i Ls of the common inductance L s drops to 0.
  9. 9. The method of driving a soft-switching multi-channel dimmable LED of claim 8, further comprising the following modes: Mode 6, with start and end times of mode 6 being t 5 and t 6 , and before switching tube S 1 is turned on at time t 6 , instantaneous current i Ls of common inductor L s continues to decrease linearly until peak value, instantaneous current iL s of common inductor L s charges parasitic capacitance and resonance capacitance C r1 of switching tube S 2 , instantaneous current iL s of common inductor L s charges parasitic capacitance of switching tube S 1 , instantaneous current iL s of common inductor L s discharges resonance capacitance C r2 , freewheeling diode D 2 、D 4 、D 6 , And D 8 is turned on, freewheeling diode D 1 、D 3 、D 5 , and D 7 are turned off in reverse, and when the drain-source voltage of switching tube S 1 drops to zero, the body diode of switching tube S 1 is turned on, reentering the next switching cycle.

Description

Soft-switch multipath dimmable LED driver and driving method thereof Technical Field The invention relates to the field of LED driving control, in particular to a soft-switch multipath dimmable LED driver, and also relates to a soft-switch multipath dimmable LED driving method which is suitable for the fields of power electronics and the like. Background With the development of society, the energy saving efficiency of lighting products becomes critical, and Light Emitting Diodes (LEDs) are widely used in the fields of LCD backlight, housing, industry, signals, etc. due to the advantages of long life, high light efficiency, various colors, etc. However, dimmable multi-output LED drivers are somewhat capable of driving loads of the same voltage and current in multicolor lighting systems, color mixing applications, etc. Some, while achieving independent dimming, increase the converter volume and device count, and the switch is also a hard switch. The LLC resonant converter is applied to LED multicolor illumination, and has the characteristics of soft switching and high efficiency, but the dimming range is influenced by the transformation ratio of the transformer due to the existence of the transformer. Disclosure of Invention The invention aims to solve the problems in the prior art, and provides a soft-switching multi-channel dimmable LED driver and a soft-switching multi-channel dimmable LED driving method. The invention can realize four-way current output by only two switching tubes, a common inductor, two resonant capacitors and eight diodes, wherein the current of the output load LED 1 and the current of the output load LED 2 are uniform, the current of the output load LED 3 and the current of the output load LED 4 are uniform, the output load LED 1 and the output load LED 2 are used as one-way dimming, and the output load LED 3 and the output load LED 4 are used as the other-way dimming. Meanwhile, zero voltage on of all switching tubes and zero current off of diodes can be realized. The above object of the present invention is achieved by the following technical means: A soft switching multipath dimmable LED driver comprises a direct current power supply V in, a switching tube S 1, a switching tube S 2, a resonant capacitor C r1, Resonant capacitor C r2, common inductance L s, The positive electrode of the direct current input power supply V in is respectively connected with the drain electrode of the switch tube S 1 and the positive electrode of the resonant capacitor C r1, the negative electrode of the resonant capacitor C r1 is connected with the positive electrode interface of the first full-wave rectification double-circuit current equalizing unit, the source electrode of the switch tube S 1 and the drain electrode of the switch tube S 2 are both connected with the positive electrode of the common inductor L s, the negative electrode of the common inductor L s is respectively connected with the negative electrode interface of the first full-wave rectification double-circuit current equalizing unit and the positive electrode interface of the second full-wave rectification double-circuit current equalizing unit, the source electrode of the switch tube S 2 is respectively connected with the negative electrode of the direct current input power supply V in and the negative electrode of the resonant capacitor C r2, and the positive electrode of the resonant capacitor C r2 is connected with the negative electrode interfaces of the two full-wave rectification double-circuit current equalizing units. The first full-wave rectification two-way current sharing unit includes a freewheeling diode D 1, a freewheeling diode D 2, a freewheeling diode D 3, a freewheeling diode D 4, a filter capacitance value C o1, a filter capacitance value C o2, an output load LED 1, and an output load LED 2 as described above, The positive electrode interface of the first full-wave rectification double-path current equalizing unit is respectively connected with the cathode of a freewheeling diode D 1 and the anode of a freewheeling diode D 2, the cathode of a freewheeling diode D 2 is connected with the anode of an output load LED 1, the cathode of an output load LED 1, the anode of a freewheeling diode D 4 and the cathode of an output load LED 2 are respectively connected with the anode of a freewheeling diode D 1, the anode of an output load LED 2 is connected with the cathode of the freewheeling diode D 3, the anode of a freewheeling diode D 3 and the cathode of the freewheeling diode D 4 are respectively connected with the negative electrode interface of the first full-wave rectification double-path current equalizing unit, the anode and the cathode of an output load LED 1 are connected with a filter capacitance C o1 in parallel, and the anode and the cathode of the output load LED 2 are connected with the filter capacitance C o2 in parallel. The second full-wave rectification two-way current sharing unit includes a freewh