CN113595398A - Control device and control method - Google Patents

Control device and control method Download PDF

Info

Publication number
CN113595398A
CN113595398A CN202110747537.4A CN202110747537A CN113595398A CN 113595398 A CN113595398 A CN 113595398A CN 202110747537 A CN202110747537 A CN 202110747537A CN 113595398 A CN113595398 A CN 113595398A
Authority
CN
China
Prior art keywords
flyback converter
auxiliary switch
signal
negative current
control
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.)
Granted
Application number
CN202110747537.4A
Other languages
Chinese (zh)
Other versions
CN113595398B (en
Inventor
宋海斌
章进法
许道飞
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.)
Delta Electronics Shanghai Co Ltd
Original Assignee
Delta Electronics Shanghai 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 Delta Electronics Shanghai Co Ltd filed Critical Delta Electronics Shanghai Co Ltd
Priority to CN202110747537.4A priority Critical patent/CN113595398B/en
Publication of CN113595398A publication Critical patent/CN113595398A/en
Application granted granted Critical
Publication of CN113595398B publication Critical patent/CN113595398B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

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
    • 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
    • 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)

Abstract

The disclosure relates to a control device and a control method, which are applied to a flyback converter, wherein the flyback converter comprises an auxiliary switch. The control device includes: the on-time setting unit is used for setting an on-time threshold according to the exciting negative current reference value and the output voltage of the flyback converter; and the conduction time control unit is used for outputting a control signal to control the conduction of the auxiliary switch and switching off the auxiliary switch when the conduction time of the auxiliary switch reaches the conduction time threshold value. The zero-voltage switching-on of the primary side switching tube of the flyback converter under different output voltages can be realized.

Description

Control device and control method
This application is a divisional application of patent application No. 201710524232.0 entitled "control device and control method", which is incorporated herein in its entirety.
Technical Field
The disclosure relates to the technical field of power electronics, and in particular relates to a control device and a control method applied to a flyback converter.
Background
At present, the quasi-resonant flyback converter is the most popular circuit topology structure applied to a low-power switching power supply. Quasi-resonant flyback converter with low voltage input (V)bus<nVoWherein: vbusIs the input voltage; n is the turn ratio of the primary side coil and the secondary side coil of the transformer; voOutput voltage) can realize zero voltage switching-on (ZVS) of the primary side power switch tube, and the zero voltage switching-on (ZVS) can be realized at high voltage input (V)bus>nVo) The valley bottom of the primary side power switch tube can be switched on, so that the switching loss can be obviously reduced. However, with the development of high frequency, although the quasi-resonant flyback converter can realize valley-bottom switching when high voltage is input, the switching loss still becomes larger and larger, and the efficiency of the converter is seriously influenced. In order to solve the problem that Zero Voltage Switching (ZVS) of a primary side power switching tube cannot be completely realized when a quasi-resonant flyback converter is in high-voltage input, the prior art scheme provides a new control method for delay conduction of a secondary side synchronous rectifier tube and the like and a new circuit topology structure for an active clamp flyback converter and the like.
However, the prior art is only suitable for the case of constant output voltage, and cannot ensure that zero-voltage switching-on of the primary side power switch tube can be realized under all working conditions under the application condition of variable output voltage.
It is to be noted that the information disclosed in the above background section is only for enhancement of understanding of the background of the present disclosure, and thus may include information that does not constitute prior art known to those of ordinary skill in the art.
Disclosure of Invention
An object of the present disclosure is to provide a control apparatus and a control method, thereby overcoming, at least to some extent, one or more of the problems due to the limitations and disadvantages of the related art.
According to an aspect of the present disclosure, there is provided a control device for a flyback converter, the flyback converter including an auxiliary switch, the control device comprising:
the on-time setting unit is used for setting an on-time threshold according to an exciting negative current reference value and the output voltage of the flyback converter; and
and the conduction time control unit is used for outputting a control signal to control the conduction of the auxiliary switch, and turning off the auxiliary switch when the conduction time of the auxiliary switch reaches the conduction time threshold value.
In an exemplary embodiment of the present disclosure, the flyback converter is an RCD clamped flyback converter or an active clamped flyback converter.
In an exemplary embodiment of the disclosure, the auxiliary switch is a synchronous rectifier, a clamp, a switch connected in parallel to a secondary side rectifying unit of the flyback converter, or a switch connected in series to an auxiliary winding of the flyback converter.
In an exemplary embodiment of the disclosure, the on-time control unit is configured to output the control signal according to a timing start signal.
In an exemplary embodiment of the present disclosure, an operation mode of the flyback converter is a discontinuous mode or a critical continuous mode.
In an exemplary embodiment of the present disclosure, the on-time control unit includes a timer and an auxiliary switch controller,
the timer receives a timing starting signal and starts the timer to time according to the timing starting signal to generate a timing signal;
the auxiliary switch controller receives the timing signal and generates the control signal according to the timing signal.
In an exemplary embodiment of the present disclosure, the auxiliary switch controller turns on the auxiliary switch according to the timing start signal.
In an exemplary embodiment of the present disclosure, the auxiliary switch controller turns off the auxiliary switch when the timing signal is greater than or equal to the on-time threshold.
In an exemplary embodiment of the present disclosure, the timer further resets the timer according to a reset signal.
In an exemplary embodiment of the present disclosure, in an intermittent mode, the timing start signal is obtained by detecting an on signal of the auxiliary switch; and under a critical continuous mode, obtaining the timing starting signal by detecting the zero crossing point of the exciting negative current in the flyback converter.
In an exemplary embodiment of the present disclosure, the zero-crossing point of the exciting negative current is detected by a current transformer, a sampling resistor, or an internal resistance of the auxiliary switch itself.
In an exemplary embodiment of the present disclosure, the reset signal is obtained by detecting an off signal of the auxiliary switch.
In an exemplary embodiment of the present disclosure, the on-time setting unit includes:
the excitation negative current setting unit is used for generating the reference value of the excitation negative current;
and the conduction time calculation unit is used for calculating to obtain the conduction time threshold according to the exciting negative current reference value and the output voltage of the flyback converter.
In an exemplary embodiment of the present disclosure, the excitation negative current setting unit is configured to set the excitation negative current reference value based on an input voltage of the flyback converter.
In an exemplary embodiment of the present disclosure, the excitation negative current setting unit is configured to set the excitation negative current reference value based on an input voltage of the flyback converter and an output voltage of the flyback converter.
In an exemplary embodiment of the present disclosure, an output voltage of the flyback converter is variable.
In an exemplary embodiment of the present disclosure, the output voltage of the flyback converter is 5V, 9V, 15V, or 20V.
According to an aspect of the present disclosure, there is provided a switching power supply comprising a control device according to any one of the above.
According to an aspect of the present disclosure, a control method is provided for a flyback converter, the flyback converter including an auxiliary switch, the control method including:
(a) detecting the output voltage of the flyback converter, and setting a conduction time threshold value based on the output voltage and an excitation negative current reference value;
(b) and controlling the conduction of the auxiliary switch according to a control signal, and turning off the auxiliary switch when the conduction time of the auxiliary switch reaches the conduction time threshold value.
In an exemplary embodiment of the present disclosure, the flyback converter is an RCD clamped flyback converter or an active clamped flyback converter.
In an exemplary embodiment of the disclosure, the auxiliary switch is a synchronous rectifier, a clamp, a switch connected in parallel to a secondary side rectifying unit of the flyback converter, or a switch connected in series to an auxiliary winding of the flyback converter.
In one exemplary embodiment of the present disclosure, the step (b) comprises: and outputting the control signal according to a timing starting signal.
In an exemplary embodiment of the present disclosure, an operation mode of the flyback converter is a discontinuous mode or a critical continuous mode.
In one exemplary embodiment of the present disclosure, the step (b) includes: starting a timer to time according to a timing starting signal to generate a timing signal; generating the control signal according to the timing signal.
In an exemplary embodiment of the present disclosure, the auxiliary switch is turned on according to the timing start signal.
In an exemplary embodiment of the disclosure, the auxiliary switch is turned off when the timing signal is greater than or equal to the on-time threshold.
In an exemplary embodiment of the present disclosure, the step (b) further comprises: and resetting the timer according to a reset signal.
In an exemplary embodiment of the present disclosure, in an intermittent mode, the timing start signal is obtained by detecting an on signal of the auxiliary switch; and under a critical continuous mode, obtaining the timing starting signal by detecting the zero crossing point of the exciting negative current in the flyback converter.
In an exemplary embodiment of the present disclosure, the zero-crossing point of the exciting negative current is detected by a current transformer, a sampling resistor, or an internal resistance of the auxiliary switch itself.
In an exemplary embodiment of the present disclosure, the reset signal is obtained by detecting an off signal of the auxiliary switch.
In one exemplary embodiment of the present disclosure, the step (a) includes: and calculating and obtaining the conduction time threshold value based on the output voltage and the exciting negative current reference value through division operation.
In an exemplary embodiment of the present disclosure, the control method further includes: (c) and after the auxiliary switch is turned off, realizing zero voltage switching-on of a primary side power switch tube of the flyback converter through resonance of an excitation inductor and a parasitic capacitor in the flyback converter.
In an exemplary embodiment of the present disclosure, the step (a) further includes: and setting the exciting negative current reference value based on the input voltage of the flyback converter.
In an exemplary embodiment of the present disclosure, the step (a) further includes: and setting the exciting negative current reference value based on the maximum value of the input voltage of the flyback converter.
In an exemplary embodiment of the present disclosure, the step (a) further includes: and setting the exciting negative current reference value based on the input voltage of the flyback converter and the output voltage of the flyback converter.
In an exemplary embodiment of the present disclosure, an output voltage of the flyback converter is variable.
In an exemplary embodiment of the present disclosure, the output voltage of the flyback converter is 5V, 9V, 15V, or 20V.
According to the control device and the control method of the embodiment of the disclosure, the on-time threshold is set according to the exciting negative current reference value and the output voltage of the flyback converter, the control signal is output to control the auxiliary switch to be turned on, and the auxiliary switch is turned off when the on-time of the auxiliary switch reaches the on-time threshold. On one hand, the conduction time threshold values under different voltage states can be set in real time through the exciting negative current reference value and the output voltage of the flyback converter monitored in real time; on the other hand, the conducting time of the auxiliary switch is adjusted in real time according to the conducting time threshold value so that the conducting time of the auxiliary switch follows the conducting time threshold value, and therefore zero-voltage switching-on of a primary side power switch tube in the flyback converter under different output voltages can be achieved.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.
Drawings
Fig. 1 schematically shows a circuit diagram of an active clamp flyback converter in one embodiment.
Fig. 2 schematically shows a discontinuous mode control waveform diagram of an active clamp flyback converter in a technical scheme.
Fig. 3 schematically shows a circuit diagram of an RCD clamped flyback converter in a technical solution.
Fig. 4 schematically shows a critical continuous mode control waveform diagram of an RCD clamped flyback converter in a technical solution.
Fig. 5 schematically shows a circuit diagram of an RCD clamped flyback converter in another technical solution.
Fig. 6 schematically illustrates a control schematic block diagram of a control apparatus according to an exemplary embodiment of the present disclosure.
Fig. 7 schematically shows a control schematic block diagram of a control apparatus according to another exemplary embodiment of the present disclosure.
Fig. 8 schematically shows a circuit diagram of an on-time control unit according to yet another exemplary embodiment of the present disclosure.
Fig. 9 schematically illustrates a discontinuous mode control waveform diagram for an RCD clamped flyback converter, according to yet another exemplary embodiment of the present disclosure.
Fig. 10 schematically illustrates critical continuous mode control waveform diagrams for an active clamp flyback converter according to yet another exemplary embodiment of the present disclosure.
Fig. 11 schematically illustrates a specific embodiment of a method of on-time control of an RCD clamped flyback converter according to yet another exemplary embodiment of the present disclosure.
Fig. 12 schematically illustrates one specific embodiment of a method of on-time control of an active-clamp flyback converter according to yet another exemplary embodiment of the present disclosure.
Fig. 13 schematically illustrates one specific embodiment of a setting method of an excitation negative current reference value of an RCD clamped flyback converter as a function of an input voltage according to yet another exemplary embodiment of the present disclosure.
Fig. 14 schematically illustrates one specific embodiment of a setting method of an excitation negative current reference value of an active clamp flyback converter varying with an input voltage according to yet another exemplary embodiment of the present disclosure.
Fig. 15 schematically shows a flow chart of a control method according to yet another exemplary embodiment of the present disclosure.
Description of reference numerals:
S1: primary side power switch tube
S2: clamping tube
SR: synchronous rectifier tube
Is: secondary side current
t0-t 5: time of day
Lm: exciting inductance
Vo: output voltage
CEQ: parasitic capacitance
Im_n(t): amplitude of the excited negative current
Saux: switch connected in parallel to diode D1
Waux: auxiliary winding
Saux_VCC: switch connected in series with auxiliary winding
600. 1100, 1200, 1400, 1500: control device
610. 1110, 1210, 1410, 1510: flyback converter
620: on-time setting unit
630. 1130, 1230, 1430, 1530: on-time control unit
640. 1140, 1240, 1440, 1540: excitation negative current setting unit
650. 1150, 1250, 1450, 1550: on-time calculation unit
1480. 1580: input voltage detection unit
810: time-meter
820: auxiliary switch controller
Im_N: reference value of exciting negative current
tset: on time threshold
T: transformer device
Co: output capacitor
Vbus: input voltage
R1: a first resistor
R2: second resistance
(a) (b), (c): step (ii) of
Detailed Description
Some exemplary embodiments that incorporate the features and advantages of the present disclosure will be described in detail in the specification which follows. It is to be understood that the present disclosure is capable of various modifications in various embodiments, all without departing from the scope of the present disclosure, and that the description and illustrations herein are intended to be taken as illustrative of the modifications and not limiting of the disclosure.
Fig. 1 shows a circuit diagram of an active clamp flyback converter in one embodiment. The active clamp flyback converter can realize a primary side power switch tube S1The conventional control method is as follows: control clamp tube S2Power switch tube S only on primary side1Before conducting, conducting for a set time, which is t2-t3 in the control waveform diagram shown in FIG. 2.
Fig. 3 shows a circuit diagram of an RCD clamped flyback converter in one embodiment. RCD clamping flyback converter through secondary side synchronous rectifier S of delay conduction quasi-resonant flyback converterRTo realize the primary side power switch tube S1Zero voltage turn-on (ZVS), existing secondary side synchronous rectifier SRThe delay conduction control method comprises the following steps: controlling synchronous rectifiers SRAt the secondary side current IsAfter dropping to zero, the conduction continues for a set time, which is t1-t2 in the control waveform diagram shown in FIG. 4.
The two types of the power switch tube S for realizing the primary side1The Zero Voltage Switching (ZVS) method is realized by controlling the synchronous rectifier tube SROr clamping tube S2The set time is switched on, which is applicable for fixed output voltage applications.
However, with the development of power adapters, especially the popularization and popularity of USB-PD Type-C, the application of varying output voltages is becoming more and more popular. For variable output voltage applications, the above control scheme is no longer applicable because: whether it is an RCD clamp flyback converter or an active clamp flyback converter, the basic principle of implementing Zero Voltage Switching (ZVS) of a primary side power switch tube is as follows: at the primary side of the power switch tube S1Before the switch-on, the exciting inductance L of the transformer is enabledmGenerating an exciting negative current Im_nBy the exciting negative current Im_nTo realize the primary side power switch tube S1Is turned on (ZVS), and the magnitude of the exciting negative current is determined by the following formula:
Figure BDA0003144866310000081
wherein: l ismIs the exciting inductance value of the transformer, n is the turns ratio of the transformer, VoIs the output voltage value of the converter, Im_n(t) is the amplitude of the excited negative current, t is the conduction time of the auxiliary switch (for a synchronous rectifier of a quasi-resonant flyback converter, this is the secondary side current I)sThe conduction time after the conduction time drops to zero refers to the conduction time before the primary side power switch tube is conducted for the clamp tube of the active clamp flyback converter).
From the above equation, it can be seen that for a fixed design, the value of the excitation inductance LmAnd the turns ratio n is fixed. If the output voltage Vo is fixed, the fixed on-time t means a fixed magnitude of the excited negative current, as can be seen from equation (1), and thus, by controlling the synchronous rectifier SROr clamping tube S2Turning on for a set time t is applicable to the application of fixed output voltage. If the output voltage is variable, the fixed on-time means that the magnitude of the excited negative current will follow the output voltage VoMay be changed. Taking the application of USB-PD Type-C as an example, the minimum output voltage is 5V, and the maximum output voltage is 20V, if the control method with fixed on-time is adopted, one of the following two results will be obtained:
a: if the set on-time just meets the condition of zero voltage switch-on (ZVS) of the primary side power switching tube when the output voltage is 5V, the amplitude of the generated exciting negative current is 4 times that of the exciting negative current when the output voltage is 5V when the output voltage is 20V. Excessive negative exciting current introduces extra loss, affecting the efficiency of the converter.
B: if the set on-time just meets the condition of zero voltage switching-on (ZVS) of the primary side power switching tube when the output voltage is 20V, when the output voltage is 5V, the amplitude of the generated exciting negative current is only 1/4 when the output voltage is 20V, and the zero voltage switching-on of the primary side power switching tube cannot be realized due to the excessively small amplitude of the exciting negative current.
Based on the above, in the present exemplary embodiment, first, a control device is provided, and referring to fig. 6, the control device 600 is used for controlling the flyback converter 610, wherein the flyback converter 610 includes an auxiliary switch. As shown in fig. 6, the control device 600 may include: an on-time setting unit 620, and an on-time control unit 630. Wherein:
the on-time setting unit 620 is used for setting the on-time according to the reference value of the exciting negative current and the output voltage VoSetting a threshold value t of the on-timeset(ii) a And
the on-time control unit 630 is used for outputting a control signal to control the auxiliary switch to be turned on when the on-time of the auxiliary switch reaches the on-time threshold tsetThe auxiliary switch is turned off. For example, the control signal may be based on the timing start signal and the on-time threshold tsetAnd obtaining the compound.
According to the control device of the embodiment, on one hand, the on-time threshold values under different voltage states can be set in real time through an exciting negative current reference value and the output voltage of the flyback converter circuit monitored in real time; on the other hand, the conducting time of the auxiliary switch is adjusted in real time according to the conducting time threshold value so that the conducting time of the auxiliary switch follows the conducting time threshold value, and therefore zero voltage switching-on of a primary side power switch tube in the flyback converter under different output voltages can be achieved.
In this example embodiment, the flyback converter further includes a primary side switching unit, a secondary side rectifying unit, a transformer, and an output capacitor, where the primary side switching unit includes a primary side power switching tube, and the secondary side rectifying unit includes a first end and a second end, and the first end and the second end are electrically connected to the transformer and the output capacitor, respectively. In order to be suitable for the application situation of variable output voltage, zero voltage switching-on (ZVS) of a primary side power switch tube in a full input voltage range (for example, 90-264 Vac) and a full load range under different output voltages is realized, and the conducting time of an auxiliary switch needs to be directly controlled. According to the following formula (2):
Figure BDA0003144866310000091
from the above equation (2), it can be seen that for a set negative current reference Im_NOn time threshold tsetAnd an output voltage VoIs in inverse proportionIs described. The on-time threshold of the auxiliary switch is adjusted according to different output voltages, and then the on-time of the auxiliary switch is adjusted, so that the purpose of controlling the exciting negative current can be achieved. Therefore, the basic principle of the present disclosure is: before the primary side power switch tube is switched on, an excitation negative current is generated in the flyback converter by controlling the on and off of the auxiliary switch. Firstly, the auxiliary switch is controlled to be conducted, so that the conducting time of the auxiliary switch reaches a conducting time threshold tset. Then, the auxiliary switch is controlled to be turned off, and after the auxiliary switch is turned off, the exciting negative current is used as an initial value and passes through an exciting inductor LmParasitic capacitance C with the primary lineEQTo achieve zero voltage turn-on (ZVS) of the primary side power switching tube. According to the zero voltage switching-on method and the zero voltage switching-on device, the zero voltage switching-on (ZVS) of the primary side power switch tube can be realized in the full input voltage range and the full load range of different output voltages by reasonably setting the on-time threshold of the auxiliary switch. In the present embodiment, the parasitic capacitance CEQThe parasitic capacitance of the primary side power switching tube S1 and the parasitic capacitance of the primary side coil of the transformer T constitute the parasitic capacitance.
It should be noted that, in the present exemplary embodiment, the output voltage of the flyback converter 610 may be variable, for example, the output voltage of the flyback converter 610 may be 5V, 9V, 15V, 20V, or the like, which is not particularly limited in this disclosure.
Further, in the present example embodiment, the flyback converter 610 may be an active clamp flyback converter as shown in fig. 1 or an RCD clamp flyback converter as shown in fig. 3 and 5, but the flyback converter in the example embodiment of the present disclosure is not limited thereto. Correspondingly, in the present example embodiment, the auxiliary switch of the flyback converter 610 may be the clamp S as shown in fig. 12Or S of a synchronous rectifier as shown in FIG. 3RHowever, the auxiliary switch in the example embodiment of the present disclosure is not limited thereto. For example, the secondary side of the diode-rectified RCD-clamped flyback converter shown in fig. 5 may be a switch S connected in parallel with a diode D1 as an auxiliary switchauxOr its auxiliary switch may be in series with the auxiliary winding WauxSwitch S ofaux_VCC。
It should be noted that, in this exemplary embodiment, the operation mode of the flyback converter may be an intermittent mode or a critical continuous mode, which is not particularly limited by this disclosure.
Further, as shown in fig. 7, in the present exemplary embodiment, in order to reasonably set the excitation negative current reference value and the on-time threshold, the on-time setting unit 620 may further include: an excitation negative current setting unit 640 and an on-time calculation unit 650. The excitation negative current setting unit 640 is used for setting an excitation negative current reference value I based on the input voltage or/and the output voltage of the flyback converterm_N. The on-time calculation unit 650 is used for calculating the on-time according to the reference value I of the excited negative currentm_NAnd the output voltage V of the flyback converteroTo set the on-time threshold tset。
In an embodiment, the on-time calculation unit may include a multiplication circuit or a division circuit, but not limited thereto. The multiplication or division circuit receives an excited negative current reference value Im_NAnd the output voltage V of the flyback converteroAnd according to parameters of the circuit itself, e.g. exciting inductance LmAnd the turn ratio n of the transformer, and setting the conduction time threshold t through the calculation of the formula (2)set。
In the present exemplary embodiment, the on-time control unit 630 may be implemented in various ways. Fig. 8 shows an embodiment of the on-time control unit 630 according to the present disclosure. As shown in fig. 8, the on-time control unit includes a timer 810 and an auxiliary switch controller 820, wherein the timer 810 is configured to start timing according to a timing start signal and generate a timing signal. The auxiliary switch controller 820 is used for generating a control signal according to the timing signal.
In the present exemplary embodiment, the auxiliary switch controller 820 turns on the auxiliary switch according to the timing start signal; the timing signal is gradually increased after the timer 810 starts to time, and reaches the on-time threshold t after the time reachessetWhen so, the auxiliary switch controller 820 turns off the auxiliary switch.
In the exemplary embodiment, for the discontinuous operation mode, the timing start signal of the timer 810The sign may be obtained by an on signal of the auxiliary switch. As shown in FIG. 2, at time S at t22The rising edge jump signal of the driving signal is an opening signal of the auxiliary switch; alternatively, as shown in fig. 9, S at time t2RThe rising edge jump signal of the driving signal is an opening signal of the auxiliary switch, and the timing starting signal can be obtained by detecting the rising edge jump signal. It should be noted that the timing start signal may be synchronized with the rising edge transition signal, or may be obtained by delaying the rising edge transition signal.
Further, in the present exemplary embodiment, for the critical continuous mode, the timing start signal of the timer may be obtained by detecting the zero-crossing point of the exciting negative current (e.g., at time t1 of fig. 4). Specifically, the detection of the zero crossing point of the exciting negative current can be realized through a current transformer, a sampling resistor or the internal resistance of a power device, such as the internal resistance of an auxiliary switch.
In one embodiment, the timer 810 is further reset according to a reset signal. Further, in the present exemplary embodiment, the reset signal of the timer may be obtained by the turn-off signal of the auxiliary switch, for example, the reset signal of the timer may be synchronized with the turn-off signal of the auxiliary switch, or may be obtained by delaying the turn-off signal. As shown in FIG. 2, time S at t32The falling edge jumping signal of the driving signal is a turn-off signal of the auxiliary switch; as shown in FIG. 9, S at time t3RThe falling edge jumping signal of the driving signal is a turn-off signal of the auxiliary switch; or as shown in FIG. 10, time S at t22The falling edge jump signal of the driving signal is the turn-off signal of the auxiliary switch, and the reset signal can be obtained by detecting the falling edge jump signal. It should be noted that the reset signal may be synchronized with the falling edge transition signal, or may be obtained by delaying the falling edge transition signal.
In this exemplary embodiment, the excitation negative current is controlled by controlling the on-time of the auxiliary switch, and there are a plurality of different methods for different flyback converters, which are described below as an example for the RCD clamp flyback converter in the discontinuous mode and the active clamp flyback converter in the discontinuous mode.
Fig. 11 shows a specific embodiment of a control device. As shown in fig. 11, the control device 1100 is used for controlling the flyback converter 1110, wherein the control device 1100 includes: an on-time control unit 1130, an excitation negative current setting unit 1140, and an on-time calculation unit 1150. The flyback converter 1110 is an RCD clamped flyback converter, and includes a primary side switching unit, a secondary side rectifying unit, a transformer T, and an output capacitor CoWherein the primary side switch unit comprises a primary side power switch tube S1The secondary side rectifying unit comprises a synchronous rectifying tube SRAnd the secondary side rectifying unit is respectively connected with the transformer T and the output capacitor CoAnd (6) electrically connecting.
In this embodiment, the on-time calculation unit 1150 monitors the output voltage signal V according to real timeoAnd an excitation negative current reference value I output by the excitation negative current setting unit 1140m_NTo obtain the on-time threshold tsetAnd will turn on time threshold tsetTo the on-time control unit 1130; the control device 1100 passes through the synchronous rectifier SRTurn on the on signal for the second time (e.g., S at time t2 in fig. 9)RDrive signal) to obtain a timing start signal; the on-time control unit 1130 obtains the on-time threshold tsetAnd a timing start signal for outputting a control signal to turn on the synchronous rectifier SRAnd the on-time of the auxiliary switch reaches the on-time threshold tsetTime-cut synchronous rectifier tube SR. Meanwhile, the on-time control unit 1130 controls the on-time according to the synchronous rectifier SRThe reset signal generated by the turn-off signal.
Fig. 12 shows another embodiment of a control device. As shown in fig. 12, the control device 1200 is used for controlling the flyback converter 1210, and the control device 1200 includes: an on-time control unit 1230, an excitation negative current setting unit 1240, and an on-time calculation unit 1250. The flyback converter 1210 is an active clamp flyback converter, and includes a primary side switch unit, a secondary side rectifier unit, a transformer T and an output capacitor CoWherein the primary side switch unit comprises a primary side power switchClosing pipe S1And a clamping tube S2The secondary side rectifying unit comprises a synchronous rectifying tube SRAnd the secondary side rectifying unit is respectively connected with the transformer T and the output capacitor CoAnd (6) electrically connecting.
In an embodiment, the on-time calculation unit 1250 is based on the real-time monitored output voltage signal VoAnd an excitation negative current reference value I output by the excitation negative current setting unit 1240m_NTo obtain the on-time threshold tsetAnd will turn on time threshold tsetTo the on time control unit 1230; the control device 1200 is composed of a clamping tube S2To obtain the timing start signal.
The on-time control unit 1230 obtains the timing start signal and the on-time threshold tsetFor outputting a control signal to turn on the clamp tube S2And the on-time of the auxiliary switch reaches the on-time threshold tsetTime-off clamping tube S2. Meanwhile, the on-time control unit 1230 controls the on-time according to the clamp tube S2The off signal of (a) generates a reset signal to effect a reset.
In addition, in each example embodiment of the present disclosure, an excitation negative current setting unit is included for setting an excitation negative current reference value Im_N. For setting the reference value of the exciting negative current, the following results are found through research: at low voltage input (V)bus<nVo) In time, zero voltage switching-on (ZVS) of the primary side power tube can be realized without the help of exciting negative current; at high pressure input (V)bus>nVo) In order to realize Zero Voltage Switching (ZVS) of the primary side power tube, the minimum amplitude of the exciting negative current needs to satisfy:
Figure BDA0003144866310000131
wherein: i ism_NFor exciting a negative current reference value, VbusFor input voltage, VOIs the output voltage, and n is the turns ratio of the transformer; l ismThe inductance is the excitation inductance; cEQIs the capacitance value of the parasitic capacitance.
According toEquation (3) above, n, L for a particular circuit designmAnd CEQIs fixed, and the reference value of the exciting negative current and the input voltage V are used for realizing zero voltage switching-on (ZVS) of the primary side power tubebusAnd an output voltage VOIt is related. Therefore, the excitation negative current setting unit can adjust the reference value of the excitation negative current in real time based on the input voltage and the output voltage of the flyback converter.
However, with the above method, the reference value of the exciting negative current I is adjusted in real timem_NTwo variables need to be monitored in real time: input voltage VbusAnd an output voltage VODoing so increases the complexity of the control. Further research shows that: flyback converter at high voltage input (V)bus>nVo) the influence of the output voltage on the reference value of the excited negative current is negligible, i.e. the reference value of the excited negative current is only related to the input voltage, thus greatly simplifying the setting of the reference value of the excited negative current. Then, the above formula (3) can be simplified to the following formula (4):
Figure BDA0003144866310000132
thus, the excitation negative current setting unit can set the excitation negative current reference value based on the input voltage of the flyback converter.
In this embodiment, the setting of the reference value of the exciting negative current may be performed by the following two setting methods:
fixed reference value setting method: in order to realize zero voltage switching-on (ZVS) of a primary side power switch tube in a full input voltage range, a reference value of an excitation negative current is set according to the maximum input voltage, namely:
Figure BDA0003144866310000141
wherein: vbus_maxIs the input voltage maximum.
For a fixed reference value setting method, when the input voltage is the maximum value, zero voltage switching-on (ZVS) of a primary side power switch tube can be just met; however, when the input voltage is low, the amplitude of the excited negative current generated by the control method is larger than that of the excited negative current required for realizing zero voltage switching-on (ZVS) of the primary side power tube, so that extra loss is brought, and efficiency optimization is not facilitated. Fixed reference value settings may be used in applications where efficiency requirements are not very high.
For applications with higher efficiency requirements, the efficiency of the converter can be optimized by using a setting method in which the reference value changes with the input voltage. Therefore, the excitation negative current reference value can be set to:
Figure BDA0003144866310000142
wherein: i ism_N(Vbus) Is the reference value of the exciting negative current.
Exciting inductance value L for a particular circuit designmAnd parasitic capacitance value CEQIs fixed, and the reference value of the excited negative current and the input voltage V are known from the above formula (6)busIn direct proportion, the exciting negative current setting unit can set the input voltage value V detected by the input voltage detection unitbusDirectly calculated as the reference value I of the exciting negative currentm_N。
Fig. 13 shows a further embodiment of a control device. Fig. 13 is similar to fig. 11, but fig. 13 also includes an embodiment of an excited negative current setting unit. As shown in fig. 13, the control device further includes an input voltage detecting unit 1480, and in the present embodiment, the input voltage detecting unit 1480 includes a first resistor R1And a second resistor R2And through the first resistor R1And a second resistor R2Detecting input voltage V by voltage divisionbus. The input voltage detecting unit 1480 converts the input voltage VbusInput to the exciting negative current setting unit 1440 for setting the reference value of exciting negative current Im_NExciting a negative current reference value Im_NDelivered to the on time calculation unit 1450The on-time calculation unit 1450 uses the reference value I of the excited negative currentm_NAnd real-time monitored output voltage VoTo calculate the on-time threshold tsetWill turn on time threshold tsetInput to the on time control unit 1430; second pass enable signal through synchronous rectifier (fig. 9, S at time t 2)RA driving signal) to obtain a timing start signal to enable the on time control unit 1430; the on-time control unit 1430 acquires the on-time threshold tsetAnd a timing start signal for outputting a control signal to turn on the synchronous rectifier SRAnd the on-time of the auxiliary switch reaches the on-time threshold tsetTime-cut synchronous rectifier tube SR. Meanwhile, the turn-on time control unit 1430 controls the turn-on time according to the synchronous rectification tube SRThe reset signal generated by the turn-off signal.
Fig. 14 shows a further embodiment of a control device. Fig. 14 is similar to the structure of fig. 12, the main difference being that the auxiliary switch in fig. 14 is the clamp S on the primary side of the active clamp flyback converter2。
Furthermore, in the present exemplary embodiment, a control method is also provided, where the control method may be applied to a flyback converter as shown in fig. 6 to 14, where the flyback converter includes an auxiliary switch, and as shown in fig. 15, the control method may include the following steps: step (a): detecting the output voltage of the flyback converter, and setting a conduction time threshold value based on the output voltage and the reference value of the exciting negative current; step (b): and controlling the auxiliary switch to be switched on according to the control signal, and switching off the auxiliary switch when the switching-on time of the auxiliary switch reaches a switching-on time threshold value.
On one hand, the on-time threshold values under different voltage states can be set in real time through an excitation negative current reference value and the output voltage of the flyback converter monitored in real time; on the other hand, the conducting time of the auxiliary switch is adjusted in real time according to the conducting time threshold value so that the conducting time of the auxiliary switch follows the conducting time threshold value, and therefore zero voltage switching-on of a primary side power switch tube in the flyback converter under different output voltages can be achieved.
Further, in the present exemplary embodiment, the auxiliary switch may be a synchronous rectifier, a clamp, a switch connected in parallel to the secondary side rectifying unit of the flyback converter, or a switch connected in series to the auxiliary winding of the flyback converter.
Further, in the present exemplary embodiment, in the discontinuous mode, the timing start signal may be obtained by detecting the on signal of the auxiliary switch; and in the critical continuous mode, a timing starting signal can be obtained by detecting the zero crossing point of the exciting negative current.
Further, in the present example, the step (a) may further include: and calculating to obtain the conduction time threshold value based on the output voltage and the exciting negative current reference value through division operation.
Furthermore, in the present exemplary embodiment, the control method may further include: (c) after the auxiliary switch is turned off, the zero voltage switching-on of a primary side power switch tube of the flyback converter is realized through the resonance of an excitation inductor and a parasitic capacitor in the flyback converter.
Since each step in the control method in this exemplary embodiment corresponds to a function of each unit or module of the control device, which will not be described herein again.
Further, another preferred embodiment of the present disclosure provides a switching power supply, which may include any one of the control devices in the foregoing embodiments. Since the switching power supply in this preferred embodiment employs the above-described control device, it has at least all the advantages corresponding to the control device.
Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any variations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.
It will be understood that the present disclosure is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims (37)

1. A control apparatus for a flyback converter with a variable output voltage, the flyback converter including an auxiliary switch, the control apparatus comprising:
the conduction time setting unit is used for setting different conduction time thresholds in different output voltage states in real time according to an excitation negative current reference value and the output voltage of the flyback converter; and
and the conduction time control unit is used for outputting a control signal to control the conduction of the auxiliary switch, and turning off the auxiliary switch when the conduction time of the auxiliary switch reaches the conduction time threshold value.
2. The control apparatus of claim 1, wherein the flyback converter is an RCD clamped flyback converter or an active clamped flyback converter.
3. The control apparatus of claim 1, wherein the auxiliary switch is a synchronous rectifier, a clamp, a switch connected in parallel to a secondary side rectifying unit of the flyback converter, or a switch connected in series to an auxiliary winding of the flyback converter.
4. The control device as claimed in claim 1, wherein the on-time control unit is configured to output the control signal according to a timing start signal.
5. The control device of claim 1, wherein the operating mode of the flyback converter is a discontinuous mode or a critical continuous mode.
6. The control apparatus of claim 1, wherein the on-time control unit includes a timer and an auxiliary switch controller,
the timer receives a timing starting signal and starts the timer to time according to the timing starting signal to generate a timing signal;
the auxiliary switch controller receives the timing signal and generates the control signal according to the timing signal.
7. The control apparatus of claim 6, wherein the auxiliary switch controller turns on the auxiliary switch according to the timing start signal.
8. The control apparatus of claim 6, wherein the auxiliary switch controller turns off the auxiliary switch when the timing signal is greater than or equal to the on-time threshold.
9. The control device of claim 6, wherein the timer is further reset in response to a reset signal.
10. The control apparatus according to claim 6, wherein the timing start signal is obtained by detecting an on signal of the auxiliary switch in a discontinuous mode; and under a critical continuous mode, obtaining the timing starting signal by detecting the zero crossing point of the exciting negative current in the flyback converter.
11. The control apparatus of claim 10, wherein the zero-crossing point of the excited negative current is detected by a current transformer, a sampling resistor, or an internal resistance of the auxiliary switch itself.
12. The control apparatus of claim 9, wherein the reset signal is obtained by detecting an off signal of the auxiliary switch.
13. The control device according to claim 1, wherein the on-time setting unit includes:
the excitation negative current setting unit is used for generating the reference value of the excitation negative current;
and the conduction time calculation unit is used for calculating to obtain the conduction time threshold according to the exciting negative current reference value and the output voltage of the flyback converter.
14. The control device according to claim 13, wherein the excitation negative current setting unit is configured to set the excitation negative current reference value based on an input voltage of the flyback converter.
15. The control device according to claim 13, wherein the excitation negative current setting unit is configured to set the excitation negative current reference value based on an input voltage of the flyback converter and an output voltage of the flyback converter.
16. The control apparatus of claim 1, wherein the minimum magnitude of the negative excitation current is such that:
Figure FDA0003144866300000021
wherein: i ism_NFor exciting a negative current reference value, VbusFor input voltage, VOIs the output voltage, and n is the turns ratio of the transformer; l ismThe inductance is the excitation inductance; cEQIs the capacitance value of the parasitic capacitance.
17. The control device of claim 1, wherein the output voltage of the flyback converter is 5V, 9V, 15V, or 20V.
18. A switching power supply comprising a control device according to any one of claims 1 to 17.
19. A control method applied to a flyback converter with variable output voltage, the flyback converter comprising an auxiliary switch, the control method comprising:
(a) detecting the output voltage of the flyback converter, and setting different on-time thresholds in different output voltage states in real time based on the output voltage and an excitation negative current reference value;
(b) and controlling the conduction of the auxiliary switch according to a control signal, and turning off the auxiliary switch when the conduction time of the auxiliary switch reaches the conduction time threshold value.
20. The control method of claim 19, wherein the flyback converter is an RCD clamped flyback converter or an active clamped flyback converter.
21. The control method of claim 19, wherein the auxiliary switch is a synchronous rectifier, a clamp, a switch connected in parallel to a secondary side rectifying unit of the flyback converter, or a switch connected in series to an auxiliary winding of the flyback converter.
22. The control method of claim 19, wherein said step (b) comprises: and outputting the control signal according to a timing starting signal.
23. The control method of claim 19, wherein the operating mode of the flyback converter is a discontinuous mode or a critical continuous mode.
24. The control method of claim 19, wherein the step (b) includes: starting a timer to time according to a timing starting signal to generate a timing signal; generating the control signal according to the timing signal.
25. The control method of claim 24, wherein the auxiliary switch is turned on according to the timing start signal.
26. The control method of claim 24, wherein the auxiliary switch is turned off when the timing signal is greater than or equal to the on-time threshold.
27. The control method of claim 24, wherein said step (b) further comprises: and resetting the timer according to a reset signal.
28. The control method according to claim 24, wherein in the discontinuous mode, the timing start signal is obtained by detecting an on signal of the auxiliary switch; and under a critical continuous mode, obtaining the timing starting signal by detecting the zero crossing point of the exciting negative current in the flyback converter.
29. The control method of claim 28, wherein the zero-crossing point of the excited negative current is detected by a current transformer, a sampling resistor, or an internal resistance of the auxiliary switch itself.
30. The control method of claim 27, wherein the reset signal is obtained by detecting an off signal of the auxiliary switch.
31. The control method of claim 19, wherein the step (a) includes: and calculating and obtaining the conduction time threshold value based on the output voltage and the exciting negative current reference value through division operation.
32. The control method according to claim 19, characterized by further comprising: (c) and after the auxiliary switch is turned off, realizing zero voltage switching-on of a primary side power switch tube of the flyback converter through resonance of an excitation inductor and a parasitic capacitor in the flyback converter.
33. The control method of claim 19, wherein said step (a) further comprises: and setting the exciting negative current reference value based on the input voltage of the flyback converter.
34. The control method of claim 33, wherein said step (a) further comprises: and setting the exciting negative current reference value based on the maximum value of the input voltage of the flyback converter.
35. The control method of claim 19, wherein said step (a) further comprises: and setting the exciting negative current reference value based on the input voltage of the flyback converter and the output voltage of the flyback converter.
36. The control method of claim 19, wherein the minimum magnitude of the negative excitation current is such that:
Figure FDA0003144866300000041
wherein: i ism_NFor exciting a negative current reference value, VbusFor input voltage, VOIs the output voltage, and n is the turns ratio of the transformer; l ismThe inductance is the excitation inductance; cEQIs the capacitance value of the parasitic capacitance.
37. The control method of claim 19, wherein the output voltage of the flyback converter is 5V, 9V, 15V, or 20V.
CN202110747537.4A 2017-04-10 2017-06-30 Control device and control method Active CN113595398B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202110747537.4A CN113595398B (en) 2017-04-10 2017-06-30 Control device and control method

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN201710229467 2017-04-10
CN2017102294677 2017-04-10
CN201710524232.0A CN108696132A (en) 2017-04-10 2017-06-30 control device and control method
CN202110747537.4A CN113595398B (en) 2017-04-10 2017-06-30 Control device and control method

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
CN201710524232.0A Division CN108696132A (en) 2017-04-10 2017-06-30 control device and control method

Publications (2)

Publication Number Publication Date
CN113595398A true CN113595398A (en) 2021-11-02
CN113595398B CN113595398B (en) 2024-02-02

Family

ID=63843935

Family Applications (2)

Application Number Title Priority Date Filing Date
CN201710524232.0A Pending CN108696132A (en) 2017-04-10 2017-06-30 control device and control method
CN202110747537.4A Active CN113595398B (en) 2017-04-10 2017-06-30 Control device and control method

Family Applications Before (1)

Application Number Title Priority Date Filing Date
CN201710524232.0A Pending CN108696132A (en) 2017-04-10 2017-06-30 control device and control method

Country Status (2)

Country Link
CN (2) CN108696132A (en)
TW (1) TWI653810B (en)

Families Citing this family (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110798075B (en) * 2019-11-08 2021-04-02 矽力杰半导体技术(杭州)有限公司 Control circuit and switching converter using same
CN110896271B (en) * 2019-11-08 2021-06-08 矽力杰半导体技术(杭州)有限公司 Zero-voltage switching-on control circuit and method and switching power supply applying same
CN111262444B (en) * 2020-02-20 2021-06-01 连云港杰瑞电子有限公司 Synchronous rectification control system and control method for secondary side resonance active clamping flyback
CN111525806B (en) * 2020-04-07 2021-02-26 浙江大学 AC-DC power conversion device
CN111953185B (en) * 2020-08-12 2021-07-13 安徽省东科半导体有限公司 ZVS (zero voltage switching) control method for active clamp flyback topology self-adaptive dead time
CN114400899B (en) * 2020-11-16 2023-07-18 上海百功半导体有限公司 Novel zero-voltage switching control circuit, method and voltage converter
CN113131748B (en) * 2021-03-16 2022-09-13 广州金升阳科技有限公司 Control method and control device of flyback converter
CN113054848B (en) * 2021-03-16 2022-07-19 广州金升阳科技有限公司 Control device and control method of flyback converter
CN113809920A (en) * 2021-08-19 2021-12-17 广州金升阳科技有限公司 BUCK converter control method
CN114301303A (en) * 2021-12-29 2022-04-08 上海安世博能源科技有限公司 Circuit control method and device

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102122890A (en) * 2010-10-11 2011-07-13 南京航空航天大学 Control method for auxiliary switching tube of active clamp flyback converter
TW201203833A (en) * 2010-01-28 2012-01-16 Sanyo Electric Co Driving control circuit for linear vibration motor
CN102723856A (en) * 2012-07-02 2012-10-10 矽力杰半导体技术(杭州)有限公司 Synchronous rectifier control circuit and switch power supply employing same
CN104539163A (en) * 2014-12-19 2015-04-22 广州金升阳科技有限公司 Synchronous rectification control method for flyback converter and control module of synchronous rectification control method
CN105226925A (en) * 2015-11-02 2016-01-06 南京航空航天大学 A kind of inverse-excitation type single-phase inverter and control method thereof
US20160233779A1 (en) * 2015-02-06 2016-08-11 Texas Instruments Incorporated Soft switching flyback converter

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW201203833A (en) * 2010-01-28 2012-01-16 Sanyo Electric Co Driving control circuit for linear vibration motor
CN102122890A (en) * 2010-10-11 2011-07-13 南京航空航天大学 Control method for auxiliary switching tube of active clamp flyback converter
CN102723856A (en) * 2012-07-02 2012-10-10 矽力杰半导体技术(杭州)有限公司 Synchronous rectifier control circuit and switch power supply employing same
CN104539163A (en) * 2014-12-19 2015-04-22 广州金升阳科技有限公司 Synchronous rectification control method for flyback converter and control module of synchronous rectification control method
US20160233779A1 (en) * 2015-02-06 2016-08-11 Texas Instruments Incorporated Soft switching flyback converter
CN105226925A (en) * 2015-11-02 2016-01-06 南京航空航天大学 A kind of inverse-excitation type single-phase inverter and control method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
MICHAEL T. ZHANG等: "design considerations and performance evaluations of synchronous rectification in flyback converters", 《IEEE》 *

Also Published As

Publication number Publication date
TWI653810B (en) 2019-03-11
CN113595398B (en) 2024-02-02
TW201838303A (en) 2018-10-16
CN108696132A (en) 2018-10-23

Similar Documents

Publication Publication Date Title
CN113595398B (en) Control device and control method
US10333417B2 (en) Device and method for controlling flyback converter
US10333418B2 (en) Control device and control method
US10291136B2 (en) Control device and control method
US8625311B2 (en) Switching power supply apparatus including a plurality of switching elements
TWI664801B (en) Switching power, control apparatus and control method
US7965523B2 (en) Switching power supply device
CN113726165B (en) Flyback converter and control method thereof
CN110798075B (en) Control circuit and switching converter using same
JP2005278263A (en) Switching power unit
CN113937988B (en) Asymmetric half-bridge flyback converter and control method thereof
CN111953185A (en) ZVS (zero voltage switching) control method for active clamp flyback topology self-adaptive dead time
CN113726166B (en) Flyback converter and control method thereof
CN111953186A (en) Switching power supply control circuit
KR20130019741A (en) Switch control circuit, power factor corrector comprising the same, and driving mehtod of the power factor corrector
JP3626072B2 (en) Switching power supply
JP2004364433A (en) Dc voltage conversion circuit
TWI650927B (en) Zero voltage switching flyback converter for primary switch turn-off transitions
JP4506469B2 (en) Resonant power supply
CN108696133B (en) Control device and control method
KR20160011497A (en) High-efficiency single-stage ac/dc converter for power factor correction
TWI653813B (en) Forced zero voltage switching flyback converter and using method
CN114614674A (en) Flyback converter, constant current control method and lighting system
JP2002374672A (en) Switching power source apparatus
JP5288491B2 (en) Switching power supply

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
GR01 Patent grant
GR01 Patent grant