US 12,395,088 B2
Input responsive protection and frequency control of series connected converters
Dehai Lou, Shanghai (CN); Pian Zhou, Shanghai (CN); Xin Wang, Shanghai (CN); and Teng Liu, Shanghai (CN)
Assigned to Delta Electronics (Shanghai) Co., Ltd., Shanghai (CN)
Filed by Delta Electronics (Shanghai) Co., Ltd., Shanghai (CN)
Filed on Aug. 31, 2022, as Appl. No. 17/900,505.
Claims priority of application No. 202111031096.4 (CN), filed on Sep. 3, 2021.
Prior Publication US 2023/0073099 A1, Mar. 9, 2023
Int. Cl. H02M 3/335 (2006.01); H02M 1/00 (2006.01)
CPC H02M 3/33584 (2013.01) [H02M 1/0074 (2021.05); H02M 3/33573 (2021.05); H02M 1/0035 (2021.05)] 17 Claims
OG exemplary drawing
 
1. A power converter, comprising:
a plurality of power units, wherein each of the plurality of power units comprises an input capacitor, input terminals of the plurality of power units are connected to each other in series, and output terminals of the plurality of power units are connected to each other in parallel; and
a plurality of local controllers, electrically connected to the plurality of power units respectively, wherein each of the plurality of local controllers is configured to control an operation of switching devices in the corresponding power unit, each of the plurality of local controllers receives an input capacitor voltage on the input capacitor of the corresponding power unit, an input reference voltage and an output voltage of the power converter, wherein in each of the plurality of power units and the corresponding local controller, when an input difference between the input reference voltage and the input capacitor voltage is smaller than a first set value, the local controller controls a switching frequency of the switching devices in the corresponding power unit to jump to a preset frequency,
wherein each of the plurality of local controllers comprises a calculator and a decider, in each of the plurality of power units and the corresponding local controller, the calculator receives the input capacitor voltage and the input reference voltage, and calculates the input difference by comparing the input reference voltage wi Input capacitor voltage, and the decider receives the input difference and compares the input difference with the first set value and a second set value, where the first set value is smaller than the second set value,
wherein each of the plurality of local controllers further comprises a frequency hopping controller, in each of the plurality of power units and the corresponding local controller, when the decider determines that the input difference is smaller than the first set value, the frequency hopping controller generates the preset frequency according to the output voltage, and the local controller controls the switching devices in the corresponding power unit to operate at the preset frequency,
wherein each of the plurality of local controllers further comprises a disabling pulse controller, in each of the plurality of power units and the corresponding local controller, when the decider determines that the input difference is larger than the second set value, the disabling pulse controller outputs a disabling polse command, and the local controller controls the switching devices in the corresponding power unit to stop operating accordingly.