公开(公告)号：US20060109695A1

公开(公告)日：2006-05-25

申请号：US10992227

申请日：2004-11-19

申请人： Yuancheng Ren ,  Fred Lee ,  Ming Xu

发明人： Yuancheng Ren ,  Fred Lee ,  Ming Xu

IPC分类号： H02M7/757

CPC分类号： H02M3/33592 ,  H02M3/33569 ,  Y02B70/1433 ,  Y02B70/1475

摘要： Power converters having reduced body diode conduction loss, reduced reverse recovery loss and lower switching noise, among other benefits, have a resonant capacitor Cr connected across an unfiltered output. The resonant capacitor Cr resonates with the leakage inductance Lk of the transformer. The resonant capacitor and leakage inductance are selected such that ½ a LC resonance period is equal to an ON time of each secondary switch S1 S2. The resonance provides zero current switching for secondary switches S1 S2, eliminates zero body diode conduction during dead times, and eliminates reverse recovery losses in the secondary switches. The present invention is applicable to many different circuit topologies such as full bridge, active clamp forward, push-pull forward, and center-tap secondary. The present converters provide high energy conversion efficiency and high frequency operation.

摘要翻译： 具有降低的体二极管导通损耗，降低的反向恢复损耗和较低开关噪声以及其他优点的功率转换器具有连接在未滤波输出端的谐振电容器Cr。 谐振电容器Cr与变压器的漏电感Lk共振。 谐振电容器和漏电感被选择为使得LC共振周期的1/2相当于每个次级开关S 1 S 2的导通时间。 谐振为次级开关S 1 S 2提供零电流开关，在死区时间消除零体二极管导通，并消除次级开关中的反向恢复损耗。 本发明可应用于许多不同的电路拓扑，例如全桥，有源钳前进，推挽前进和中心抽头次级。 本转换器提供高能量转换效率和高频操作。

公开(公告)号：US08331110B2

公开(公告)日：2012-12-11

申请号：US12638261

申请日：2009-12-15

申请人： Ming Xu ,  Ke Jin ,  Fred C. Lee

发明人： Ming Xu ,  Ke Jin ,  Fred C. Lee

IPC分类号： H02M3/335 ,  G05F3/04

CPC分类号： H02M3/158 ,  H02M3/073 ,  H02M3/1584

摘要： A power converter topology operates as a switching capacitor (capacitive voltage divider) converter during a first, preferably short portion of a switching cycle to provide excellent dynamic transient response and as a pulse width modulated converter during a second portion of a switching cycle to provide flexibility of voltage regulation and generality of application. This topology can be made self-driven and is capable of zero voltage switching. Therefore the power converter can be used as one of a plurality of branches of a multi-phase converter to enhance transient response. The respective branches can also be independently optimized for particular load levels and can be operated independently in a phase shedding manner to improve efficiency at low load. Further, the power converter or respective branches of a multi-phase power converter are compatible with non-linear control to further improve dynamic response.

摘要翻译： 电源转换器拓扑在切换周期的第一，最好是短的部分期间用作开关电容器（电容分压器）转换器，以在开关周期的第二部分期间提供优异的动态瞬态响应和作为脉宽调制的转换器，以提供灵活性 的电压调节和一般性的应用。 该拓扑结构可以是自驱动的，并且能够进行零电压切换。 因此，功率转换器可以用作多相转换器的多个分支之一，以增强瞬态响应。 相应的分支也可以针对特定的负载水平独立地进行优化，并且可以以相位切换方式独立地进行操作，以在低负载下提高效率。 此外，功率转换器或多相功率转换器的各个分支与非线性控制兼容以进一步改善动态响应。

公开(公告)号：US20120014148A1

公开(公告)日：2012-01-19

申请号：US13184788

申请日：2011-07-18

申请人： Qian Li ,  Fred C. Lee ,  Ming Xu ,  Chuanyun Wang

发明人： Qian Li ,  Fred C. Lee ,  Ming Xu ,  Chuanyun Wang

IPC分类号： H02M1/00

CPC分类号： H02M1/4216 ,  H02M1/4225 ,  H02M1/44 ,  H02M2001/0032 ,  H02M2003/1586 ,  Y02B70/126 ,  Y02B70/16 ,  Y02P80/112

摘要： Light load efficiency of a power factor correction circuit is improved by adaptive on-time control and providing for selection between a continuous conduction mode and a discontinuous conduction mode wherein the discontinuous conduction mode increases time between switching pulses controlling connection of a cyclically varying voltage to a filter/inductor that delivers a desired DC voltage and thus can greatly reduce the switching frequency at light loads where switching frequency related losses dominate efficiency. The mode for controlling switching is preferably selected for each switching pulse within a half cycle of the cyclically varying input voltage. A multi-phase embodiment allows cancellation of EMI noise at harmonics of the switching frequency and adaptive change of phase angle allows for cancellation of dominant higher order harmonics as switching frequency is reduced.

摘要翻译： 通过自适应导通时间控制来提高功率因数校正电路的轻负载效率，并提供连续导通模式和不连续导通模式之间的选择，其中不连续导通模式增加了控制周期性变化的电压连接到开关脉冲之间的时间 滤波器/电感器提供所需的直流电压，因此可以大大降低开关频率相关损耗占优势的轻负载时的开关频率。 优选地，在循环变化的输入电压的半周期内针对每个开关脉冲选择用于控制切换的模式。 多相实施例允许在开关频率的谐波处消除EMI噪声，并且由于开关频率降低，相位角的自适应变化允许抵消主要高阶谐波。

公开(公告)号：US07872886B2

公开(公告)日：2011-01-18

申请号：US12034229

申请日：2008-02-20

申请人： Ming Xu ,  Julu Sun ,  Ya Liu ,  Fred C. Lee

发明人： Ming Xu ,  Julu Sun ,  Ya Liu ,  Fred C. Lee

IPC分类号： H02M7/00

CPC分类号： H02M3/1584 ,  H02M2001/0074 ,  Y02B70/1425 ,  Y10T307/685

摘要： Improved regulation and transient response are provided by a power supply architecture providing both unregulated and regulated voltage converters in parallel but deriving input power from separate power supplies connected in series wherein regulated and unregulated branches each provide a substantially fixed and constant proportion of the output current. The series connection of input power sources may provide a further feedback mechanism in addition to feedback for regulation which enhances overall performance. As a perfecting feature of the invention, inductor-less resonant converters which are switched in an interleaved fashion may be used in the unregulated branch while substantially cancelling the characteristic large output voltage ripple thereof.

摘要翻译： 改进的调节和瞬态响应由电源架构提供，其提供并联的不稳压和稳压电压转换器，但是从串联连接的单独电源导出输入功率，其中调节和未调节的分支各自提供基本上固定的和恒定的输出电流比例。 输入电源的串联连接可以提供进一步的反馈机制，以及增强整体性能的调节反馈。 作为本发明的完善特征，可以在非调节支路中使用以交错方式切换的无电感谐振转换器，同时基本上消除其特征性的大输出电压纹波。

公开(公告)号：US07821375B2

公开(公告)日：2010-10-26

申请号：US11668229

申请日：2007-01-29

申请人： Yan Dong ,  Ming Xu ,  Fred C. Lee

发明人： Yan Dong ,  Ming Xu ,  Fred C. Lee

IPC分类号： H01F27/28 ,  H01F5/00

CPC分类号： H02M3/1584 ,  H01F17/0006 ,  H01F27/255 ,  H01F37/00

摘要： A multiple phase buck converter or boost converter, or buck-boost converter has an inductor in each phase. The inductors are inversely coupled. In a first embodiment, the converter includes a toroidal magnetic core with inductors extending under and over opposite sides of the toroidal magnetic core. The coupled inductors are thereby inversely coupled and have a relatively low ohmic resistance. In a second embodiment, the converter comprises a ladder-shaped magnetic core (i.e. having parallel sides, and connecting rungs). In this case, the inductors extend under the sides, and over the rungs. Each inductor is disposed over a separate rung. The ladder-shaped magnetic core is preferably disposed flat on a circuit board. Inverse coupling and low ohmic resistance are also provided in the second embodiment having the ladder structure.

公开(公告)号：US20080239771A1

公开(公告)日：2008-10-02

申请号：US11834281

申请日：2007-08-06

申请人： Chuanyun Wang ,  Ming Xu ,  Fred C. Lee

发明人： Chuanyun Wang ,  Ming Xu ,  Fred C. Lee

IPC分类号： H02M1/12

CPC分类号： H02M1/12 ,  H02M1/42 ,  H02M3/1584 ,  H02M2003/1586 ,  Y02B70/12

摘要： In a power converter having m=two or more channels of power factor correction (PFC) circuits connected in parallel and an electromagnetic interference (EMI) filter connected in series therewith, phase shifts in switching between the respective PFC channels can allow increase of EMI filter corner frequency allowing reduction of size and cost of the EMI filter at some switching frequencies. Asymmetrical phase shifts (other than 360°/m) such as 360°/2m and other phase shifts and variations in m allow increase of EMI filter corner frequency at switching frequencies where symmetrical, 360°/m phase shifts provide no benefit to EMI filter design by providing cancellation or partial cancellation of different harmonics of the switching noise; which cancellation may be arranged to be complementary to the EMI filter function at more than one peak of the noise spectrum. (Such asymmetrical phase shifts do not significantly increase ripple and consequent switching noise). Alteration of m and corresponding alteration of phase shift may be performed adaptively for purposes of improving efficiency at light loads and the like.

摘要翻译： 在具有并联连接的m = 2个或更多个功率因数校正（PFC）电路的通道和与其串联连接的电磁干扰（EMI））滤波器的功率转换器中，在相应PFC通道之间的切换中的相移可允许增加EMI滤波器 转角频率允许在某些开关频率下降低EMI滤波器的尺寸和成本。 360°/ 2m以外的不对称相移（360°/ 2m）和其它相移以及m的变化允许在对称的开关频率下增加EMI滤波器转角频率，360°/ m相移对EMI滤波器无益 通过提供消除或部分消除开关噪声的不同谐波的设计; 该消除可以被布置为在噪声谱的多于一个峰值处与EMI滤波器功能互补。 （这种非对称相移不会显着增加纹波和随之而来的开关噪声）。 m的改变和相移的相应改变可以自适应地进行，以提高轻负载等的效率。

公开(公告)号：US06989997B2

公开(公告)日：2006-01-24

申请号：US10603097

申请日：2003-06-25

申请人： Ming Xu ,  Fred C. Lee

发明人： Ming Xu ,  Fred C. Lee

IPC分类号： H02M3/335

CPC分类号： H02M3/158 ,  H02M3/33576 ,  Y02B70/1425 ,  Y02B70/1433

摘要： Buck converters having a resonant inductor Lr, resonant capacitor Cr, and synchronous switch Q3 that together provide reduced switching loss and soft switching. In operation, the resonant inductor Lr is charged during a time period A. Then, Lr is freewheeling and provides current to an output inductor Lo. Then, Q3 is turned OFF, and energy from the resonant inductor Lr charges the resonant capacitor Cr. Finally, energy from the resonant capacitor Cr is provided to the output inductor and load. The output power can be adjusted by phase control of the operation of switch Q3. In alternative embodiments, the circuit has a pair of coupled inductors L1 L2 or an isolation transformer 40. The coupled inductors have a polarity selected so that the output voltage is reduced, thereby allowing top switch Q1 to have a greater duty cycle. These circuits feature no body diode loss in the switch Q3.

摘要翻译： 具有谐振电感器Lr，谐振电容器Cr和同步开关Q 3的降压转换器一起提供降低的开关损耗和软开关。 在运行中，谐振电感器Lr在时间段A内被充电。然后，Lr是续流并且向输出电感器Lo提供电流。 然后，Q 3截止，来自谐振电感器Lr的能量对谐振电容器Cr充电。 最后，将谐振电容器Cr的能量提供给输出电感器和负载。 可以通过开关Q 3的操作的相位控制来调节输出功率。 在替代实施例中，电路具有一对耦合电感器L 1 L 2或隔离变压器40。 耦合电感器具有选择的极性，使得输出电压降低，从而允许顶部开关Q1具有更大的占空比。 这些电路在开关Q 3中没有体二极管损耗。

公开(公告)号：US20110140679A1

公开(公告)日：2011-06-16

申请号：US12638261

申请日：2009-12-15

申请人： Ming Xu ,  Ke Jin ,  Fred C. Lee

发明人： Ming Xu ,  Ke Jin ,  Fred C. Lee

IPC分类号： G05F1/10

CPC分类号： H02M3/158 ,  H02M3/073 ,  H02M3/1584

摘要： A power converter topology operates as a switching capacitor (capacitive voltage divider) converter during a first, preferably short portion of a switching cycle to provide excellent dynamic transient response and as a pulse width modulated converter during a second portion of a switching cycle to provide flexibility of voltage regulation and generality of application. This topology can be made self-driven and is capable of zero voltage switching. Therefore the power converter can be used as one of a plurality of branches of a multi-phase converter to enhance transient response. The respective branches can also be independently optimized for particular load levels and can be operated independently in a phase shedding manner to improve efficiency at low load. Further, the power converter or respective branches of a multi-phase power converter are compatible with non-linear control to further improve dynamic response.

摘要翻译： 电源转换器拓扑在开关周期的第一，最好是短的部分期间用作开关电容器（电容分压器）转换器，以在开关周期的第二部分期间提供优异的动态瞬态响应和作为脉冲宽度调制的转换器，以提供灵活性 的电压调节和一般性的应用。 该拓扑结构可以是自驱动的，并且能够进行零电压切换。 因此，功率转换器可以用作多相转换器的多个分支之一，以增强瞬态响应。 相应的分支也可以针对特定的负载水平独立地进行优化，并且可以以相位切换方式独立地进行操作，以在低负载下提高效率。 此外，功率转换器或多相功率转换器的各个分支与非线性控制兼容以进一步改善动态响应。

公开(公告)号：US07233132B1

公开(公告)日：2007-06-19

申请号：US11341874

申请日：2006-01-30

申请人： Yan Dong ,  Ming Xu ,  Fred C. Lee

发明人： Yan Dong ,  Ming Xu ,  Fred C. Lee

IPC分类号： G05F1/575 ,  G05F1/618

CPC分类号： H02M3/1584 ,  H02M2001/0009

摘要： Voltage regulators often have coupled output inductors because coupled output inductors provide improvements in cost and efficiency. Coupled inductors are often used in multi-phase voltage regulators. Feedback control of voltage regulators often requires accurate and responsive sensing of output current. Provided is a technique for accurately sensing the magnitude of output current in coupled inductors. An RC circuit (comprising a resistor and capacitor in series) is connected in parallel with the coupled inductor. The inductor has a leakage inductance Lk and a DC (ohmic) resistance of DCR. The resistor and capacitor are selected such that an RC time constant is equal to an L/R time constant of Lk/DCR. With the matching time constants, a sum of voltages on the capacitors is accurately proportional to a sum of currents flowing in the output inductors. Also provided is a technique for sensing current when an uncoupled center tap inductor is present.

摘要翻译： 电压调节器通常具有耦合输出电感器，因为耦合的输出电感器提供了成本和效率的改进。 耦合电感通常用于多相电压调节器。 电压调节器的反馈控制通常需要精确和响应的输出电流感测。 提供了一种用于精确地感测耦合电感器中的输出电流的大小的技术。 RC电路（包括串联的电阻器和电容器）与耦合的电感器并联连接。 电感器具有DCR的漏电感Lk和DC（欧姆）电阻。 选择电阻器和电容器使得RC时间常数等于Lk / DCR的L / R时间常数。 使用匹配的时间常数，电容器上的电压之和与输出电感器中流过的电流之和正好成正比。 还提供了当存在非耦合中心抽头电感器时感测电流的技术。

公开(公告)号：US08803489B2

公开(公告)日：2014-08-12

申请号：US13184788

申请日：2011-07-18

申请人： Qian Li ,  Fred C. Lee ,  Ming Xu ,  Chuanyun Wang

发明人： Qian Li ,  Fred C. Lee ,  Ming Xu ,  Chuanyun Wang

IPC分类号： G05F1/70

CPC分类号： H02M1/4216 ,  H02M1/4225 ,  H02M1/44 ,  H02M2001/0032 ,  H02M2003/1586 ,  Y02B70/126 ,  Y02B70/16 ,  Y02P80/112

摘要： Light load efficiency of a power factor correction circuit is improved by adaptive on-time control and providing for selection between a continuous conduction mode and a discontinuous conduction mode wherein the discontinuous conduction mode increases time between switching pulses controlling connection of a cyclically varying voltage to a filter/inductor that delivers a desired DC voltage and thus can greatly reduce the switching frequency at light loads where switching frequency related losses dominate efficiency. The mode for controlling switching is preferably selected for each switching pulse within a half cycle of the cyclically varying input voltage. A multi-phase embodiment allows cancellation of EMI noise at harmonics of the switching frequency and adaptive change of phase angle allows for cancellation of dominant higher order harmonics as switching frequency is reduced.

摘要翻译： 通过自适应导通时间控制来提高功率因数校正电路的轻负载效率，并提供连续导通模式和不连续导通模式之间的选择，其中不连续导通模式增加了控制周期性变化的电压连接到开关脉冲之间的时间 滤波器/电感器提供所需的直流电压，因此可以大大降低开关频率相关损耗占优势的轻负载时的开关频率。 优选地，在循环变化的输入电压的半周期内针对每个开关脉冲选择用于控制切换的模式。 多相实施例允许在开关频率的谐波处消除EMI噪声，并且由于开关频率降低，相位角的自适应变化允许抵消主要高阶谐波。