US 11,984,725 B2
Flexible interconnection device and method for controlling a flexible interconnection device
He Liu, Shenzhen (CN); and ChunMing Yuan, Beijing (CN)
Assigned to Hitachi Energy Ltd, Zürich (CH)
Appl. No. 17/641,997
Filed by Hitachi Energy Ltd, Zürich (CH)
PCT Filed Sep. 11, 2019, PCT No. PCT/CN2019/105403
§ 371(c)(1), (2) Date Mar. 10, 2022,
PCT Pub. No. WO2021/046760, PCT Pub. Date Mar. 18, 2021.
Prior Publication US 2022/0385071 A1, Dec. 1, 2022
Int. Cl. H02J 3/18 (2006.01); H02J 3/16 (2006.01)
CPC H02J 3/18 (2013.01) [H02J 3/16 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A method for controlling a flexible interconnection device that includes a plurality of converters, the method comprising:
receiving a plurality of voltage signals indicating respective voltages of a plurality of load branches and a plurality of current signals indicating respective currents of the plurality of load branches;
determining reference active power values for each of the plurality of converters based on the plurality of voltage signals and a plurality of reference voltage signals;
determining reference reactive power values for each of the plurality of converters based on the plurality of voltage signals, the plurality of reference voltage signals and the plurality of current signals; and
controlling the plurality of converters based on the determined reference active power values and the determined reference reactive power values to distribute power between the plurality of load branches to achieve balanced load distribution;
wherein determining the reference active power values comprises:
computing a voltage difference between one of the plurality of voltage signals and a corresponding one of the plurality of reference voltage signals;
determining an absolute value of active power based on the voltage difference; and
computing an active power value by multiplying the absolute value with a sorting sign corresponding to the absolute value
wherein determining the absolute value of active power comprises:
integrating the voltage difference by a proportion integrator to generate an integral value; and
filtering the integrated value to generate the absolute value of active power.