US 11,683,008 B2
Photovoltaic inverter, photovoltaic system, and method for controlling discharging
Xinyu Wang, Anhui (CN); Anying Jiang, Anhui (CN); Shun Ding, Anhui (CN); Yanfei Yu, Anhui (CN); and Xiaoxun Li, Anhui (CN)
Assigned to Sungrow Power Supply Co., Ltd., Hefei (CN)
Filed by Sungrow Power Supply Co., Ltd., Hefei (CN)
Filed on Jul. 20, 2021, as Appl. No. 17/380,418.
Claims priority of application No. 202010711947.9 (CN), filed on Jul. 22, 2020.
Prior Publication US 2022/0029582 A1, Jan. 27, 2022
Int. Cl. H02S 40/32 (2014.01); H02M 1/32 (2007.01); H02M 1/00 (2006.01)
CPC H02S 40/32 (2014.12) [H02M 1/007 (2021.05); H02M 1/322 (2021.05)] 15 Claims
OG exemplary drawing
 
1. A photovoltaic inverter, comprising:
a first direct current to direct current (DCDC) converter;
an inverter circuit;
a first discharging circuit; and
a controller, wherein
the first DCDC converter is connected to a photovoltaic array at an input side of the first DCDC converter, and is connected to an input side of the inverter circuit at an output side of the first DCDC converter;
a port capacitor is connected between a positive input end and a negative input end of the first DCDC converter, wherein the port capacitor comprises an X capacitor and a first group of Y capacitors;
the first discharging circuit is connected between a common terminal of the first group of Y capacitors and a direct current bus, wherein the common terminal of the first group of Y capacitors is grounded;
the controller is configured to control, when receiving a rapid shutdown instruction, the first discharging circuit to operate; and
the first discharging circuit is configured to discharge electrical energy of the port capacitor; wherein the first DCDC converter and the inverter circuit are in a common negative connection; a second group of Y capacitors are connected between a positive input end and a negative input end of the inverter circuit, wherein a common terminal of the second group of Y capacitors is grounded; and the first discharging circuit is further configured to discharge electrical energy of the second group of Y capacitors, wherein the first discharging circuit comprises an insulation resistance detection circuit.