公开(公告)号：US09544956B2

公开(公告)日：2017-01-10

申请号：US14628372

申请日：2015-02-23

Applicant: Virginia Tech Intellectual Properties, Inc.

Inventor： Xuebing Chen ,  Daocheng Huang ,  Qiang Li ,  Fred C. Lee

IPC: H05B33/08

CPC classification number: H05B33/0815 ,  H05B33/0851

Abstract: In a two-stage power converter providing voltage regulation in a first stage, zero voltage switching (ZVS) is provided in switches in an unregulated, constant frequency second stage of a two-stage power converter by an inductor of a CLL resonant circuit connected in parallel with both a series connection of an external inductor and a primary winding of one or more transformers connected in series and an output of the switching circuit so that the output capacitances of the switches can be charged and discharged, respectively, by current in the parallel-connected inductor and independently of current in the magnetizing inductance of the transformer. Therefore, the magnetizing inductance of the transformer can be made sufficiently large to balance currents delivered to respective loads as is particularly desirable for driving a plurality of unbalanced LED strings independently of the value of the parallel-connected inductor which is desirably small.

Abstract translation: 在第一级提供电压调节的两级电力转换器中，通过CLL谐振电路的电感器连接在两级功率转换器的未调节恒定频率第二级的开关中提供零电压开关（ZVS） 与串联连接的一个或多个变压器的外部电感器和初级绕组的串联连接和开关电路的输出两者并联，使得开关的输出电容可以分别由并联的电流充电和放电 并且独立于变压器励磁电感中的电流。 因此，可以使变压器的磁化电感足够大以平衡输送到各个负载的电流，这是特别适合于驱动多个不平衡LED串，独立于期望较小的并联电感器的值。

公开(公告)号：US20150289331A1

公开(公告)日：2015-10-08

申请号：US14628372

申请日：2015-02-23

Applicant: Virginia Tech Intellectual Properties, Inc.

Inventor： Xuebing Chen ,  Daocheng Huang ,  Qiang Li ,  Fred C. Lee

IPC: H05B33/08

CPC classification number: H05B33/0815 ,  H05B33/0851

Abstract: Zero voltage switching (ZVS) is provided in switches of a switching circuit in a second stage of a power converter by an inductor of a CLL resonant circuit connected in parallel with both a primary winding of one or more transformers connected in series and an output of the switching circuit so that the parasitic output capacitances of the switches can be charged and discharged, respectively, during the dead-time of the switching circuit by current in the inductor and independently of current in the magnetizing inductance of the transformer. Therefore, the magnetizing inductance of the transformer can be made sufficiently large to balance currents delivered to respective loads that may be unbalanced as is particularly desirable for driving a plurality of LED strings for illumination and is consistent with controlled dimming of the LED strings. A current sensor such as a resistance can be place in any LED string and all transformer modules and string currents cross regulated,

Abstract translation: 通过与串联连接的一个或多个变压器的初级绕组并联连接的CLL谐振电路的电感器在功率转换器的第二级的开关电路的开关中提供零电压开关（ZVS），并且输出 开关电路，使开关的寄生输出电容分别在开关电路的死区时由电感器中的电流而分别进行充放电，而与变压器的励磁电感无关。 因此，可以使变压器的励磁电感足够大以平衡输送到各个负载的电流，这些电流可能是不平衡的，因为对于驱动多个用于照明的LED串特别理想，并且与LED串的受控调光一致。 电流传感器如电阻可以放置在任何LED串中，所有变压器模块和串电流交叉调节，