Patent ID: 11901750
Assignee: HAMILTON SUNDSTRAND CORPORATION
Field: Electrical machinery, apparatus, energy (Electrical engineering)
Classification: CPC H  B | IPC B  H

Claim 20:
21. A system comprising:
a first set of batteries coupled to a battery terminal;
a power converter coupled to a power converter terminal, wherein the battery terminal is coupled to the power converter terminal;
a first current limiting circuit in series with the first set of batteries, wherein the current limiting circuit comprises:
a first circuit comprising a first transistor in series with a first diode, wherein a first anode of the first diode is coupled to a first source of the first transistor, and wherein a first drain of the first transistor is coupled to a first node;
a second circuit comprising a second transistor in series with a second diode, wherein a first cathode of the second diode is coupled to a second drain of the second transistor, and wherein a second source of the second transistor is coupled to the first node;
a first resistor inductor (RL) circuit comprising a first resistor and a first inductor connected in series, wherein the first RL circuit, the first circuit, and the second circuit are arranged in parallel;

a first set of DC-link capacitors coupled between the power converter and the power converter terminal;
a second current limiting circuit in series with the first set of capacitors, wherein the second current limiting circuit comprises:
a third circuit comprising a third transistor in series with a third diode, wherein a second anode of the third diode is coupled to a third source of the third transistor, and wherein a third drain of the third transistor is coupled to a second node;
a fourth circuit comprising a fourth transistor in series with a fourth diode, wherein a second cathode of the fourth diode is coupled to a fourth drain of the fourth transistor, and wherein a fourth source of the fourth transistor is coupled to the second node; and
a second RL circuit, wherein the second RL circuit, the third circuit, and the fourth circuit are arranged in parallel; and

a controller configured to operate the first current limiting circuit in a plurality of modes comprising:
a battery discharge mode, wherein when in the battery discharge mode the controller causes the first transistor to not conduct current and the second transistor to conduct current; and
at least one of a first protection mode and a second protection mode, wherein:
the first protection mode comprises the controller detecting a short circuit associated with the power converter and causing the first, second, third, and fourth transistors to not conduct current; and
the second protection mode comprises the controller detecting a second short circuit associated with the first set of batteries and causing the first, second, third, and fourth transistors to not conduct current; and

a battery precharge mode, wherein when in the battery precharge mode the controller causes the third transistor and the fourth transistor to not conduct current, 10 and current flows through the second RL circuit;
a voltage imbalance mode, wherein when in the voltage imbalance mode the controller causes the first transistor and the second transistor to not conduct current, and current flows between at least a first battery and a second battery of the first set of batteries.