TWI664801B - Switching power, control apparatus and control method - Google Patents
Switching power, control apparatus and control method Download PDFInfo
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- TWI664801B TWI664801B TW106127166A TW106127166A TWI664801B TW I664801 B TWI664801 B TW I664801B TW 106127166 A TW106127166 A TW 106127166A TW 106127166 A TW106127166 A TW 106127166A TW I664801 B TWI664801 B TW I664801B
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- 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
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Dc-Dc Converters (AREA)
Abstract
本案係關於一種控制裝置及控制方法,應用於返馳式變換器,返馳式變換器包含輔助開關,該控制裝置包括:輸出電壓積分單元,用於通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值;以及比較控制單元,用於將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,並根據比較結果控制輔助開關的關斷。本案能夠實現返馳式變換器的初級側開關管在不同輸出電壓下的零電壓開通。 This case relates to a control device and a control method, which are applied to a flyback converter. The flyback converter includes an auxiliary switch. The control device includes: an output voltage integration unit for performing an output voltage on the flyback converter. Integrate to obtain the magnitude of the negative magnetizing current in the flyback converter; and a comparison control unit for comparing the obtained magnitude of the negative magnetizing current with a reference value of the negative magnetizing current, and control the auxiliary switch according to the comparison result Off. This case can realize the zero-voltage turn-on of the primary-side switch of the flyback converter under different output voltages.
Description
本案係關於電力電子技術領域,尤指一種應用於返馳式變換器的控制裝置及控制方法。 This case relates to the field of power electronics technology, in particular to a control device and control method applied to a flyback converter.
目前,準諧振返馳式變換器是應用於小功率開關電源的最流行的電路拓撲結構。準諧振返馳式變換器在低壓輸入(Vbus<nVo,其中:Vbus為輸入電壓;n為變壓器初次級側線圈匝數比;Vo為輸出電壓)時可以實現初級側功率開關管的零電壓開通(ZVS),在高壓輸入(Vbus>nVo)時可以實現初級側功率開關管的谷底開通,因而可以顯著減小開關損耗。然而,隨著高頻化發展,儘管準諧振返馳式變換器在高壓輸入時可以實現谷底開通,但開通損耗還是變得越來越大,嚴重影響變換器的效率。為了解決準諧振返馳式變換器在高壓輸入時不能完全實現初級側功率開關管的零電壓開通(ZVS)這個問題,習知技術提出了次級側同步整流管延遲導通等新控制方法,以及有源鉗位返馳式變換器等新電路拓撲結構。 At present, quasi-resonant flyback converters are the most popular circuit topology applied to small power switching power supplies. The quasi-resonant flyback converter can realize the primary-side power switch when the low-voltage input (V bus <nV o , where: V bus is the input voltage; n is the turns ratio of the primary winding of the transformer; V o is the output voltage) The zero-voltage turn-on (ZVS) can achieve valley turn-on of the primary-side power switch at high-voltage input (V bus > nV o ), so the switching loss can be significantly reduced. However, with the development of high frequency, although the quasi-resonant flyback converter can achieve valley turn-on at high voltage input, the turn-on loss has become larger and larger, which seriously affects the efficiency of the converter. In order to solve the problem that the quasi-resonant flyback converter cannot fully realize the zero-voltage turn-on (ZVS) of the primary-side power switch at the high-voltage input, the conventional technology proposes new control methods such as the delayed conduction of the secondary-side synchronous rectifier and New circuit topologies such as active clamp flyback converters.
然而,習知技術僅適用于輸出電壓恒定的情況,在可變輸出電壓的應用情況下無法保證所有工作條件下均能實現初級側功率開關管的零電壓開通。 However, the conventional technology is only applicable to a case where the output voltage is constant, and in the case of a variable output voltage application, it cannot guarantee that the zero-voltage turn-on of the primary-side power switch can be achieved under all operating conditions.
因此,如何發展一種可改善上述習知技術缺失之控制裝置及控制方法,實為目前迫切之需求。 Therefore, how to develop a control device and a control method that can improve the lack of the conventional technology is an urgent need at present.
本案之目的在於提供一種控制裝置及控制方法,進而至少在一定程度上克服由於相關技術的限制和缺陷而導致的一個或者多個問題。 The purpose of this case is to provide a control device and a control method, so as to at least to some extent overcome one or more problems caused by the limitations and defects of the related technology.
本案之一實施態樣提供了一種控制裝置,應用於返馳式變換器,返馳式變換器包含輔助開關,控制裝置包括:輸出電壓積分單元,用於通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值;以及比較控制單元,用於將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,並根據比較結果控制輔助開關的關斷。 An embodiment of the present invention provides a control device applied to a flyback converter. The flyback converter includes an auxiliary switch. The control device includes: an output voltage integration unit for passing the output voltage of the flyback converter. Perform integration to obtain the magnitude of the negative excitation current in the flyback converter; and a comparison control unit for comparing the obtained magnitude of the negative excitation current with a reference value of the negative excitation current, and control the auxiliary according to the comparison result Switch off.
其中,輔助開關為同步整流管、鉗位管、並聯在返馳式變換器的次級側整流單元上的開關、或串聯於返馳式變換器的輔助繞組的開關。 Among them, the auxiliary switch is a synchronous rectifier tube, a clamp tube, a switch connected in parallel on the secondary side rectifier unit of the flyback converter, or a switch connected in series with the auxiliary winding of the flyback converter.
其中,返馳式變換器的工作模式為斷續模式或臨界連續模式。 Among them, the working mode of the flyback converter is discontinuous mode or critical continuous mode.
其中,對返馳式變換器的輸出電壓進行積分包括:通過使能信號啟動輸出電壓積分單元,以及通過復位信號對輸出電壓積分單元進行復位。 Wherein, integrating the output voltage of the flyback converter includes: starting the output voltage integration unit through an enable signal, and resetting the output voltage integration unit through a reset signal.
其中,在斷續模式下,通過檢測輔助開關的開通信號得到使能信號;以及在臨界連續模式下,通過檢測激磁負電流的過零點得到使能信號。 Among them, in the discontinuous mode, an enable signal is obtained by detecting the opening signal of the auxiliary switch; and in the critical continuous mode, the enable signal is obtained by detecting the zero-crossing point of the negative excitation current.
其中,檢測激磁負電流的過零點包括:通過電流互感器、取樣電阻或者輔助開關的自身內阻來檢測激磁負電流的過零點。 Among them, detecting the zero-crossing point of the negative excitation current includes: detecting the zero-crossing point of the negative excitation current through a current transformer, a sampling resistor, or the internal resistance of the auxiliary switch.
其中,通過檢測輔助開關的關斷信號得到復位信號。 The reset signal is obtained by detecting the off signal of the auxiliary switch.
其中,比較控制單元用以於激磁負電流的幅值大於或等於激磁負電流基準值時,控制輔助開關的關斷。 The comparison control unit is configured to control the auxiliary switch to be turned off when the amplitude of the negative excitation current is greater than or equal to the reference value of the negative excitation current.
其中,返馳式變換器為RCD鉗位返馳式變換器或有源鉗位返馳式變換器。 Among them, the flyback converter is an RCD clamp flyback converter or an active clamp flyback converter.
其中,控制裝置還包括:第一激磁負電流基準設定單元,用於基於返馳式變換器的輸入電壓設定激磁負電流基準值。 The control device further includes: a first excitation negative current reference setting unit, configured to set a reference value of the excitation negative current based on the input voltage of the flyback converter.
其中,控制裝置還包括:第二激磁負電流基準設定單元,用於基於返馳式變換器的輸入電壓和輸出電壓設定激磁負電流基準值。 The control device further includes a second excitation negative current reference setting unit for setting a reference value of the excitation negative current based on the input voltage and the output voltage of the flyback converter.
其中,返馳式變換器的輸出電壓可變。 Among them, the output voltage of the flyback converter is variable.
其中,返馳式變換器的輸出電壓為5V、9V、15V或20V。 Among them, the output voltage of the flyback converter is 5V, 9V, 15V or 20V.
本案之另一實施態樣提供了一種開關電源,包括根據上述任意一項所述的控制裝置。 Another aspect of the present invention provides a switching power supply, including the control device according to any one of the above.
本案之再一實施態樣提供一種控制方法,應用於返馳式變換器,返馳式變換器包含輔助開關,控制方法包括:通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值; 將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較;以及根據比較結果控制輔助開關的關斷以實現返馳式變換器的初級側功率開關管的零電壓開通。 Another implementation aspect of the present case provides a control method applied to a flyback converter. The flyback converter includes an auxiliary switch. The control method includes: integrating the output voltage of the flyback converter to obtain a flyback converter. The magnitude of the negative excitation current in the converter; The obtained amplitude of the negative excitation current is compared with a reference value of the negative excitation current; and the auxiliary switch is controlled to be turned off according to the comparison result to realize the zero-voltage turn-on of the primary-side power switch of the flyback converter.
其中,輔助開關為同步整流管、鉗位管、並聯在返馳式變換器的次級側整流單元上的開關、或串聯於返馳式變換器的輔助繞組的開關。 Among them, the auxiliary switch is a synchronous rectifier tube, a clamp tube, a switch connected in parallel on the secondary side rectifier unit of the flyback converter, or a switch connected in series with the auxiliary winding of the flyback converter.
其中,返馳式變換器的工作模式為斷續模式或臨界連續模式。 Among them, the working mode of the flyback converter is discontinuous mode or critical continuous mode.
其中,對返馳式變換器的輸出電壓進行積分包括:響應於使能信號通過積分線路開始對返馳式變換器的輸出電壓進行積分,以及響應於復位信號對積分線路進行復位。 Wherein, integrating the output voltage of the flyback converter includes: starting to integrate the output voltage of the flyback converter through an integration line in response to an enable signal, and resetting the integration line in response to a reset signal.
其中,在斷續模式下,通過檢測輔助開關的開通信號得到使能信號;以及在臨界連續模式下,通過檢測激磁負電流的過零點得到使能信號。 Among them, in the discontinuous mode, an enable signal is obtained by detecting the opening signal of the auxiliary switch; and in the critical continuous mode, the enable signal is obtained by detecting the zero-crossing point of the negative excitation current.
其中,通過電流互感器、取樣電阻或者輔助開關的自身內阻來檢測激磁負電流的過零點。 Among them, the zero crossing of the negative excitation current is detected by the current transformer, the sampling resistor or the internal resistance of the auxiliary switch.
其中,通過輔助開關的關斷信號得到復位信號。 The reset signal is obtained by the off signal of the auxiliary switch.
其中,實現返馳式變換器的初級側功率開關管的零電壓開通包括:通過返馳式變換器中的激磁電感與寄生電容的諧振來實現返馳式變換器的初級側功率開關管的零電壓開通。 Among them, implementing the zero-voltage turn-on of the primary-side power switch of the flyback converter includes: realizing zero of the primary-side power switch of the flyback converter through the resonance of the excitation inductance and parasitic capacitance in the flyback converter Voltage is on.
其中,根據比較結果控制輔助開關的關斷來實現返馳式變換器的初級側功率開關管的零電壓開通還包含: 於激磁負電流的幅值大於或等於激磁負電流基準值時,控制輔助開關的關斷。 Among them, controlling the turning off of the auxiliary switch according to the comparison result to realize the zero-voltage turning on of the primary-side power switch of the flyback converter further includes: When the amplitude of the negative excitation current is greater than or equal to the reference value of the negative excitation current, the auxiliary switch is controlled to be turned off.
其中,返馳式變換器為RCD鉗位返馳式變換器或有源鉗位返馳式變換器。 Among them, the flyback converter is an RCD clamp flyback converter or an active clamp flyback converter.
其中,控制方法還包括:基於返馳式變換器的輸入電壓設定激磁負電流基準值。 The control method further includes: setting a reference value of the exciting negative current based on the input voltage of the flyback converter.
其中,基於返馳式變換器的輸入電壓設定激磁負電流基準值包括:基於返馳式變換器的輸入電壓的最大值設定激磁負電流基準值。 Wherein, setting the reference value of the exciting negative current based on the input voltage of the flyback converter includes: setting the reference value of the exciting negative current based on the maximum value of the input voltage of the flyback converter.
其中,控制方法還包括:基於返馳式變換器的輸入電壓和輸出電壓設定激磁負電流基準值。 The control method further includes: setting a reference value of the exciting negative current based on an input voltage and an output voltage of the flyback converter.
其中,返馳式變換器的輸出電壓可變。 Among them, the output voltage of the flyback converter is variable.
其中,返馳式變換器的輸出電壓為5V、9V、15V或20V。 Among them, the output voltage of the flyback converter is 5V, 9V, 15V or 20V.
根據本案實施態樣之控制裝置及控制方法,通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值,將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,根據比較結果控制輔助開關的關斷。一方面,通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值,可以實時地獲得不同輸出電壓下的激磁負電流的幅值;另一方面,將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,根據比較結果控制輔助開關的關斷,可以通過合理地設定激磁負電流基準值來實現初級側開關管在不同輸出電壓下的零電壓開通。 According to the control device and control method of the present embodiment, the amplitude of the negative excitation current in the flyback converter is obtained by integrating the output voltage of the flyback converter, and the amplitude of the obtained negative excitation current is obtained. Compare it with the reference value of the excitation negative current, and control the turning off of the auxiliary switch according to the comparison result. On the one hand, by integrating the output voltage of the flyback converter to obtain the amplitude of the negative excitation current in the flyback converter, the amplitude of the negative excitation current under different output voltages can be obtained in real time; , Comparing the amplitude of the obtained negative excitation current with the reference value of the negative excitation current, and controlling the turn-off of the auxiliary switch according to the comparison result, the primary-side switch tube at different output voltages can be achieved by rationally setting the reference value of the negative excitation current Turn on at zero voltage.
應當理解的是,以上的一般描述和後文的細節描述僅是示例性和解釋性的,並不能限制本案。 It should be understood that the above general description and the following detailed description are merely exemplary and explanatory, and should not limit the case.
S1‧‧‧開關管 S 1 ‧‧‧ Switch tube
S2‧‧‧鉗位管 S 2 ‧‧‧Clamp
t、t0、t1、t2、t3、t4、t5‧‧‧時刻 t, t 0 , t 1 , t 2 , t 3 , t 4 , t 5 ‧‧‧ time
SR‧‧‧同步整流管 S R ‧‧‧Synchronous Rectifier
Lm‧‧‧激磁電感 L m ‧‧‧ Excitation inductance
Im_n‧‧‧激磁負電流 I m_n ‧‧‧Negative excitation current
n‧‧‧匝數比 n‧‧‧turn ratio
Vo‧‧‧輸出電壓 V o ‧‧‧ output voltage
Im_n(t)‧‧‧激磁負電流的幅值 I m_n (t) ‧‧‧ amplitude of negative excitation current
600、1100、1200、1300、1400‧‧‧控制裝置 600, 1100, 1200, 1300, 1400‧‧‧ control devices
610、1110、1210‧‧‧返馳式變換器 610, 1110, 1210‧‧‧ Flyback Converter
620、1120、1220、1320、1420‧‧‧輸出電壓積分單元 620, 1120, 1220, 1320, 1420‧‧‧‧ output voltage integration unit
630、1130、1230、1330、1430‧‧‧比較控制單元 630, 1130, 1230, 1330, 1430‧‧‧‧Comparison control unit
640、1140、1240、1340、1440‧‧‧激磁負電流基準設定單元 640, 1140, 1240, 1340, 1440‧‧‧ Excitation negative current reference setting unit
1360、1460‧‧‧輸入電壓檢測單元 1360, 1460‧‧‧ input voltage detection unit
Im_N‧‧‧基準值 I m_N ‧‧‧ reference value
CEQ‧‧‧寄生電容 C EQ ‧‧‧ Parasitic capacitance
T‧‧‧變壓器 T‧‧‧Transformer
D1‧‧‧二極管 D1‧‧‧Diode
Saux、Saux_VCC‧‧‧開關 S aux , S aux_VCC ‧‧‧ switch
Waux‧‧‧輔助繞組 W aux ‧‧‧ auxiliary winding
R1、R2、R3、R4、Rsense‧‧‧電阻 R 1 , R 2 , R 3 , R 4 , R sense ‧‧‧ resistance
Isense‧‧‧電流信號 I sense ‧‧‧ current signal
Csense‧‧‧電容 C sense ‧‧‧ capacitor
Vsense‧‧‧電壓積分信號 V sense ‧‧‧Voltage integral signal
Co‧‧‧輸出電容 C o ‧‧‧ output capacitor
Vbus‧‧‧輸入電壓 V bus ‧‧‧ input voltage
Vbus_max‧‧‧輸入電壓最大值 Vb us_max ‧‧‧ Maximum input voltage
S1510、S1520、S1530‧‧‧步驟 S1510, S1520, S1530‧‧‧ steps
第1圖係為一種技術方案中的有源鉗位返馳式變換器的電路圖;第2圖係為一種技術方案中的有源鉗位返馳式變換器的斷續模式控制波形圖;第3圖係為一種技術方案中的RCD鉗位返馳式變換器的電路圖;第4圖係為一種技術方案中的RCD鉗位返馳式變換器的臨界連續模式控制波形圖;第5圖係為另一種技術方案中的RCD鉗位返馳式變換器的電路圖;第6圖係為本案一較佳實施例的控制裝置的控制原理示意圖;第7圖係為本案另一較佳實施例的控制裝置的控制原理示意圖;第8圖係為本案又一較佳實施例的電壓積分電路圖;第9圖係為本案再一較佳實施例的RCD鉗位返馳式變換器的斷續模式控制波形圖;第10圖係為本案又一較佳實施例的有源鉗位返馳式變換器的臨界連續模式控制波形圖;第11圖係為本案又一較佳實施例的RCD鉗位返馳式變換器的電壓積分檢測控制法的一個具體實施例;第12圖係為本案又一較佳實施例的有源鉗位返馳式變換器的導通時間檢測控制法的一個具體實施例; 第13圖係為本案又一較佳實施例的RCD鉗位返馳式變換器的基準值隨輸入電壓變化的設定方法的一個具體實施例。 Figure 1 is a circuit diagram of an active clamp flyback converter in a technical scheme; Figure 2 is a discontinuous mode control waveform diagram of an active clamp flyback converter in a technical scheme; Figure 3 is a circuit diagram of an RCD clamped flyback converter in a technical scheme; Figure 4 is a critical continuous mode control waveform diagram of an RCD clamped flyback converter in a technical scheme; Figure 5 is FIG. 6 is a circuit diagram of an RCD clamp flyback converter in another technical solution; FIG. 6 is a schematic diagram of a control principle of a control device of a preferred embodiment of the present invention; FIG. 7 is a schematic diagram of another preferred embodiment of the present invention. Schematic diagram of the control principle of the control device; Figure 8 is a voltage integration circuit diagram of another preferred embodiment of the present invention; Figure 9 is a discontinuous mode control of an RCD clamp flyback converter according to another preferred embodiment of the present invention Waveform diagram; FIG. 10 is a critical continuous mode control waveform diagram of an active clamp flyback converter according to another preferred embodiment of the present invention; and FIG. 11 is an RCD clamp return of another preferred embodiment of the present invention. A Method of Voltage Integral Detection and Control for Gallo Converter Specific embodiment; FIG. 12 is a specific embodiment of an on-time detection and control method of an active clamp flyback converter according to another preferred embodiment of the present invention; FIG. 13 is a specific embodiment of a method for setting a reference value of an RCD clamp flyback converter with input voltage according to another preferred embodiment of the present invention.
第14圖係為本案又一較佳實施例的有源鉗位返馳式變換器的基準值隨輸入電壓變化的設定方法的一個具體實施例;以及第15圖係為本案又一較佳實施例的控制方法的流程圖。 FIG. 14 is a specific embodiment of a method for setting a reference value of an active clamp flyback converter according to an input voltage according to another preferred embodiment of the present invention; and FIG. 15 is another preferred implementation of the present invention. Example control method flowchart.
體現本案特徵與優點的典型實施例將在後段的說明中結合圖式詳細敘述。應理解的是本案能夠在不同的態樣上具有各種的變化,其皆不脫離本案的範圍,且其中的說明及圖式在本質上當作說明之用,而非架構於限制本案。 A typical embodiment embodying the features and advantages of this case will be described in detail in the following paragraphs with reference to the drawings. It should be understood that the present case can have various changes in different aspects, all of which do not depart from the scope of the present case, and that the descriptions and drawings therein are essentially for the purpose of illustration, rather than limiting the case.
此外,本案圖式僅為示意圖,並非一定是按比例繪製。圖式中相同的註記表示相同或類似的部分,因而將省略對其重複描述。圖式中所示的一些方框圖是功能實體,不一定必須與物理或邏輯上獨立的實體相對應。可以運用軟體來實現這些功能實體,或在一個或多個硬體模組或積體電路中實現這些功能實體,或在不同網絡和/或處理器裝置和/或微控制器裝置中實現這些功能實體。 In addition, the drawings in this case are only schematic diagrams and are not necessarily drawn to scale. The same notes in the drawings represent the same or similar parts, and thus repeated descriptions thereof will be omitted. Some block diagrams shown in the figures are functional entities and do not necessarily have to correspond to physically or logically independent entities. Software can be used to implement these functional entities, or to implement these functional entities in one or more hardware modules or integrated circuits, or to implement these functions in different networks and / or processor devices and / or microcontroller devices entity.
第1圖係為一種技術方案中的有源鉗位返馳式變換器的電路圖。有源鉗位返馳式變換器可以實現初級側功率開關管S1的零電壓開通(ZVS),習知的控制方法為:控制鉗位管S2僅在初級側功率開關管S1導通前導通一設定時間,如第2圖所示的控制波形圖中的t2-t3。 Figure 1 is a circuit diagram of an active clamp flyback converter in a technical solution. The active clamp flyback converter can achieve zero voltage turn-on (ZVS) of the primary-side power switch S 1. The conventional control method is: control the clamp S 2 only before the primary-side power switch S 1 is turned on. Turn on for a set time, as shown by t2-t3 in the control waveform diagram shown in Figure 2.
第3圖示出了一種技術方案中的RCD鉗位返馳式變換器的電路圖。RCD鉗位返馳式變換器通過延遲導通準諧振返馳式變換器的 次級側同步整流管SR來實現初級側功率開關管S1的零電壓開通(ZVS),習知的次級側同步整流管SR的延遲導通控制方法為:控制同步整流管SR在次級側電流is降到零之後繼續導通一設定時間,如第4圖所示的控制波形圖中的t1-t2。 FIG. 3 shows a circuit diagram of an RCD clamp flyback converter in a technical solution. RCD clamp flyback converter resonant flyback converter by delaying the conduction of the secondary-side synchronous rectifier quasi S R to the primary side power switch to achieve ZVS S 1 (ZVS), conventional secondary side conduction delay control method of the synchronous rectifier is S R: S R synchronous rectifier control after the secondary-side current i s turned to zero continues for a set time, the control waveform diagram as shown in FIG. 4 of t1-t2 .
以上兩種實現初級側功率開關管S1零電壓開通(ZVS)的方法,都是通過控制同步整流管SR或鉗位管S2開通一設定時間來實現的,這對於固定輸出電壓的應用情形是適用的。 The above two methods for realizing the zero-voltage turn-on (ZVS) of the primary-side power switch S 1 are achieved by controlling the synchronous rectifier S R or the clamp S 2 to be turned on for a set time. This is for the application of fixed output voltage The situation is applicable.
然而,隨著電源供應器的發展,尤其是USB-PD Type-C的推廣和普及,可變輸出電壓的應用變得越來越流行。對於可變輸出電壓的應用情形,上述控制方式將不再適用,這是因為:無論是RCD鉗位返馳式變換器,還是有源鉗位返馳式變換器,其實現初級側功率開關管零電壓開通(ZVS)的基本原理如下:在初級側功率開關管S1開通之前,使得變壓器的激磁電感Lm上產生一激磁負電流Im_n,通過激磁負電流Im_n的幫助以實現初級側功率開關管S1的零電壓開通(ZVS),且激磁負電流的大小由如下公式決定:
其中:Lm是變壓器的激磁電感值,n是變壓器的匝數比,Vo是變換器的輸出電壓值,Im_n(t)是激磁負電流的幅值,t是輔助開關的導通時間(對於準諧振返馳式變換器的同步整流管來說指的是延遲導通時間,對於有源鉗位返馳式變換器的鉗位管來說指的是導通時間)。 Among them: L m is the excitation inductance value of the transformer, n is the turns ratio of the transformer, V o is the output voltage value of the converter, I m_n (t) is the amplitude of the negative excitation current, and t is the on-time of the auxiliary switch ( (For synchronous rectifiers of quasi-resonant flyback converters, it refers to delayed on-time, and for active-clamp flyback converters, it refers to on-time).
由上述公式可以看出,對於一個固定的設計,激磁電感值Lm和匝數比n是固定的。如果輸出電壓Vo是固定的,由公式(1)可知, 固定的導通時間t意味著固定的激磁負電流幅值,因此,通過控制同步整流管SR或鉗位管S2開通一設定時間t,對於固定輸出電壓的應用情形是適用的。如果輸出電壓是可變的,固定的導通時間意味著激磁負電流幅值會隨輸出電壓的變化而改變。以USB-PD Type-C的應用為例,其最小輸出電壓為5V,最大輸出電壓為20V,如果採用固定導通時間的控制方法,會造成以下兩個結果中的一個: It can be seen from the above formula that for a fixed design, the excitation inductance value L m and the turns ratio n are fixed. If the output voltage Vo is fixed, it can be known from the formula (1) that the fixed on-time t means a fixed negative amplitude of the exciting current. Therefore, by controlling the synchronous rectifier tube S R or the clamp tube S 2 to be turned on for a set time t It is suitable for the application of fixed output voltage. If the output voltage is variable, a fixed on-time means that the magnitude of the negative magnetizing current will change as the output voltage changes. 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 a fixed on-time control method is used, it will cause one of the following two results:
A:如果設定的導通時間恰好可以滿足輸出電壓為5V時的初級側功率開關管零電壓開通(ZVS)的條件,那麼當輸出電壓為20V時,產生的激磁負電流幅值將是輸出電壓為5V時的4倍。過大的激磁負電流會引入額外損耗,影響變換器的效率。 A: If the set on-time exactly meets the condition of zero-voltage turn-on (ZVS) of the primary-side power switch when the output voltage is 5V, then when the output voltage is 20V, the amplitude of the negative excitation current generated will be 4 times at 5V. Excessive negative excitation current will introduce additional losses and affect the efficiency of the converter.
B:如果設定的導通時間恰好可以滿足輸出電壓為20V時的初級側功率開關管零電壓開通(ZVS)的條件,那麼當輸出電壓為5V時,產生的激磁負電流幅值將只有輸出電壓為20V時的1/4,過小的激磁負電流幅值會造成初級側功率開關管不能實現零電壓開通。 B: If the set on-time exactly meets the condition of zero-voltage turn-on (ZVS) of the primary-side power switch when the output voltage is 20V, then when the output voltage is 5V, the amplitude of the negative excitation current generated will be 1/4 at 20V, too small excitation negative current amplitude will cause the primary-side power switch to achieve zero voltage turn-on.
基於上述內容,在本案之一較佳實施例中,首先提供了一種控制裝置,控制裝置600用於控制返馳式變換器610,其中返馳式變換器610包含一輔助開關。如第6圖所示,該控制裝置600可以包括:輸出電壓積分單元620以及比較控制單元630。其中:輸出電壓積分單元620用於通過對返馳式變換器610的輸出電壓進行積分來獲得返馳式變換器610中的激磁負電流的幅值;以及比較控制單元630用於將所獲得的激磁負電流的幅值與一激磁負電流基準值進行比較,並根據比較結果控制輔助開關的關斷。 Based on the above, in a preferred embodiment of the present case, a control device is first provided. The control device 600 is used to control a flyback converter 610, where the flyback converter 610 includes an auxiliary switch. As shown in FIG. 6, the control device 600 may include an output voltage integration unit 620 and a comparison control unit 630. Wherein: the output voltage integration unit 620 is configured to obtain the amplitude of the exciting negative current in the flyback converter 610 by integrating the output voltage of the flyback converter 610; and the comparison control unit 630 is configured to use the obtained The amplitude of the negative excitation current is compared with a reference value of the negative excitation current, and the auxiliary switch is turned off according to the comparison result.
根據此實施例的控制裝置600,一方面,通過對返馳式變換器610的輸出電壓進行積分來獲得返馳式變換器610中的激磁負電流的幅值,可以實時地獲得不同輸出電壓下的激磁負電流的幅值;另一方面,將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,根據比較結果控制輔助開關的關斷,可以通過合理地設定激磁負電流基準值來實現初級側開關管在不同輸出電壓下的零電壓開通。 According to the control device 600 of this embodiment, on the one hand, by integrating the output voltage of the flyback converter 610 to obtain the magnitude of the exciting negative current in the flyback converter 610, it is possible to obtain different output voltages in real time. On the other hand, the obtained amplitude of the negative excitation current is compared with the reference value of the negative excitation current, and the turn-off of the auxiliary switch is controlled according to the comparison result. The reasonable value of the negative excitation current reference can be set. Value to achieve zero-voltage turn-on of the primary-side switch at different output voltages.
在此實施例中,返馳式變換器610還包括初級側開關單元、次級側整流單元、變壓器和輸出電容(未圖示),其中,初級側開關單元包含初級側功率開關管,次級側整流單元包括第一端與第二端,第一端和第二端分別與變壓器和輸出電容電氣連接。為適用可變輸出電壓的應用情形,實現全輸入電壓範圍內(例如90~264Vac),不同輸出電壓下的全負載範圍內的初級側功率開關管的零電壓開通(ZVS),需要控制激磁負電流的幅值達一設定值。根據以下公式(2):
可知,通過檢測輸出電壓Vo和時間t的乘積即可間接檢測激磁負電流的幅值,而輸出電壓Vo和時間t的乘積的物理意義是輸出電壓Vo對時間t進行積分。因此,本案的基本原理在於:在初級側功率開關管開通之前,通過控制輔助開關的開通和關斷,使得返馳式變換器610中產生一激磁負電流。通過檢測輸出電壓,並對輸出電壓進行積分控制,以得到激磁負電流幅值的信息Im_n(t)。設定激磁負電流的基準值Im_N,當激磁負電流的幅值大於或等於該 基準值時,比較控制單元630輸出控制信號用以關斷輔助開關。 然後,以此激磁負電流為初始值,通過激磁電感Lm與原邊線路的寄生電容CEQ的諧振來實現初級側功率開關管的零電壓開通(ZVS)。通過合理設置激磁負電流的基準值,可在全輸入電壓範圍,不同輸出電壓的全負載範圍內實現初級側功率開關管的零電壓開通(ZVS)。於本實施例中,該寄生電容CEQ由初級側功率開關管S1的寄生電容和變壓器T的初級側線圈的寄生電容構成。 Understood, a product by detecting the output voltage V o and time t can be indirectly detected amplitude of the exciting current is negative, and the physical meaning of the output voltage V o and the time t is the product of the output voltage Vo is integrated over time t. Therefore, the basic principle of this case is that before the primary-side power switch is turned on, by controlling the on and off of the auxiliary switch, a negative magnetic current is generated in the flyback converter 610. By detecting the output voltage and performing integral control on the output voltage, information I m_n (t) of the magnitude of the negative excitation current is obtained. A reference value I m_N of the negative excitation current is set. When the amplitude of the negative excitation current is greater than or equal to the reference value, the comparison control unit 630 outputs a control signal to turn off the auxiliary switch. Then, based on the excitation negative current as the initial value, the zero-voltage turn-on (ZVS) of the primary-side power switch is achieved through the resonance of the excitation inductance L m and the parasitic capacitance C EQ of the primary line. By properly setting the reference value of the negative excitation current, the zero-voltage turn-on (ZVS) of the primary-side power switch can be realized in the full input voltage range and the full load range of different output voltages. In this embodiment, the parasitic capacitance C EQ is composed of the parasitic capacitance of the primary-side power switch S1 and the parasitic capacitance of the primary-side coil of the transformer T.
需要說明的是,在此實施例中,返馳式變換器610的輸出電壓可變,例如返馳式變換器610的輸出電壓可以為5V、9V、15V或20V等,本案對此不進行特殊限定。 It should be noted that, in this embodiment, the output voltage of the flyback converter 610 is variable. For example, the output voltage of the flyback converter 610 may be 5V, 9V, 15V, or 20V, etc., this case does not make any special limited.
此外,如第7圖所示,在本案之較佳實施例中,為了合理地設定激磁負電流基準值,控制裝置600還可以包括激磁負電流基準設定單元640,用於基於返馳式變換器610的輸入電壓或/和輸出電壓設定所述激磁負電流基準值。 In addition, as shown in FIG. 7, in a preferred embodiment of the present case, in order to reasonably set the reference value of the excitation negative current, the control device 600 may further include an excitation negative current reference setting unit 640 for use in a flyback-based converter. An input voltage or output voltage of 610 sets the reference value of the exciting negative current.
此外,在某些實施例中,返馳式變換器610可以為如第1圖所示的有源鉗位返馳式變換器或如第3圖和第5圖所示的RCD鉗位返馳式變換器,但是本案較佳實施例中的返馳式變換器不限於此。 In addition, in some embodiments, the flyback converter 610 may be an active clamp flyback converter as shown in FIG. 1 or an RCD clamp flyback as shown in FIGS. 3 and 5. Converter, but the flyback converter in the preferred embodiment of the present invention is not limited to this.
進一步地,在某些實施例中,返馳式變換器610的輔助開關可以為如第1圖所示的鉗位管S2或如第3圖所示的同步整流管SR,但是本案之較佳實施例中的輔助開關不限於此,例如如第5圖所示的副邊為二極管整流的RCD鉗位返馳式變換器,其輔助開關可以為並聯於二極管D1的開關Saux,或其輔助開關可以為串聯於輔助繞組Waux的開關Saux_VCC。需要說明的是,在本案較佳實施例中,控 制裝置600可以適用於不同的工作模式,包括斷續模式和臨界連續模式,本案對此不進行特殊限定。 Further, in some embodiments, the auxiliary switch of the flyback converter 610 may be a clamp tube S 2 as shown in FIG. 1 or a synchronous rectifier tube S R as shown in FIG. 3. The auxiliary switch in the preferred embodiment is not limited to this. For example, as shown in Fig. 5, the secondary side is a diode-rectified RCD clamp flyback converter. The auxiliary switch may be a switch S aux connected in parallel to the diode D1, or The auxiliary switch may be a switch S aux_VCC connected in series to the auxiliary winding W aux . It should be noted that, in the preferred embodiment of this case, the control device 600 may be applicable to different working modes, including discontinuous mode and critical continuous mode, which is not specifically limited in this case.
在本某些實施例中,電壓積分功能的實現可以有多種方式,例如可以採用數字電路,也可以採用模擬線路。在此以模擬線路舉例說明如下。如第8圖所示的電壓積分電路包含放大器和電阻R1-R4至Rsense,但不限於此。由電路原理可知,只要滿足下式:
亦即,R1=R2,R3=R4,即可得:
由於Rsense為已知固定值,因此公式(4)即將電壓信號Vo轉化為電流信號Isense。用電流信號Isense給一電容Csense充電,電容Csense上的電壓即體現為輸出電壓Vo的積分信號
可得:
由於Csense和Rsense是已知參數,因此通過檢測輸出電壓Vo即可得到輸出電壓積分信號Vsense。 Since C sense and R sense are known parameters, the output voltage integrated signal V sense can be obtained by detecting the output voltage V o .
第8圖係為本案又一較佳實施例的電壓積分電路圖。如第8圖所示:使能信號作用于開關管S1,且被設置為低電平有效:當使能信號為高電平時,開關管S1閉合,此時積分線路不工作;當使能信號為低電平時,開關管S1斷開,積分線路開始工作。復位信號作用于開關管S2,且被設置為高電平有效:當復位信號為低電平時,開關管S2斷開,電容Csense被充電,以檢測電壓積分信號Vsense,積分線路保持工作狀態;當復位信號為高電平時,開關管S2閉合,電容Csense被充分放電,此時電壓積分信號Vsense為0,積分線路復位,積分電路停止工作。於另一實施例中,積分信號的有效電平信號亦可為高電平,復位信號的有效電平信號亦可為低電平,在此不做限制。於另一實施例中,亦可不必設置開關管S1和使能信號,同樣可控制積分線路的工作狀態。 FIG. 8 is a voltage integration circuit diagram of another preferred embodiment of the present invention. As shown in Figure 8: the enable signal acts on the switch S 1 and is set to be active low: when the enable signal is high, the switch S 1 is closed, and the integration line does not work at this time; When the energy signal is at a low level, the switch S 1 is turned off, and the integration line starts to work. The reset signal acts on the switch S 2 and is set to be active high: when the reset signal is low, the switch S 2 is turned off and the capacitor C sense is charged to detect the voltage integration signal V sense and the integration line remains Working state; when the reset signal is high, the switch S 2 is closed and the capacitor C sense is fully discharged. At this time, the voltage integration signal V sense is 0, the integration line is reset, and the integration circuit stops working. In another embodiment, the effective level signal of the integration signal may also be a high level, and the effective level signal of the reset signal may also be a low level, which is not limited herein. In another embodiment, it is not necessary to set the switch S1 and the enable signal, and the working state of the integration circuit can also be controlled.
需要說明的是,在某些實施例中,對於斷續工作模式來說,積分單元的使能信號可以通過輔助開關的開通信號來獲得。如第2圖所示,在t2時刻S2驅動信號的上升沿跳變信號為輔助開關的開通信號,如第9圖所示,在t2時刻的SR驅動信號的上升沿跳變信號為輔助開關的開通信號,可以通過檢測這個上升沿跳變信號來得到使能信號。需要說明的是,使能信號也可以和這個上升沿跳變信號同步,也可以是由該上升沿跳變信號做一定延遲得到。 It should be noted that, in some embodiments, for the intermittent operation mode, the enable signal of the integration unit may be obtained by the opening signal of the auxiliary switch. As shown in FIG. 2 , the rising edge transition signal of the S 2 driving signal at time t2 is the opening signal of the auxiliary switch. As shown in FIG. 9, the rising edge transition signal of the S R driving signal at time t 2 is the auxiliary signal. The enable signal of the switch can be obtained by detecting this rising edge transition signal. It should be noted that the enable signal may also be synchronized with this rising edge transition signal, or may be obtained by delaying the rising edge transition signal with a certain delay.
進一步地,在某些實施例中,對於臨界連續模式來說,積分電路的使能信號可以通過檢測激磁負電流的過零點(如第4圖,t1時刻;如第10圖,t1時刻)來獲得。具體而言,可以通過電流互感器,取樣電阻或者功率器件內阻如輔助開關的自身內阻來實現激磁負電流過零點的檢測。 Further, in some embodiments, for the critical continuous mode, the enable signal of the integrating circuit may be detected by detecting the zero crossing of the negative excitation current (as shown in FIG. 4 and time t1; as shown in FIG. 10 and time t1). obtain. Specifically, the detection of the zero crossing point of the negative excitation current can be achieved by a current transformer, a sampling resistor or an internal resistance of the power device such as the internal resistance of the auxiliary switch.
需要說明的是,在某些實施例中,積分單元的復位信號可以通過輔助開關的關斷信號(如第2圖的t3時刻S2驅動信號的下降沿跳變信號,如第4圖的t2時刻SR驅動信號的下降沿跳變信號,如第9圖的t3時刻SR驅動信號的下降沿跳變信號,如第10圖的t2時刻S2驅動信號的下降沿跳變信號)來獲得,例如可以和輔助開關的關斷信號同步,或者對該關斷信號進行一定延遲得到。 It should be noted that, in some embodiments, the reset signal of the integration unit can be turned off by the auxiliary switch (such as the falling edge transition signal of the S 2 driving signal at time t3 in FIG. 2 , such as t2 in FIG. 4). The falling edge transition signal of the driving signal at time S R , such as the falling edge transition signal of the driving signal of S R at time t3 in FIG. 9, such as the falling edge transition signal of the driving signal of S 2 at time t 2 in FIG. 10). For example, it can be synchronized with the shutdown signal of the auxiliary switch, or obtained by delaying the shutdown signal.
第11圖係為一種控制裝置的一個具體實施例。如第11圖所示,控制裝置1100用於控制返馳式變換器1110,其中控制裝置1100包括:輸出電壓積分單元1120、比較控制單元1130和激磁負電流基準設定單元1140。返馳式變換器1110為RCD鉗位返馳式變換器,包含初級側開關單元、次級側整流單元、變壓器T和輸出電容Co,其中,初級側開關單元包含初級側功率開關管S1,次級側整流單元包含同步整流管SR,且次級側整流單元分別與變壓器T和輸出電容Co電氣連接。於本實施例中,返馳式變換器1110工作于斷續模式。 FIG. 11 is a specific embodiment of a control device. As shown in FIG. 11, the control device 1100 is used to control the flyback converter 1110. The control device 1100 includes an output voltage integration unit 1120, a comparison control unit 1130, and an excitation negative current reference setting unit 1140. The flyback converter 1110 is an RCD clamped flyback converter, including a primary-side switching unit, a secondary-side rectifying unit, a transformer T, and an output capacitor C o , wherein the primary-side switching unit includes a primary-side power switch S 1 The secondary-side rectifier unit includes a synchronous rectifier S R , and the secondary-side rectifier unit is electrically connected to the transformer T and the output capacitor C o respectively. In this embodiment, the flyback converter 1110 operates in a discontinuous mode.
在此實施例中,控制裝置1100通過同步整流管SR的第二次導通開通信號,如第9圖所示的t2時刻的SR驅動信號,以獲得使能信號,通過使能信號使能輸出電壓積分單元1120;輸出電壓積分單元1120根據接收的輸出電壓信號Vo進行積分,根據公式(2)以得到初級側線圈激磁負電流的幅值Im_n,並將其輸送到比較控制單元1130;比較控制單元1130通過比較激磁負電流幅值Im_n與激磁負電流基準設定單元1140的基準值Im_N,待Im_n達到基準值Im_N時,即Im_n大於或等於基準值Im_N時,比較控制單元1130輸出控制 信號以關斷同步整流管SR。同時,比較控制單元1130根據同步整流管SR的關斷信號輸出復位信號以復位輸出電壓積分單元1120。 In this embodiment, the control device 1100 uses the second turn-on signal of the synchronous rectifier tube S R , such as the S R driving signal at time t 2 shown in FIG. 9, to obtain an enable signal. It can output voltage integration unit 1120; the output voltage integration unit 1120 integrates according to the received output voltage signal V o , and obtains the amplitude I m_n of the primary-side coil exciting negative current according to formula (2), and sends it to the comparison control unit. 1130; the comparison control unit 1130 compares the excitation negative current amplitude I m_n with the reference value I m_N of the excitation negative current reference setting unit 1140, and when I m_n reaches the reference value I m_N , that is, when I m_n is greater than or equal to the reference value I m_N The comparison control unit 1130 outputs a control signal to turn off the synchronous rectifier S R. At the same time, the comparison control unit 1130 outputs a reset signal according to the shutdown signal of the synchronous rectifier S R to reset the output voltage integration unit 1120.
第12圖係為一種控制裝置的另一個具體實施例。如第12圖所示,該控制裝置1200用於控制返馳式變換器1210,該控制裝置1200包括:輸出電壓積分單元1220、比較控制單元1230和激磁負電流基準設定單元1240。返馳式變換器1210為有源鉗位返馳式變換器,包含初級側開關單元、次級側整流單元、變壓器T和輸出電容Co,其中,初級側開關單元包含初級側功率開關管S1和鉗位管S2,次級側整流單元包含同步整流管SR,且次級側整流單元分別與變壓器T和輸出電容Co電氣連接。於本實施例中,返馳式變換器工作于斷續模式。 Fig. 12 is another specific embodiment of a control device. As shown in FIG. 12, the control device 1200 is used to control the flyback converter 1210. The control device 1200 includes: an output voltage integration unit 1220, a comparison control unit 1230, and an excitation negative current reference setting unit 1240. The flyback converter 1210 is an active clamp flyback converter, including a primary-side switching unit, a secondary-side rectifying unit, a transformer T, and an output capacitor C o , wherein the primary-side switching unit includes a primary-side power switch S 1 and clamp tube S 2 , the secondary-side rectifier unit includes a synchronous rectifier tube S R , and the secondary-side rectifier unit is electrically connected to the transformer T and the output capacitor C o respectively. In this embodiment, the flyback converter operates in a discontinuous mode.
在此實施例中,控制裝置1200由鉗位管S2的開通信號,如第2圖的t2時刻的S2的開通信號,來獲得積分單元使能信號,使能信號用於使能輸出電壓積分單元1220;輸出電壓信號Vo輸送到輸出電壓積分單元1220;輸出電壓積分單元1220根據輸出電壓信號Vo進行積分,以得到初級側線圈激磁負電流的幅值Im_n,並將其輸送到比較控制單元1230;比較控制單元1230通過比較激磁負電流幅值Im_n與激磁負電流基準設定單元1240的基準值Im_N,待Im_n達到基準值Im_N時,比較控制單元1230輸出控制信號以關斷鉗位管S2。同時比較控制單元1230根據鉗位管S2的關斷信號輸出積分單元復位信號以復位輸出電壓積分單元1220。 In this embodiment, the control device 1200 obtains the integration unit enable signal from the turn-on signal of the clamp tube S 2 , such as the turn-on signal of S 2 at time t2 in FIG. 2 , and the enable signal is used to enable the output voltage. Integrating unit 1220; the output voltage signal V o is transmitted to the output voltage integrating unit 1220; the output voltage integrating unit 1220 integrates according to the output voltage signal V o to obtain the amplitude I m_n of the negative exciting current of the primary coil, and sends it to The comparison control unit 1230; the comparison control unit 1230 compares the excitation negative current amplitude I m_n with the reference value I m_N of the excitation negative current reference setting unit 1240, and when I m_n reaches the reference value I m_N , the comparison control unit 1230 outputs a control signal to Turn off the clamp tube S 2 . At the same time, the comparison control unit 1230 outputs an integration unit reset signal according to the turn-off signal of the clamp tube S 2 to reset the output voltage integration unit 1220.
針對激磁負電流基準值的設定,經研究可知:在低壓輸入(Vbus<nVo)時,無需激磁負電流的幫助,即可實現初級側功率管的零電壓開通(ZVS);在高壓輸入(Vbus>nVo)時,為了實
現初級側功率管的零電壓開通(ZVS),激磁負電流的最小幅值需滿足:
根據上述公式(7),對於一個特定電路設計來說,變壓器的匝數比n、激磁電感感量Lm以及寄生電容容值CEQ是固定的,為了實現初級側功率管的零電壓開通(ZVS),激磁負電流的基準值Im_N與輸入電壓Vbus和輸出電壓VO有關。由此,激磁負電流基準設定單元可基於返馳式變換器的輸入電壓Vbus和輸出電壓VO實時調整激磁負電流基準值Im_N。 According to the above formula (7), for a specific circuit design, the transformer's turns ratio n, the magnetizing inductance L m and the parasitic capacitance C EQ are fixed. In order to achieve the zero-voltage turn-on of the primary-side power tube ( ZVS), the reference value of the negative excitation current I m_N is related to the input voltage V bus and the output voltage V O. Therefore, the excitation negative current reference setting unit can adjust the excitation negative current reference value I m_N in real time based on the input voltage V bus and the output voltage V O of the flyback converter.
然而,採用上述方法,為了實時調整激磁負電流基準值Im_N,需要實時監控兩個變量:輸入電壓Vbus和輸出電壓VO,如此做法會增加控制的複雜性。進一步研究可知:返馳式變換器於高壓輸入(Vbus>nVo)的情況下工作時,可忽略輸出電壓對於激磁負電流基準值的影響,即激磁負電流的基準值僅僅與輸入電壓有關,從而大大簡化了激磁負電流基準值的設定。 However, using the above method, in order to adjust the excitation negative current reference value I m_N in real time, two variables need to be monitored in real time: the input voltage V bus and the output voltage V O. This will increase the complexity of control. Further research shows that when the flyback converter is operated under high voltage input (V bus > nV o ), the influence of the output voltage on the reference value of the negative excitation current can be ignored, that is, the reference value of the negative excitation current is only related to the input voltage. , Which greatly simplifies the setting of the reference value of the negative excitation current.
於某些實施例中,對於激磁負電流基準值的設定,可以有如下兩種設定方法:
固定基準值設定法:為實現全輸入電壓範圍內初級側功率開關管的零電壓開通(ZVS),激磁負電流的基準值按最大輸入電壓進行設定,即:
其中:Vbus_max為輸入電壓最大值。 Where: V bus_max is the maximum input voltage.
對固定基準值設定法來說,當輸入電壓為最大值Vbus_max時,恰好可以滿足初級側功率開關管的零電壓開通(ZVS);但當輸入電壓為低電壓時,該控制方法所產生的激磁負電流幅值比初級側功率管零電壓開通(ZVS)所需的激磁負電流的幅值大,由此會帶來額外的損耗,不利於效率優化。當然,在對效率要求不是很高的應用場合可以採用固定基準值設定法。 For the fixed reference value setting method, when the input voltage is the maximum value V bus_max , it can just meet the zero-voltage turn-on (ZVS) of the primary-side power switch; but when the input voltage is low, the control method produces The amplitude of the negative excitation current is larger than the amplitude of the negative excitation current required for the zero-voltage turn-on (ZVS) of the primary-side power tube, which will cause additional losses and is not conducive to efficiency optimization. Of course, in applications where efficiency requirements are not very high, a fixed reference value setting method can be used.
對效率要求比較高的應用場合,可以採激磁負電流基準值隨輸入電壓變化的設定方法來對變換器的效率進行優化。因此,可以將激磁負電流基準值設定為:
其中:Im_N(Vbus)為激磁負電流基準值。 Among them: Im_N (V bus ) is the reference value of the negative excitation current.
對於一個特定的電路設計,激磁電感感量Lm和寄生電容容值CEQ是固定的,由上述公式(10)可知,激磁負電流基準值與輸入電壓Vbus成正比,激磁負電流基準設定單元可根據輸入電壓檢測單元檢測出的輸入電壓值Vbus,直接計算出激磁負電流基準值Im_N。 For a specific circuit design, the magnetizing inductance L m and the parasitic capacitance C EQ are fixed. From the above formula (10), it can be known that the reference value of the negative excitation current is proportional to the input voltage V bus , and the reference value of the negative excitation current is set. The unit can directly calculate the reference value of the excitation negative current I m_N according to the input voltage value V bus detected by the input voltage detection unit.
第13圖係為一種控制裝置的再一個具體實施例。第13圖與第11圖的結構類似,但第13圖更包含激磁負電流基準設定單元的一具體實例。於第13圖所示,控制裝置1300更包含輸入電壓檢測單元1360,於本實施例中,輸入電壓檢測單元1360包含第一電阻R1和第二電阻R2,並通過第一電阻R1和第二電阻R2分壓的方式來檢測輸入電壓信息Vbus。激磁負電流基準設定單元1340接收來自輸入電壓檢測單元1360的輸入電壓信息Vbus,用於設定激磁負電流基準值Im_N,該激磁負電流基準值輸送到比較控制單元1330;輸出電壓積分單元1320根據輸入的輸出電壓信號進行積分,以得到初級側線圈激磁負電流的幅值Im_n,並將其輸送到比較控制單元1330。比較控制單元1330通過比較從輸出電壓積分單元1320得到的激磁負電流幅值Im_n與激磁負電流基準設定單元1340的激磁負電流基準值Im_N,待Im_n達到激磁負電流基準值Im_N時,比較控制單元1330輸出控制信號以關斷同步整流管SR,同時輸出積分單元復位信號以復位輸出電壓積分單元1320。與此同時,通過同步整流管的二次導通開通信號(第9圖,t2時刻的SR驅動信號)獲得積分單元使能信號,通過使能信號使能輸出電壓積分單元1320。 FIG. 13 is another specific embodiment of a control device. FIG. 13 is similar to the structure in FIG. 11, but FIG. 13 further includes a specific example of the excitation negative current reference setting unit. As shown in FIG. 13, the control device 1300 further includes an input voltage detection unit 1360. In this embodiment, the input voltage detection unit 1360 includes a first resistor R 1 and a second resistor R 2 , and the first resistor R 1 and The second resistor R 2 divides the voltage to detect the input voltage information V bus . The excitation negative current reference setting unit 1340 receives the input voltage information V bus from the input voltage detection unit 1360 and is used to set the excitation negative current reference value I m_N . The excitation negative current reference value is sent to the comparison control unit 1330; the output voltage integration unit 1320 Integrate according to the input output voltage signal to obtain the amplitude I m_n of the primary-side coil exciting negative current, and send it to the comparison control unit 1330. The comparison control unit 1330 compares the excitation negative current amplitude I m_n obtained from the output voltage integration unit 1320 with the excitation negative current reference value I m_N of the excitation negative current reference setting unit 1340, and waits for I m_n to reach the excitation negative current reference value I m_N The comparison control unit 1330 outputs a control signal to turn off the synchronous rectifier S R , and at the same time, outputs an integration unit reset signal to reset the output voltage integration unit 1320. At the same time, the integration unit enable signal is obtained by the secondary conduction turn-on signal of the synchronous rectifier tube (FIG. 9, SR drive signal at time t2), and the output voltage integration unit 1320 is enabled by the enable signal.
第14圖示出了一種控制裝置的再一個具體實施例。第14圖與第11圖的結構類似,但第14圖更包含激磁負電流基準設定單元的一具體實例。於第14圖所示,控制裝置1400更包含輸入電壓檢測單元1460,於本實施例中,輸入電壓檢測單元1460包含第一電阻R1和第二電阻R2,並通過電阻分壓方式來檢測輸入電壓信息Vbus。輸入電壓檢測單元1460將輸入電壓信息Vbus輸入到激磁負電流基準設定單元1440用於設定基準值;由鉗位管S2的開通信號來獲得積 分單元使能信號,通過使能信號使能輸出電壓積分單元1420;輸出電壓信號Vo輸送到輸出電壓積分單元1420;輸出電壓積分單元1420根據輸入的輸出電壓信號進行積分,以得到初級側線圈激磁負電流的幅值Im_n,並將其輸送到比較控制單元1430;比較控制單元1430通過比較從輸出電壓積分單元1420得到的激磁負電流幅值Im_n與激磁負電流基準設定單元1440的基準值Im_N,待Im_n達到基準值Im_N時,比較控制單元1430輸出控制信號以關斷鉗位管S2,同時輸出積分單元復位信號以復位輸出電壓積分單元1420。 Fig. 14 shows a further specific embodiment of a control device. FIG. 14 is similar to the structure in FIG. 11, but FIG. 14 further includes a specific example of the excitation negative current reference setting unit. As shown in FIG. 14, the control device 1400 further includes an input voltage detection unit 1460. In this embodiment, the input voltage detection unit 1460 includes a first resistor R 1 and a second resistor R 2 , and is detected by a resistance voltage division method. Input voltage information V bus . The input voltage detection unit 1460 inputs the input voltage information V bus to the excitation negative current reference setting unit 1440 for setting the reference value; the turning-on signal of the clamp tube S 2 is used to obtain the integration unit enable signal, and the output is enabled by the enable signal The voltage integration unit 1420; the output voltage signal Vo is sent to the output voltage integration unit 1420; the output voltage integration unit 1420 integrates according to the input output voltage signal to obtain the amplitude I m_n of the primary-side coil exciting negative current, and sends it to The comparison control unit 1430; the comparison control unit 1430 compares the excitation negative current amplitude I m_n obtained from the output voltage integration unit 1420 with the reference value I m_N of the excitation negative current reference setting unit 1440, and when I m_n reaches the reference value I m_N , The comparison control unit 1430 outputs a control signal to turn off the clamp tube S 2 , and simultaneously outputs an integration unit reset signal to reset the output voltage integration unit 1420.
此外,在本案較佳實施例中,還提供了一種控制方法,該控制方法可以應用於如第6圖-第14圖所示的返馳式變換器,返馳式變換器包含一輔助開關,參照第15圖所示,控制方法可以包括以下步驟:步驟S1510:通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值;步驟S1520:將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較;以及步驟S1530:根據比較結果控制輔助開關的關斷以實現返馳式變換器的初級側功率開關管的零電壓開通。 In addition, in the preferred embodiment of the present case, a control method is also provided. The control method can be applied to the flyback converter shown in FIG. 6 to FIG. 14. The flyback converter includes an auxiliary switch. Referring to FIG. 15, the control method may include the following steps: Step S1510: Obtain the amplitude of the exciting negative current in the flyback converter by integrating the output voltage of the flyback converter; Step S1520: The obtained amplitude value of the negative excitation current is compared with a reference value of the negative excitation current; and step S1530: controlling the turning-off of the auxiliary switch according to the comparison result to realize the zero-voltage turning on of the primary-side power switch of the flyback converter.
根據此實施例的控制方法,一方面,通過對返馳式變換器的輸出電壓進行積分來獲得返馳式變換器中的激磁負電流的幅值,可以實時地獲得不同輸出電壓下的激磁負電流的幅值;另一方面,將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,根據比較結果控制輔助開關的關斷,可以通過合理地設定激磁負電流 基準值,實現在全輸入電壓範圍內(例如90~264Vac)初級側開關管在不同輸出電壓下的零電壓開通。 According to the control method of this embodiment, on the one hand, by integrating the output voltage of the flyback converter to obtain the magnitude of the exciting negative current in the flyback converter, the exciting negative at different output voltages can be obtained in real time. The amplitude of the current; on the other hand, the obtained amplitude of the negative excitation current is compared with the reference value of the negative excitation current, and the auxiliary switch is turned off according to the comparison result. The negative excitation current can be set reasonably The reference value achieves zero-voltage turn-on of the primary-side switch tube at different output voltages in the full input voltage range (for example, 90 ~ 264Vac).
進一步地,在某些實施例中,控制方法還可以包括:將所獲得的激磁負電流的幅值與激磁負電流基準值進行比較,於激磁負電流的幅值大於激磁負電流基準值時控制輔助開關的關斷。 Further, in some embodiments, the control method may further include: comparing the obtained amplitude of the negative excitation current with a reference value of the negative excitation current, and controlling when the amplitude of the negative excitation current is greater than the reference value of the negative excitation current. Turn off the auxiliary switch.
進一步地,在某些實施例中,控制方法還可以包括:基於返馳式變換器的輸入電壓設定激磁負電流基準值。 Further, in some embodiments, the control method may further include: setting a reference value of the exciting negative current based on the input voltage of the flyback converter.
進一步地,在某些實施例中,基於返馳式變換器的輸入電壓設定激磁負電流基準值可以包括:基於返馳式變換器的輸入電壓的最大值設定激磁負電流基準值。 Further, in some embodiments, setting the reference value of the exciting negative current based on the input voltage of the flyback converter may include: setting the reference value of the exciting negative current based on the maximum value of the input voltage of the flyback converter.
此外,在某些實施例中,控制方法還可以包括:基於所述返馳式變換器的輸入電壓和輸出電壓設定激磁負電流基準值。 In addition, in some embodiments, the control method may further include: setting a reference value of the exciting negative current based on an input voltage and an output voltage of the flyback converter.
需要說明的是,在某些實施例中,返馳式變換器為RCD鉗位返馳式變換器或有源鉗位返馳式變換器。 It should be noted that, in some embodiments, the flyback converter is an RCD clamped flyback converter or an active clamped flyback converter.
需要說明的是,在某些實施例中,返馳式變換器的工作模式為斷續模式或臨界連續模式。 It should be noted that, in some embodiments, the operating mode of the flyback converter is a discontinuous mode or a critical continuous mode.
需要說明的是,在某些實施例中,輔助開關為同步整流管、鉗位管、或並聯在返馳式變換器的次級側整流單元上的開關。 It should be noted that, in some embodiments, the auxiliary switch is a synchronous rectifier tube, a clamp tube, or a switch connected in parallel to the secondary-side rectifier unit of the flyback converter.
進一步地,在某些實施例中,對返馳式變換器的輸出電壓進行積分包括:響應於使能信號通過積分電路開始對返馳式變換器的輸出電壓進行積分,以及響應於一復位信號對積分電路進行復位。 Further, in some embodiments, integrating the output voltage of the flyback converter includes: starting to integrate the output voltage of the flyback converter through an integration circuit in response to an enable signal, and in response to a reset signal Reset the integration circuit.
進一步地,在某些實施例中,在斷續模式下,通過輔助開關的開通信號得到所述使能信號;以及在臨界連續模式下,通過檢測激磁負電流的過零點得到使能信號。 Further, in some embodiments, in the discontinuous mode, the enable signal is obtained by an on signal of an auxiliary switch; and in the critical continuous mode, an enable signal is obtained by detecting a zero-crossing point of a negative excitation current.
進一步地,在某些實施例中,通過電流互感器、取樣電阻或者輔助開關的自身內阻來檢測激磁負電流的過零點。 Further, in some embodiments, the zero crossing of the negative excitation current is detected by a current transformer, a sampling resistor, or the internal resistance of the auxiliary switch.
進一步地,在某些實施例中,通過輔助開關的關斷信號得到復位信號。 Further, in some embodiments, the reset signal is obtained by an off signal of the auxiliary switch.
進一步地,在某些實施例中,實現返馳式變換器的初級側功率開關管的零電壓開通包括:通過返馳式變換器中的激磁電感與寄生電容的諧振來實現返馳式變換器的初級側功率開關管的零電壓開通。 Further, in some embodiments, implementing the zero-voltage turn-on of the primary-side power switch tube of the flyback converter includes: realizing the flyback converter by resonance of an excitation inductance and a parasitic capacitance in the flyback converter. The zero-voltage of the primary-side power switch is turned on.
本領域技術人員在考慮說明書及實踐本案之發明後,將容易想到本案的其它實施例。本申請旨在涵蓋本案的任何變型、用途或者適應性變化,這些變型、用途或者適應性變化遵循本案的一般性原理並包括本案未公開的本技術領域中之習知技術。且本案之說明書和實施例僅被視為示例性的,而本發明之範圍由所附申請專利範圍決定。 After considering the specification and practicing the invention of the present invention, those skilled in the art will easily think of other embodiments of the present invention. This application is intended to cover any alterations, uses, or adaptations to the present application. These alterations, uses, or adaptations follow the general principles of the present application and include techniques known in the art that are not disclosed in this application. And the description and examples in this case are only considered as exemplary, and the scope of the present invention is determined by the scope of the attached patent application.
應當理解的是,本案並不局限於上面已經描述並在附圖中示出的精確結構,並且可以在不脫離其範圍進行各種修改和改變。本案的範圍僅由所附的申請專利範圍來限制。 It should be understood that the present application is not limited to the precise structure that has been described above and shown in the drawings, and various modifications and changes can be made without departing from the scope thereof. The scope of this case is limited only by the scope of the attached patent application.
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TW200717978A (en) * | 2005-10-20 | 2007-05-01 | Delta Electronics Inc | Adaptive synchronous rectification control circuit and method thereof |
US20100027298A1 (en) * | 2008-07-31 | 2010-02-04 | Texas Instruments Incorporated | System and method for synchronous rectifier drive that enables converters to operate in transition and discontinuous mode |
TW201119170A (en) * | 2009-11-30 | 2011-06-01 | Grenergy Opto Inc | Secondary side protection method and device for switching power supply |
US20140204625A1 (en) * | 2013-01-22 | 2014-07-24 | Power Integrations, Inc. | Secondary controller for use in synchronous flyback converter |
Family Cites Families (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5757626A (en) * | 1996-06-21 | 1998-05-26 | Delta Electronics Inc. | Single-stage, single-switch, islolated power-supply technique with input-current shaping and fast output-voltage regulation |
CN102570891B (en) * | 2012-01-16 | 2014-08-13 | 浙江昱能光伏科技集成有限公司 | Flyback photovoltaic grid-connected inverter adopting interleaving parallel-connection active clamping technology |
CN104362856B (en) * | 2014-11-05 | 2016-08-24 | 无锡中汇汽车电子科技有限公司 | A kind of control method of Zero-voltage switch flyback changer |
CN104539163B (en) * | 2014-12-19 | 2018-01-19 | 广州金升阳科技有限公司 | The synchronous rectification control method and its control module of anti exciting converter |
US10116222B2 (en) * | 2015-02-06 | 2018-10-30 | Texas Instruments Incorporated | Soft switching flyback converter with primary control |
-
2017
- 2017-06-30 CN CN202110747540.6A patent/CN113595399A/en active Pending
- 2017-06-30 CN CN201710524223.1A patent/CN108696131A/en active Pending
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Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
TW200717978A (en) * | 2005-10-20 | 2007-05-01 | Delta Electronics Inc | Adaptive synchronous rectification control circuit and method thereof |
US20100027298A1 (en) * | 2008-07-31 | 2010-02-04 | Texas Instruments Incorporated | System and method for synchronous rectifier drive that enables converters to operate in transition and discontinuous mode |
TW201119170A (en) * | 2009-11-30 | 2011-06-01 | Grenergy Opto Inc | Secondary side protection method and device for switching power supply |
US20140204625A1 (en) * | 2013-01-22 | 2014-07-24 | Power Integrations, Inc. | Secondary controller for use in synchronous flyback converter |
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