US 11,863,062 B2
Capacitor discharge circuit
Benjamin J. Snyder, Boxborough, MA (US); Erin K. Nolan, Bolton, MA (US); Aline Elad, Ayer, MA (US); and John D. Walker, Bolton, MA (US)
Assigned to Raytheon Company, Waltham, MA (US)
Filed by Raytheon Company, Waltham, MA (US)
Filed on Apr. 27, 2018, as Appl. No. 15/965,070.
Prior Publication US 2019/0334363 A1, Oct. 31, 2019
Int. Cl. H02J 7/00 (2006.01); H02M 1/32 (2007.01); H02J 7/34 (2006.01)
CPC H02M 1/32 (2013.01) [H02J 7/345 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A capacitor discharge circuit, comprising:
a capacitor comprising a first plate and a second plate, and configured to store an electric charge, the capacitor having a capacitor voltage that is nonzero volts; and
discharge circuitry configured to discharge the electric charge so that the capacitor voltage becomes zero volts, the discharge circuitry being connected to the first plate, the discharge circuitry comprising:
a switch having a first terminal and a second terminal;
an inductor;
a discharge load having a resistor in series with the inductor, wherein one of the resistor or the inductor is connected to the first plate of the capacitor, wherein the other one of the resistor or the inductor is connected to the first terminal of the switch;
a controller configured to provide, in response to a control signal, a discharge signal to the switch to enable electrically coupling the discharge load to the second plate of the capacitor; and
current level sensing circuitry connected to the second terminal of the switch, wherein the current level sensing circuit is configured to provide the control signal to the controller in response to a current from the capacitor passing to the discharge load,
wherein the switch is electrically in series with both the current level sensing circuitry and the capacitor, and the switch is electrically connected between the current level sensing circuitry and the capacitor, and
wherein the discharge circuitry is configured, in response to the control signal, to modulate a level of the current passing from the capacitor to the discharge load over time between predetermined ranges of current levels by opening and closing of the switch.