US 12,136,819 B2
Power conversion system
Wei-Lin Liu, Taoyuan (TW)
Assigned to DARFON ELECTRONICS CORP., Taoyuan (TW)
Filed by DARFON ELECTRONICS CORP., Taoyuan (TW)
Filed on Apr. 5, 2023, as Appl. No. 18/131,357.
Claims priority of provisional application 63/328,267, filed on Apr. 6, 2022.
Claims priority of application No. 112111919 (TW), filed on Mar. 29, 2023.
Prior Publication US 2023/0327448 A1, Oct. 12, 2023
Int. Cl. H02J 3/32 (2006.01); H02J 3/38 (2006.01); H02J 7/00 (2006.01)
CPC H02J 3/32 (2013.01) [H02J 3/381 (2013.01); H02J 7/0063 (2013.01); H02J 2300/24 (2020.01)] 9 Claims
OG exemplary drawing
 
1. A power conversion system (PCS) comprising:
an alternating current (AC) power port coupled to a photovoltaic inverter;
a first direct current (DC) power port coupled to a rechargeable battery;
a second direct current (DC) power port coupled to a solar panel;
a high voltage capacitor;
a first DC converter coupled between the high voltage capacitor and the first DC power port;
a second DC converter coupled between the high voltage capacitor and the second DC power port;
a DC/AC inverter coupled between the high voltage capacitor and the AC power port; and
a microcontroller unit (MCU) for adjusting a frequency of an AC output from the AC power port by the power conversion system according to a voltage difference between two ends of the high voltage capacitor;
wherein when the microcontroller unit detects mains off-grid, and the voltage difference is greater than a first critical value, the microcontroller unit sets the frequency of the AC output from the AC power port as a cut-off frequency, so that the photovoltaic inverter stops outputting power;
wherein when the microcontroller unit detects mains off-grid, and the voltage difference is between the first critical value and a second critical value for a continuous time exceeding a predetermined time length, the microcontroller unit sets the frequency of the AC output from the AC power port as the cut-off frequency;
wherein when the microcontroller unit detects mains off-grid, and the voltage difference is between the second critical value and a third critical value, the microcontroller unit increases the frequency of the AC output from the AC power port by a first predetermined value; and
wherein the first critical value is greater than the second critical value, and the second critical value is greater than the third critical value.