CN114598159B - Compensation method and circuit for synchronous rectifier tube turn-on delay - Google Patents

Compensation method and circuit for synchronous rectifier tube turn-on delay Download PDF

Info

Publication number
CN114598159B
CN114598159B CN202210242688.9A CN202210242688A CN114598159B CN 114598159 B CN114598159 B CN 114598159B CN 202210242688 A CN202210242688 A CN 202210242688A CN 114598159 B CN114598159 B CN 114598159B
Authority
CN
China
Prior art keywords
compensation
tube
synchronous
voltage
turn
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202210242688.9A
Other languages
Chinese (zh)
Other versions
CN114598159A (en
Inventor
陆杨军
徐大林
朱守伟
王廷营
牟恬恬
王亚洲
曹赟
刘华吾
唐海瑞
杨静
汤晖斌
徐一民
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Shanghai Jieruizhao New Information Technology Co ltd
Original Assignee
Shanghai Jieruizhao New Information Technology Co ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Shanghai Jieruizhao New Information Technology Co ltd filed Critical Shanghai Jieruizhao New Information Technology Co ltd
Priority to CN202210242688.9A priority Critical patent/CN114598159B/en
Publication of CN114598159A publication Critical patent/CN114598159A/en
Application granted granted Critical
Publication of CN114598159B publication Critical patent/CN114598159B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M3/00—Conversion of dc power input into dc power output
    • H02M3/22—Conversion of dc power input into dc power output with intermediate conversion into ac
    • H02M3/24—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters
    • H02M3/28—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac
    • H02M3/325—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal
    • H02M3/335—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only
    • H02M3/33569—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements
    • H02M3/33576—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer
    • H02M3/33592—Conversion of dc power input into dc power output with intermediate conversion into ac by static converters using discharge tubes with control electrode or semiconductor devices with control electrode to produce the intermediate ac using devices of a triode or a transistor type requiring continuous application of a control signal using semiconductor devices only having several active switching elements having at least one active switching element at the secondary side of an isolation transformer having a synchronous rectifier circuit or a synchronous freewheeling circuit at the secondary side of an isolation transformer
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02M—APPARATUS FOR CONVERSION BETWEEN AC AND AC, BETWEEN AC AND DC, OR BETWEEN DC AND DC, AND FOR USE WITH MAINS OR SIMILAR POWER SUPPLY SYSTEMS; CONVERSION OF DC OR AC INPUT POWER INTO SURGE OUTPUT POWER; CONTROL OR REGULATION THEREOF
    • H02M1/00—Details of apparatus for conversion
    • H02M1/42—Circuits or arrangements for compensating for or adjusting power factor in converters or inverters
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02B—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO BUILDINGS, e.g. HOUSING, HOUSE APPLIANCES OR RELATED END-USER APPLICATIONS
    • Y02B70/00—Technologies for an efficient end-user side electric power management and consumption
    • Y02B70/10—Technologies improving the efficiency by using switched-mode power supplies [SMPS], i.e. efficient power electronics conversion e.g. power factor correction or reduction of losses in power supplies or efficient standby modes

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Dc-Dc Converters (AREA)
  • Rectifiers (AREA)

Abstract

The invention discloses a compensation method and a circuit for the turn-on delay of a synchronous rectifying tube, wherein the compensation method generates a turn-on enabling signal by detecting the voltage falling edge of a drain electrode and a source electrode before the synchronous rectifying tube is turned on, and compared with the conventional method for detecting the voltage amplitude of the drain electrode and the source electrode, the turn-on delay of the synchronous rectifying tube, namely the turn-on time of a precursor diode, is reduced, the turn-on loss is reduced, and the converter efficiency is improved. The compensation method and the compensation circuit provided by the invention are simple to realize, do not need signal isolation transmission, are beneficial to improving the power density of the converter, and are particularly suitable for power conversion occasions requiring high frequency and high efficiency.

Description

Compensation method and circuit for synchronous rectifier tube turn-on delay
Technical Field
The invention belongs to the technical field of power electronic conversion, and particularly relates to a compensation method and circuit for synchronous rectifier tube turn-on delay.
Background
The dual clamp zero voltage converter shown in fig. 1 (a) can realize buck-boost power conversion, andcompared with a single-step-up circuit or a single-step-down circuit, the single-step-up circuit can achieve higher conversion efficiency in a wide voltage range, and has a simple circuit structure, so that the single-step-up circuit is widely applied to the power supply fields of new energy power generation, communication, military industry and the like. As shown in fig. 1 (a), the dual-clamp zero-voltage converter is composed of first to fourth primary side switching transistors S P1 ～S P4 First power transformer T 1 (the excitation inductance is the first excitation inductance L m1 ) First clamp capacitor C L1 First synchronous rectifying tube S R1 And a first output filter capacitor C o1 Composition is prepared. Exemplary converter operation waveforms as shown in fig. 1 (b), the converter has three main operation phases in one switching cycle, including an input energy storage phase, a power transfer phase, and a current clamp phase. During the input energy storage phase (t 0 ～t 1 ) First and fourth primary side switching tubes (S P1 And S is P4 ) Conducting, input voltage V in1 Applied to a first power transformer T 1 Primary side of (1), first excitation inductance current i Lm1 Linearly rise with a slope of V in1 /L m1 ；t 1 At the moment, the first and fourth primary side switching tubes (S P1 And S is P4 ) Turn-off, end of input energy storage phase, after which the second and third primary side switching tubes (S P2 And S is P3 ) First synchronous rectifying tube S R1 On, the converter enters the power transfer phase (t 1 ～t 2 ) First excitation inductance L m1 Transferring energy to the load, a first clamping capacitor C L1 Absorbing the first transformer T 1 Primary side leakage inductance energy, avoiding voltage spike, first excitation inductance current i Lm1 Linear decrease with slope of-V C1 /L m1 And has V C1 /n＝V o1 Wherein n is the first power transformer T 1 The ratio of the number of primary turns to the number of secondary turns; t is t 2 Time third primary side switch tube S P3 And a first synchronous rectifying tube S R1 Turn-off, end the power transfer phase, and then fourth primary side switching tube S P4 On, the converter enters the current clamping stage (t 2 ～t 3 ) The voltage at the two ends of the primary side of the transformer is zero, and the first exciting inductance current i Lm1 Remain unchanged.
From the above analysis, the working principle of the dual-clamp zero-voltage converter is similar to that of the flyback converter shown in fig. 2, the synchronous rectifying tubes on the secondary side are all opened at the peak value of exciting inductance current, and the typical working waveform of the secondary side circuit of the converter is shown in fig. 1 (c). As shown in FIG. 3, the synchronous rectification driver judges zero voltage on and zero current off by detecting the amplitude of the voltage across the drain and source of the synchronous rectification tube to generate a driving control signal of the synchronous rectification tube, i.e. when the drain and source voltage is lower than the turn-off threshold voltage V th_on When the drain-source voltage is higher than the turn-off threshold voltage V, the synchronous rectifier is turned on th_off And when the synchronous rectifying tube is turned off. Because of the transmission delay of the internal circuit of the synchronous rectification driver, a certain body diode conduction time exists before the channel of the synchronous rectification tube is conducted, namely, the turn-on delay exists. Because the conduction voltage drop of the body diode is far greater than that of the channel of the switching tube, the larger the switching delay of the synchronous rectifying tube is, namely the longer the switching time of the precursor diode is switched on, the larger the conduction loss is, and the lower the converter efficiency is. The literature "d.fu, etc. a Novel Driving Scheme for Synchronous Rectifiers in LLC Resonant converters.ieee trans.on Power electronic, vol.24, no.5, pp.1321-1329, may, 2009" proposes a compensation method, which uses the primary side control signal of the converter to synchronize the on enable signal of the synchronous rectifier to reduce the on delay, but the compensation method needs a signal isolation circuit, and the signal isolation circuit is required to be disabled after the synchronous rectifier is turned on, so as to avoid affecting the turn-off time of the synchronous rectifier, and the compensation circuit is complex to implement and can reduce the Power density of the converter. On the other hand, the circuit topology suitable for the method has certain limitation, other control signals of the converter are relied on, and for the flyback converter, the turn-on time of the secondary synchronous rectifying tube is after the turn-off time of the primary main switching tube, so that the control signals of the primary main switching tube are required to be inverted and then used for turning-on enabling signals of the synchronous secondary synchronous rectifying tube, and certain transmission delay is brought to a negating circuit and a signal isolation transmission circuit, so that the compensation effect is influenced.
Disclosure of Invention
The invention aims to solve the problems in the prior art and provide a compensation method and a circuit for the turn-on delay of a synchronous rectifying tube.
The technical solution for realizing the purpose of the invention is as follows: a compensation method for the turn-on delay of synchronous rectifier tube features that the voltage drop edge of drain-source electrode before turning on the synchronous rectifier tube is detected to generate turn-on enable signal.
The compensating circuit comprises a first compensating capacitor, a first compensating resistor and a second compensating resistor, wherein the first compensating capacitor and the second compensating resistor are connected in parallel, one end of the first compensating capacitor is connected with the drain electrode of the synchronous rectifying tube, the other end of the first compensating capacitor is connected with the drain-source voltage detection pin of the synchronous rectifying driver and one end of the first compensating resistor, and the other end of the first compensating resistor is connected with the source electrode of the synchronous rectifying tube.
Further, the compensation circuit further comprises a first compensation switch tube, the first compensation switch tube is connected with the first compensation capacitor and the second compensation resistor in parallel, one end of the first compensation switch tube is connected with the drain electrode of the synchronous rectifying tube, and the other end of the first compensation switch tube is connected with the drain-source voltage detection pin of the synchronous rectifying driver and one end of the first compensation resistor.
Further, the compensation circuit further comprises a second compensation switch tube, and the other end of the first compensation resistor is connected with the source electrode of the synchronous rectifying tube through the second compensation switch tube.
Further, the control circuit of the compensation circuit comprises a first NOT gate, which is provided with a signal input end and two signal output ends, wherein the signal input end is connected with the output pin of the synchronous rectification driver, and the two signal output ends respectively output the control signals v of the first compensation switch tube and the second compensation switch tube GSf1 And v GSf2 The method comprises the steps of carrying out a first treatment on the surface of the The voltage signal of the output pin of the synchronous rectification driver is directly used for controlling the opening and closing of the first compensation switching tube, and the voltage signal is used for controlling the opening and closing of the second compensation switching tube after being inverted by the first NOT gate, namely when the synchronous rectifying tube is conducted, the first compensation switching tube is turned on and the second compensation switching tube is turned off, and when the synchronous rectifying tube is turned off, the first compensation switching tube is turned off and the first compensation switching tube is turned onAnd two compensating switching tubes.
Compared with the prior art, the invention has the remarkable advantages that:
1) The compensation method generates an opening enabling signal by detecting the drain-source voltage falling edge before the synchronous rectifier tube is opened, and compared with the conventional method for detecting the drain-source voltage amplitude, the method can reduce the opening delay of the synchronous rectifier tube, namely the opening time of the precursor diode, reduce the conduction loss and improve the efficiency of the converter.
2) The compensation method and the compensation circuit are simple to realize, do not need signal isolation transmission, are beneficial to improving the power density of the converter, and are particularly suitable for power conversion occasions requiring high frequency and high efficiency.
3) The method has strong universality and can be suitable for various converter topologies without depending on other control signals of the converter.
The invention is described in further detail below with reference to the accompanying drawings.
Drawings
Fig. 1 is a schematic circuit diagram and an operational waveform diagram of a dual clamp zero voltage converter.
Fig. 2 is a schematic circuit diagram of a flyback converter.
Fig. 3 is a schematic diagram of the internal circuit structure of a conventional synchronous rectification driver.
Fig. 4 (a) is a schematic circuit diagram of a first implementation of the synchronous rectifier turn-on delay compensation circuit in one embodiment.
Fig. 4 (b) is a schematic circuit diagram of a second implementation of the synchronous rectifier turn-on delay compensation circuit in one embodiment.
Fig. 4 (c) is a schematic circuit diagram of a third implementation of the synchronous rectifier turn-on delay compensation circuit in one embodiment.
Fig. 5 is a schematic diagram of a control circuit of a second implementation and a third implementation of the synchronous rectifier turn-on delay compensation circuit in one embodiment.
Fig. 6 is a waveform diagram of key points of the synchronous rectifier turn-on delay compensation circuit in one embodiment.
FIG. 7 is a waveform diagram of an embodiment of the present invention, wherein FIG. (a) is a first synchronous rectification without compensationTube S R1 Is the first synchronous rectifying tube S after compensation R1 Is delayed by the turn-on time of (2).
FIG. 8 is a graph of experimental efficiency versus the present invention in one embodiment.
Symbol names in the above figures: v (V) in1 And V in2 S is the input voltage of the converter P1 ～S P5 Is a first to fifth primary side switch tube, C L1 For the first clamp capacitance, V C1 For the first clamp capacitor C L1 Voltage at two ends T 1 And T 2 For the first and second power transformers, L m1 And L m2 S is the first and second excitation inductance R1 And S is R2 For the first and second synchronous rectifying tubes, C o1 And C o2 For the first and second output filter capacitors, V o1 And V o2 V is the output voltage of the converter GSP1 ～v GSP4 Is a first to fourth primary side switching tube (S P1 ～S P4 ) Drive control signal i Lm1 For flowing through the first exciting inductance L m1 Current t of (2) 0 ～t 3 For time, i SR1 For flowing into the first synchronous rectifying tube S R1 Current of source, v DSR1 For the first synchronous rectifying tube S R1 Voltage across drain and source of (V) th_on And V th_off V for switching on and off threshold voltages of synchronous rectifying driver GSR1 For the first synchronous rectifying tube S R1 Drive control signal C of (2) f R is the first compensation capacitance f1 And R is f2 For the first and second compensation resistances S f1 And S is f2 For the first and second compensation switch tubes, CS is the drain-source voltage detection pin of the synchronous rectification driver, OUT is the output pin of the synchronous rectification driver, N 1 Is a first NOT gate v GSf1 And v GSf2 For the first and second compensating switch tube (S f1 And S is f2 ) Drive control signal v of (a) CS The driver CS pin voltage is rectified synchronously.
Detailed Description
In order to make the objects, technical solutions and advantages of the present application more apparent, the present application will be further described in detail with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the present application.
It should be noted that, if directional indications (such as up, down, left, right, front, and rear … …) are included in the embodiments of the present invention, the directional indications are merely used to explain the relative positional relationship, movement conditions, etc. between the components in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indications are correspondingly changed.
In addition, if there is a description of "first", "second", etc. in the embodiments of the present invention, the description of "first", "second", etc. is for descriptive purposes only and is not to be construed as indicating or implying a relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present invention.
The embodiment discloses a compensation method and a circuit for synchronous rectifier tube turn-on delay, wherein the compensation method generates a turn-on enabling signal by detecting a drain-source voltage falling edge before the synchronous rectifier tube is turned on.
FIG. 4 shows three embodiments of the synchronous rectifier turn-on delay compensation circuit, which, in combination with FIG. 4 (a), includes a first compensation capacitor C f First compensation resistor R f1 And a second compensation resistor R f2 The first compensation capacitor C f And a second compensation resistor R f2 Parallel connection, a first compensation capacitor C f One end of the first compensation resistor is connected with the drain electrode of the synchronous rectifying tube, and the other end is connected with the drain-source voltage detection pin CS of the synchronous rectifying driver and the first compensation resistor R f1 A first compensation resistor R f1 Another of (2)The end is connected with the source electrode of the synchronous rectifying tube;
in combination with fig. 4 (b), or including a first compensation capacitor C f First compensation resistor R f1 A second compensation resistor R f2 And a first compensating switch tube S f1 The first compensating switch tube S f1 And a first compensation capacitor C f Second compensation resistor R f2 Parallel connection, a first compensation switch tube S f1 One end of the first compensation resistor is connected with the drain electrode of the synchronous rectifying tube, and the other end is connected with the drain-source voltage detection pin CS of the synchronous rectifying driver and the first compensation resistor R f1 A first compensation resistor R f1 The other end of the transistor is connected with the source electrode of the synchronous rectifying tube;
in combination with fig. 4 (C), or including a first compensation capacitor C f First compensation resistor R f1 A second compensation resistor R f2 First compensation switch tube S f1 And a second compensating switch tube S f2 The first compensating switch tube S f1 And a first compensation capacitor C f Second compensation resistor R f2 Parallel connection, a first compensation switch tube S f1 One end of the first compensation resistor is connected with the drain electrode of the synchronous rectifying tube, and the other end is connected with the drain-source voltage detection pin CS of the synchronous rectifying driver and the first compensation resistor R f1 A first compensation resistor R f1 The other end of (a) is connected with a second compensation switch tube S f2 One end of the second compensation switch tube S f2 The other end of the transistor is connected with the source electrode of the synchronous rectifying tube.
FIG. 5 shows a schematic diagram of a control circuit for the two embodiments of the circuits of FIGS. 4 (b) and (c) including a first NOT gate N 1 Has a signal input end and two signal output ends, wherein the signal input end is connected with the output pin OUT of the synchronous rectification driver, and the two signal output ends output a first compensation switch tube S f1 And a second compensating switch tube S f2 Control signal v of (2) GSf1 And v GSf2 . As shown in fig. 5, the voltage signal at the output pin OUT of the synchronous rectification driver is directly used for controlling the first compensation switch tube S f1 Is turned on and off by the first NOT gate N 1 After the phase inversion, is used for controlling a second compensation switch tube S f2 Is opened and closed by (2)I.e. when the synchronous rectifier tube is turned on, the first compensating switch tube S is turned on f1 And turn off the second compensation switch S f2 When the synchronous rectifying tube is turned off, the first compensating switch tube S is turned off f1 And turn on the second compensation switch tube S f2 。
Fig. 6 shows the key point operating waveforms for a dual clamp zero voltage converter using the circuit of the embodiment of fig. 4 (a). From the above analysis, the dual-clamp zero-voltage converter has three main operation phases including an input energy storage phase, a power transmission phase and a current clamp phase in one switching cycle. In the input energy storage stage, the first and fourth primary side switching tubes (S P1 And S is P4 ) Conducting, input voltage V in1 Applied to a first power transformer T 1 Primary side of (1) a first synchronous rectifier S R1 Voltage v across drain and source of (2) DSR1 ＝V o1 +V in1 The voltage at the drain-source voltage detection pin CS of the synchronous rectification driver is:
higher than the on threshold voltage V th_on First synchronous rectifying tube S R1 Remain off. First compensation capacitor C f The voltage at two ends is:
first and fourth primary side switching tubes (S P1 And S is P4 ) Turn-off, end of input energy storage phase, after which the second and third primary side switching tubes (S P2 And S is P3 ) On, first clamp capacitor C L1 Voltage V at two ends C1 Applied to a first power transformer T 1 Is the primary side of (c). From the first and fourth primary side switching tubes (S P1 And S is P4 ) Turn off the second and third primary side switching transistors (S P2 And S is P3 ) During the switching-on process, the first power transformer T 1 The voltage at the two ends of the primary side is V in1 Change to-V C1 Due to the first compensation capacitance C f The voltage at two ends cannot be suddenly changed, and the voltage of a drain-source voltage detection pin CS of the synchronous rectification driver is v CS Will be from [ R f1 /(R f1 +R f2 )]×(V o1 +V in1 Change to- [ R/n) f2 /(R f1 +R f2 )]×(V o1 +V in1 N) below the turn-on threshold voltage V th_on First synchronous rectifying tube S R1 On, the converter enters the power transfer phase. And from the above analysis, it can be seen that the voltage v CS Below the turn-on threshold voltage V th_on Is earlier than the voltage v across the drain and source DSR1 Below the turn-on threshold voltage V th_on Therefore, compared with the compensation circuit without the compensation circuit shown in fig. 3, the switching-on time of the synchronous rectifier can be advanced after the compensation circuit is adopted, so that the on time of the body diode is reduced, and the on loss is reduced.
First synchronous rectifying tube S R1 After being conducted, the first compensation capacitor C f Through the first and second compensation resistances (R f1 And R is f2 ) Discharging, synchronous rectification driver drain-source voltage detection pin CS voltage v CS Will be from- [ R f2 /(R f1 +R f2 )]×(V o1 +V in1 N) to [ R ] f1 /(R f1 +R f2 )]×v DS(on) Wherein v is DS(on) For the first synchronous rectifying tube S R1 When v is CS Voltage higher than the turn-off threshold voltage V th_off At the time, the first synchronous rectifying tube S R1 And (5) switching off. It can be seen that the first synchronous rectifier S R1 Is still directly dependent on the relationship between the drain-source voltage and the turn-off threshold voltage due to the first and second compensation resistors (R f1 And R is f2 ) The voltage dividing function of the synchronous rectification driver is that the turn-off time is advanced by a certain time compared with the non-compensation time, but the turn-off threshold voltage of the actual synchronous rectification driver is very close to 0mV, and the current flows through the first synchronous rectification tube S when the synchronous rectification driver is turned off R1 Since the current of (2) is very small, the effect of the advance of the off-time on the on-loss is also very small and negligible.
Third primary side switch tube S P3 And first synchronizationRectifying tube S R1 Turn-off, end the power transfer phase, and then fourth primary side switching tube S P4 The switching on, the converter enters the current clamping stage. Switching tube S from the third primary side P3 Switch-off to fourth primary side switching tube S P4 During the switching-on process, the first power transformer T 1 The voltage at both ends of primary side is from-V C1 Changing to zero due to the first compensation capacitance C f The voltage at two ends will not break, and the voltage of the drain-source voltage detection pin (CS) v of the synchronous rectification driver CS Will be from [ R f1 /(R f1 +R f2 )]×v DS(on) Change to V o1 After that, the first compensation capacitor C f Through the first and second compensation resistances (R f1 And R is f2 ) Charging, v CS Will be from V o1 Change to [ R ] f1 /(R f1 +R f2 )]×V o1 And is always higher than the on threshold voltage V th_on First synchronous rectifying tube S R1 And the device can not be opened by mistake.
Second primary side switching tube S P2 Turning off, ending the current clamping stage, and then the first primary side switching tube S P1 The converter is turned on and enters an input energy storage stage. From the second primary side switch tube S P2 Switch off to the first primary side switch tube S P1 During the switching-on process, the first power transformer T 1 The voltage across the primary side varies from zero to V in1 Due to the first compensation capacitance C f The voltage at two ends cannot be suddenly changed, and the voltage of a drain-source voltage detection pin CS of the synchronous rectification driver is v CS Will be from [ R f1 /(R f1 +R f2 )]×V o1 Change to [ R ] f1 /(R f1 +R f2 )]×V o1 +V in1 N, then a first compensation capacitor C f Through the first and second compensation resistances (R f1 And R is f2 ) Charging, v CS Will be from [ R f1 /(R f1 +R f2 )]×V o1 +V in1 Change of/n to [ R ] f1 /(R f1 +R f2 )]×(V o1 +V in1 N) is always higher than the turn-on threshold voltage V th_on First synchronous rectifying tube S R1 And the device can not be opened by mistake.
FIG. 4 (b) shows an embodimentThe principle of operation of the example circuit is similar to that of the compensation circuit of fig. 4 (a), except that: first synchronous rectification switch tube S R1 After being conducted, the first compensating switch tube S f1 Conducting to the first compensation capacitor C f Fast discharge, then drain-source voltage detection pins CS and S of synchronous rectification driver f1 Is short-circuited at the drain of CS pin voltage v CS ＝v DS(on) Will not cause S R1 Advance of the turn-off time.
The circuit of the embodiment shown in fig. 4 (c) operates in a similar manner to the compensation circuit shown in fig. 4 (b), except that: first synchronous rectification switch tube S R1 After being conducted, the second compensating switch tube S f2 Turn off, so that S R1 During the on period, the first compensation resistor R f1 Not connected in parallel to S R1 Therefore, the first excitation inductance L m1 Is completely passed through S R1 The loss can be further reduced.
From the above analysis, the drain-source voltage detection pin (CS) voltage v of synchronous rectification driver CS Is- [ R ] f2 /(R f1 +R f2 )]×(V o1 +V in1 N) is designed such that the value is greater than V CS_min To ensure that the synchronous rectification drive is not damaged, wherein V CS_min The maximum negative voltage value allowed to be applied to the CS pin of the synchronous rectification driver. Thus the first and second compensation resistances (R f1 And R is f2 ) The following relationship needs to be satisfied:
v in the above o1 +V in1 N is the first synchronous rectifying tube S of the dual-clamping zero-voltage converter R1 Switching on the voltage v at the two ends of the front drain and the source DSR1 More generally, the voltage conversion amount of (2)
Wherein DeltaV PK For the first synchronous rectifying tube S R1 Switching on the voltage v at the two ends of the front drain and the source DSR1 Voltage conversion amount of (a) is set.
Further, as can be seen from the above analysis, in the first and fourth primary side switching tubes (S P1 And S is P4 ) Turn off the second and third primary side switching transistors (S P2 And S is P3 ) First synchronous rectification switch tube S R1 During the course of (1) the synchronous rectification driver CS pin voltage v CS And a first synchronous rectifying tube S R1 Voltage v across drain and source of (2) DSR1 There is the following relationship in the frequency domain:
the transfer function has a zero and a pole corresponding to a frequency f z And f p The method comprises the following steps of:
design f z <0.5f p And (2) and
wherein k is SR For the first synchronous rectifying tube S R1 Switching on the voltage v at the two ends of the front drain and the source DSR1 Is a voltage drop slope of (2); for a dual clamp zero voltage converter, deltaV PK Has a value of (V o1 +V in1 /n)。
To further illustrate the effectiveness of the compensation method and circuit of the present invention, fig. 7 and 8 show experimental waveform comparison diagrams and experimental efficiency comparison curves, respectively, for specific embodiments. As can be seen from the figure, the patch according to the invention is usedAfter compensation method and circuit, first synchronous rectifier S R1 The turn-on delay of the converter is reduced from 55ns to 35ns, so that the turn-on time of the body diode is obviously reduced, the turn-on loss is reduced, the efficiency of the converter is obviously improved within a wide load range, and the full-load efficiency is improved by more than 2%. The compensation method and the compensation circuit provided by the invention are simple to realize, do not need signal isolation transmission, are beneficial to improving the power density of the converter, and are particularly suitable for power conversion occasions requiring high frequency and high efficiency.
The foregoing is only a preferred embodiment of the invention, it being noted that: it will be apparent to those skilled in the art that several modifications and variations can be made without departing from the principles of the invention, and such modifications and variations are to be regarded as being within the scope of the invention.

Claims (7)

1. A compensating circuit for synchronous rectifier tube turn-on delay is characterized in that an on enabling signal is generated by detecting the drain-source voltage falling edge before the synchronous rectifier tube is turned on; the synchronous rectifier is a synchronous rectifier in a dual clamp zero voltage converter comprising a first primary switching tube (S P1 ) Second primary side switch tube (S) P2 ) Third primary side switch tube (S) P3 ) Fourth primary side switch tube (S) P4 ) First power transformer (T) 1 ) A first clamp capacitor (C L1 ) Synchronous rectifying tube (S) R1 ) And a first output filter capacitor (C o1 ) The first power transformer (T 1 ) Is the first excitation inductance (L m1 ) The method comprises the steps of carrying out a first treatment on the surface of the The first primary side switching tube (S P1 ) Through the drain of the input voltage V in1 Is grounded, the source electrode of the second primary side switch tube is connected with the second primary side switch tube (S P2 ) A drain electrode of (2); the second primary side switch tube (S P2 ) The source electrode of the third primary side switch tube is grounded (S P3 ) Through a first clamp capacitance (C L1 ) Is connected with a fourth primary side switch tube (S) P4 ) Is grounded, a third primary switch tube (S P3 ) The source electrode of the (S) is connected with a fourth primary side switch tube (S P4 ) A drain electrode of (2); the first primary side switching tube (S P1 ) Is opened with the third primary sideClosing tube (S) P3 ) Is connected to the source of the first power transformer (T) 1 ) Both ends of the primary side and a first excitation inductance (L m1 ) Is provided; the first output filter capacitor (C o1 ) Connected in parallel with the load, one end of the first power transformer (T 1 ) One end of the secondary side is grounded and connected with the synchronous rectifying tube (S R1 ) Source of synchronous rectifying tube (S) R1 ) Is connected to the drain of the first power transformer (T) 1 ) The other end of the secondary side;
the compensation circuit comprises a first compensation capacitor (C f ) A first compensation resistor (R f1 ) And a second compensation resistor (R f2 ) The first compensation capacitor (C f ) And a second compensation resistor (R f2 ) In parallel, a first compensation capacitor (C f ) One end of the first compensation resistor is connected with the drain electrode of the synchronous rectifying tube, and the other end is connected with the drain-source voltage detection pin (CS) of the synchronous rectifying driver and the first compensation resistor (R f1 ) Is a first compensation resistor (R f1 ) The other end of the transistor is connected with the source electrode of the synchronous rectifying tube.
2. The synchronous rectifier turn-on delay compensation circuit according to claim 1, further comprising a first compensation switching tube (S f1 ) The first compensation switch tube (S f1 ) And a first compensation capacitor (C f ) And a second compensation resistor (R f2 ) Parallel, first compensation switch tube (S f1 ) One end of the first compensation resistor is connected with the drain electrode of the synchronous rectifying tube, and the other end is connected with the drain-source voltage detection pin (CS) of the synchronous rectifying driver and the first compensation resistor (R f1 ) Is provided.
3. The synchronous rectifier turn-on delay compensation circuit according to claim 1, further comprising a second compensation switching tube (S f2 ) The first compensation resistor (R f1 ) The other end of (S) passes through a second compensation switch tube (S f2 ) And the source electrode of the synchronous rectifying tube is connected.
4. A synchronous integer according to claim 3A compensating circuit for the turn-on delay of a flow tube, characterized in that the control circuit of the compensating circuit comprises a first NOT gate (N 1 ) Has a signal input end and two signal output ends, wherein the signal input end is connected with an output pin (OUT) of the synchronous rectification driver, and the two signal output ends respectively output a first compensation switch tube (S f1 ) And a second compensation switch tube (S f2 ) Control signal v of (2) GSf1 And v GSf2 The method comprises the steps of carrying out a first treatment on the surface of the The voltage signal at the output pin (OUT) of the synchronous rectifying driver is directly used for controlling the first compensating switch tube (S f1 ) Is switched on and off by a first NOT gate (N 1 ) After the phase inversion, is used for controlling a second compensation switch tube (S f2 ) When the synchronous rectifying tube is turned on, the first compensating switching tube is turned on (S f1 ) And turn off the second compensation switch tube (S f2 ) When the synchronous rectifying tube is turned off, the first compensation switching tube is turned off (S f1 ) And turn on the second compensation switch tube (S) f2 )。
5. The synchronous rectifier turn-on delay compensation circuit of claim 1, wherein the first compensation resistor (R f1 ) And a second compensation resistor (R f2 ) The following relationship is satisfied:
wherein V is CS_min The maximum negative voltage value DeltaV allowed to be applied by a drain-source voltage detection pin (CS) of the synchronous rectification driver PK Switching on the voltage conversion quantity of the voltages at the two ends of the front drain and the source for the synchronous rectifying tube; r is R f1 For the resistance value of the first compensation resistor, R f2 The resistance value of the second compensation resistor.
6. The synchronous rectifier turn-on delay compensation circuit of claim 5 wherein the drain-source voltage sense (CS) pin voltage v of the synchronous rectifier driver CS And synchronous rectifying tube (S) R1 ) Voltage v across drain and source of (2) DSR1 At frequencyThe following transfer functions exist over the domain:
the zero and the pole of the transfer function respectively correspond to the frequency f z And f p ：
Wherein C is f Is the capacitance value of the first compensation capacitor.
7. The synchronous rectifier turn-on delay compensation circuit of claim 6 wherein f z And f p The relation of (2) is:
f z <0.5f p
and:
wherein k is SR Is a synchronous rectifying tube (S) R1 ) Switching on the voltage v at the two ends of the front drain and the source DSR1 Is a voltage drop slope of (a).
CN202210242688.9A 2022-03-11 2022-03-11 Compensation method and circuit for synchronous rectifier tube turn-on delay Active CN114598159B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202210242688.9A CN114598159B (en) 2022-03-11 2022-03-11 Compensation method and circuit for synchronous rectifier tube turn-on delay

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202210242688.9A CN114598159B (en) 2022-03-11 2022-03-11 Compensation method and circuit for synchronous rectifier tube turn-on delay

Publications (2)

Publication Number Publication Date
CN114598159A CN114598159A (en) 2022-06-07
CN114598159B true CN114598159B (en) 2023-07-21

Family

ID=81818402

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202210242688.9A Active CN114598159B (en) 2022-03-11 2022-03-11 Compensation method and circuit for synchronous rectifier tube turn-on delay

Country Status (1)

Country Link
CN (1) CN114598159B (en)

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111146961A (en) * 2020-01-20 2020-05-12 昂宝电子（上海）有限公司 Control circuit and method for controlling synchronous rectification system

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20120063175A1 (en) * 2010-09-10 2012-03-15 Dong Wang Compensation circuit and method for a synchronous rectifier driver
CN102882377B (en) * 2012-09-20 2014-11-05 矽力杰半导体技术(杭州)有限公司 Synchronous rectifying control method and circuit
US9608532B2 (en) * 2015-04-04 2017-03-28 Joulwatt Technology Inc. Limited Body diode conduction optimization in MOSFET synchronous rectifier
CN208608911U (en) * 2018-07-23 2019-03-15 四川升华电源科技有限公司 It is non-delay partly to drive rectifier certainly from driving rectification circuit and non-delay half
CN111953184A (en) * 2020-07-17 2020-11-17 上海百功半导体有限公司 Isolated power supply synchronous rectification device and method
CN215580941U (en) * 2021-04-08 2022-01-18 昂宝电子（上海）有限公司 Synchronous rectification controller and synchronous rectification system

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN111146961A (en) * 2020-01-20 2020-05-12 昂宝电子（上海）有限公司 Control circuit and method for controlling synchronous rectification system

Also Published As

Publication number Publication date
CN114598159A (en) 2022-06-07

Similar Documents

Publication Publication Date Title
KR100691929B1 (en) General self-driven synchronous rectification scheme for synchronous rectifiers having a floating gate
US7385833B2 (en) Snubber circuit for a power converter
US7433209B2 (en) Soft-switching DC/DC converter having relatively better effectiveness
US6191960B1 (en) Active clamp for isolated power converter and method of operating thereof
Dudrik et al. Zero-voltage and zero-current switching full-bridge DC–DC converter with auxiliary transformer
US11770076B2 (en) System and method for controlling active clamp flyback converter
CN103066855B (en) System and method used for no-voltage switch in power source transformation system
CN205960954U (en) Turn over and swash control circuit
Song et al. Dual-bridge DC-DC converter: A new topology characterized with no deadtime operation
CN108448902A (en) A kind of synchronous rectification inverse-excitation type DC-DC power conversion equipment and control method
WO2021031792A1 (en) Tlc resonance circuit, and power converter applying same
CN105406724A (en) Phase-shifting control full-bridge zero-current converter and direct-current switching power source
CN210297551U (en) DCDC boost converter
CN114598159B (en) Compensation method and circuit for synchronous rectifier tube turn-on delay
CN112039316A (en) Primary side feedback type switching power supply circuit, control method and switching power supply
CN109713905B (en) CCM/DCM multiplexing single-coupling inductance multi-output buck converter
CN108900096B (en) Synchronous rectification power supply circuit with absorption function
EP4040661A1 (en) Soft-switching power converter
CN115149809A (en) Non-isolated full-bridge cascaded converter circuit and control method thereof
CN114337261A (en) Control system of synchronous rectifier tube in four-switch buck-boost converter
CN114070019A (en) Drive circuit, drive method and switching power supply
CN113783426A (en) Synchronous coupling Boost circuit, Boost circuit and power supply device
Lee et al. Novel switching control method for synchronous rectifier of phase-shifted full-bridge converter in light-load conditions
WO2019218706A1 (en) Dc-dc converter
CN112003476B (en) Control method for reducing conduction time of ACF power tube body diode

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
TA01 Transfer of patent application right
TA01 Transfer of patent application right

Effective date of registration: 20230627

Address after: 201306 building C, No. 888, Huanhu West 2nd Road, Lingang New District, China (Shanghai) pilot Free Trade Zone, Pudong New Area, Shanghai

Applicant after: SHANGHAI JIERUIZHAO NEW INFORMATION TECHNOLOGY CO.,LTD.

Address before: 222061 No.18, Shenghu Road, Haizhou District, Lianyungang City, Jiangsu Province

Applicant before: LIANYUNGANG JIERUI ELECTRONIC Co.,Ltd.

GR01 Patent grant
GR01 Patent grant