US 11,942,896 B2
Protection device for a direct current electrical plant
Euro Marangoni, Lugo (IT); Armando Randi, Bagnacavallo (IT); and Carlo Bambi, Pieve di Cento (IT)
Assigned to SOCIETA' ELETTRICA S.R.L., Fusignano (IT)
Appl. No. 17/283,857
Filed by SOCIETA' ELETTRICA S.R.L., Fusignano (IT); and Euro Marangoni, Lugo (IT)
PCT Filed Oct. 10, 2019, PCT No. PCT/IB2019/058677
§ 371(c)(1), (2) Date Apr. 8, 2021,
PCT Pub. No. WO2020/075123, PCT Pub. Date Apr. 16, 2020.
Claims priority of application No. 102018000009387 (IT), filed on Oct. 11, 2018.
Prior Publication US 2021/0351744 A1, Nov. 11, 2021
Int. Cl. H02S 50/10 (2014.01); H02H 1/00 (2006.01); H02H 3/087 (2006.01); H02H 7/122 (2006.01)
CPC H02S 50/10 (2014.12) [H02H 1/0015 (2013.01); H02H 3/087 (2013.01); H02H 7/1222 (2013.01)] 17 Claims
OG exemplary drawing
 
1. A direct current electrical system, comprising:
one or more modules;
an inverter connected downstream of the one or more modules;
one or more protection switches inserted between the inverter and the modules;
at least one protection device, inserted in a branch which connects the one or more modules to the inverter, in order to detect the presence of an electric arc in the system and generate a fault signal and transmit it to the protection switch in order to open the switch,
wherein the at least one protection device comprises:
a first sensor provided with a first ring of ferromagnetic material configured to generate a first signal, representing a current flowing through a cable inserted in the ring;
a conditioning stage, having a bandpass filter, for conditioning the first signal generated by the first sensor;
a first threshold comparator, having a first, preset, adjustable voltage reference value, the first comparator being configured to receive as input the first signal conditioned by the conditioning stage;
a processor,
a second sensor, configured to generate a second signal representing a direct current component of the current flowing through the cable;
a second threshold comparator, having a second, preset, adjustable voltage reference value, the second comparator being configured to receive as input the second signal generated by the second sensor, wherein the processor is programmed to generate a fault signal in response to the occurrence of both of the following conditions:
the first signal exceeds the first reference value of the first comparator,
the second signal exceeds the second reference value of the second comparator.