US 12,463,441 B2
Charger
Leonard Mattheis, Waiblingen (DE); Christian Grobe, Itzehoe (DE); Tobias Frank Rastetter, Pinneberg (DE); and Nils Jakubietz, Burg (DE)
Assigned to Andreas Stihl AG & Co. KG, Waiblingen (DE)
Filed by Andreas Stihl AG & Co. KG, Waiblingen (DE)
Filed on Jan. 28, 2022, as Appl. No. 17/587,556.
Claims priority of application No. 21154433 (EP), filed on Jan. 29, 2021.
Prior Publication US 2022/0247194 A1, Aug. 4, 2022
Int. Cl. H02J 7/00 (2006.01); G01R 19/165 (2006.01)
CPC H02J 7/0045 (2013.01) [G01R 19/16533 (2013.01); H02J 7/0013 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A charger, comprising:
a plurality of electrical interfaces, wherein a respective electrical interface is able to be coupled to an electrical energy store to be charged, in order to charge the electrical energy store to be charged;
a common charge line which carries a charging potential during charging operation of the charger,
wherein a respective electrical interface comprises:
a first connection terminal which, when used as intended, is to be electrically connected to a corresponding connection terminal of the electrical energy store to be charged,
two field-effect transistors which are looped-in in anti-serial fashion between the first connection terminal and the common charge line,
at least one control unit which drives the two field-effect transistors of a respective electrical interface such that, at any one time, the first connection terminal of only a single electrical interface is electrically connected to the common charge line via the two field-effect transistors of the respective interface, and
a test device designed to check a correct switching function of both of the two field-effect transistors,
wherein the test device comprises a voltage measuring device designed to measure a voltage at a connection node of the two field-effect transistors, wherein the test device is designed to compare a measured voltage to an expected voltage which sets in at the connection node in the case of a correct switching function of the two field-effect transistors, a correct switching function of the two field-effect transistors being determined when the measured voltage corresponds to the expected voltage, and
wherein the test device comprises a first test voltage generation device configured to apply a first test potential to the first connection terminal, and/or a second test voltage generation device configured to apply a second test potential to the common charge line.