公开(公告)号：US20170244316A1

公开(公告)日：2017-08-24

申请号：US15585715

申请日：2017-05-03

Applicant: Apple Inc.

Inventor： Vijay Phadke

IPC: H02M1/34 ,  H02M3/335

CPC classification number: H02M3/33546 ,  H02M1/34 ,  H02M3/335 ,  H02M3/33523 ,  H02M3/33569 ,  H02M2001/0009 ,  H02M2001/0058 ,  H02M2001/342 ,  Y02B70/1433 ,  Y02B70/1491

Abstract: Systems and methods for operating improved flyback converters are disclosed, in which leakage energy is returned to the input power source rather than to the output load, while still achieving zero voltage switching (i.e., ZVS) operation. In some embodiments, the improved converters may transfer the energy stored in the leakage inductance to a snubber capacitor(s) at the instant of turning off of the control switch. Further, the improved converter embodiments may also retain the stored energy in the snubber capacitor(s) when the power is being delivered to the load by the secondary circuits. The improved converter embodiments may start the transfer of leakage energy stored in the snubber capacitor(s) to the primary winding once the energy stored in the transformer is delivered to the load. Finally, the improved converter embodiments may intelligently control their active clamp switches such that all leakage inductance energy is returned to the input source.

公开(公告)号：US11271468B2

公开(公告)日：2022-03-08

申请号：US16209633

申请日：2018-12-04

Applicant: Apple Inc.

Inventor： Vijay Phadke

IPC: H02M3/335 ,  H02M3/158 ,  H02M1/08

Abstract: Disclosed herein are synchronous rectifier control techniques for Discontinuous Current Mode (DCM) converters. These techniques may be particularly advantageous where the current shape is triangular in nature with a fixed down-slope. Such converters may include DCM flyback converters and DCM buck converters. The proposed control techniques can reduce body diode conduction of the synchronous rectifier and optimize turn-off timing, while negating the effect of parasitic circuit elements. These techniques may also help simplify the control of synchronous rectifiers operated in parallel mode. Finally, such techniques may also help achieve higher performance in variable output voltage converters and converters that operate at high switching frequencies.

公开(公告)号：US20190222127A1

公开(公告)日：2019-07-18

申请号：US16366611

申请日：2019-03-27

Applicant: Apple Inc.

Inventor： Vijay Phadke

IPC: H02M3/335 ,  H02M1/34

Abstract: Systems and methods for operating improved flyback converters are disclosed, in which leakage energy is returned to the input power source rather than to the output load, while still achieving zero voltage switching (i.e., ZVS) operation. In some embodiments, the improved converters may transfer the energy stored in the leakage inductance to a snubber capacitor(s) at the instant of turning off of the control switch. Further, the improved converter embodiments may also retain the stored energy in the snubber capacitor(s) when the power is being delivered to the load by the secondary circuits. The improved converter embodiments may start the transfer of leakage energy stored in the snubber capacitor(s) to the primary winding once the energy stored in the transformer is delivered to the load. Finally, the improved converter embodiments may intelligently control their active clamp switches such that all leakage inductance energy is returned to the input source.

公开(公告)号：US20190222113A1

公开(公告)日：2019-07-18

申请号：US16365100

申请日：2019-03-26

Applicant: Apple Inc.

Inventor： Marco A. Davila ,  Joao L. Andres ,  Bogdan T. Bucheru ,  Vijay Phadke

IPC: H02M1/34 ,  H02M3/335 ,  H02M1/08

Abstract: This disclosure describes a flyback converter with a series-parallel mode (SPM) active clamp. The active clamp, coupled in parallel with the primary coil, may include a clamp switch, two or more snubber capacitors, and associated diodes. The active clamp may be configured to absorb and retain the leakage energy from the leakage inductance of the flyback converter. The clamp switch may be turned on selectively as the primary switch approaches one of a plurality peak values to adjust frequencies of the switching devices. With the active clamp circuit, the flyback converter may first re-capture the leakage energy in the active clamp circuit and then recover it back to the power source.

公开(公告)号：US20180083546A1

公开(公告)日：2018-03-22

申请号：US15829253

申请日：2017-12-01

Applicant: Apple Inc.

Inventor： Vijay Phadke

IPC: H02M3/335 ,  H02M1/34 ,  H02M1/00

CPC classification number: H02M3/33546 ,  H02M1/34 ,  H02M3/335 ,  H02M3/33523 ,  H02M3/33569 ,  H02M2001/0009 ,  H02M2001/0058 ,  H02M2001/342 ,  Y02B70/1433 ,  Y02B70/1491

Abstract: Systems and methods for operating improved flyback converters are disclosed, in which leakage energy is returned to the input power source rather than to the output load, while still achieving zero voltage switching (i.e., ZVS) operation. In some embodiments, the improved converters may transfer the energy stored in the leakage inductance to a snubber capacitors) at the instant of turning off of the control switch. Further, the improved converter embodiments may also retain the stored energy in the snubber capacitor(s) when the power is being delivered to the load by the secondary circuits. The improved converter embodiments may start the transfer of leakage energy stored in the snubber capacitor(s) to the primary winding once the energy stored in the transformer is delivered to the load. Finally, the improved converter embodiments may intelligently control their active clamp switches such that all leakage inductance energy is returned to the input source.

公开(公告)号：US20160365801A1

公开(公告)日：2016-12-15

申请号：US15042885

申请日：2016-02-12

Applicant: Apple Inc.

Inventor： Vijay Phadke

IPC: H02M3/335

CPC classification number: H02M3/33546 ,  H02M1/34 ,  H02M3/335 ,  H02M3/33523 ,  H02M3/33569 ,  H02M2001/0009 ,  H02M2001/0058 ,  H02M2001/342 ,  Y02B70/1433 ,  Y02B70/1491

Abstract: Systems and methods for operating improved flyback converters are disclosed, in which leakage energy is returned to the input power source rather than to the output load, while still achieving zero voltage switching (i.e., ZVS) operation. In some embodiments, the improved converters may transfer the energy stored in the leakage inductance to a snubber capacitor(s) at the instant of turning off of the control switch. Further, the improved converter embodiments may also retain the stored energy in the snubber capacitor(s) when the power is being delivered to the load by the secondary circuits. The improved converter embodiments may start the transfer of leakage energy stored in the snubber capacitor(s) to the primary winding once the energy stored in the transformer is delivered to the load. Finally, the improved converter embodiments may intelligently control their active clamp switches such that all leakage inductance energy is returned to the input source.

Abstract translation: 公开了用于操作改进的反激转换器的系统和方法，其中泄漏能量返回到输入电源而不是输出负载，同时仍然实现零电压切换（即，ZVS）操作。 在一些实施例中，改进的转换器可以在断开控制开关的瞬间将存储在漏电感中的能量传送到缓冲电容器。 此外，当功率由次级电路传送到负载时，改进的转换器实施例还可以将存储的能量保持在缓冲电容器中。 一旦存储在变压器中的能量被传送到负载，改进的转换器实施例可以开始将存储在缓冲电容器中的漏电能量传送到初级绕组。 最后，改进的转换器实施例可以智能地控制它们的有源钳位开关，使得所有漏电感能量返回到输入源。