US 9,812,986 B2
Apparatus for balancing voltages of DC link capacitor in inverter
Ii-Pyo Hong, Gyeonggi-do (KR)
Assigned to LSIS CO., LTD., Gyeonggi-Do (KR)
Filed by LSIS CO., LTD., Gyeonggi-do (KR)
Filed on Jan. 6, 2017, as Appl. No. 15/400,595.
Claims priority of application No. 10-2016-0037389 (KR), filed on Mar. 29, 2016.
Prior Publication US 2017/0288573 A1, Oct. 5, 2017
Int. Cl. H02M 7/487 (2007.01)
CPC H02M 7/487 (2013.01) 5 Claims
OG exemplary drawing
 
1. An apparatus for balancing voltages applied to first and second capacitors in an inverter system including a smoothing unit configured with the first and second capacitors which are equivalently connected in series to each other, comprising:
first and second resistors connected in series to each other, wherein the serial connection of the first and second resistors is connected in parallel to the smoothing unit;
a switching unit connected to a node (a reference point) between the first and second resistors and a node (a neutral point) between the first and second capacitors and configured to short and open between the reference point and the neutral point;
a control unit configured to control the switching unit to short between the reference point and the neutral point when a voltage of the reference point (a reference point voltage) and a voltage of the neutral point (a neutral point voltage) are different from each other; and
a voltage measuring element connected between the reference point and the neutral point.